Feed intake, growth performance and carcass characteristics of Damara lambs fed bush-based rations from four encroacher bush species

Feed intake, growth performance and carcass characteristics of Damara lambs fed bush-based rations from four encroacher bush species | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Feed intake, growth performance and carcass characteristics of Damara lambs fed bush-based rations from four encroacher bush species Katrina Lugambo Shiningavamwe, Emmanuel Lutaaya, Johnfisher Mupangwa This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4241387/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 04 Jun, 2025 Read the published version in Tropical Animal Health and Production → Version 1 posted 5 You are reading this latest preprint version Abstract The effect of feeding bush-based finishing rations on the performance of Damara lambs was studied. Thirty weaned lambs weighing 16.7 ± 1.9 kg were allocated to five treatments in a completely randomized design over a 90-day feeding period. The control diet (T1), consisted of Lucerne (10%), grass hay (30%) and concentrate mix (60%). Treatments T2-T5 consisted of roughage (40%) from the milled bushes Senegalia mellifera, Dichrostachys cinerea, Terminalia sericea and Rhigozum trichotomum respectively, and concentrate mix (60%). At the end of the feeding trial, the lambs were slaughtered and carcass characteristics were evaluated. The average daily feed intake (ADFI) was affected (P < 0.05) by sex, treatment, week and treatment x week interactions. The ADFI for T1 exceeded (P 0.05) at weeks 6 to 10, but differed (P < 0.05) at other time points. The average daily gain (ADG) and feed conversion ratio (FCR) were affected (P < 0.05) by sex and treatment. The ADG (g/day) least squares means (± S.E) for T1 – T5 were 148.0 ± 6.9, 156.4 ± 6.9, 124.2 ± 6.9, 133.7 ± 6.9 and 133.7 ± 6.9, respectively. Treatment T2 had a better (P < 0.05) FCR compared to other bush-based treatments. Males had heavier (P < 0.05) final, hot and cold carcass weights than females. Lambs fed T4 had greater (P < 0.05) rib eye area than T1 (8.3 ± 0.5 vs. 5.9 ± 0.5 mm 2 ). Bush-based diets can serve as production diets for weaned sheep and result into acceptable weight gain and carcass quality. bush encroachment. average daily gain. finishing rations. feed resources. carcass characteristics Figures Figure 1 Figure 2 Introduction Sheep are predominantly raised on rangelands in the arid and semi-arid regions of the subtropics where they are able to utilize marginal pastures. A major constraint to such a sheep production system is the fluctuation in both quantity and quality of the feed supply on rangelands (Olafadehan and Adewumi, 2010 ). Consequently there is low animal productivity with animals taking longer to reach slaughter weights and often producing lower quality carcasses (Ben Salem et al., 2004 ). Global climate change is expected to increase the frequency of occurrence of extreme events like droughts further exacerbating the feed shortages in livestock production systems based on rangelands as the main feed resource. As an alternative, finishing sheep in the feedlot can play an essential role in preparing lambs for slaughter, as well as relieving the grazing pressure on pasture. Mutton and lamb producers in Namibia and South Africa use Lucerne and grass hay as roughage sources in feedlot diets (van der Merwe et al., 2020 ). However, the limited availability and high cost of these ingredients in the Namibian market often limit their use as roughage sources in feedlot diets. Hence, interventions to find affordable and sustainable alternative roughage sources are important for the sheep industry and the environment. In Namibia, there is an abundance of encroaching bushes that present an opportunity to be explored as a possible alternative roughage feed resource for livestock. Honsbein et al. ( 2018 ) evaluated the feeding value of Senegalia mellifera milled bush as a replacement for grass hay in total mixed feedlot diets of Sanga cattle, which obtained an average daily live weight gain of 880 g/day. To our knowledge, there is paucity of information on the feeding value of rangeland encroacher bush species, as alternative roughage fodders to the conventional feed like grass and Lucerne hay for ruminant livestock. In addition, it is also necessary to test performance of other ruminant species like sheep when finished on diets containing milled bush as a roughage source. Hafez ( 1987 ) for instance reported that sheep were more efficient in converting fibrous low-quality feedstuffs into meat and other livestock products than cattle. It was hypothesized that milled encroacher bushes of S . mellifera , Dichrostachys cinerea , Terminalia sericea and Rhigozum trichotomum could be used as suitable alternative roughage sources to grass hay, for feedlot animals and may improve the overall performance of sheep. Therefore, the objective of this study was to evaluate the effects of feeding the four encroacher bush species as alternative roughage to grass hay (conventional fodder) on the feed intake, growth performance and carcass characteristics of Damara lambs. Materials and Methods The feeding experiment was conducted at the Neudamm Campus of the University of Namibia, which is approximately 30 kilometres east of Windhoek in the Khomas region of Namibia. The campus is situated at 22°30'10.19" S latitude and 17°22'5.39" E longitude. All procedures conducted during this experiment were approved by the Animal Research Ethics Committee (ref: AREC/024/2020) of the University of Namibia. Feed ingredients and experimental diets The milled bush biomass of encroacher bush species used in this study was of the predominant encroacher species, namely Senegalia mellifera, Dichrostachys cinerea , T . sericea and R . trichotomum . Harvesting of the bushes was done between April and May 2019 and the harvested biomass was restricted to branches or twigs of ≤ 20 mm stem diameter. The fresh biomass was milled using a hammer mill to a particle size of 10 mm and air dried under shade until constant weight before being packed in bags and transported to Neudamm campus for storage until the feeding trial. Apart from bush biomass, other roughage sources used in the preparation of experimental diets were grass hay (mixed veld grass species) and Lucerne hay, which were also milled to particle sizes of 10 mm. The experimental diets were formulated to constitute 40% of different roughage sources and similar 60% concentrate made from a combination of different feed ingredients (Table 1 ). Except for bush biomass, all other ingredients were purchased from a commercial feed supplier. A conventional diet consisting of coarsely ground Lucerne (10%) and grass hay (30%) as roughage, was used as a control (T1), while each of the other four treatment diets (T2-T5) consisted of the selected bush species as roughage source at the same inclusion rate (40%) and the remaining portion (60%) consisted of the same combination of supplements. Batches of feed were mixed weekly and fed to the lambs. All treatment diets were formulated to meet nutrient requirements of growing sheep according to NRC (2007) recommendations. Table 1 Ingredients composition of the five treatment diets Treatment diets* Feed ingredient (kg “as is”) T1 T2 T3 T4 T5 Coarsely ground grass hay 30 0 0 0 0 Coarsely ground lucerne hay 10 0 0 0 0 Milled Bush 0 40 40 40 40 Yellow maize meal 22 20 20 19 20 Molasses syrup 5 5 5 5 5 HPC 30 30 32 32 33 32 Futterfos™ P14 1.5 1.5 1.5 1.5 1.5 Coarse salt 1.5 1.5 1.5 1.5 1.5 Total 100 100 100 100 100 * T1 control diet, T2 Senegalia mellifera- based diet, T3 Dichrostachys cinerea -based diet, T4 Terminalia sericea- based diet and T5 Rhigozum trichotomum -based diet; HPC 30 high protein concentrate with 30% crude protein; Futtterfos™ P14- Phosphate lick with 14% Phosphorus. Experimental animals and management Thirty (30) weaned 3-month old Damara lambs (15 males and 15 females) with a mean weaning weight of 16.7 ± 1.9 kg were used. The lambs were vaccinated with Multivax P™ (Intervet International B.V., The Netherlands) at the beginning of the trial to protect them against botulism, black quarter, pulpy kidney and clostridium. They were also treated with Dectomax™ (Pfizer Laboratories (Pty) Ltd, Sandton) against internal and external parasites. Experimental design and data collection The experiment was set up as a completely randomized design (CRD) with six (6) lambs per treatment (3 males and 3 females), to evaluate feed intake (FI) and the growth performance for 90 days, after an adaptation period of 14 days. The 30 lambs were randomly allocated to the 5 dietary treatments and housed individually in pens of 1 m 2 with concrete floors in an open-sided roofed shed, where they received treatment diets and water on an ad lib basis. After the adaptation period, the feed offered and feed refused daily were weighed and recorded to determine the feed intake. The daily feed was offered to each sheep in two portions, at 09h00 and 14h00. Initial body weights were obtained by weighing the lambs using an electronic scale (Micro T7E Scale; Premier Scale Services (Pty) Ltd) at the beginning of the adaptation period. Thereafter, the lambs were weighed weekly on the same day of the week in the morning before feeding, until the end of the experiment. Average daily gain (ADG) was calculated as difference between final and initial body weights divided by number of feeding days. Sampling and chemical composition analysis of experimental diets During the trial period, random samples of each treatment diet were taken once from a weekly batch, mixed and pooled separately in marked paper bags. At the end of the experiment period, all treatment diet samples were ground to pass through a 1 mm sieve (Retsch Mable mill; Retsch GmbH) and stored in plastic bottles for chemical analysis. The dry matter (DM) content of bush species samples was determined by drying the samples in a forced draught oven at 100°C for 24 h (AOAC, 2000). Ash was determined by incineration in a muffle furnace at 550°C for 6 h (AOAC, 2000). The crude protein (CP) method no. 978.04 (AOAC, 2005) was used to determine the total nitrogen content and CP was estimated by multiplying percentage of N content by a factor 6.25. Ether extract (EE) was determined using the AOAC method 920.39 (AOAC, 2000). Ash-free neutral detergent fibre (NDFom) and Ash-free acid detergent fibre (ADFom) were determined following the procedures of Mertens et al . (2002) with NDFom assayed without use of an alpha-amylase, but with sodium sulfite. Ash-free Acid detergent lignin (ADLom) was determined by placing dried ADF samples in 72% sulphuric acid (H 2 SO 4 ) (Mertens, 2015). Calcium and Phosphorus were determined using inductively coupled plasma atomic emission spectrometry (Sah and Miller, 1992 ). Slaughtering procedures At the end of the feeding experiment, all sheep were individually weighed to obtain the final weight (FW), after being fasted overnight, with only access to water, to avoid digesta contamination. They were then transported to the Neudamm abattoir for slaughter. Sheep were slaughtered in accordance with the prescribed animal ethics and welfare regulations, at the registered abattoir facilities of the Neudamm campus, under the required conditions for local abattoirs in Namibia. Animals were stunned to render them unconscious and to ensure that they did not suffer pain during slaughter. After stunning, sheep were slaughtered by cutting the carotids, jugular vein, oesophagus and trachea to allow blood to drain from the carcass. The carcasses were hanged on the bleeding rail and the dressing operation began after the bleeding process was completed. All slaughtering procedures were done under the supervision of a veterinarian, specialized in Veterinary Public Health. Carcass characteristics After dressing and evisceration procedures, carcasses grading was done visually according to the South African Meat Classification System for beef, lamb, mutton and chevon, according to the Government Notice No. R.863 of 1 September 2006 (Republic of South Africa, 2006 ), which is also adopted by the Meat Board of Namibia. The carcasses were weighed to obtain hot carcass weights (HCW). The pH of the carcasses was measured 1 hour (pH 1 ) after slaughter in the left Musculus longissimus dorsi at the area between 10th to 13th rib, using a portable digital pH meter with a penetration electrode and temperature probe. Subsequently, carcasses were chilled in a cooler under the temperature of 2–4°C for 24 hours to obtain the cold carcass weights (CCW). Cold carcass weight (CCW) was expressed as a proportion of the live weight at slaughter (SW) to determine the dressing percentage (Van der Merwe et al., 2020 ). The pH reading of the carcasses was taken again at 24 hours (pH 24 ) in the Musculus longissimus dorsi on the same spot where pH1 was taken. After 24 hours of chilling, the carcasses were then split into two halves down the spinal column by a longitudinal cut on the vertebral column using a meat band saw. The left side of the carcass was used for further measurements such as external length (CEL) of each carcass, shoulder and buttock circumferences (SC and BC, respectively), which were measured with a flexible tape measure following the procedure described by De Boer et al. ( 1974 ). The fat thickness was measured at ¼ (Fat Pos¼ ), ½ (Fat Pos½ ) and ¾ (Fat Pos¾) positions on the 12th rib from the chine bone end, with a vernier calliper and from these, average fat thickness was calculated (Lima et al. , 2015; Araújo et al., 2017). The eye-rib depth and the eye-rib width of the Musculus longissimus dorsi exposed by cutting the carcass between the 12th and 13th ribs were measured with a Vernier calliper (Ferreira et al ., 2012; Landim et al ., 2015). As per the method described by Ferreira et al . (2012), the area of Musculus longissimus dorsi was determined by measuring the maximal width of the muscle, denoted as “A” and its maximal depth “B” and then applying the values into the following equation: (A/2 × B/2) × \(\pi\) , where \(\pi\) equals to 3.1416. The three-rib cut was weighed and physically separated by blunt dissection into bone, lean and fat tissue which were weighed individually and expressed as a proportion of the cut as described by Van der Merwe et al. ( 2020 ). Statistical Analysis The chemical composition of the diets was subjected to analysis of variance (ANOVA) using Proc GLM (SAS, 2009). Similarly, FCR and ADG were subjected to analysis of variance (ANOVA) using Proc GLM (SAS, 2009) with the effects in the model being sex and treatment. Intake is a function of the body weight (W) of the animal, hence analyses were based on metabolic body weight (W 0.75 ). The model (1) included the effects: sex, treatment, week and treatment x week interactions. Data was analysed using Proc Mixed (SAS, 2009) which takes into account correlation between repeated measures on an individual and the Bayesian Information Criterion (BIC) which compares covariance structures based on goodness of fitness criteria, was used to select the appropriate covariance structure (Littell et al., 1998 ), which was simple. Estimate statements were used in Proc Mixed (SAS, 2009) to compare means and obtain standard errors. Effects were considered significant at P < 0.05. Y ijkl = µ + F i + S j + W k + FW ik + e ijkl (1) Where: Y ijkl = feed intake; µ = overall mean; F i = effect of treatment (i = T1, T2… T5); S j = effect of sex (j = male, female); W k = effect of week (k = 1,2,3…13); FW ik = interaction effect between treatment and week; e ijkl = random error term explaining variation among experimental units (EU) on the same treatment. A similar model to (1) was used to fit body weights, but with the additional interaction effect of treatment by sex. The best covariance structure for body weights was ante-dependence [ANTE(1)]. The data on carcass characteristics were subjected to analysis of variance (ANOVA) using the General Linear Model (GLM) procedure (SAS, 2009). The effects in the model were treatment (T1-T5), sex and their interactions. Data were checked for normality and transformation was carried out where necessary, before statistical analysis. Means were separated using the Turkeys’ Studentised range test. Results Chemical composition of treatment diets The chemical composition of the treatment diets used in this study is shown in Table 2 . The crude protein (CP) for T1 was similar to T2 but higher (P = 0.03) than T3, T4 and T5, which did not differ (P > 0.05). The neutral detergent fibre (NDFom) and acid detergent fibre (ADFom) contents for T3 were higher (P < 0.01) than those of the other four treatment diets. Diet T1, however, had the lowest ADFom, while T4 and T5 had the lowest NDFom content. Diet T1 also had lower (P < 0.01) acid detergent lignin (ADLom) content compared to the bush-based diets. The ether extract (EE) content was higher (P 0.05). Table 2 Chemical composition (g/kg DM) of the five treatment diets Treatment diets* Variables T1 T2 T3 T4 T5 SEM P-value Dry matter (DM) 910 b 903 c 918 a 890 d 904 c 1.04 < 0.01 Organic matter (OM) 869 c 890 b 904 a 869 d 885 b 1.07 < 0.01 Crude protein (CP) 146 a 143 ab 135 c 140 bc 139 bc 1.53 0.03 Neutral detergent fibre (NDFom) 415 b 422 b 506 a 386 c 386 c 5.12 < 0.01 Acid detergent fibre (ADFom) 221 d 226 b 365 a 245 c 240 c 3.37 < 0.01 Acid detergent lignin (ADLom) 44.3 c 73.3 b 93.3 a 93.3 a 84.1 ab 3.55 < 0.01 Ether extract (EE) 16.0 d 16.8 c 19.3 a 20.0 a 17.5 b 0.16 < 0.01 Ash 131 a 110 c 96 d 131 a 115 b 1.07 < 0.01 Calcium (Ca) 9.3 c 11.5 b 9.6 c 13.2 a 9.7 c 0.27 < 0.01 Phosphorus (P) 0.507 c 0.475 d 0.410 e 0.570 a 0.530 b 0.002 < 0.01 Metabolizable energy (MJ/kg) 1 9.3 10.0 9.6 8.9 9.8 N/A N/A * T1 control diet, T2 = Senegalia mellifera- based diet, T3 Dichrostachys cinerea -based diet, T4 Terminalia sericea- based diet and T5 Rhigozum trichotomum -based diet 1 Estimated metabolizable energy (ME) values; SEM Standard error of means; N/A = not applicable; a − d Means with different superscripts within a row differ ( P < 0.05 ). Feed intake The average daily feed intake (ADFI) of the lambs (kg DM/kg W 0.75 per day) during the ninety (90) days feeding period was affected (P < .05) by sex, treatment, week and treatment * week interaction (Fig. 1 ). Averaged over the trial period, the ADFI of T1 exceeded (P < 0.05) that of other treatments. * T1 control diet; T2 Senegalia mellifera- based diet; T3 Dichrostachys cinerea -based diet; T4 Terminalia sericea- based diet and T5 Rhigozum trichotomum -based diet The ADFI generally increased from week 1 to week 6–7 and then stabilized, although lowest intake was for T2 and T3, which also showed the greatest lag. The ADFI for T1 exceeded (P 0.05). The ADFI of diets T2 and T3 were similar (P > 0.05) except at week 8. The ADFI of T4 exceeded (P < 0.05) that of T2 and T3 at most time points. ADFI of T5 exceeded (P < 0.05) that of T3 from weeks 4 to 10. From estimated contrasts, the ADFI of the control diet appears to have peaked at week 6 where it plateaued. The ADFI for diets T2, T3, T4 and T5 reached their maximum at week 7 where they remained stable. The least squares mean (± S.E) (kg) for ADFI of females exceeded (P < 0.05) that for males (0.121 ± 0.001 vs. 0.118 ± 0.001) Growth performance The live weights were influenced (P < 0.05) by week, treatment * week and treatment * sex interactions. Figure 2 shows the least squares means of body weights for lambs on the different diets. The body weights increased linearly, but with fluctuations by diet. Only T2 body weights exceeded (P = 0.04) those of T4 at week 13. The control diet (T1) did not differ (P > 0.05) from other treatments. * T1 conventional feedlot diet, T2 Senegalia mellifera- based diet, T3 Dichrostachys cinerea -based diet, T4 Terminalia sericea- based diet and T5 Rhigozum trichotomum -based diet The least squares means for growth performance are shown in Table 3 . With the exception of diet T4, there were no differences (P > 0.05) in live weights between males and females within in each treatment diet; females on T4 were heavier (P = 0.0001) than males. The ADG and FCR were affected (P < 0.05) by sex and treatment. Treatment T2 gave higher (P < 0.05) ADG than other treatments. The least squares means for ADG (g/day) were 124.9 ± 4.3 for females and 153.5 ± 4.3 for males. Treatment T2 had a better (P 0.05) to the control (T1). The FCR for females was 9.8 ± 0.3 and for males was 8.1 ± 0.3. Table 3 Least squares means (± SEM) of growth variables for Damara lambs fed five diets from different roughage sources Treatment diets* Variable T1 T2 T3 T4 T5 SEM P-value Initial weight (kg) 16.2 16.3 17.7 16.2 17.3 0.77 0.56 Final weight (kg) 29.7 30.6 28.7 28.4 29.4 0.87 0.43 Total gain (kg) 13.5 14.2 11.8 12.2 12.2 0.83 0.24 #Average daily gain (g/day) 148.0 b 156.4 a 124.2 b 133.7 b 133.7 b 6.9 < 0.05 #Feed conversion ratio 8.8 ab 7.6 b 9.5 ab 9.6 a 9.4 a 0.5 < 0.05 #Body weights (kg) for males 23.4 a 22.9 a 23.5 a 19.8 b 23.3 a 1.0 0.01 #Body weights (kg) for females 22.7 b 22.8 b 22.7 b 25.0 a 23.8 b 1.0 0.01 * T1 control diet, T2 Senegalia mellifera- based diet, T3 Dichrostachys cinerea -based diet, T4 Terminalia sericea- based diet and T5 Rhigozum trichotomum -based diet; a − d Means with different superscripts within a row differ ( P < 0.05 ). # Least squares means; SEM Standard error of means Carcass characteristics The final weight (FW) and carcass characteristics results are presented in Table 4 . The lambs from all five treatment groups visually scored similarly (score 1) in terms of subcutaneous fat cover, and they all fell under the same carcass grade A1. Treatment did not influence (P = 0.09) hot carcass weight (HCW). The FW, HCW and cold carcass weight (CCW) were influenced (P < 0.05) by sex. Irrespective of the treatment diet, the FW, HCW and CCW were lighter (P 0.05) for: carcass yield; average subcutaneous fat thickness and fat thickness taken at three different positions over the Musculus longissimus dorsi (the rib-eye muscle); pH 24 ; carcass lean; carcass external length (CEL); buttock circumference (BC); and rib-eye width. Treatment diets affected (P < 0.05) rib-eye area (REA). Lambs on treatments T1 and T5 had lower (P < 0.05) rib eye area (REA) than those on T4. The pH 1 values were influenced (P < 0.05) by treatment. Lambs on treatment T5 had higher (P < 0.05) pH 1 values than those on other treatments. Table 4 Slaughter weight and carcass characteristics least squares means (± SEM) of the Damara lambs fed different diets Variables Treatment Sex P values T 1 T 2 T 3 T4 T5 F M Treatment Sex Carcass grade A1 A1 A1 A1 A1 FW (kg) 29.7 ± 0.9 30.6 ± 0.7 28.7 ± 0.7 28.4 ± 0.7 29.4 ± 0.7 28.0 ± 0.4 b 30.7 ± 0.4 a 0.17 < 0.05 HCW (kg) 12.3 ± 0.3 12.3 ± 0.3 11.3 ± 0.3 11.3 ± 0.3 11.5 ± 0.3 11.4 ± 0.2 b 12.1 ± 0.2 a 0.09 0.03 CCW (kg) 11.9 ± 0.3 11.8 ± 0.3 10.9 ± 0.3 10.9 ± 0.3 11.0 ± 0.3 11.0 ± 0.2 b 11.6 ± 0.2 a 0.11 0.05 CCD (%) 40.0 ± 0.8 38.4 ± 0.8 37.7 ± 0.8 38.4 ± 0.8 37.4 ± 0.8 39.0 ± 0.5 37.8 ± 0.5 0.18 0.09 CEL (cm) 56.7 ± 0.8 54.8 ± 0.8 54.8 ± 0.8 54.0 ± 0.8 54.2 ± 0.8 54.7 ± 0.5 55.1 ± 0.5 0.18 0.65 SC (cm) 21.8 ± 0.4 22.0 ± 0.4 21.2 ± 0.4 20.3 ± 0.4 21.0 ± 0.4 21.1 ± 0.3 21.4 ± 0.3 0.05 0.48 BC (cm) 34.8 ± 0.6 35.2 ± 0.6 35.0 ± 0.6 34.0 ± 0.6 35.2 ± 0.6 34.8 ± 0.4 34.9 ± 0.4 0.67 0.91 pH 1 5.6 ± 0.1 b 5.9 ± 0.1 b 5.8 ± 0.1 b 5.8 ± 0.1 b 6.2 ± 0.1 a 5.8 ± 0.1 5.9 ± 0.1 0.01 0.74 pH 24 5.3 ± 0.04 5.3 ± 0.04 5.3 ± 0.04 5.3 ± 0.04 5.3 ± 0.04 5.3 ± 0.03 5.3 ± 0.03 0.86 0.28 Fat_1(mm) 3.3 ± 0.5 4.1 ± 0.5 2.6 ± 0.5 2.7 ± 0.5 2.9 ± 0.5 3.5 ± 0.3 2.7 ± 0.3 0.31 0.12 Fat_2 (mm) 2.7 ± 0.4 2.5 ± 0.4 2.0 ± 0.4 2.4 ± 0.4 1.8 ± 0.4 2.3 ± 0.3 2.2 ± 0.3 0.30 0.59 Fat_3 (mm) 2.8 ± 0.4 2.0 ± 0.4 2.2 ± 0.4 3.1 ± 0.4 2.4 ± 0.4 2.7 ± 0.3 2.3 ± 0.3 0.28 0.30 Avg fat (mm) 3.0 ± 0.3 2.8 ± 0.3 2.3 ± 0.3 2.8 ± 0.3 2.4 ± 03 2.9 ± 0.2 2.4 ± 0.2 0.43 0.13 Rib eye-width (cm) 4.4 ± 0.1 4.5 ± 0.1 4.7 ± 0.1 4.7 ± 0.1 4.5 ± 0.1 4.5 ± 0.1 4.6 ± 0.1 0.29 0.51 Rib eye-depth (cm) 1.7 ± 0.1 b 2.0 ± 0.1 ab 2.0 ± 0.1 ab 2.2 ± 0.1 a 1.9 ± 0.1 b - - 0.05 - Rib eye area (cm 2 ) 5.9 ± 0.5 b 7.1 ± 0.5 ab 7.2 ± 0.5 ab 8.3 ± 0.5 a 6.8 ± 0.5 b - - 0.038 - * T1 control diet, T2 Senegalia mellifera- based diet, T3 Dichrostachys cinerea -based diet, T4 Terminalia sericea- based diet and T5 Rhigozum trichotomum -based diet. FW Final weight; HCW hot carcass weight; CCW cold carcass weight; CCD cold carcass dressing; CEL carcass external length; SC shoulder circumference; BC buttock circumference; SEM standard error of the mean; F Female; M Male. ab Means with different superscripts within a row differ ( P < 0.05 ). Discussion Chemical composition of treatment diets It is a general practice to include a minimum amount of roughage in high-concentrate feedlot diets to maintain rumen health and reduce digestive disorders (Mertens, 2002 ). According to Jolly and Wallace ( 2007 ), ruminants appear to differ in their minimum fibre requirements; sheep in particular require a minimum of 10% roughage in the diet. However, in this study, all diets contained 40% roughage from different sources. Mertens ( 2002 ) cautioned against feeding an excessive amount of fibre because it can increase rumen fill and reduce the dry matter intake (DMI), which subsequently also reduces animal growth. In this study, the NDF contents of the diets were 50% or below and was lower than the concentration suggested (60–65%) to limit intake and digestibility of nutrients in ruminants (Van Soest et al., 1991 b). Similarly, Van de Vyver et al. ( 2014 ) also used feedlot diets for lambs with the NDF contents ranging from 24.3–42.1%, where Lucerne hay was replaced with different inclusion levels of maize silage as a roughage source. The NDF contents of the five treatment diets used in this study (Table 1 ) were, however, higher than the recommended range of 15 to 20% NDF by Smith ( 2008 ). Feed intake Feed intake is a major factor that influences the amount of nutrients available to the lamb in order to realise its growth potential (van der Merwe et al., 2020 ). A key concern of high proportions of roughage in feedlot rations is the high NDF content, which may physically restrict the dry matter intake through rumen fill (Jolly and Wallace, 2007 ; Oba and Allen, 1999 ). Intake is a function not only of the NDF concentration, but also of the source of fibre (Ruiz et al., 1995 ), which partly explains the variability in intake of diets formulated from different roughage sources. Notwithstanding the 2-week adjustment period, the feed intake increased from week 1 to 6 for all treatments, which may indicate a gradual adjustment of the rumen microbes to the diets. Hence animals may require a longer adjustment period (6–8 weeks) in feeding trials involving highly fibrous diets (40%) as implemented in this study. Mapiye et al. ( 2009 ) also suggested a longer adjustment period for cattle supplementation diets formulated using Acacia karroo leaf-meal due to the low diet palatability. Peak ADFI was attained earlier at 6 weeks for T1 compared to 7 weeks for T2 – T5, which may be explained by the higher ADFom and ADLom in bush-based diets requiring a longer adaptation period for the rumen microbes. The ADFI was affected by treatment * week interactions, which may be partly due to the inevitable variation in the supplied feed caused by natural variability by batch in the ingredients particularly for the bush material, which was harvested from different farms and over varying terrain and soils that ultimately may affect the physical and chemical characteristics of the diets. Flores-mar et al. ( 2018 ) replaced alfalfa hay with sorghum straws as roughage source and obtained similar dry matter intake when diets were formulated to contain the same percentage of forage NDF. This was not the case in the current study, as the diets were only formulated to contain similar inclusion levels of roughage sources but not the NDF content. The digestibility coefficients for DM, OM, CP, NDFom and ADFom for T1 generally exceeded those for other treatments (Shiningavamwe, 2022 ), which may have contributed to higher ADFI for T1 compared to the bush-based diets. Treatments T4 and T5 had lower NDFom compared to T2 and T3, which possibly contributed to a faster rate of digestion, hence reducing rumen fill. Other factors including high palatability and high passage rate (Jolly and Wallace, 2017) may have contributed to the greater intake of T4 and T5 than T2 and T3. Worthy noting is the considerable feed wastage due to the sorting behaviour when feeding lambs observed during the trial, which was solved earlier in the trial by addition of water (200 ml) to the feed, which helped in binding the feed ingredients, hence reducing the sorting and selection of feed components. Growth performance The non-significant contrasts of body weights for sheep on the control diet versus the rest of the diets across the 13 weeks, is surprising given that bush-based diets on account of their higher ADFom and ADLom (Table 2 ), should have restricted intake and hence body weight gains. This result, however, implies the equivalence of bush-based diets to grass hay in conventional diets in serving as a roughage source for moderate live weight gains. Superior performance on T2 compared to other diets may be attributed to the higher metabolizable energy content, high nutrients digestibility and a better amino acid profile (Shiningavamwe, 2022 ). Unlike the body weights which were affected by treatment x week and treatment x sex interactions, ADG and FCR are summary measures that provide aggregate performance and may mask the inherent fluctuations and subtle differences among animals under different treatments. The differences in growth rates of males and females lambs observed in this study among the different treatment diets were similar to the observations by Rodríguez et al. ( 2008 ) in a fattening study on Assaf lambs, which was partly associated with dietary selection by animals of different sex. These authors found that the growth rates were lower in females than in males which were linked to similar trends in their dry matter and crude protein intake. According to van der Merwe et al. ( 2020 ), for profitable production, producers often aim for an ADG of 300 g/day and FCR of 5.0 kg feed/kg weight gain, depending on the breed and type of feed used in the finishing system. In this study, the best ADG (156.4 ± 6.9 g/day) and FCR (7.9 ± 0.5) were obtained with T2, which were far more inefficient than the proposed figures above. The poorer performance for ADG and FCR in the present study could be related to the high inclusion rate of low-quality roughage sources than most conventional feedlot diets, which usually contain 20% or less roughage. Ismail and Obeidat ( 2023 ) who used Awassi lambs with a 25% roughage diet of wheat straw and olive leaves obtained ADG in the range of 218 to 235 g/day and FCR in the range 4.19 to 4.52. Van de Vyver et al. ( 2014 ) who replaced lucerne hay with maize silage as roughage source, reported similar FCR to T1 and T2 in this study. As indicated above, however, this level of FCR is not optimal for the production of sheep in a feedlot. Therefore, future research is warranted to optimize these diets to specification levels for growing lambs in the feedlot, with special focus on inclusion levels of each encroacher species depending on their physical and chemical fibre characteristics. There may also be a need to chemically or enzymatically treat bush-based feeding material so as to improve nutrient utilization (Adesogan et al., 2019 ). Carcass characteristics Carcass classification Carcass classification systems were developed to inform processors and consumers about the quality of the carcass and thus to distinguish its market value (Brand et al., 2018 ). In the present study, all carcasses of the Damara lambs in the five treatment diets fell in the same age category (A: with no permanent incisors) and fatness score 1, which gave an overall A1 grade. The age category was expected to be similar since they were all born within the same lambing season. The A1 grading could be explained by the fact that Damara sheep are fat-tailed and much of the body fat is accumulated around the tail with minor fat deposits in the rest of the body (Kleemann et al., 2000 ; Tshabalala et al., 2003 ; Almeida, 2011 ; Wilkes et al., 2012 ; Almeida et al., 2014 ). Therefore, this implies that the milled bush diets are good enough to produce lean meat. Carcass measurements Final, hot carcass and cold carcass weights were heavier in males than females which is consistent with findings by Simela et al . (2011) in goats and Van der Merwe et al. ( 2020 ) in lambs. Dressing percentage was in the range 37.4 to 40%, which is similar to what was reported in Menz sheep (Assefa et al., 2008 ), but this falls far short of dressing percentage reported in other studies for example: 46.1–48.3% (Cardoso et al., 2021 ); 49.4–50.2% (Rezaei et al., 2013 ); 59.9% (Simela et al., 2004 ). Dressing percentage is affected by live weight, fatness, time off water and feed, sex and breed (Warmington and Kirton, 1990 ). Higher growth rates have been typically associated with higher dressing percentages (Seoni et al., 2018 ) and given that ADG in this study was in the range 124 to 156 g/day, the slower growth could have contributed to the lower dressing percentage. Wilkes et al. ( 2012 ) reported dressing percentage in Damara sheep of 53.2 ± 1.9%, which reflected greater fatness compared to Merino (dressing percentage = 41.5 ± 1.8%). Results of this study suggest that while bush-based diets may be able to meet maintenance requirements, the inclusion rate used in this study might be high for supporting optimal growth in feedlots. Further studies are needed to determine optimal inclusion levels of browse material in feed rations and to determine whether chemical or biological treatment may improve their utilization. The pH 1 for T5 was slightly higher compared to other treatments which may be attributed to low muscle glycogen reserve possibly due to low energy supply (Vestergaard et al., 2000 ). Although the diets were formulated to be iso-energetic, diet T5 had the lowest DM and OM digestibility (Shiningavamwe, 2022 ) which could have contributed to low energy reserves. It was, however, observed that the ultimate pH 24 was similar for the different diets. Dietary energy intake impacts muscle glycogen reserves (Daly et al., 2006 ; De Brito et al., 2016 ) and these in turn affect muscle pH values. This implies that the observed similar ultimate pH could be attributable to a different factor not muscle glycogen reserves as influenced by dietary energy levels. Muscle pH values affect colour, water-holding capacity and sensory attributes of lamb meat (Ferguson and Gerrard, 2014 ). In this study muscle glycogen reserves were not determined and neither was the eating quality assessed but these would be useful in future studies to determine effects of different bush-based diets on meat sensory attributes. Rib eye area (REA) is associated with the amount of muscle in a carcass and is indicative of muscle development and yield of high value cuts (Williams, 2002 ). The results indicate greater muscle development for animals on diets T2, T3 and T4 compared to T1 and T5; similarly rib eye depth was greater in T4 than T1. Even after adjusting for differences in CCW, the advantage of T4 over T1 and T5 were still evident for both rib eye depth and REA. It is not clear why the T4 diet could have positively influenced muscling without impacting ADG. Conclusions The milled bush of the four-encroacher species can be used to partially replace grass and Lucerne hay in diets for weaned lambs. Lambs fed T2 had higher ADG and better FCR than other treatment groups, but still fell short of targets for commercial sheep feedlots, probably due to low nutrient digestibility of the bush roughage sources. The lambs fed the bush-based diets had carcass characteristics that were comporable to those on the control diet. Cold carcass weights, grading, ultimate pH and fat thickness were similar among treatments. Although encroacher bush could be used to partially substitute grass hay, the low dressing percentage possibly related to slow growth rates is of particular concern because it impacts profitability. Therefore, more research is needed to develop efficient feeding strategies or processing such as pelletizing, that encourage inclusion of milled bush as roughage source for ruminants. Declarations Acknowledgements. The first author is grateful for financial support to her studies by the Finnish Embassy in Namibia through the Bush–to-Feed Project implemented by the University of Namibia. We would also like to thank the Ministry of Agriculture, Water and Land Reform (MAWLR) for granting a full-time study leave and research support to SKL. The University of Namibia is also thanked for the additional support in carrying out the research. Authors’ contribution : Shiningavamwe Katrina Lugambo conceptualized the study, carried out the trials and wrote the initial draft of the manuscript. Lutaaya Emmanuel co-supervised the first author, advised on the experimental design, carried out statistical analysis, revised the draft manuscript. Mupangwa Johnfisher was the main supervisor to the first author; gave general oversight for the study; review and editing. Data availability. The datasets generated for the current study are available from the corresponding author on reasonable request. Ethics approval . This research was approved by the University of Namibia Research Ethics Committee (UREC) (AREC/024/2020). Funding . The Finnish Embassy in Namibia through the Bush–to-Feed Project implemented by the University of Namibia provided funding support to SKL. Conflict of interest. The authors declare no competing interests. References Adesogan A., Arriola, K., Jiang Y., Oyebade A., Paula, E., Pech-Cervantes, A., Romero, J., Ferraretto, L. and Vyas, D., 2019. Symposium review: Technologies for improving fiber utilization . https://doi.org/10.3168/jds.2018-15334 Almeida, A. M, Kilminster, T., Scanlon, T., Araujo, S. S., Milton, J., Oldham, C. and Greef, J. C., 2014. 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Journal of Animal Science, 80 (E-Suppl_2), E 183 – E188. https://doi.org/10.2527/animalsci2002.80e-suppl_2e183x Cite Share Download PDF Status: Published Journal Publication published 04 Jun, 2025 Read the published version in Tropical Animal Health and Production → Version 1 posted Editorial decision: Accept with minor revision 17 Jul, 2024 Reviewers agreed at journal 14 Jun, 2024 Reviewers invited by journal 07 May, 2024 Editor assigned by journal 19 Apr, 2024 First submitted to journal 18 Apr, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4241387","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":299667604,"identity":"fbc3e556-eb1b-403c-b25e-25d31fcc22da","order_by":0,"name":"Katrina Lugambo Shiningavamwe","email":"","orcid":"","institution":"Ministry of Agriculture, Water \u0026 Land Reform","correspondingAuthor":false,"prefix":"","firstName":"Katrina","middleName":"Lugambo","lastName":"Shiningavamwe","suffix":""},{"id":299667606,"identity":"1682d96f-b607-4413-8da1-63bbb35cc48c","order_by":1,"name":"Emmanuel Lutaaya","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAxUlEQVRIiWNgGAWjYDACdijNT7wWZgbGBhAt2UCyFoMDxOrgZ+Yxf/Cj5rC88Y3cg59uMNyRJ6hFspnHsLHn2GHDbTfykqVzGJ4ZEnSgwWEewwYetsOM227kGAC1HGYkqMUeqKXxz7/D9ptn5Bj/BmqxJ2wLM49hM2/b4cQNEjlmIFsSCWqROMxWOFu2Lz15xpk3ZtY5BoeTCWrhb2/e8PHNN2vb/vYc49s5FYdtCWqBgmaYO4lUDwR1xCsdBaNgFIyCkQcAyYo9NZNX3O4AAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0002-6006-8483","institution":"University of Namibia","correspondingAuthor":true,"prefix":"","firstName":"Emmanuel","middleName":"","lastName":"Lutaaya","suffix":""},{"id":299667607,"identity":"53cbaa2e-cd01-48fb-b521-c7d96568515d","order_by":2,"name":"Johnfisher Mupangwa","email":"","orcid":"","institution":"University of Namibia","correspondingAuthor":false,"prefix":"","firstName":"Johnfisher","middleName":"","lastName":"Mupangwa","suffix":""}],"badges":[],"createdAt":"2024-04-09 11:04:58","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4241387/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4241387/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s11250-025-04473-w","type":"published","date":"2025-06-04T15:57:30+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":56483314,"identity":"3da1e506-91a7-4250-b9ca-2d7e9c596436","added_by":"auto","created_at":"2024-05-14 19:16:57","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":210494,"visible":true,"origin":"","legend":"\u003cp\u003eThe average daily feed intake (kg DM/kg W\u003csup\u003e.75\u003c/sup\u003e per day) of weaned Damara sheep\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;* \u003cem\u003eT1\u003c/em\u003e control diet; \u003cem\u003eT2\u003c/em\u003e \u003cem\u003eSenegalia mellifera-\u003c/em\u003ebased diet;\u003cem\u003e T3\u003c/em\u003e \u003cem\u003eDichrostachys cinerea\u003c/em\u003e-based diet;\u003c/p\u003e","description":"","filename":"Picture1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4241387/v1/7ca4255be00b42c85d07c2b0.jpg"},{"id":56483315,"identity":"32253d46-bed6-4fca-af8d-d354c0eaf204","added_by":"auto","created_at":"2024-05-14 19:16:57","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":221502,"visible":true,"origin":"","legend":"\u003cp\u003eLeast squares means of body weight (kg) of Damara lambs during the feeding period\u003c/p\u003e\n\u003cp\u003e*\u003cem\u003eT1 \u003c/em\u003econventional feedlot diet, \u003cem\u003eT2 Senegalia mellifera-\u003c/em\u003ebased diet,\u003cem\u003e T3\u003c/em\u003e \u003cem\u003eDichrostachys cinerea\u003c/em\u003e-based diet, \u003cem\u003eT4\u003c/em\u003e \u003cem\u003eTerminalia sericea-\u003c/em\u003ebased diet and \u003cem\u003eT5\u003c/em\u003e \u003cem\u003eRhigozum trichotomum\u003c/em\u003e-based diet\u003c/p\u003e","description":"","filename":"Picture2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4241387/v1/41833d4f02b048f605ae1cf1.jpg"},{"id":84242578,"identity":"ada4142c-4a8c-4a87-b017-d4117fdca9cc","added_by":"auto","created_at":"2025-06-09 16:09:47","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1509659,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4241387/v1/9aa64624-ead6-4542-9a24-7586ae07890d.pdf"}],"financialInterests":"","formattedTitle":"Feed intake, growth performance and carcass characteristics of Damara lambs fed bush-based rations from four encroacher bush species","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSheep are predominantly raised on rangelands in the arid and semi-arid regions of the subtropics where they are able to utilize marginal pastures. A major constraint to such a sheep production system is the fluctuation in both quantity and quality of the feed supply on rangelands (Olafadehan and Adewumi, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). Consequently there is low animal productivity with animals taking longer to reach slaughter weights and often producing lower quality carcasses (Ben Salem et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2004\u003c/span\u003e). Global climate change is expected to increase the frequency of occurrence of extreme events like droughts further exacerbating the feed shortages in livestock production systems based on rangelands as the main feed resource.\u003c/p\u003e \u003cp\u003eAs an alternative, finishing sheep in the feedlot can play an essential role in preparing lambs for slaughter, as well as relieving the grazing pressure on pasture. Mutton and lamb producers in Namibia and South Africa use Lucerne and grass hay as roughage sources in feedlot diets (van der Merwe et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). However, the limited availability and high cost of these ingredients in the Namibian market often limit their use as roughage sources in feedlot diets. Hence, interventions to find affordable and sustainable alternative roughage sources are important for the sheep industry and the environment.\u003c/p\u003e \u003cp\u003eIn Namibia, there is an abundance of encroaching bushes that present an opportunity to be explored as a possible alternative roughage feed resource for livestock. Honsbein et al. (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) evaluated the feeding value of \u003cem\u003eSenegalia mellifera\u003c/em\u003e milled bush as a replacement for grass hay in total mixed feedlot diets of Sanga cattle, which obtained an average daily live weight gain of 880 g/day. To our knowledge, there is paucity of information on the feeding value of rangeland encroacher bush species, as alternative roughage fodders to the conventional feed like grass and Lucerne hay for ruminant livestock. In addition, it is also necessary to test performance of other ruminant species like sheep when finished on diets containing milled bush as a roughage source. Hafez (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e1987\u003c/span\u003e) for instance reported that sheep were more efficient in converting fibrous low-quality feedstuffs into meat and other livestock products than cattle. It was hypothesized that milled encroacher bushes of \u003cem\u003eS\u003c/em\u003e. \u003cem\u003emellifera\u003c/em\u003e, \u003cem\u003eDichrostachys cinerea\u003c/em\u003e, \u003cem\u003eTerminalia sericea\u003c/em\u003e and \u003cem\u003eRhigozum trichotomum\u003c/em\u003e could be used as suitable alternative roughage sources to grass hay, for feedlot animals and may improve the overall performance of sheep. Therefore, the objective of this study was to evaluate the effects of feeding the four encroacher bush species as alternative roughage to grass hay (conventional fodder) on the feed intake, growth performance and carcass characteristics of Damara lambs.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003eThe feeding experiment was conducted at the Neudamm Campus of the University of Namibia, which is approximately 30 kilometres east of Windhoek in the Khomas region of Namibia. The campus is situated at 22\u0026deg;30'10.19\" S latitude and 17\u0026deg;22'5.39\" E longitude. All procedures conducted during this experiment were approved by the Animal Research Ethics Committee (ref: AREC/024/2020) of the University of Namibia.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eFeed ingredients and experimental diets\u003c/h2\u003e \u003cp\u003eThe milled bush biomass of encroacher bush species used in this study was of the predominant encroacher species, namely \u003cem\u003eSenegalia mellifera, Dichrostachys cinerea\u003c/em\u003e, \u003cem\u003eT\u003c/em\u003e. \u003cem\u003esericea\u003c/em\u003e and \u003cem\u003eR\u003c/em\u003e. \u003cem\u003etrichotomum\u003c/em\u003e. Harvesting of the bushes was done between April and May 2019 and the harvested biomass was restricted to branches or twigs of \u0026le;\u0026thinsp;20 mm stem diameter. The fresh biomass was milled using a hammer mill to a particle size of 10 mm and air dried under shade until constant weight before being packed in bags and transported to Neudamm campus for storage until the feeding trial.\u003c/p\u003e \u003cp\u003eApart from bush biomass, other roughage sources used in the preparation of experimental diets were grass hay (mixed veld grass species) and Lucerne hay, which were also milled to particle sizes of 10 mm. The experimental diets were formulated to constitute 40% of different roughage sources and similar 60% concentrate made from a combination of different feed ingredients (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Except for bush biomass, all other ingredients were purchased from a commercial feed supplier.\u003c/p\u003e \u003cp\u003eA conventional diet consisting of coarsely ground Lucerne (10%) and grass hay (30%) as roughage, was used as a control (T1), while each of the other four treatment diets (T2-T5) consisted of the selected bush species as roughage source at the same inclusion rate (40%) and the remaining portion (60%) consisted of the same combination of supplements. Batches of feed were mixed weekly and fed to the lambs. All treatment diets were formulated to meet nutrient requirements of growing sheep according to NRC (2007) recommendations.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eIngredients composition of the five treatment diets\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003eTreatment diets*\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFeed ingredient (kg \u0026ldquo;as is\u0026rdquo;)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eT1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCoarsely ground grass hay\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCoarsely ground lucerne hay\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMilled Bush\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYellow maize meal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMolasses syrup\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHPC 30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e32\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFutterfos\u0026trade; P14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCoarse salt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e* \u003cem\u003eT1\u003c/em\u003e control diet, \u003cem\u003eT2 Senegalia mellifera-\u003c/em\u003ebased diet, \u003cem\u003eT3 Dichrostachys cinerea\u003c/em\u003e-based diet, \u003cem\u003eT4 Terminalia sericea-\u003c/em\u003ebased diet and \u003cem\u003eT5 Rhigozum trichotomum\u003c/em\u003e-based diet; \u003cem\u003eHPC 30\u003c/em\u003e high protein concentrate with 30% crude protein; \u003cem\u003eFuttterfos\u0026trade;\u003c/em\u003e P14- Phosphate lick with 14% Phosphorus.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eExperimental animals and management\u003c/h3\u003e\n\u003cp\u003eThirty (30) weaned 3-month old Damara lambs (15 males and 15 females) with a mean weaning weight of 16.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9 kg were used. The lambs were vaccinated with Multivax P\u0026trade; (Intervet International B.V., The Netherlands) at the beginning of the trial to protect them against botulism, black quarter, pulpy kidney and clostridium. They were also treated with Dectomax\u0026trade; (Pfizer Laboratories (Pty) Ltd, Sandton) against internal and external parasites.\u003c/p\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eExperimental design and data collection\u003c/h2\u003e \u003cp\u003eThe experiment was set up as a completely randomized design (CRD) with six (6) lambs per treatment (3 males and 3 females), to evaluate feed intake (FI) and the growth performance for 90 days, after an adaptation period of 14 days. The 30 lambs were randomly allocated to the 5 dietary treatments and housed individually in pens of 1 m\u003csup\u003e2\u003c/sup\u003e with concrete floors in an open-sided roofed shed, where they received treatment diets and water on an \u003cem\u003ead lib\u003c/em\u003e basis.\u003c/p\u003e \u003cp\u003eAfter the adaptation period, the feed offered and feed refused daily were weighed and recorded to determine the feed intake. The daily feed was offered to each sheep in two portions, at 09h00 and 14h00. Initial body weights were obtained by weighing the lambs using an electronic scale (Micro T7E Scale; Premier Scale Services (Pty) Ltd) at the beginning of the adaptation period. Thereafter, the lambs were weighed weekly on the same day of the week in the morning before feeding, until the end of the experiment. Average daily gain (ADG) was calculated as difference between final and initial body weights divided by number of feeding days.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eSampling and chemical composition analysis of experimental diets\u003c/h2\u003e \u003cp\u003eDuring the trial period, random samples of each treatment diet were taken once from a weekly batch, mixed and pooled separately in marked paper bags. At the end of the experiment period, all treatment diet samples were ground to pass through a 1 mm sieve (Retsch Mable mill; Retsch GmbH) and stored in plastic bottles for chemical analysis. The dry matter (DM) content of bush species samples was determined by drying the samples in a forced draught oven at 100\u0026deg;C for 24 h (AOAC, 2000). Ash was determined by incineration in a muffle furnace at 550\u0026deg;C for 6 h (AOAC, 2000). The crude protein (CP) method no. 978.04 (AOAC, 2005) was used to determine the total nitrogen content and CP was estimated by multiplying percentage of N content by a factor 6.25. Ether extract (EE) was determined using the AOAC method 920.39 (AOAC, 2000). Ash-free neutral detergent fibre (NDFom) and Ash-free acid detergent fibre (ADFom) were determined following the procedures of Mertens \u003cem\u003eet al\u003c/em\u003e. (2002) with NDFom assayed without use of an alpha-amylase, but with sodium sulfite. Ash-free Acid detergent lignin (ADLom) was determined by placing dried ADF samples in 72% sulphuric acid (H\u003csub\u003e2\u003c/sub\u003eSO\u003csub\u003e4\u003c/sub\u003e) (Mertens, 2015). Calcium and Phosphorus were determined using inductively coupled plasma atomic emission spectrometry (Sah and Miller, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e1992\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eSlaughtering procedures\u003c/h2\u003e \u003cp\u003eAt the end of the feeding experiment, all sheep were individually weighed to obtain the final weight (FW), after being fasted overnight, with only access to water, to avoid digesta contamination. They were then transported to the Neudamm abattoir for slaughter. Sheep were slaughtered in accordance with the prescribed animal ethics and welfare regulations, at the registered abattoir facilities of the Neudamm campus, under the required conditions for local abattoirs in Namibia. Animals were stunned to render them unconscious and to ensure that they did not suffer pain during slaughter. After stunning, sheep were slaughtered by cutting the carotids, jugular vein, oesophagus and trachea to allow blood to drain from the carcass. The carcasses were hanged on the bleeding rail and the dressing operation began after the bleeding process was completed. All slaughtering procedures were done under the supervision of a veterinarian, specialized in Veterinary Public Health.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eCarcass characteristics\u003c/h2\u003e \u003cp\u003e After dressing and evisceration procedures, carcasses grading was done visually according to the South African Meat Classification System for beef, lamb, mutton and chevon, according to the Government Notice No. R.863 of 1 September 2006 (Republic of South Africa, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2006\u003c/span\u003e), which is also adopted by the Meat Board of Namibia. The carcasses were weighed to obtain hot carcass weights (HCW). The pH of the carcasses was measured 1 hour (pH\u003csub\u003e1\u003c/sub\u003e) after slaughter in the left \u003cem\u003eMusculus longissimus dorsi\u003c/em\u003e at the area between 10th to 13th rib, using a portable digital pH meter with a penetration electrode and temperature probe. Subsequently, carcasses were chilled in a cooler under the temperature of 2\u0026ndash;4\u0026deg;C for 24 hours to obtain the cold carcass weights (CCW). Cold carcass weight (CCW) was expressed as a proportion of the live weight at slaughter (SW) to determine the dressing percentage (Van der Merwe et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). The pH reading of the carcasses was taken again at 24 hours (pH\u003csub\u003e24\u003c/sub\u003e) in the \u003cem\u003eMusculus longissimus dorsi\u003c/em\u003e on the same spot where pH1 was taken. After 24 hours of chilling, the carcasses were then split into two halves down the spinal column by a longitudinal cut on the vertebral column using a meat band saw. The left side of the carcass was used for further measurements such as external length (CEL) of each carcass, shoulder and buttock circumferences (SC and BC, respectively), which were measured with a flexible tape measure following the procedure described by De Boer et al. (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e1974\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe fat thickness was measured at \u0026frac14; (Fat Pos\u0026frac14; ), \u0026frac12; (Fat Pos\u0026frac12; ) and \u0026frac34; (Fat Pos\u0026frac34;) positions on the 12th rib from the chine bone end, with a vernier calliper and from these, average fat thickness was calculated (Lima \u003cem\u003eet al.\u003c/em\u003e, 2015; Ara\u0026uacute;jo et al., 2017). The eye-rib depth and the eye-rib width of the \u003cem\u003eMusculus longissimus dorsi\u003c/em\u003e exposed by cutting the carcass between the 12th and 13th ribs were measured with a Vernier calliper (Ferreira \u003cem\u003eet al\u003c/em\u003e., 2012; Landim \u003cem\u003eet al\u003c/em\u003e., 2015). As per the method described by Ferreira \u003cem\u003eet al\u003c/em\u003e. (2012), the area of \u003cem\u003eMusculus longissimus dorsi\u003c/em\u003e was determined by measuring the maximal width of the muscle, denoted as \u0026ldquo;A\u0026rdquo; and its maximal depth \u0026ldquo;B\u0026rdquo; and then applying the values into the following equation: (A/2 \u0026times; B/2) \u0026times; \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\pi\\)\u003c/span\u003e\u003c/span\u003e, where \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\pi\\)\u003c/span\u003e\u003c/span\u003e equals to 3.1416. The three-rib cut was weighed and physically separated by blunt dissection into bone, lean and fat tissue which were weighed individually and expressed as a proportion of the cut as described by Van der Merwe et al. (\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eThe chemical composition of the diets was subjected to analysis of variance (ANOVA) using Proc GLM (SAS, 2009). Similarly, FCR and ADG were subjected to analysis of variance (ANOVA) using Proc GLM (SAS, 2009) with the effects in the model being sex and treatment.\u003c/p\u003e \u003cp\u003eIntake is a function of the body weight (W) of the animal, hence analyses were based on metabolic body weight (W\u003csup\u003e0.75\u003c/sup\u003e). The model (1) included the effects: sex, treatment, week and treatment x week interactions. Data was analysed using Proc Mixed (SAS, 2009) which takes into account correlation between repeated measures on an individual and the Bayesian Information Criterion (BIC) which compares covariance structures based on goodness of fitness criteria, was used to select the appropriate covariance structure (Littell et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e1998\u003c/span\u003e), which was simple. Estimate statements were used in Proc Mixed (SAS, 2009) to compare means and obtain standard errors. Effects were considered significant at P\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003cp\u003eY\u003csub\u003eijkl\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;\u0026micro;\u0026thinsp;+\u0026thinsp;F\u003csub\u003ei\u003c/sub\u003e + S\u003csub\u003ej\u003c/sub\u003e+ W\u003csub\u003ek\u003c/sub\u003e + FW \u003csub\u003eik\u003c/sub\u003e + e\u003csub\u003eijkl\u003c/sub\u003e (1)\u003c/p\u003e \u003cp\u003eWhere: Y\u003csub\u003eijkl\u003c/sub\u003e = feed intake; \u0026micro;\u0026thinsp;=\u0026thinsp;overall mean; F\u003csub\u003ei\u003c/sub\u003e = effect of treatment (i\u0026thinsp;=\u0026thinsp;T1, T2\u0026hellip; T5); S\u003csub\u003ej\u003c/sub\u003e = effect of sex (j\u0026thinsp;=\u0026thinsp;male, female); W\u003csub\u003ek\u003c/sub\u003e = effect of week (k\u0026thinsp;=\u0026thinsp;1,2,3\u0026hellip;13); FW \u003csub\u003eik\u003c/sub\u003e = interaction effect between treatment and week; e\u003csub\u003eijkl\u003c/sub\u003e = random error term explaining variation among experimental units (EU) on the same treatment.\u003c/p\u003e \u003cp\u003eA similar model to (1) was used to fit body weights, but with the additional interaction effect of treatment by sex. The best covariance structure for body weights was ante-dependence [ANTE(1)].\u003c/p\u003e \u003cp\u003eThe data on carcass characteristics were subjected to analysis of variance (ANOVA) using the General Linear Model (GLM) procedure (SAS, 2009). The effects in the model were treatment (T1-T5), sex and their interactions. Data were checked for normality and transformation was carried out where necessary, before statistical analysis. Means were separated using the Turkeys\u0026rsquo; Studentised range test.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eChemical composition of treatment diets\u003c/h2\u003e \u003cp\u003eThe chemical composition of the treatment diets used in this study is shown in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. The crude protein (CP) for T1 was similar to T2 but higher (P\u0026thinsp;=\u0026thinsp;0.03) than T3, T4 and T5, which did not differ (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05). The neutral detergent fibre (NDFom) and acid detergent fibre (ADFom) contents for T3 were higher (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01) than those of the other four treatment diets. Diet T1, however, had the lowest ADFom, while T4 and T5 had the lowest NDFom content. Diet T1 also had lower (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01) acid detergent lignin (ADLom) content compared to the bush-based diets.\u003c/p\u003e \u003cp\u003eThe ether extract (EE) content was higher (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01) in T3 and T4 among the bush-based diets, but T1 had the lowest content amongst all the treatment diets. Diets T4 and T2 had higher calcium content than T1, T3 and T5 which were similar (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eChemical composition (g/kg DM) of the five treatment diets\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003eTreatment diets*\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eT1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSEM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDry matter (DM)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e910\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e903\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e918\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e890\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e904\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOrganic matter (OM)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e869\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e890\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e904\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e869\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e885\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCrude protein (CP)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e146\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e143\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e135\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e140\u003csup\u003ebc\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e139\u003csup\u003ebc\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNeutral detergent fibre (NDFom)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e415\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e422\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e506\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e386\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e386\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAcid detergent fibre (ADFom)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e221\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e226\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e365\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e245\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e240\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAcid detergent lignin (ADLom)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e44.3\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e73.3\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e93.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e93.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e84.1\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEther extract (EE)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16.0\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16.8\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e19.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e20.0\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e17.5\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAsh\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e131\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e110\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e96\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e131\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e115\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCalcium (Ca)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.3\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9.6\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e13.2\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9.7\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePhosphorus (P)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.507\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.475\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.410\u003csup\u003ee\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.570\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.530\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMetabolizable energy (MJ/kg)\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e8.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eN/A\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eN/A\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"8\"\u003e* \u003cem\u003eT1\u003c/em\u003e control diet, \u003cem\u003eT2\u003c/em\u003e\u0026thinsp;=\u0026thinsp;\u003cem\u003eSenegalia mellifera-\u003c/em\u003ebased diet, \u003cem\u003eT3 Dichrostachys cinerea\u003c/em\u003e-based diet,\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cem\u003eT4 Terminalia sericea-\u003c/em\u003ebased diet and \u003cem\u003eT5 Rhigozum trichotomum\u003c/em\u003e-based diet\u003c/p\u003e \u003cp\u003e \u003csup\u003e1\u003c/sup\u003eEstimated metabolizable energy (ME) values; \u003cem\u003eSEM\u003c/em\u003e Standard error of means; N/A\u0026thinsp;=\u0026thinsp;not applicable; \u003csup\u003e\u003cb\u003ea \u0026minus; d\u003c/b\u003e\u003c/sup\u003eMeans with different superscripts within a row differ \u003cb\u003e(\u003c/b\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.05\u003cb\u003e).\u003c/b\u003e\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eFeed intake\u003c/h2\u003e \u003cp\u003eThe average daily feed intake (ADFI) of the lambs (kg DM/kg W\u003csup\u003e0.75\u003c/sup\u003eper day) during the ninety (90) days feeding period was affected (P\u0026thinsp;\u0026lt;\u0026thinsp;.05) by sex, treatment, week and treatment * week interaction (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Averaged over the trial period, the ADFI of T1 exceeded (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) that of other treatments.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e* \u003cem\u003eT1\u003c/em\u003e control diet; \u003cem\u003eT2 Senegalia mellifera-\u003c/em\u003ebased diet; \u003cem\u003eT3 Dichrostachys cinerea\u003c/em\u003e-based diet;\u003c/p\u003e \u003cp\u003e \u003cem\u003eT4 Terminalia sericea-\u003c/em\u003ebased diet and \u003cem\u003eT5 Rhigozum trichotomum\u003c/em\u003e-based diet\u003c/p\u003e \u003cp\u003eThe ADFI generally increased from week 1 to week 6\u0026ndash;7 and then stabilized, although lowest intake was for T2 and T3, which also showed the greatest lag. The ADFI for T1 exceeded (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) that for T2, T3 and T5, at most time points. Other than at weeks 3, 4, 5, 11 and 13, ADFI for T1 and T4 did not differ (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05). The ADFI of diets T2 and T3 were similar (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05) except at week 8. The ADFI of T4 exceeded (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) that of T2 and T3 at most time points. ADFI of T5 exceeded (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) that of T3 from weeks 4 to 10.\u003c/p\u003e \u003cp\u003eFrom estimated contrasts, the ADFI of the control diet appears to have peaked at week 6 where it plateaued. The ADFI for diets T2, T3, T4 and T5 reached their maximum at week 7 where they remained stable. The least squares mean (\u0026plusmn;\u0026thinsp;S.E) (kg) for ADFI of females exceeded (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) that for males (0.121\u0026thinsp;\u0026plusmn;\u0026thinsp;0.001 vs. 0.118\u0026thinsp;\u0026plusmn;\u0026thinsp;0.001)\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eGrowth performance\u003c/h2\u003e \u003cp\u003eThe live weights were influenced (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) by week, treatment * week and treatment * sex interactions. Figure\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows the least squares means of body weights for lambs on the different diets. The body weights increased linearly, but with fluctuations by diet. Only T2 body weights exceeded (P\u0026thinsp;=\u0026thinsp;0.04) those of T4 at week 13. The control diet (T1) did not differ (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05) from other treatments.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e* \u003cem\u003eT1\u003c/em\u003e conventional feedlot diet, \u003cem\u003eT2 Senegalia mellifera-\u003c/em\u003ebased diet, \u003cem\u003eT3 Dichrostachys cinerea\u003c/em\u003e-based diet, \u003cem\u003eT4 Terminalia sericea-\u003c/em\u003ebased diet and \u003cem\u003eT5 Rhigozum trichotomum\u003c/em\u003e-based diet\u003c/p\u003e \u003cp\u003eThe least squares means for growth performance are shown in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. With the exception of diet T4, there were no differences (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05) in live weights between males and females within in each treatment diet; females on T4 were heavier (P\u0026thinsp;=\u0026thinsp;0.0001) than males. The ADG and FCR were affected (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) by sex and treatment. Treatment T2 gave higher (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) ADG than other treatments. The least squares means for ADG (g/day) were 124.9\u0026thinsp;\u0026plusmn;\u0026thinsp;4.3 for females and 153.5\u0026thinsp;\u0026plusmn;\u0026thinsp;4.3 for males. Treatment T2 had a better (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) FCR compared to other bush-based treatments (T3, T4 and T5), but did not differ (P\u0026thinsp;=\u0026thinsp;.098) from the control (T1). The FCR for T3, T4 and T5 were also similar (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05) to the control (T1). The FCR for females was 9.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3 and for males was 8.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eLeast squares means (\u0026plusmn;\u0026thinsp;SEM) of growth variables for Damara lambs fed five diets from different roughage sources\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003eTreatment diets*\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eT1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSEM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInitial weight (kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e16.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e17.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.56\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFinal weight (kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e28.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e28.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e29.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.43\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal gain (kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e12.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e12.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.24\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e#Average daily gain (g/day)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e148.0\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e156.4\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e124.2\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e133.7\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e133.7\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt; 0.05\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e#Feed conversion ratio\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.8\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.6\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9.5\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.6\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9.4\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt; 0.05\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e#Body weights (kg) for males\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23.4\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.9\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e23.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e19.8\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e23.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e#Body weights (kg) for females\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22.7\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.8\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e22.7\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e25.0\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e23.8\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"8\"\u003e* \u003cem\u003eT1\u003c/em\u003e control diet, \u003cem\u003eT2 Senegalia mellifera-\u003c/em\u003ebased diet, \u003cem\u003eT3 Dichrostachys cinerea\u003c/em\u003e-based diet, \u003cem\u003eT4 Terminalia sericea-\u003c/em\u003ebased diet and \u003cem\u003eT5 Rhigozum trichotomum\u003c/em\u003e-based diet; \u003csup\u003e\u003cb\u003ea \u0026minus; d\u003c/b\u003e\u003c/sup\u003eMeans with different superscripts within a row differ \u003cb\u003e(\u003c/b\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.05\u003cb\u003e).\u003c/b\u003e # Least squares means; \u003cem\u003eSEM\u003c/em\u003e Standard error of means\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eCarcass characteristics\u003c/h2\u003e \u003cp\u003eThe final weight (FW) and carcass characteristics results are presented in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e. The lambs from all five treatment groups visually scored similarly (score 1) in terms of subcutaneous fat cover, and they all fell under the same carcass grade A1. Treatment did not influence (P\u0026thinsp;=\u0026thinsp;0.09) hot carcass weight (HCW). The FW, HCW and cold carcass weight (CCW) were influenced (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) by sex. Irrespective of the treatment diet, the FW, HCW and CCW were lighter (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) for female than male lambs, while the dressing percentage did not differ (P\u0026thinsp;=\u0026thinsp;0.09) by sex.\u003c/p\u003e \u003cp\u003eNone of the effects were significant (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05) for: carcass yield; average subcutaneous fat thickness and fat thickness taken at three different positions over the \u003cem\u003eMusculus longissimus dorsi\u003c/em\u003e (the rib-eye muscle); pH\u003csub\u003e24\u003c/sub\u003e; carcass lean; carcass external length (CEL); buttock circumference (BC); and rib-eye width. Treatment diets affected (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) rib-eye area (REA). Lambs on treatments T1 and T5 had lower (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) rib eye area (REA) than those on T4. The pH\u003csub\u003e1\u003c/sub\u003e values were influenced (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) by treatment. Lambs on treatment T5 had higher (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) pH\u003csub\u003e1\u003c/sub\u003e values than those on other treatments.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSlaughter weight and carcass characteristics least squares means (\u0026plusmn;\u0026thinsp;SEM) of the Damara lambs fed different diets\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"11\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"5\" nameend=\"c6\" namest=\"c2\"\u003e \u003cp\u003eTreatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003eSex\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003eP values\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eT\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT4\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eT5\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eM\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003eTreatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSex\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCarcass grade\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eA1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eA1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eA1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eA1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eA1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFW (kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30.6\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e28.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e28.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e29.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e28.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e30.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.05\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHCW (kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e11.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e11.5\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e11.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.2\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e12.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.2\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCCW (kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e10.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e11.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e11.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.2\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e11.6\u0026thinsp;\u0026plusmn;\u0026thinsp;0.2\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.05\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCCD (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e38.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e37.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e38.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e37.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e39.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e37.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.09\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCEL (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e56.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e54.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e54.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e54.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e54.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e54.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e55.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.65\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSC (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e21.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e20.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e21.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e21.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e21.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.48\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBC (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e34.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e35.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e35.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e34.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e35.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e34.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e34.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.91\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003epH\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.6\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e6.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e5.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e5.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.74\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003epH\u003csub\u003e24\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e5.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e5.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e5.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.86\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.28\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFat_1(mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.6\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e2.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3.5\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e2.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.12\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFat_2 (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.5\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e1.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e2.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.59\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFat_3 (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e2.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e2.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.30\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAvg fat (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e2.4\u0026thinsp;\u0026plusmn;\u0026thinsp;03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e2.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.13\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRib eye-width (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.5\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e4.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e4.5\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e4.5\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e4.6\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.51\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRib eye-depth (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e1.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRib eye area (cm\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e8.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e6.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.038\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e* \u003cem\u003eT1\u003c/em\u003e control diet, \u003cem\u003eT2 Senegalia mellifera-\u003c/em\u003ebased diet, \u003cem\u003eT3 Dichrostachys cinerea\u003c/em\u003e-based diet, \u003cem\u003eT4 Terminalia sericea-\u003c/em\u003ebased diet and \u003cem\u003eT5 Rhigozum trichotomum\u003c/em\u003e-based diet. \u003cem\u003eFW\u003c/em\u003e Final weight; \u003cem\u003eHCW\u003c/em\u003e hot carcass weight; \u003cem\u003eCCW\u003c/em\u003e cold carcass weight; \u003cem\u003eCCD\u003c/em\u003e cold carcass dressing; \u003cem\u003eCEL\u003c/em\u003e carcass external length; \u003cem\u003eSC\u003c/em\u003e shoulder circumference; \u003cem\u003eBC\u003c/em\u003e buttock circumference; \u003cem\u003eSEM\u003c/em\u003e standard error of the mean; \u003cem\u003eF\u003c/em\u003e Female; \u003cem\u003eM\u003c/em\u003e Male. \u003csup\u003e\u003cb\u003eab\u003c/b\u003e\u003c/sup\u003eMeans with different superscripts within a row differ \u003cb\u003e(\u003c/b\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.05\u003cb\u003e).\u003c/b\u003e\u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eChemical composition of treatment diets\u003c/h2\u003e \u003cp\u003eIt is a general practice to include a minimum amount of roughage in high-concentrate feedlot diets to maintain rumen health and reduce digestive disorders (Mertens, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2002\u003c/span\u003e). According to Jolly and Wallace (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2007\u003c/span\u003e), ruminants appear to differ in their minimum fibre requirements; sheep in particular require a minimum of 10% roughage in the diet. However, in this study, all diets contained 40% roughage from different sources. Mertens (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2002\u003c/span\u003e) cautioned against feeding an excessive amount of fibre because it can increase rumen fill and reduce the dry matter intake (DMI), which subsequently also reduces animal growth.\u003c/p\u003e \u003cp\u003eIn this study, the NDF contents of the diets were 50% or below and was lower than the concentration suggested (60\u0026ndash;65%) to limit intake and digestibility of nutrients in ruminants (Van Soest et al., \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e1991\u003c/span\u003eb). Similarly, Van de Vyver et al. (\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2014\u003c/span\u003e) also used feedlot diets for lambs with the NDF contents ranging from 24.3\u0026ndash;42.1%, where Lucerne hay was replaced with different inclusion levels of maize silage as a roughage source. The NDF contents of the five treatment diets used in this study (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) were, however, higher than the recommended range of 15 to 20% NDF by Smith (\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2008\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003eFeed intake\u003c/h2\u003e \u003cp\u003eFeed intake is a major factor that influences the amount of nutrients available to the lamb in order to realise its growth potential (van der Merwe et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). A key concern of high proportions of roughage in feedlot rations is the high NDF content, which may physically restrict the dry matter intake through rumen fill (Jolly and Wallace, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2007\u003c/span\u003e; Oba and Allen, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e1999\u003c/span\u003e). Intake is a function not only of the NDF concentration, but also of the source of fibre (Ruiz et al., \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e1995\u003c/span\u003e), which partly explains the variability in intake of diets formulated from different roughage sources. Notwithstanding the 2-week adjustment period, the feed intake increased from week 1 to 6 for all treatments, which may indicate a gradual adjustment of the rumen microbes to the diets. Hence animals may require a longer adjustment period (6\u0026ndash;8 weeks) in feeding trials involving highly fibrous diets (40%) as implemented in this study. Mapiye et al. (\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2009\u003c/span\u003e) also suggested a longer adjustment period for cattle supplementation diets formulated using \u003cem\u003eAcacia karroo\u003c/em\u003e leaf-meal due to the low diet palatability. Peak ADFI was attained earlier at 6 weeks for T1 compared to 7 weeks for T2 \u0026ndash; T5, which may be explained by the higher ADFom and ADLom in bush-based diets requiring a longer adaptation period for the rumen microbes.\u003c/p\u003e \u003cp\u003eThe ADFI was affected by treatment * week interactions, which may be partly due to the inevitable variation in the supplied feed caused by natural variability by batch in the ingredients particularly for the bush material, which was harvested from different farms and over varying terrain and soils that ultimately may affect the physical and chemical characteristics of the diets. Flores-mar et al. (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) replaced alfalfa hay with sorghum straws as roughage source and obtained similar dry matter intake when diets were formulated to contain the same percentage of forage NDF. This was not the case in the current study, as the diets were only formulated to contain similar inclusion levels of roughage sources but not the NDF content.\u003c/p\u003e \u003cp\u003eThe digestibility coefficients for DM, OM, CP, NDFom and ADFom for T1 generally exceeded those for other treatments (Shiningavamwe, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2022\u003c/span\u003e), which may have contributed to higher ADFI for T1 compared to the bush-based diets. Treatments T4 and T5 had lower NDFom compared to T2 and T3, which possibly contributed to a faster rate of digestion, hence reducing rumen fill. Other factors including high palatability and high passage rate (Jolly and Wallace, 2017) may have contributed to the greater intake of T4 and T5 than T2 and T3. Worthy noting is the considerable feed wastage due to the sorting behaviour when feeding lambs observed during the trial, which was solved earlier in the trial by addition of water (200 ml) to the feed, which helped in binding the feed ingredients, hence reducing the sorting and selection of feed components.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec18\" class=\"Section2\"\u003e \u003ch2\u003eGrowth performance\u003c/h2\u003e \u003cp\u003eThe non-significant contrasts of body weights for sheep on the control diet versus the rest of the diets across the 13 weeks, is surprising given that bush-based diets on account of their higher ADFom and ADLom (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), should have restricted intake and hence body weight gains. This result, however, implies the equivalence of bush-based diets to grass hay in conventional diets in serving as a roughage source for moderate live weight gains. Superior performance on T2 compared to other diets may be attributed to the higher metabolizable energy content, high nutrients digestibility and a better amino acid profile (Shiningavamwe, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eUnlike the body weights which were affected by treatment x week and treatment x sex interactions, ADG and FCR are summary measures that provide aggregate performance and may mask the inherent fluctuations and subtle differences among animals under different treatments. The differences in growth rates of males and females lambs observed in this study among the different treatment diets were similar to the observations by Rodr\u0026iacute;guez et al. (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2008\u003c/span\u003e) in a fattening study on Assaf lambs, which was partly associated with dietary selection by animals of different sex. These authors found that the growth rates were lower in females than in males which were linked to similar trends in their dry matter and crude protein intake.\u003c/p\u003e \u003cp\u003eAccording to van der Merwe et al. (\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), for profitable production, producers often aim for an ADG of 300 g/day and FCR of 5.0 kg feed/kg weight gain, depending on the breed and type of feed used in the finishing system. In this study, the best ADG (156.4\u0026thinsp;\u0026plusmn;\u0026thinsp;6.9 g/day) and FCR (7.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5) were obtained with T2, which were far more inefficient than the proposed figures above. The poorer performance for ADG and FCR in the present study could be related to the high inclusion rate of low-quality roughage sources than most conventional feedlot diets, which usually contain 20% or less roughage. Ismail and Obeidat (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2023\u003c/span\u003e) who used Awassi lambs with a 25% roughage diet of wheat straw and olive leaves obtained ADG in the range of 218 to 235 g/day and FCR in the range 4.19 to 4.52. Van de Vyver et al. (\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2014\u003c/span\u003e) who replaced lucerne hay with maize silage as roughage source, reported similar FCR to T1 and T2 in this study. As indicated above, however, this level of FCR is not optimal for the production of sheep in a feedlot. Therefore, future research is warranted to optimize these diets to specification levels for growing lambs in the feedlot, with special focus on inclusion levels of each encroacher species depending on their physical and chemical fibre characteristics. There may also be a need to chemically or enzymatically treat bush-based feeding material so as to improve nutrient utilization (Adesogan et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2019\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec19\" class=\"Section2\"\u003e \u003ch2\u003eCarcass characteristics\u003c/h2\u003e \u003cdiv id=\"Sec20\" class=\"Section3\"\u003e \u003ch2\u003eCarcass classification\u003c/h2\u003e \u003cp\u003eCarcass classification systems were developed to inform processors and consumers about the quality of the carcass and thus to distinguish its market value (Brand et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). In the present study, all carcasses of the Damara lambs in the five treatment diets fell in the same age category (A: with no permanent incisors) and fatness score 1, which gave an overall A1 grade. The age category was expected to be similar since they were all born within the same lambing season. The A1 grading could be explained by the fact that Damara sheep are fat-tailed and much of the body fat is accumulated around the tail with minor fat deposits in the rest of the body (Kleemann et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2000\u003c/span\u003e; Tshabalala et al., \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2003\u003c/span\u003e; Almeida, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2011\u003c/span\u003e; Wilkes et al., \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2012\u003c/span\u003e; Almeida et al., \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). Therefore, this implies that the milled bush diets are good enough to produce lean meat.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec21\" class=\"Section2\"\u003e \u003ch2\u003eCarcass measurements\u003c/h2\u003e \u003cp\u003eFinal, hot carcass and cold carcass weights were heavier in males than females which is consistent with findings by Simela \u003cem\u003eet al\u003c/em\u003e. (2011) in goats and Van der Merwe et al. (\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) in lambs. Dressing percentage was in the range 37.4 to 40%, which is similar to what was reported in Menz sheep (Assefa et al., \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2008\u003c/span\u003e), but this falls far short of dressing percentage reported in other studies for example: 46.1\u0026ndash;48.3% (Cardoso et al., \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2021\u003c/span\u003e); 49.4\u0026ndash;50.2% (Rezaei et al., \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2013\u003c/span\u003e); 59.9% (Simela et al., \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2004\u003c/span\u003e). Dressing percentage is affected by live weight, fatness, time off water and feed, sex and breed (Warmington and Kirton, \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e1990\u003c/span\u003e). Higher growth rates have been typically associated with higher dressing percentages (Seoni et al., \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) and given that ADG in this study was in the range 124 to 156 g/day, the slower growth could have contributed to the lower dressing percentage. Wilkes et al. (\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2012\u003c/span\u003e) reported dressing percentage in Damara sheep of 53.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9%, which reflected greater fatness compared to Merino (dressing percentage\u0026thinsp;=\u0026thinsp;41.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8%). Results of this study suggest that while bush-based diets may be able to meet maintenance requirements, the inclusion rate used in this study might be high for supporting optimal growth in feedlots. Further studies are needed to determine optimal inclusion levels of browse material in feed rations and to determine whether chemical or biological treatment may improve their utilization.\u003c/p\u003e \u003cp\u003eThe pH\u003csub\u003e1\u003c/sub\u003e for T5 was slightly higher compared to other treatments which may be attributed to low muscle glycogen reserve possibly due to low energy supply (Vestergaard et al., \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2000\u003c/span\u003e). Although the diets were formulated to be iso-energetic, diet T5 had the lowest DM and OM digestibility (Shiningavamwe, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) which could have contributed to low energy reserves. It was, however, observed that the ultimate pH\u003csub\u003e24\u003c/sub\u003e was similar for the different diets. Dietary energy intake impacts muscle glycogen reserves (Daly et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2006\u003c/span\u003e; De Brito et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2016\u003c/span\u003e) and these in turn affect muscle pH values. This implies that the observed similar ultimate pH could be attributable to a different factor not muscle glycogen reserves as influenced by dietary energy levels. Muscle pH values affect colour, water-holding capacity and sensory attributes of lamb meat (Ferguson and Gerrard, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). In this study muscle glycogen reserves were not determined and neither was the eating quality assessed but these would be useful in future studies to determine effects of different bush-based diets on meat sensory attributes.\u003c/p\u003e \u003cp\u003eRib eye area (REA) is associated with the amount of muscle in a carcass and is indicative of muscle development and yield of high value cuts (Williams, \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e2002\u003c/span\u003e). The results indicate greater muscle development for animals on diets T2, T3 and T4 compared to T1 and T5; similarly rib eye depth was greater in T4 than T1. Even after adjusting for differences in CCW, the advantage of T4 over T1 and T5 were still evident for both rib eye depth and REA. It is not clear why the T4 diet could have positively influenced muscling without impacting ADG.\u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThe milled bush of the four-encroacher species can be used to partially replace grass and Lucerne hay in diets for weaned lambs. Lambs fed T2 had higher ADG and better FCR than other treatment groups, but still fell short of targets for commercial sheep feedlots, probably due to low nutrient digestibility of the bush roughage sources. The lambs fed the bush-based diets had carcass characteristics that were comporable to those on the control diet. Cold carcass weights, grading, ultimate pH and fat thickness were similar among treatments. Although encroacher bush could be used to partially substitute grass hay, the low dressing percentage possibly related to slow growth rates is of particular concern because it impacts profitability. Therefore, more research is needed to develop efficient feeding strategies or processing such as pelletizing, that encourage inclusion of milled bush as roughage source for ruminants.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements.\u003c/strong\u003e The first author is grateful for financial support to her studies by the Finnish Embassy in Namibia through the Bush\u0026ndash;to-Feed Project implemented by the University of Namibia. We would also like to thank the Ministry of Agriculture, Water and Land Reform (MAWLR) for granting a full-time study leave and research support to SKL. The University of Namibia is also thanked for the additional support in carrying out the research.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contribution\u003c/strong\u003e: Shiningavamwe Katrina Lugambo conceptualized the study, carried out the trials and wrote the initial draft of the manuscript. Lutaaya Emmanuel co-supervised the first author, advised on the experimental design, carried out statistical analysis, revised the draft manuscript. Mupangwa Johnfisher was the main supervisor to the first author; gave general oversight for the study; review and editing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability.\u003c/strong\u003e The datasets generated for the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval\u003c/strong\u003e.\u0026nbsp;This research was approved by the University of Namibia Research Ethics Committee (UREC) (AREC/024/2020).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e. The\u0026nbsp;Finnish Embassy in Namibia through the Bush\u0026ndash;to-Feed Project implemented by the University of Namibia\u0026nbsp;provided funding support to SKL.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest.\u003c/strong\u003e The authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAdesogan A., Arriola, K., Jiang Y., Oyebade A., Paula, E., Pech-Cervantes, A., Romero, J., Ferraretto, L. and Vyas, D., 2019. \u003cem\u003eSymposium review: Technologies for improving fiber utilization\u003c/em\u003e. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.3168/jds.2018-15334\u003c/span\u003e\u003cspan address=\"10.3168/jds.2018-15334\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAlmeida, A. M, Kilminster, T., Scanlon, T., Araujo, S. 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Journal of Animal Science, 80 (E-Suppl_2), E 183 \u0026ndash; E188. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.2527/animalsci2002.80e-suppl_2e183x\u003c/span\u003e\u003cspan address=\"10.2527/animalsci2002.80e-suppl_2e183x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"tropical-animal-health-and-production","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"trop","sideBox":"Learn more about [Tropical Animal Health and Production](https://www.springer.com/journal/11250)","snPcode":"11250","submissionUrl":"https://submission.nature.com/new-submission/11250/3","title":"Tropical Animal Health and Production","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"bush encroachment. average daily gain. finishing rations. feed resources. carcass characteristics","lastPublishedDoi":"10.21203/rs.3.rs-4241387/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4241387/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe effect of feeding bush-based finishing rations on the performance of Damara lambs was studied. Thirty weaned lambs weighing 16.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9 kg were allocated to five treatments in a completely randomized design over a 90-day feeding period. The control diet (T1), consisted of Lucerne (10%), grass hay (30%) and concentrate mix (60%). Treatments T2-T5 consisted of roughage (40%) from the milled bushes \u003cem\u003eSenegalia mellifera, Dichrostachys cinerea, Terminalia sericea\u003c/em\u003e and \u003cem\u003eRhigozum trichotomum\u003c/em\u003e respectively, and concentrate mix (60%). At the end of the feeding trial, the lambs were slaughtered and carcass characteristics were evaluated. The average daily feed intake (ADFI) was affected (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) by sex, treatment, week and treatment x week interactions. The ADFI for T1 exceeded (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) that for T2 and T3, at most time points. The ADFI of T1 and T4 were similar (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05) at weeks 6 to 10, but differed (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) at other time points. The average daily gain (ADG) and feed conversion ratio (FCR) were affected (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) by sex and treatment. The ADG (g/day) least squares means (\u0026plusmn;\u0026thinsp;S.E) for T1 \u0026ndash; T5 were 148.0\u0026thinsp;\u0026plusmn;\u0026thinsp;6.9, 156.4\u0026thinsp;\u0026plusmn;\u0026thinsp;6.9, 124.2\u0026thinsp;\u0026plusmn;\u0026thinsp;6.9, 133.7\u0026thinsp;\u0026plusmn;\u0026thinsp;6.9 and 133.7\u0026thinsp;\u0026plusmn;\u0026thinsp;6.9, respectively. Treatment T2 had a better (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) FCR compared to other bush-based treatments. Males had heavier (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) final, hot and cold carcass weights than females. Lambs fed T4 had greater (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) rib eye area than T1 (8.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5 vs. 5.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5 mm\u003csup\u003e2\u003c/sup\u003e). Bush-based diets can serve as production diets for weaned sheep and result into acceptable weight gain and carcass quality.\u003c/p\u003e","manuscriptTitle":"Feed intake, growth performance and carcass characteristics of Damara lambs fed bush-based rations from four encroacher bush species","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-05-14 19:16:52","doi":"10.21203/rs.3.rs-4241387/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Accept with minor revision","date":"2024-07-17T13:20:43+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2024-06-14T11:06:28+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-05-07T10:45:53+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-04-19T07:16:59+00:00","index":"","fulltext":""},{"type":"submitted","content":"Tropical Animal Health and Production","date":"2024-04-18T07:30:05+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"tropical-animal-health-and-production","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"trop","sideBox":"Learn more about [Tropical Animal Health and Production](https://www.springer.com/journal/11250)","snPcode":"11250","submissionUrl":"https://submission.nature.com/new-submission/11250/3","title":"Tropical Animal Health and Production","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"749fe5a9-2d64-4f42-aeab-bba122b7cc10","owner":[],"postedDate":"May 14th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-06-09T16:02:28+00:00","versionOfRecord":{"articleIdentity":"rs-4241387","link":"https://doi.org/10.1007/s11250-025-04473-w","journal":{"identity":"tropical-animal-health-and-production","isVorOnly":false,"title":"Tropical Animal Health and Production"},"publishedOn":"2025-06-04 15:57:30","publishedOnDateReadable":"June 4th, 2025"},"versionCreatedAt":"2024-05-14 19:16:52","video":"","vorDoi":"10.1007/s11250-025-04473-w","vorDoiUrl":"https://doi.org/10.1007/s11250-025-04473-w","workflowStages":[]},"version":"v1","identity":"rs-4241387","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4241387","identity":"rs-4241387","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}