Nutritional status and reproductive performance of cattle agroecosystems in silvopastoralism in the Andean region of Ecuador

Nutritional status and reproductive performance of cattle agroecosystems in silvopastoralism in the Andean region of Ecuador | 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 Nutritional status and reproductive performance of cattle agroecosystems in silvopastoralism in the Andean region of Ecuador Hernán Rigoberto Benavides Rosales, Luis Rodrigo Balarezo Urresta, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6856634/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The goal of this study was to find out how silvopastoral systems with Alnus acuminata H.B.K. (Alder) and Acacia melanoxylon R.Br. (Acacia) along with the herbaceous layer affect the nutritional status and reproductive performance of agroecosystems (AES) in Ecuador's Andean region with silvopastoral cattle. AES 1 and 2 contained alder and Acacia, respectively, and AES 3 contained grasses only. We determined the effect of AES and year on reproductive indicators and body condition at calving (BCC) using multifactorial ANOVA and interaction. There was an energy deficit in the second year in AES 1 and 3, and in all three years in AES 2. There was an excess of crude protein in all three AES in all three years. The first service parity interval (FPSI) was lower (P < 0.05) in AES 1 and in years 2 and 3. The CCP was higher (P < 0.05) in AES 1, and the services per gestation were higher (P < 0.05) in the first year. Calving-conception (CCP) and calving-delivery (DDP) intervals were lower in AES1 and in years two and three. We conclude that Alder and Acacia favored nutrient balance in AES 1 and 2. In AES 1, CCP was higher, and IPPS was reduced; the interaction between AES and the year of study benefited CPI and IPP, which were better in AES 1, in the third year. Silvopastoral systems Agroecosystems Body condition reproductive indicators Natality Figures Figure 1 Figure 2 Figure 3 Introduction Feeding of specialized cattle herds in the Andean region of Ecuador is based on extensive grazing, with a predominance of monoculture of tropical grasses and the absence of trees (Balarezo et al. 2018 ), like what happens in tropical areas of Latin America (Durand-Chávez et al. 2022 ). Under these conditions, soils are degraded, there is a low supply of shade, the quantity and quality of edible biomass are affected, and the bio-economic behavior of the animals is affected (Donaghy et al. 2022 ). In the agro-ecosystems (AES) of the Carchi province, dairy cows don't get enough of the nutrients they need. As a result, they have high levels of blood urea nitrogen (BUN) and beta hydroxybutyrate (B-OH) in their serum, as well as low levels of phosphorus, potassium, and phosphorous (Balarezo et al. 2018 ). All of these changes were linked to worsening reproductive indicators. La implementación de Sistemas Silvopastorales (SSP) es una alternativa para resolver problemas ecológicos causados por la ganadería extensiva (Amorim et al. 2023 ) y beneficiar la salud y producción animal (Buitrago et al. 2018; Wilkens et al. 2022 ; Thomsen et al. 2023 ; Poudel et al. 2024 ). In addition, these ESAs generate positive economic impacts through other marketable products or income diversification, reduce erosion, and benefit the environment (Amorim et al. 2023 ). SSPs generate positive interactions among their components, with better reproductive performance for the animals and less negative environmental impact (Benavides et al. 2019 ). In addition, they reduce the use of external inputs in agricultural SSAs (Tzec-Gamboa et al. 2023 ). Adding trees to the mix of soil, plants, and animals improves the nutritional value of the edible phytomass and the amount of DM and nutrients that are available to each animal every day. This lowers the nutritional deficit and, as a result, makes the cows healthier during labor and birth, and it also affects how they reproduce (Vargas-Hernández 2013 ). In addition, SSPs contribute to animal comfort by reducing heat stress, resulting in improved production cycles and improved diet quality (Viñoles et al. 2022 ). Cattle placed under shade feel more comfortable and have less caloric stress; therefore, they will consume feed for a longer time, which increases their productivity and improves reproductive parameters (Arciniegas-Torres and Flórez-Delgado 2018 ; Thomsen et al. 2023 ; Poudel et al. 2025 ). Silvopastoralism has many benefits, but most cattle producers don't use it because they don't know enough about it, don't have the resources to set up SSPs, and their animals' reactions vary from place to place because of differences in tree and pasture species, as well as soil and weather conditions (Poudel et al. 2021). The impact of the introduction of SSP on the nutrient balance and reproductive behavior of dairy herds using low external inputs in the Andean region of Ecuador is unknown. The point of this study was to look into what changes happen when you add SSP with Alnus acuminata H.B.K. (Alder) y Acacia melanoxylon R.Br. (Acacia), along with the herbaceous cover, to the nutritional status and reproductive performance of ganaderos in silvopastoralism in Ecuador's Andean region. Methods Research scenario and its edaphoclimatic conditions The research was carried out during the years 2020, 2021, and 2022 in dairy herds of the San Vicente farm, parish “El Carmelo,” Tulcán canton, Carchi province, Ecuador. The experimental area is in the hydrographic area 230, from latitude 0º39'33"N, longitude 77º36'20"W to latitude 0º38'55"N, longitude 77º36'25"W, with an altitude of 2916 to 3006 m.a.s.l. (INAMHI 2022 ). The research site is 54.4 ha. Its soil is in the Andisol order, whose MO, pH, water retention, and effective depth fluctuate between 10 and 25%, 5.5 and 6.5%, 20 and 100%, and 20 and 70 cm, respectively. The relief undulates with a slope percentage that fluctuates between 10 and 40%, and N2 varies from medium to high values. The main limiting factor of the soils of the Andean region of Ecuador is acidity (Benavides et al. 2019 ). La precipitación en los años del experimento varió de 892.50 a 1,317.50 mm. The average mean, maximum, and minimum temperatures during the study period were 12.12, 16.49, and 8.06°C, respectively (INAMHI 2022 ). Agro-ecosystem characteristics (AES) Three AES were used in a completely randomized experimental design. The predominant grasses in the three AES were Kikuyu (Pennisetum clandestinum L.), Ray grass (Lolium perenne L.), Holco (Holcus lanatus L.), and White clover (Trifolium repens L.). AES 1 (Fig. 1 ) was composed of grasses and A. acuminata trees, AES 2 (Fig. 2) of grasses and A. melanoxylon trees, and AES 3 of grasses only; the same was considered a control. Trees in AES 1 and AES 2 were established in December 2019, at a planting density of 1000 trees ha⁻¹, in double rows, two meters apart, following contour lines (Figs. 1 and 2). We established double electric fences to protect the young trees from cow damage, which also served to divide the quarters. The practices used to design and establish the AES are consistent with those used in other countries (Poudel et al. 2025 ). Time-restricted grazing was used for 18 hours per day. No protein energy concentrate was administered, but mineral salts were supplemented orally ad libitum. Mechanized milking of the cows was used twice a day, 5:00–7:00 am and 3:00–5:00 pm. The calf underwent artificial rearing from the third day of its birth. Animals involved Between 29 and 34 cows were used, and 9 to 12 cows were randomly assigned to each AES. The animals met the following criteria: Holstein cows between three and four years of age, with CC at calving (CCP) between 3.0 and 4.0 points on the five-point scale, were in third and fourth lactation with an average milk production of 10 ± 2 L cow⁻¹ day⁻¹, clinically healthy, not receiving medical treatment, and had an average milk production of 10 ± 2 L cow⁻¹ day⁻¹. Metodologies of work Health status General health status was determined at the beginning of the experiment and followed throughout the study, using the functional invariants of the clinical method (Cuesta et al. 2007 ). The animals were dewormed and vaccinated according to the area's schedule. Nutritional balance The nutritional balance was calculated according to the feed offered (pasture mix, mineral salt, and the foliage of the trees in the third year), the requirements of the cows, and the contribution of each year. In addition, the average annual PV, PV increase, potential and actual milk fat percentage, locomotion expense, feed consumed, and number of lactations were considered. For this calculation, he used the software developed by Roche et al. ( 1999 ). Indicators of reproductive performance and body condition We used the methods explained by Brito et al. ( 2010 ) to find out the birth index (NI), the percentage of gestations at first service, the services per gestation (S/G), the calving-first service interval (IPPS), the calving-conception interval (CPI), and the calving-calving interval (CPI). Estrus detection was performed between 5:00–9:00 am and 3:00–7:00 pm by a trained man, using paint at the base of the cows' tails as an auxiliary method. For artificial insemination, the semen was deposited in the uterus by an experienced technician, with a technical efficiency between 60 and 65% in the past four years. We used semen from Holstein bulls with proven fertility, which we contained in 0.25 c.c. straws at a concentration of 32 million per dose. Body condition (CC) was estimated by physical examination of the animals that included inspection and palpation, classifying it on a scale of 1–5 points and divisions of 0.25 between them according to the methodology proposed by Rodenburg ( 2004 ). Due to the limited number of animals in the AES under study, we only determined CC at calving (CCP). Statistical processing Multifactorial analysis of variance (multifactorial ANOVA) was used to find out how AES and year affected reproductive indicators (IPPS, IPC, IPP, and S/G) and CCP. Means were compared using the Bonferroni test (Bonferroni 1936 ). We compared the birth rate within each AES year and between years within the AES using a multiple comparison of proportions. We used the statistical package Statgraphics Centurion version XV for statistical processing (Statistical Graphic Corp., USA 2006). Results The energy requirements of the cows in AES 1 were met at 107.37 and 103.34% in the first and third years, while in the second year 97.72% of the requirements were met and there was a deficit of 2.28 MJ; on the other hand, in AES 2 there was an energy deficit of 9.62, 15.48, and 1.25 MJ in years 1, 2, and 3, in that order. In AES 3, the energy demands were covered, except in the second year, where only 96.72% of the demands were covered, and the animals had a deficit of 2.93 MJ. During the three years of the study, the crude protein requirements in all three AES exceeded their demands, ranging from 106.89–183.01%. Ca and P requirements were covered in all three AES and years between 100 and 152.35%. For the IPPS, there are significant differences (P < 0.05) between the AES, being lower in AES 1 (Table 1 ). Following the study, the voluntary waiting period (Brito et al. 2010 ) should not be longer than 18 days before the first service calving interval (IPPS). In the herds that were looked at, this was 45 days, so the postpartum anestrus period (PPA) was 64, 34, 87.09, and 134.77 days for AES 1, AES 2, and AES 3. Table 1 Comparison of mean reproductive indicators (S/G and IPPS) and body condition at calving (BCC). Source S/G IPPS (Days) CCP ߄ ± EE ߄ ± EE ߄ ± EE AES AES 1 (n = 21) 2,31 ± 0,17 a 127,34 ± 5,86 c 3,45 ± 0,07 a AES 2 (n = 20) 2,48 ± 0,17 a 150,09 ± 5,98 b 3,05 ± 0,07 b AES 3 (n = 17) 2,35 ± 0,19 a 197,77 ± 6,50 a 2,85 ± 0,08 b Year 1 (n = 17) 2,91 ± 0,19 a 174,94 ± 6,50 a 3,07 ± 0,08 a 2 (n = 20) 2,21 ± 0,17 b 147,99 ± 5,98 b 3,08 ± 0,07 a 3 (n = 21) 2,00 ± 0,17 b 152,28 ± 5,86 b 3,20 ± 0,07 a abc Different characters in the same column, within each source of variation, differ for P < 0.05, (Bonferroni 1936 ). Table 2 shows that the CPI and PPI differed (P < 0.05) between AES and years, being lower in AES1 and years two and three. The AES's interaction with the year clearly influenced the CPI and PPI. AES 1 had the best results in year three, AES 2 in years two and three without differences between them, and in AES 3 the year had no influence. This is since the year's influence on the establishment of the AES was revealed. Table 2 Comparison of CPI and PPI averages in the three SSAs and study years Source N IPC (Days) IPP (Days) ߄ ± EE ߄ ± EE AES AES 1 21 172,69 ± 8.89 c 469,54 ± 4,69 c AES 2 20 204,20 ± 9,07 b 484,01 ± 4,79 b AES 3 17 256,82 ± 9,85 a 536,98 ± 5,20 a Year 1 17 247,10 ± 9,85 a 538,32 ± 5,20 a 2 20 199,46 ± 9,07 b 480,16 ± 4,79 b 3 21 187,16 ± 8,89 b 472,05 ± 4,69 b AES Año N ߄ ± EE ߄ ± EE AES 1 1 6 228,16 ± 16,52 a 545,83 ± 8,72 a 2 7 163,28 ± 15,29 b 445,28 ± 8,08 b 3 8 126,62 ± 14,31 c 417,50 ± 7,55 c AES 2 1 6 266,33 ± 16,52 a 541,33 ± 8,72 a 2 7 176,42 ± 15,29 b 458,71 ± 8,08 b 3 7 169,85 ± 15,29 b 452,02 ± 8,08 b AES 3 1 5 246,80 ± 18,10 a 527,80 ± 9,56 a 2 6 258,66 ± 16,52 a 536,53 ± 8,72 a 3 6 265,02 ± 16,52 a 546,66 ± 8,72 a ab Different characters in the superscripts of each variable in the same column, within each source of variation indicate significant differences * P < 0.05 (Bonferroni 1936 ). AES: Agroecosystem. Discussion and conclusions The cows didn't have enough energy in the second year of AES 1 and 2, and in all three years of AES 3. This means that the cows would have to find other ways to use their energy, even if they could produce 11.7 L cow⁻³ day⁻³ (Butler et al. 2013 ; Balarezo et al. 2018 ). The increase in the PB content of the diet offered to animals is because SSPs increase the supply of forage to livestock, and the tree legumes in these agroecosystems provide more protein than grasses (Carvalho et al. 2017 ). In addition, cows in SSP have higher dry matter intake because they graze throughout the day, have less heat stress, show less competition and are better distributed, and spend much less time near the water trough. Consequently, cattle herds in silvopasture have higher productivity (Pent et al. 2020 , 2021 ; Poudel et al. 2022; Thomsen et al. 2023 ; Poudel et al. 2025 ). When there is too much CP and not enough energy, proteins are used as energy. This makes the liver use more N₂ and reaches its maximum capacity, which leads to more urea and NH₃ in the blood. This raises blood urea nitrogen (BUN) and causes the body to use more energy, making the energy balance even worse (Kananub et al. 2020 ). In addition, dairy cows can compensate for the energy deficit by mobilizing and utilizing body reserves. When the capacity of Edel rumen microorganisms to utilize NH3 is saturated, it reaches the liver via the bloodstream and is converted to urea by the liver, whereby excess NH3 leads to elevations in BUN, which harms reproductive behavior (Butler et al. 2013 ; Kananub et al. 2020 ). There were lower IPPS levels in AES 1 because the CCP level was higher (P < 0.05) than in AES 2 and AES 3 (Table 1 ). This is especially true for cows in AES 3 who are in BEN because their CCP is less than 3.0. This makes them less fertile because insulin and leptin levels drop, which in turn affects the ovary or hypothalamus function and slows down the production of gonadotropic hormones. This leads to low fertility and a longer time for the ovarian activity to start up again after giving birth in dairy cows (Butler et al. 2013 ; Balarezo et al. 2018 ). It has been shown that lower CCP affects fertility and that cows calving with CCP below three have higher postpartum anestrus and IPPS (Barletta et al. 2017 ). Similar results for these indicators were published by Balarezo et al. ( 2016 )d pez (2023) in AES, where a low body condition associated with increased IPPS was diagnosed. Low CCP accentuates CC loss; early lactation is among the main factors associated with increased S/G in dairy cows, due to reduced gestation rate in the first AI (Gobikrushanth et al. 2019 ). When there is too much loss of CC between giving birth and the first insemination, the IPG goes up (Carvalho et al. 2014 ) and the gestation rate goes down (Butler et al. 2013 ). Cows with low CC have lower postpartum ovulation rates due to Luteinizing Hormone (LH) deficiency that partially generates atypical waves of this hormone (Robson et al. 2008 ). Consequently, there is little development of the corpus luteum (CL) and little progesterone secretion (P4). This phenomenon explains the fertility disorders in cows with poor CC (Robson et al. 2007 ). IPPS was lower in years two and three (Table 1 ), motivated because in these years AES 1 and AES 2 were more established and therefore animals were more efficiently taking advantage of their benefits. BEN lowers the growth of dominant follicles and the production of estradiol because it lowers the amount of insulin and IGF-1 in the blood and the frequency of the LH pulse (Souissi and Bouraoui 2020 ). Thus, negative feedback, mediated by estradiol, is directly related to BE, and this physiological scenario delays first ovulation in cows with higher CC loss and lower nadir body condition (Barletta et al. 2017 ). To sum up, Table 1 shows that the CCP didn't change over the study years, and the S/G didn't change over the AES either. However, it was higher in the first year (P < 0.05), which means that this indicator is poor since only 34.36% of pregnancies happened at the first artificial insemination service. The adequate value of the S/G should be ≤ 1.70 for an adequate fertility level, where more than 60% of the cows are gestated with an insemination (Brito et al. 2010 ). To sum up, Table 1 shows that the CCP didn't change over the study years, and the S/G didn't change over the AES either. However, it was higher in the first year (P < 0.05), which means that this indicator is poor since only 34.36% of pregnancies happened at the first artificial insemination service. The adequate value of the S/G should be ≤ 1.70 for an adequate fertility level, where more than 60% of the cows are gestated with an insemination. Excesses of CP and energy deficiency lead to an increase in BUN, which lowers the pH of the uterus and consequently affects semen and embryo survival. This results in low percentages of gestation at first service, increased need for repeat services, and a decline in reproductive indicators. The excess of CP in the diet of dairy cows decreases their fertility and worsens the reproductive efficiency of the herd, especially when the energy does not satisfy their needs (Kananub et al. 2020 ). Dietary energy deficiencies are the main limiting factors for SSPs (Balarezo et al. 2018 ). In production conditions similar to those of this study, these authors showed that higher BUN levels were linked to S/G, IPC, IPP, and the return of ovarian activity. However, increasing the PB content of the diet or its rumen degradability, especially when the energy is not sufficient to meet the animals' needs, leads to decreased fertility in dairy cows and, therefore, to a decrease in the reproductive efficiency of the herd (Kananub et al. 2020 ). The PPI was different (P 0.05) between AES in the same year or between AES in the same year. This is likely because there were only nine animals in each group, which is a small sample size. However, in AES 1 in Year 3, the birth rate is very close to the target for optimum fertility potential, which is 90% (Brito et al. 2010 ). As shown in Table 1 , the animals in AES 3 had lower CCP than those in AES 2 and higher CPI than those in AES 2. This was true even though the animals in AES 2 ate the same amount of energy and protein and no year could meet their energy needs. This may be because the trees in AES 3 improve the animals' thermal comfort and welfare, protect them from solar radiation, and lower the effects of heat stress by making them work less to keep their systems in balance (Castaño et al. 2014 ). These results corroborate the beneficial effect of SSP on the CC of the cows, which had better reproductive performance (Vargas-Hernández 2013 ). It has been documented that under the shade of trees, the ambient temperature can be reduced between 2 and 9°C during the hottest hours of the day (López et al. 2015 ). El bienestar animal es el factor determinante en la viabilidad técnica y económica de los sistemas de producción de leche (Arciniegas-Torres y Flórez-Delgado 2018; Thomsen et al. 2023 ; Poudel et al. 2025 ). Alder and Acacia favored the nutrient balance in AES 1 and 2, with AES 2 showing an energy deficit. In AES 1, the CCP was higher, and the IPPS was reduced; the interaction of AES with the year of study benefited the IPC and IPP, which were better in AES 1 (Alder) in the third year. Declarations Acknowledgments The authors of this work are grateful to the administration of the San Vicente Farm, the setting for this research, and to the authorities, teachers, and students of the Universidad Politécnica Estatal del Carchi (UPEC) for their disinterested contribution to its realization. Authors’ contributions HRBR: research conception and design, data analysis and interpretation, and article writing. LRBU, EMIR, RMCV, GAJS, data analysis and interpretation, article writing JRGD: Research conception and design, statistical analysis, final review, and article approval. Main financial source of the study This research was financed with internal resources from the Universidad Politécnica Estatal del Carchi, through the cost center of the Research Department, within the framework of the project entitled “Management plan for the sustainable development of the San Francisco Experimental Center - UPEC”. The authors and the University have no conflict of interest with the postulated contribution, since it is paid to the main institution UPEC. Data availability Primary research data are available. Conflict of interest The authors have no conflict of interest. Institution responsible for the results Faculty of Agricultural Industries and Environmental Sciences, Universidad Politécnica del Carchi, Ecuador. References Amorim HCS, Ashworth AJ, O’Brien PL, Thomas AL, Runkle BRK, Philipp D (2023) Temperate silvopastures provide greater ecosystem services than conventional pasture systems. 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Ubicación del AES 1. https://earth.google.com/web/@0,-1.16600013,0a ,22251752.77375655d,35y,0h,0t,0r/data=CgRCAggBOgMKATBCAggBSg0I INAMHI (2022) Instituto Nacional de Meteorología e Hidrografía. Datos meteorológicos de la estación meteorológica de Chalpatán, Carchi, Ecuador. Internet Disponible en: http://www.inamhi.gob.ec . [Accedido: 19 marzo 2023]. Kananub S, Pechkerd P, VanLeeuwen J, Stryhn H, Arunvipas P (2020). Evaluation of influence of milk urea nitrogen on reproductive performance in smallholder dairy farms. Aust. Vet. J 98:375–379. https://doi.org/10.1111/avj.12946 . López O, Lamela L, Montejo IL. y Sánchez Tania (2015) Influencia de la suplementación con concentrado en la producción de leche de vacas Holstein x Cebú en silvopastoreo. Pastos y Forrajes 38 (1):46–54. http://scielo.sld.cu/pdf/pyf/v38n1/pyf05115.pdf López O (2023) Influencia del balance de energía en el desempeño productivo y reproductivo de vacas Mambí de Cuba en un sistema silvopastoril. Tesis presentada en opción al grado científico de Doctor en Ciencias Veterinarias. Universidad Ahraria de la Habana. MES. Mayabeque, Cuba. 53 p. Pent GJ, Greiner SP, Munsell JF, Tracy BF, Fike JH (2020) Lamb performance in hardwood silvopastures, I: animal gains and forage measures in summer. Transl Anim Sci 4(1):385–399. https://doi.org/10.1093/tas/txz154 Pent GJ, Fike JH, Kim I (2021) Ewe lamb vaginal temperatures in hardwood silvopastures. Agrofor Syst 95(1):21–32. https://doi.org/10.1007/s10457-0180221-y Poudel S, Pent G, Fike J (2024) Silvopastures: benefits, past efforts, challenges, and future prospects in the United States. Agronomy 14(7):1369. https://doi.org/10.3390/agron omy14 071369 Poudel S, Ely K, Fike J (2025). The potential of silvopasture in the mid-atlantic USA: insights from land managers on motivations, challenges, and production features. Agrofor Syst 99 (3), 52. https://doi.org/10.1007/s10457-025-01145-4 Robson C, Aller J, Callejas S, Cabodevila J, Alberio R (2007) Factores que afectan el anestro posparto en bovinos. Taurus Olivos Pcia. Bs. As 9 (33): 8–25. https://www.produccion-animal.com.ar/informacion_tecnica/cria/96-anestro.pdf Robson C, Aller, JF, Callejas, S Alberio RH (2008) Dinámica folicular y comportamiento del amamantamiento en razas Angus y criolla Argentina. Arch. Zootec 57 (220): 477–488. https://www.redalyc.org/pdf/495/49515034009.pdf Roche A, Larduet R, Torres V, Ajete A (1999) CALRAC. Programa de computación para el cálculo de raciones en rumiantes. Revista Cubana de Ciencia Agricola 33 (1):13. Rodenburg J (2004) Body Condition Scoring of Dairy Cattle. OMAFRA Factsheet. [online] Order (92–122): 414–420. Disponible en: http://www.omafra.gov.on.ca/english/livestock/dairy/facts/00-109.htm [Accedido: 04/09/20]. Souissi W, Bouraoui R (2020) Relationship between body condition score, milk yield, reproduction, and biochemical parameters in dairy cows. In: Biology, physiological basis, nutritional requirements, and modelization . M'Hamdi, Naceur (Ed.). National Agronomic Institute. ISBN: 978-1-78984-547-1. https://doi.org/10.5772/intechopen.85343 StatPoint Technologies (2010) Statgraphics Centurion. (ser. Centurion), version 16.1 (XV), [Windows], Disponible en: http://statgraphics-centurion.software.informer.com/download/ [Accedido: 15/04/2012]. Thomsen SJ, Poudel S, Fike JH, Pent GJ (2023) Heifer performance and body temperatures in an open pasture versus silvopasture in the mid-Atlantic USA. Agrofor Syst 98:47–59. https://doi.org/10.1007/s10457-023-00889-1 Tzec-Gamboa Magnolia del C, Álvarez-Rivera OO, Ramírez-Avilés L, Solorio-Sánchez FJ (2023) Decomposition and nitrogen release rates of foliar litter from single and mixed agroforestry Species under field conditions. Agriculture 13 (1): 222–238. https://doi.org/10.3390/agriculture13010222 Vargas-Hernández S (2013) Producción de leche bovina tropical sostenible. Diseño, manejo y evaluación de agroecosistemas. Un enfoque integrado. Editorial Académica Española, AV Akademikerv Erlag GmbH & Co. KG Heinrich-Böcking-Str. 6–8 D – 66121 Saarbrücken. ISBN 978-3-639-55125-9. 158p. Viñoles C, Fedrigo JK, Gonzalez VB, García L, Báez F (2022) Avances en el conocimiento sobre Sistemas Silvopastoriles en Uruguay. Archivos Latinoamericanos de Producción Animal 30 (Supl. 1), 43–53. https://doi.org/10.53588/alpa.300505 Wilkens P, Munsell JF, Fike JH, Pent GJ, Frey GE, Addlestone BJ, Downing AK (2022) Thinning forests or planting fields? Producer preferences for establishing silvopasture. Agrofor Syst 96(3):553–564. https://doi.org/10.1007/s10457-21-00665-z Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-6856634","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":470317054,"identity":"d979a171-8b10-475a-9a00-dd54173cb5a1","order_by":0,"name":"Hernán Rigoberto Benavides Rosales","email":"data:image/png;base64,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","orcid":"","institution":"Universidad Politécnica Estatal del Carchi","correspondingAuthor":true,"prefix":"","firstName":"Hernán","middleName":"Rigoberto Benavides","lastName":"Rosales","suffix":""},{"id":470317056,"identity":"e9eeeaf3-06f0-4956-accc-005079ec8c4c","order_by":1,"name":"Luis Rodrigo Balarezo Urresta","email":"","orcid":"","institution":"Universidad Politécnica Estatal del Carchi","correspondingAuthor":false,"prefix":"","firstName":"Luis","middleName":"Rodrigo Balarezo","lastName":"Urresta","suffix":""},{"id":470317059,"identity":"cb7e8d15-714a-49af-b5de-35959bc497c6","order_by":2,"name":"Edison Marcelo Ibarra Rosero","email":"","orcid":"","institution":"Universidad Politécnica Estatal del Carchi","correspondingAuthor":false,"prefix":"","firstName":"Edison","middleName":"Marcelo Ibarra","lastName":"Rosero","suffix":""},{"id":470317061,"identity":"a533bf9e-f66f-48e5-9fe8-41c9d53205bd","order_by":3,"name":"Rolando Martín Campos Vallejo","email":"","orcid":"","institution":"Universidad Politécnica Estatal del Carchi","correspondingAuthor":false,"prefix":"","firstName":"Rolando","middleName":"Martín Campos","lastName":"Vallejo","suffix":""},{"id":470317062,"identity":"2989a33b-c1cc-44fb-81db-1a53cc3082db","order_by":4,"name":"Guillermo Alexander Jácome Sarchi","email":"","orcid":"","institution":"Universidad Politécnica Estatal del Carchi","correspondingAuthor":false,"prefix":"","firstName":"Guillermo","middleName":"Alexander Jácome","lastName":"Sarchi","suffix":""},{"id":470317063,"identity":"4d8e218a-be9b-4ef0-be42-e7b5fec6ed77","order_by":5,"name":"Juan Ramón García Díaz","email":"","orcid":"","institution":"Universidad Central “Marta Abreu” de Las Villas","correspondingAuthor":false,"prefix":"","firstName":"Juan","middleName":"Ramón García","lastName":"Díaz","suffix":""}],"badges":[],"createdAt":"2025-06-09 17:38:25","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6856634/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6856634/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":84698468,"identity":"1cc5211f-119a-4792-8d9d-11adb11a42fb","added_by":"auto","created_at":"2025-06-16 11:04:10","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1432795,"visible":true,"origin":"","legend":"\u003cp\u003eLocation, establishment, and characteristics of AES 1, with Alder trees, which were planted following contour lines and protected with double electric fences (Google Earth, Anexo 1. Ubicación del AES 1, 2019)\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-6856634/v1/23b551d5425b4eb06a70349d.png"},{"id":84698057,"identity":"dd99885f-f8d2-45cb-b5c7-0442d22efeed","added_by":"auto","created_at":"2025-06-16 10:56:10","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":1174724,"visible":true,"origin":"","legend":"\u003cp\u003eFigure depicts the location, establishment, and characteristics of AES 2, which features Acacia trees planted in accordance with contour lines and safeguarded by double electric fences. Imagen capturada desde Google (Google Earth, Anexo 1. Ubicación del AES 1, 2019)\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-6856634/v1/bb9ff896f29b5888531edaa9.png"},{"id":84698055,"identity":"622e8f36-7405-4040-8e1d-aeb5c5b19183","added_by":"auto","created_at":"2025-06-16 10:56:10","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":1383032,"visible":true,"origin":"","legend":"\u003cp\u003eUbicación y características de AES 3 (Control) Imagen capturada desde Google (Google Earth, Anexo 1. Ubicación del AES 1, 2019)\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-6856634/v1/92d09378dde8bfc5ec37fe0a.png"},{"id":88470179,"identity":"1d083d60-f814-40fb-921d-333e05c095a3","added_by":"auto","created_at":"2025-08-06 18:46:34","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":6607156,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6856634/v1/9f8557b9-9257-416c-9f00-5fb154861ee2.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Nutritional status and reproductive performance of cattle agroecosystems in silvopastoralism in the Andean region of Ecuador","fulltext":[{"header":"Introduction","content":"\u003cp\u003eFeeding of specialized cattle herds in the Andean region of Ecuador is based on extensive grazing, with a predominance of monoculture of tropical grasses and the absence of trees (Balarezo et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), like what happens in tropical areas of Latin America (Durand-Ch\u0026aacute;vez et al. \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Under these conditions, soils are degraded, there is a low supply of shade, the quantity and quality of edible biomass are affected, and the bio-economic behavior of the animals is affected (Donaghy et al. \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn the agro-ecosystems (AES) of the Carchi province, dairy cows don't get enough of the nutrients they need. As a result, they have high levels of blood urea nitrogen (BUN) and beta hydroxybutyrate (B-OH) in their serum, as well as low levels of phosphorus, potassium, and phosphorous (Balarezo et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). All of these changes were linked to worsening reproductive indicators.\u003c/p\u003e \u003cp\u003eLa implementaci\u0026oacute;n de Sistemas Silvopastorales (SSP) es una alternativa para resolver problemas ecol\u0026oacute;gicos causados por la ganader\u0026iacute;a extensiva (Amorim et al. \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2023\u003c/span\u003e) y beneficiar la salud y producci\u0026oacute;n animal (Buitrago et al. 2018; Wilkens et al. \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Thomsen et al. \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Poudel et al. \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). In addition, these ESAs generate positive economic impacts through other marketable products or income diversification, reduce erosion, and benefit the environment (Amorim et al. \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2023\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eSSPs generate positive interactions among their components, with better reproductive performance for the animals and less negative environmental impact (Benavides et al. \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). In addition, they reduce the use of external inputs in agricultural SSAs (Tzec-Gamboa et al. \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2023\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eAdding trees to the mix of soil, plants, and animals improves the nutritional value of the edible phytomass and the amount of DM and nutrients that are available to each animal every day. This lowers the nutritional deficit and, as a result, makes the cows healthier during labor and birth, and it also affects how they reproduce (Vargas-Hern\u0026aacute;ndez \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2013\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn addition, SSPs contribute to animal comfort by reducing heat stress, resulting in improved production cycles and improved diet quality (Vi\u0026ntilde;oles et al. \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Cattle placed under shade feel more comfortable and have less caloric stress; therefore, they will consume feed for a longer time, which increases their productivity and improves reproductive parameters (Arciniegas-Torres and Fl\u0026oacute;rez-Delgado \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Thomsen et al. \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Poudel et al. \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2025\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eSilvopastoralism has many benefits, but most cattle producers don't use it because they don't know enough about it, don't have the resources to set up SSPs, and their animals' reactions vary from place to place because of differences in tree and pasture species, as well as soil and weather conditions (Poudel et al. 2021).\u003c/p\u003e \u003cp\u003eThe impact of the introduction of SSP on the nutrient balance and reproductive behavior of dairy herds using low external inputs in the Andean region of Ecuador is unknown.\u003c/p\u003e \u003cp\u003eThe point of this study was to look into what changes happen when you add SSP with Alnus acuminata H.B.K. (Alder) y Acacia melanoxylon R.Br. (Acacia), along with the herbaceous cover, to the nutritional status and reproductive performance of ganaderos in silvopastoralism in Ecuador's Andean region.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eResearch scenario and its edaphoclimatic conditions\u003c/h2\u003e \u003cp\u003eThe research was carried out during the years 2020, 2021, and 2022 in dairy herds of the San Vicente farm, parish \u0026ldquo;El Carmelo,\u0026rdquo; Tulc\u0026aacute;n canton, Carchi province, Ecuador. The experimental area is in the hydrographic area 230, from latitude 0\u0026ordm;39'33\"N, longitude 77\u0026ordm;36'20\"W to latitude 0\u0026ordm;38'55\"N, longitude 77\u0026ordm;36'25\"W, with an altitude of 2916 to 3006 m.a.s.l. (INAMHI \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe research site is 54.4 ha. Its soil is in the Andisol order, whose MO, pH, water retention, and effective depth fluctuate between 10 and 25%, 5.5 and 6.5%, 20 and 100%, and 20 and 70 cm, respectively. The relief undulates with a slope percentage that fluctuates between 10 and 40%, and N2 varies from medium to high values. The main limiting factor of the soils of the Andean region of Ecuador is acidity (Benavides et al. \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2019\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eLa precipitaci\u0026oacute;n en los a\u0026ntilde;os del experimento vari\u0026oacute; de 892.50 a 1,317.50 mm. The average mean, maximum, and minimum temperatures during the study period were 12.12, 16.49, and 8.06\u0026deg;C, respectively (INAMHI \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eAgro-ecosystem characteristics (AES)\u003c/h3\u003e\n\u003cp\u003eThree AES were used in a completely randomized experimental design. The predominant grasses in the three AES were Kikuyu (Pennisetum clandestinum L.), Ray grass (Lolium perenne L.), Holco (Holcus lanatus L.), and White clover (Trifolium repens L.). AES 1 (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) was composed of grasses and A. acuminata trees, AES 2 (Fig.\u0026nbsp;2) of grasses and A. melanoxylon trees, and AES 3 of grasses only; the same was considered a control.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eTrees in AES 1 and AES 2 were established in December 2019, at a planting density of 1000 trees ha⁻\u0026sup1;, in double rows, two meters apart, following contour lines (Figs.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e and 2). We established double electric fences to protect the young trees from cow damage, which also served to divide the quarters. The practices used to design and establish the AES are consistent with those used in other countries (Poudel et al. \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2025\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eTime-restricted grazing was used for 18 hours per day. No protein energy concentrate was administered, but mineral salts were supplemented orally ad libitum. Mechanized milking of the cows was used twice a day, 5:00\u0026ndash;7:00 am and 3:00\u0026ndash;5:00 pm. The calf underwent artificial rearing from the third day of its birth.\u003c/p\u003e\n\u003ch3\u003eAnimals involved\u003c/h3\u003e\n\u003cp\u003eBetween 29 and 34 cows were used, and 9 to 12 cows were randomly assigned to each AES. The animals met the following criteria: Holstein cows between three and four years of age, with CC at calving (CCP) between 3.0 and 4.0 points on the five-point scale, were in third and fourth lactation with an average milk production of 10\u0026thinsp;\u0026plusmn;\u0026thinsp;2 L cow⁻\u0026sup1; day⁻\u0026sup1;, clinically healthy, not receiving medical treatment, and had an average milk production of 10\u0026thinsp;\u0026plusmn;\u0026thinsp;2 L cow⁻\u0026sup1; day⁻\u0026sup1;.\u003c/p\u003e\n\u003ch3\u003eMetodologies of work\u003c/h3\u003e\n\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eHealth status\u003c/h2\u003e \u003cp\u003eGeneral health status was determined at the beginning of the experiment and followed throughout the study, using the functional invariants of the clinical method (Cuesta et al. \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2007\u003c/span\u003e). The animals were dewormed and vaccinated according to the area's schedule.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eNutritional balance\u003c/h2\u003e \u003cp\u003e The nutritional balance was calculated according to the feed offered (pasture mix, mineral salt, and the foliage of the trees in the third year), the requirements of the cows, and the contribution of each year. In addition, the average annual PV, PV increase, potential and actual milk fat percentage, locomotion expense, feed consumed, and number of lactations were considered. For this calculation, he used the software developed by Roche et al. (\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e1999\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eIndicators of reproductive performance and body condition\u003c/h3\u003e\n\u003cp\u003eWe used the methods explained by Brito et al. (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2010\u003c/span\u003e) to find out the birth index (NI), the percentage of gestations at first service, the services per gestation (S/G), the calving-first service interval (IPPS), the calving-conception interval (CPI), and the calving-calving interval (CPI). Estrus detection was performed between 5:00\u0026ndash;9:00 am and 3:00\u0026ndash;7:00 pm by a trained man, using paint at the base of the cows' tails as an auxiliary method.\u003c/p\u003e \u003cp\u003eFor artificial insemination, the semen was deposited in the uterus by an experienced technician, with a technical efficiency between 60 and 65% in the past four years. We used semen from Holstein bulls with proven fertility, which we contained in 0.25 c.c. straws at a concentration of 32\u0026nbsp;million per dose.\u003c/p\u003e \u003cp\u003eBody condition (CC) was estimated by physical examination of the animals that included inspection and palpation, classifying it on a scale of 1\u0026ndash;5 points and divisions of 0.25 between them according to the methodology proposed by Rodenburg (\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2004\u003c/span\u003e). Due to the limited number of animals in the AES under study, we only determined CC at calving (CCP).\u003c/p\u003e\n\u003ch3\u003eStatistical processing\u003c/h3\u003e\n\u003cp\u003eMultifactorial analysis of variance (multifactorial ANOVA) was used to find out how AES and year affected reproductive indicators (IPPS, IPC, IPP, and S/G) and CCP. Means were compared using the Bonferroni test (Bonferroni \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e1936\u003c/span\u003e). We compared the birth rate within each AES year and between years within the AES using a multiple comparison of proportions. We used the statistical package Statgraphics Centurion version XV for statistical processing (Statistical Graphic Corp., USA 2006).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThe energy requirements of the cows in AES 1 were met at 107.37 and 103.34% in the first and third years, while in the second year 97.72% of the requirements were met and there was a deficit of 2.28 MJ; on the other hand, in AES 2 there was an energy deficit of 9.62, 15.48, and 1.25 MJ in years 1, 2, and 3, in that order. In AES 3, the energy demands were covered, except in the second year, where only 96.72% of the demands were covered, and the animals had a deficit of 2.93 MJ.\u003c/p\u003e \u003cp\u003eDuring the three years of the study, the crude protein requirements in all three AES exceeded their demands, ranging from 106.89–183.01%. Ca and P requirements were covered in all three AES and years between 100 and 152.35%.\u003c/p\u003e \u003cp\u003eFor the IPPS, there are significant differences (P \u0026lt; 0.05) between the AES, being lower in AES 1 (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Following the study, the voluntary waiting period (Brito et al. \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2010\u003c/span\u003e) should not be longer than 18 days before the first service calving interval (IPPS). In the herds that were looked at, this was 45 days, so the postpartum anestrus period (PPA) was 64, 34, 87.09, and 134.77 days for AES 1, AES 2, and AES 3.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\u003cdiv class=\"gridtable\"\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\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\u003eComparison of mean reproductive indicators (S/G and IPPS) and body condition at calving (BCC).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003c/colgroup\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSource\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eS/G\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eIPPS (Days)\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eCCP\u003c/p\u003e \u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e߄ ± EE\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e߄ ± EE\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e߄ ± EE\u003c/p\u003e \u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eAES\u003c/p\u003e \u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAES 1 (n = 21)\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2,31 ± 0,17\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e127,34 ± 5,86\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3,45 ± 0,07\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAES 2 (n = 20)\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2,48 ± 0,17\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e150,09 ± 5,98\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3,05 ± 0,07\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAES 3 (n = 17)\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2,35 ± 0,19\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e197,77 ± 6,50\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2,85 ± 0,08\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eYear\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1 (n = 17)\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2,91 ± 0,19\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e174,94 ± 6,50\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3,07 ± 0,08\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2 (n = 20)\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2,21 ± 0,17\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e147,99 ± 5,98\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3,08 ± 0,07\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3 (n = 21)\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2,00 ± 0,17\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e152,28 ± 5,86\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3,20 ± 0,07\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/table\u003e\u003c/div\u003e \u003cp\u003e\u003c/p\u003e \u003cp\u003e \u003csup\u003eabc\u003c/sup\u003e Different characters in the same column, within each source of variation, differ for P \u0026lt; 0.05, (Bonferroni \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e1936\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows that the CPI and PPI differed (P \u0026lt; 0.05) between AES and years, being lower in AES1 and years two and three. The AES's interaction with the year clearly influenced the CPI and PPI. AES 1 had the best results in year three, AES 2 in years two and three without differences between them, and in AES 3 the year had no influence. This is since the year's influence on the establishment of the AES was revealed.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\u003cdiv class=\"gridtable\"\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\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\u003eComparison of CPI and PPI averages in the three SSAs and study years\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003c/colgroup\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"3\" morerows=\"1\" nameend=\"c3\" namest=\"c1\" rowspan=\"2\"\u003e \u003cp\u003eSource\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eIPC (Days)\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eIPP (Days)\u003c/p\u003e \u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e\u003cb\u003e߄\u003c/b\u003e ± \u003cb\u003eEE\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e߄\u003c/b\u003e ± \u003cb\u003eEE\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"7\" nameend=\"c7\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAES\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eAES 1\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e21\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e172,69 ± 8.89\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e469,54 ± 4,69\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eAES 2\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e204,20 ± 9,07\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e484,01 ± 4,79\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eAES 3\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e256,82 ± 9,85\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e536,98 ± 5,20\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"7\" nameend=\"c7\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eYear\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e247,10 ± 9,85\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e538,32 ± 5,20\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e199,46 ± 9,07\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e480,16 ± 4,79\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e21\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e187,16 ± 8,89\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e472,05 ± 4,69\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAES\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eAño\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e\u003cb\u003eN\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e\u003cb\u003e߄\u003c/b\u003e ± \u003cb\u003eEE\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e߄\u003c/b\u003e ± \u003cb\u003eEE\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eAES 1\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e228,16 ± 16,52\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e545,83 ± 8,72\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e163,28 ± 15,29\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e445,28 ± 8,08\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e126,62 ± 14,31\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e417,50 ± 7,55\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eAES 2\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e266,33 ± 16,52\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e541,33 ± 8,72 \u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e176,42 ± 15,29\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e458,71 ± 8,08\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e169,85 ± 15,29\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e452,02 ± 8,08\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eAES 3\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e246,80 ± 18,10\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e527,80 ± 9,56\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e258,66 ± 16,52\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e536,53 ± 8,72\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e265,02 ± 16,52\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e546,66 ± 8,72\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/table\u003e\u003c/div\u003e \u003cp\u003e\u003c/p\u003e \u003cp\u003e \u003csup\u003eab\u003c/sup\u003e Different characters in the superscripts of each variable in the same column, within each source of variation indicate significant differences * P \u0026lt; 0.05 (Bonferroni \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e1936\u003c/span\u003e). AES: Agroecosystem.\u003c/p\u003e "},{"header":"Discussion and conclusions","content":"\u003cp\u003eThe cows didn't have enough energy in the second year of AES 1 and 2, and in all three years of AES 3. This means that the cows would have to find other ways to use their energy, even if they could produce 11.7 L cow⁻³ day⁻³ (Butler et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2013\u003c/span\u003e; Balarezo et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe increase in the PB content of the diet offered to animals is because SSPs increase the supply of forage to livestock, and the tree legumes in these agroecosystems provide more protein than grasses (Carvalho et al. \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). In addition, cows in SSP have higher dry matter intake because they graze throughout the day, have less heat stress, show less competition and are better distributed, and spend much less time near the water trough. Consequently, cattle herds in silvopasture have higher productivity (Pent et al. \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2020\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Poudel et al. 2022; Thomsen et al. \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Poudel et al. \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2025\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eWhen there is too much CP and not enough energy, proteins are used as energy. This makes the liver use more N₂ and reaches its maximum capacity, which leads to more urea and NH₃ in the blood. This raises blood urea nitrogen (BUN) and causes the body to use more energy, making the energy balance even worse (Kananub et al. \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIn addition, dairy cows can compensate for the energy deficit by mobilizing and utilizing body reserves. When the capacity of Edel rumen microorganisms to utilize NH3 is saturated, it reaches the liver via the bloodstream and is converted to urea by the liver, whereby excess NH3 leads to elevations in BUN, which harms reproductive behavior (Butler et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2013\u003c/span\u003e; Kananub et al. \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThere were lower IPPS levels in AES 1 because the CCP level was higher (P \u0026lt; 0.05) than in AES 2 and AES 3 (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). This is especially true for cows in AES 3 who are in BEN because their CCP is less than 3.0. This makes them less fertile because insulin and leptin levels drop, which in turn affects the ovary or hypothalamus function and slows down the production of gonadotropic hormones. This leads to low fertility and a longer time for the ovarian activity to start up again after giving birth in dairy cows (Butler et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2013\u003c/span\u003e; Balarezo et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIt has been shown that lower CCP affects fertility and that cows calving with CCP below three have higher postpartum anestrus and IPPS (Barletta et al. \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). Similar results for these indicators were published by Balarezo et al. (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2016\u003c/span\u003e)d pez (2023) in AES, where a low body condition associated with increased IPPS was diagnosed.\u003c/p\u003e\u003cp\u003eLow CCP accentuates CC loss; early lactation is among the main factors associated with increased S/G in dairy cows, due to reduced gestation rate in the first AI (Gobikrushanth et al. \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2019\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eWhen there is too much loss of CC between giving birth and the first insemination, the IPG goes up (Carvalho et al. \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2014\u003c/span\u003e) and the gestation rate goes down (Butler et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). Cows with low CC have lower postpartum ovulation rates due to Luteinizing Hormone (LH) deficiency that partially generates atypical waves of this hormone (Robson et al. \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2008\u003c/span\u003e). Consequently, there is little development of the corpus luteum (CL) and little progesterone secretion (P4). This phenomenon explains the fertility disorders in cows with poor CC (Robson et al. \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2007\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIPPS was lower in years two and three (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e), motivated because in these years AES 1 and AES 2 were more established and therefore animals were more efficiently taking advantage of their benefits.\u003c/p\u003e\u003cp\u003eBEN lowers the growth of dominant follicles and the production of estradiol because it lowers the amount of insulin and IGF-1 in the blood and the frequency of the LH pulse (Souissi and Bouraoui \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Thus, negative feedback, mediated by estradiol, is directly related to BE, and this physiological scenario delays first ovulation in cows with higher CC loss and lower nadir body condition (Barletta et al. \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2017\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eTo sum up, Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows that the CCP didn't change over the study years, and the S/G didn't change over the AES either. However, it was higher in the first year (P \u0026lt; 0.05), which means that this indicator is poor since only 34.36% of pregnancies happened at the first artificial insemination service. The adequate value of the S/G should be ≤ 1.70 for an adequate fertility level, where more than 60% of the cows are gestated with an insemination (Brito et al. \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2010\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eTo sum up, Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows that the CCP didn't change over the study years, and the S/G didn't change over the AES either. However, it was higher in the first year (P \u0026lt; 0.05), which means that this indicator is poor since only 34.36% of pregnancies happened at the first artificial insemination service. The adequate value of the S/G should be ≤ 1.70 for an adequate fertility level, where more than 60% of the cows are gestated with an insemination.\u003c/p\u003e\u003cp\u003eExcesses of CP and energy deficiency lead to an increase in BUN, which lowers the pH of the uterus and consequently affects semen and embryo survival. This results in low percentages of gestation at first service, increased need for repeat services, and a decline in reproductive indicators. The excess of CP in the diet of dairy cows decreases their fertility and worsens the reproductive efficiency of the herd, especially when the energy does not satisfy their needs (Kananub et al. \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eDietary energy deficiencies are the main limiting factors for SSPs (Balarezo et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). In production conditions similar to those of this study, these authors showed that higher BUN levels were linked to S/G, IPC, IPP, and the return of ovarian activity.\u003c/p\u003e\u003cp\u003eHowever, increasing the PB content of the diet or its rumen degradability, especially when the energy is not sufficient to meet the animals' needs, leads to decreased fertility in dairy cows and, therefore, to a decrease in the reproductive efficiency of the herd (Kananub et al. \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe PPI was different (P \u0026lt; 0.05) between AES and years (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), but the birth rate wasn't significantly different (P \u0026gt; 0.05) between AES in the same year or between AES in the same year. This is likely because there were only nine animals in each group, which is a small sample size. However, in AES 1 in Year 3, the birth rate is very close to the target for optimum fertility potential, which is 90% (Brito et al. \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2010\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eAs shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, the animals in AES 3 had lower CCP than those in AES 2 and higher CPI than those in AES 2. This was true even though the animals in AES 2 ate the same amount of energy and protein and no year could meet their energy needs. This may be because the trees in AES 3 improve the animals' thermal comfort and welfare, protect them from solar radiation, and lower the effects of heat stress by making them work less to keep their systems in balance (Castaño et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). These results corroborate the beneficial effect of SSP on the CC of the cows, which had better reproductive performance (Vargas-Hernández \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2013\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIt has been documented that under the shade of trees, the ambient temperature can be reduced between 2 and 9°C during the hottest hours of the day (López et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). El bienestar animal es el factor determinante en la viabilidad técnica y económica de los sistemas de producción de leche (Arciniegas-Torres y Flórez-Delgado 2018; Thomsen et al. \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Poudel et al. \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2025\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eAlder and Acacia favored the nutrient balance in AES 1 and 2, with AES 2 showing an energy deficit. In AES 1, the CCP was higher, and the IPPS was reduced; the interaction of AES with the year of study benefited the IPC and IPP, which were better in AES 1 (Alder) in the third year.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors of this work are grateful to the administration of the San Vicente Farm, the setting for this research, and to the authorities, teachers, and students of the Universidad Polit\u0026eacute;cnica Estatal del Carchi (UPEC) for their disinterested contribution to its realization.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHRBR: research conception and design, data analysis and interpretation, and article writing. LRBU, EMIR, RMCV, GAJS, data analysis and interpretation, article writing JRGD: Research conception and design, statistical analysis, final review, and article approval.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMain financial source of the study\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research was financed with internal resources from the Universidad Polit\u0026eacute;cnica Estatal del Carchi, through the cost center of the Research Department, within the framework of the project entitled \u0026ldquo;Management plan for the sustainable development of the San Francisco Experimental\u0026nbsp;Center\u0026nbsp;-\u0026nbsp;UPEC\u0026rdquo;. The authors and the University have no conflict of interest with the postulated contribution, since it is paid to the main institution\u0026nbsp;UPEC.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePrimary research data are available.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no conflict of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInstitution responsible for the results\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFaculty of Agricultural Industries and Environmental Sciences, Universidad Polit\u0026eacute;cnica del Carchi, Ecuador.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003e\u003cspan\u003eAmorim HCS, Ashworth AJ, O\u0026rsquo;Brien PL, Thomas AL, Runkle BRK, Philipp D (2023) Temperate silvopastures provide greater ecosystem services than conventional pasture systems. Sci Rep. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1038/s41598-023-45960-0\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eArciniegas-Torres SP, Fl\u0026oacute;rez-Delgado DF (2018) Estudio de los sistemas silvopastoriles como alternativa para el manejo sostenible de la ganader\u0026iacute;a. \u003cem\u003eCiencia y Agricultura\u003c/em\u003e 15 (2): 107\u0026ndash;116. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.19053/01228420.v15.n2.2018.8687\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eBalarezo LR, Garc\u0026iacute;a-D\u0026iacute;az JR, Hern\u0026aacute;ndez-Barreto M, Vargas-Hern\u0026aacute;ndez S (2018) Uterine Involution in Hosltein cows in the province of Carchi, Ecuador. \u003cem\u003eRev. 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Agrofor Syst 96(3):553\u0026ndash;564. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s10457-21-00665-z\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Silvopastoral systems, Agroecosystems, Body condition, reproductive indicators, Natality","lastPublishedDoi":"10.21203/rs.3.rs-6856634/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6856634/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe goal of this study was to find out how silvopastoral systems with Alnus acuminata H.B.K. (Alder) and Acacia melanoxylon R.Br. (Acacia) along with the herbaceous layer affect the nutritional status and reproductive performance of agroecosystems (AES) in Ecuador's Andean region with silvopastoral cattle. AES 1 and 2 contained alder and Acacia, respectively, and AES 3 contained grasses only. We determined the effect of AES and year on reproductive indicators and body condition at calving (BCC) using multifactorial ANOVA and interaction. There was an energy deficit in the second year in AES 1 and 3, and in all three years in AES 2. There was an excess of crude protein in all three AES in all three years. The first service parity interval (FPSI) was lower (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) in AES 1 and in years 2 and 3. The CCP was higher (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) in AES 1, and the services per gestation were higher (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) in the first year. Calving-conception (CCP) and calving-delivery (DDP) intervals were lower in AES1 and in years two and three. We conclude that Alder and Acacia favored nutrient balance in AES 1 and 2. In AES 1, CCP was higher, and IPPS was reduced; the interaction between AES and the year of study benefited CPI and IPP, which were better in AES 1, in the third year.\u003c/p\u003e","manuscriptTitle":"Nutritional status and reproductive performance of cattle agroecosystems in silvopastoralism in the Andean region of Ecuador","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-16 10:56:06","doi":"10.21203/rs.3.rs-6856634/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"478c5184-7195-4142-9ee1-566f19eb95a4","owner":[],"postedDate":"June 16th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-08-06T18:38:24+00:00","versionOfRecord":[],"versionCreatedAt":"2025-06-16 10:56:06","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6856634","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6856634","identity":"rs-6856634","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}