Impact of Nano Zinc Supplementation During Transition Period on Reproductive Performance, Serum Biochemical Indices and Metabolic Profile in Purebred Sahiwal Cows

Impact of Nano Zinc Supplementation During Transition Period on Reproductive Performance, Serum Biochemical Indices and Metabolic Profile in Purebred Sahiwal Cows | 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 Impact of Nano Zinc Supplementation During Transition Period on Reproductive Performance, Serum Biochemical Indices and Metabolic Profile in Purebred Sahiwal Cows Arvind Kumar Nandanwar, Dhirendra Bhonsle, Sonali Prusty, Vandana Bhagat This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8908298/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 4 You are reading this latest preprint version Abstract Micronutrients are essential for physiological functions and are especially crucial during the transition period. Zinc is one of such nutrients that plays a vital role in metabolism, immunity, endocrine regulation, reproductive physiology, and uterine health. Nano-zinc, due to its superior bioavailability, offers improved physiological benefits at lower supplementation levels. Twenty-four pregnant purebred Sahiwal cows were randomly assigned to four groups receiving a balanced diet without zinc (T0), zinc oxide at 40 ppm (T1), and nano zinc oxide at 20 ppm (T2) and 40 ppm (T3). Nano-zinc supplementation did not significantly affect reproductive performance but showed a non-significant reduction in the postpartum interval to estrus by 11–20%, and service period by 9.66–16.78%, and an increase in the conception rate compared to other treatments. The concentration of serum zinc varied significantly (P ≤ 0.05) among treatments, with the highest levels observed in the 40 ppm nano-zinc group during both the prepartum and postpartum periods, despite its superior bioavailability. Administration of nano zinc-supplemented groups caused a non-significant increase in cholesterol concentration as compared to other groups and contributed to better reproductive performance. Compared to the different treatments group feeding with nano zinc at 40 ppm showed significantly (P ≤ 0.01) lower concentrations of AST and ALT during prepartum and postpartum periods. Nano zinc Transition period Sahiwal Zinc status Liver function Conception rate Figures Figure 1 Introduction Adequate intake of zinc is crucial for meeting physiological needs, maintaining animal health, and supporting reproduction. Supplementing livestock diets with zinc is a common practice to prevent or address deficiencies and to mitigate biochemical and clinical disorders. Zinc acts as a signaling factor and plays a role in DNA synthesis (Hara et al. 2017 ). Zinc plays a pivotal role in various enzymes, which are essential for maintaining liver function. Zinc plays a crucial role in nutrient metabolism; therefore, it is necessary for growth and immune function. Lipid metabolism is compromised, and plasma cholesterol is increased in Zn deficiency (Shen et al. 2007 ). Zinc deficiency can lead to reduced feed intake, poor feed conversion, and impaired growth performance. In mature animals, inadequate zinc levels can lead to reproductive problems. Zinc plays a crucial role in oocyte maturation, fertilization, and the development of both the embryo and placenta (Garner et al. 2021 ; Wilson et al. 2017 ). Supplementation of Zn at an effective concentration modulates endocrine hormone levels during transition periods and improves reproductive efficiency in cows (Akil et al. 2025 ). The deficiency of zinc is common in ruminants, as the soil, feed, and fodder in many parts of India are reported to be zinc-deficient (Kumar et al. 2024 ). The absorption coefficient of Zn in ruminants varies in a wide range (NRC 2001 ), and performance is affected by the sources of Zn. Inorganic zinc has been shown to improve body weight, whereas a better effect on reproduction was observed from alternative sources of zinc (Fulton et al. 2023). Organic sources, such as Zn lysine, are recommended to have greater bioavailability than inorganic salts, like sulfate forms (Kinal and Slupczynska 2011 ). Nano Zn is reported to have a higher absorption rate due to its higher dissolution rate in the acidic pH of the stomach and surface activity (Cho et al. 2013 ). Nano Zn has been demonstrated to have added advantages over Zn salt, particularly in terms of feed intake, digestibility, blood Zn concentration, growth-stimulating and immunomodulatory effects, lactation performance, Zn concentrations in milk and plasma, and hematological profiles (Abdollahi et al. 2020 ; Cai et al. 2021 ; Swain et al. 2016 ). Zinc deficiency has been frequently observed during the transition phase (Maurya et al. 2014 ). Supplementation with nano-zinc at a reduced dose improved the quality and quantity of milk, while also helping to maintain the udder health of dairy cattle (Nandanwar et al. 2022 ). The effect of nano-Zn supplementation on the reproductive performance of indigenous Sahiwal cattle is not well studied. The present research work was conducted to investigate the effect of supplementing nano-Zn during the transition phase of purebred Sahiwal cows on reproductive performance, hormonal profile, and blood biochemical parameters. Materials and Methods Animals, Treatments and Management Twenty-four pregnant pure-bred Sahiwal cows in first to fifth parity (300–350 Kg body weight) from Bull Mother Experimental Farm (BMEF) of the College of Veterinary Science and Animal Husbandry, Durg, Chhattisgarh, were grouped randomly into four treatment groups according to parity. Cows were kept in naturally ventilated conventional barn housing with a concrete floor with paddy straw as bedding material for the duration of the trial. The pens were cleaned daily, and manure was removed periodically to keep them clean and dry. All cows in each pen had access to ad libitum fresh drinking water three times daily. The experimental cows were dewormed with fenbendazole @ 7.5 mg/kg. All experimental cows were given chaffed green fodder (Hybrid Napier, Sudan, Berseem, and local grasses), dry fodder (paddy straw), and a concentrate mixture (20% Crude protein, 0.93% Ether extract) in a shed and were left for 4 hours of grazing in the morning. The cows in each group were fed individually in the pen. During the experimental period, the control group (T0) was fed a basal diet without Zn supplementation, whereas the treatment groups were given a basal diet supplemented with Zn at 40 ppm from ZnO (T1), 20 ppm from nano Zn (T2), and 40 ppm from nano Zn (T3). Nano ZnO was characterised using a particle size analyzer and a scanning electron microscope (Fig. 1 ). The treatment diets were administered during the transition period, from 30 days prior to the expected date of calving and through 30 days after the actual date of calving. Studied Parameters Reproductive Traits Postpartum reproductive traits studied in this work included the postpartum interval to estrus (PPIE), service period, and conception rate during the first 200 days postpartum. After parturition, all experimental animals were observed regularly for signs of heat for the first 24 hours, both in the morning and evening. The interval from parturition to the onset of heat symptoms was recorded to determine the days from calving to the first heat. The dates of calving and conception were recorded for all animals to calculate the service interval. The conception rate was calculated using the formula: no. of pregnant animals X 100/no. of artificial inseminations. Biochemical Analysis For analysis of biochemical parameters, blood samples were collected from the jugular vein in clot-activator vials in the early morning before feeding and watering. The sampling was done on -21, -14, -7, -5, -3, -1 days prepartum and on the day of calving (day 0) as well as on + 1, +3, + 5, +7, + 14, +21 postpartum from individual animals. The clot-activator vials containing blood samples were kept in the rack at a 45° angle at room temperature for 60–120 minutes, followed by centrifugation at 1000 rpm for 10 minutes, and clear supernatant serum was decanted into pre-labelled Eppendorf tubes and deep frozen (-20°C) till further analysis. Serum Zn concentration was determined by an Atomic Absorption Spectrophotometer after digestion in tri acid solution (Nitric acid: Sulphuric acid: Perchloric acid- 9:1:1). Serum samples were analyzed for cholesterol, AST, ALT in a semi-auto analyser using commercial diagnostic kits (Biolab Diagnostics Pvt. Ltd., Biosar, Maharashtra, India). Statistical Analysis For interpretation of the results, the data were subjected to a completely randomized design (CRD) for one-way analysis of variance. The significance of differences among the groups was analyzed by Duncan's multiple range test (Snedecor and Cochran 1994 ). Results Reproductive Traits The postpartum interval to estrus (PPIE), average service period, and conception rate in Sahiwal cows under different dietary zinc supplementation levels are presented in Table 1 . Table 1 Effect of zinc supplementation on reproductive performance of Sahiwal cows Group Parameter T 0 T 1 T 2 T 3 Sig. level PPIE (Days) 128.83 ± 12.65 113.50 ± 7.31 102.66 ± 8.01 108.16 ± 9.32 NS Service period (Days) 182.66 ± 10.77 165.00 ± 8.50 152.00 ± 6.08 158.00 ± 6.33 NS Conception rate (%) 36 ± 11.48 44 ± 13.93 62.5 ± 12.59 55 ± 11.19 NS Postpartum Interval to Estrus The mean values of postpartum interval to estrus (PPIE) in T0, T1, T2, and T3 groups were 128.83, 113.50, 102.66, and 108.16 days, respectively. There was no significant difference between the treatment and control groups. However, compared to the control group, zinc supplementation reduced PPIE by 11.09%, 20.31%, and 16.04% in T1, T2, and T3, respectively. Service Period Interval The average interval of service period of Sahiwal cows was 182.66, 165.00, 152.00, and 158.00 days in T0, T1, T2, and T3 groups, respectively. Zinc supplementation in T1, T2, and T3 groups reduced the service period by 9.66%, 16.78% and 13.50%, respectively, compared to the control group. However, there was no significant difference between the treatment and control groups. Conception Rate The conception rate averaged 36%, 44%, 62.5% and 55% in T0, T1, T2, and T3 groups, respectively. There was a non-significant difference in the mean values of conception rate among the groups of Sahiwal cows. However, the nano zinc-supplemented groups (T2 and T3) showed a better conception rate compared to the control and inorganic zinc-supplemented groups. Serum Zn The effect of different zinc sources on the concentration of serum zinc in Sahiwal cows is shown in Table 2 . Serum zinc concentration was significantly affected by the treatments and the overall experimental period (P ≤ 0.05). The highest concentration was recorded in the 40 ppm nano zinc (T3) group of Sahiwal cows. The concentration of serum zinc gradually decreased towards calving and reached its lowest level on the third day postpartum across all treatment and control groups. Significantly higher (P ≤ 0.05 and P ≤ 0.01) serum zinc concentrations were observed at 1, 3, and 7 days prepartum, as well as at calving and on 5, 7, 14, and 21 days postpartum in the 40 ppm nano zinc group compared to other groups. Overall, the mean serum zinc concentration during the prepartum period was higher than during the postpartum period across all treatments. Table 2 Mean values (± SE) of serum zinc (ppm) in Sahiwal cows Periods of observations Serum zinc (ppm) in Sahiwal cows Sig. level Days relative to calving T 0 T 1 T 2 T 3 -21 1.55 ± 0.07 1.62 ± 0.05 1.66 ± 0.07 1.71 ± 0.09 NS -14 1.50 ± 0.04 1.55 ± 0.07 1.62 ± 0.05 1.73 ± 0.05 NS -7 1.34 c ±0.02 1.39 bc ±0.08 1.54 ab ±0.03 1.59 a ±0.07 * -5 1.25 ± 0.08 1.31 ± 0.02 1.38 ± 0.04 1.44 ± 0.08 NS -3 1.05 b ±0.05 1.18 ab ±0.04 1.26 a ±0.08 1.31 a ±0.02 * -1 1.02 b ±0.06 1.06 b ±0.04 1.17 a ±0.04 1.20 a ±0.03 * At Calving 0.96 b ±0.07 0.98 b ±0.03 1.13 a ±0.02 1.23 a ±0.02 ** + 1 0.90 b ±0.06 0.93 b ±0.05 1.04 ab ±0.05 1.15 a ±0.03 * + 3 0.80 ± 0.08 0.85 ± 0.09 0.93 ± 0.05 1.05 ± 0.04 NS + 5 0.89 b ±0.07 0.93 b ±0.05 1.04 ab ±0.02 1.14 a ±0.01 ** + 7 0.93 b ±0.06 0.96 b ±0.07 1.07 ab ±0.02 1.21 a ±0.03 ** + 14 1.08 b ±0.05 1.15 b ±0.05 1.32 a ±0.02 1.45 a ±0.04 ** + 21 1.14 b ±0.04 1.19 b ±0.03 1.54 a ±0.03 1.57 a ±0.07 ** Mean 1.10 b ±0.06 1.16 b ±0.06 1.28 ab ±0.06 1.36 a ±0.06 * Prepartum Mean 1.28 ± 0.09 1.35 ± 0.08 1.43 ± 0.08 1.49 ± 0.08 NS Postpartum Mean 0.95 b ±0.05 1.00 b ±0.05 1.15 ab ±0.09 1.26 a ±0.08 * a,b, c - Mean with different superscript in a row differ significantly *(P ≤ 0.05), **(P ≤ 0.01) Cholesterol Table 3 Mean values (± SE) of cholesterol (mg/dl) in Sahiwal cows Periods of observations Cholesterol (mg/dl) in Sahiwal cows Sig. level Days relative to calving T 0 T 1 T 2 T 3 -21 116.33 ± 2.47 118.62 ± 2.99 119.02 ± 2.76 121.18 ± 3.31 NS -14 109.00 ± 3.41 113.77 ± 2.35 116.09 ± 2.45 118.01 ± 2.83 NS -7 111.69 ± 2.05 109.16 ± 2.73 111.09 ± 2.44 110.00 ± 3.10 NS -5 103.61 b ±2.23 105.13 b ±2.17 107.38 ab ±2.13 113.06 a ±2.45 * -3 98.10 b ±2.43 100.73 ab ±2.35 104.08 ab ±1.75 107.00 a ±2.01 * -1 97.04 b ±1.85 99.03 ab ±2.08 103.81 a ±2.43 105.16 a ±2.11 * At Calving 96.90 b ±2.19 99.27 b ±1.74 102.69 ab ±2.09 108.00 a ±2.96 * + 1 99.24 ± 1.88 101.95 ± 2.17 106.03 ± 2.20 108.00 ± 2.96 NS + 3 105.05 c ±2.23 103.55 bc ±2.24 120.02 a ±3.24 112.66 ab ±2.58 ** + 5 105.10 b ±1.64 112.01 ab ±2.49 118.01 a ±3.05 110.17 ab ±3.25 * + 7 116.00 b ±2.53 109.30 b ±3.13 129.07 a ±3.18 128.06 a ±3.17 ** + 14 121.01 c ±3.29 124.08 bc ±3.19 133.03 ab ±2.87 136.03 a ±2.94 ** + 21 129.02 ± 3.02 135.70 ± 3.53 138.70 ± 2.98 141.86 ± 3.14 NS Mean 108.31 ± 2.78 110.17 ± 2.99 116.07 ± 3.27 116.86 ± 3.25 NS Prepartum Mean 105.96 ± 3.14 107.74 ± 3.10 110.24 ± 2.57 112.40 ± 2.55 NS Postpartum Mean 112.57 ± 4.63 114.43 ± 5.32 124.14 ± 4.82 122.79 ± 5.90 NS a,b,c - Mean with different superscript in a row differ significantly*(P ≤ 0.05) **(P ≤ 0.01) The mean serum cholesterol concentration during the transition period in Sahiwal cows under different dietary zinc supplementation is presented in Table 3 . The mean cholesterol concentration in Sahiwal cows for the T0, T1, T2, and T3 groups was 108.31, 110.17, 116.07, and 116.86 mg/dL, respectively. The prepartum means of cholesterol in the T0, T1, T2, and T3 groups were 105.96 ± 3.14, 107.74 ± 3.10, 110.24 ± 2.57, and 112.40 ± 2.55 mg/dL, respectively. The postpartum values were 112.57, 114.43, 124.14, and 122.79 mg/dL, respectively. The overall cholesterol concentration during the prepartum period was lower than that during the postpartum period in all groups. The treatment-related differences were more pronounced during early and mid-lactation (3, 5, 7 and 14 postpartum). During these periods, cows in T2 and T3 exhibited significantly higher cholesterol concentrations compared to T0 and T1. Decline in serum cholesterol concentration approaching calving, followed by a gradual and significant increase during the postpartum period, with treatment-related differences being more pronounced during early and mid-lactation. Aspartate Aminotransferase (AST) The AST enzyme in the liver plays a role in the metabolism of amino acids. The AST test may help diagnose and monitor liver problems. These enzymes are released when the liver is damaged and the concentration of serum AST is increased. The mean serum concentration of AST during the transition period in Sahiwal cows under different dietary zinc supplementation has been shown in Table 4 . The mean concentration of AST of Sahiwal cows in T0, T1, T2, and T3 groups was 90.99 ± 1.89, 84.61 ± 1.34, 81.46 ± 1.14, and 79.19 ± 1.38 U/L, respectively. The prepartum mean of AST of Sahiwal cows in T0, T1, T2 and T3 groups were 85.15 ± 1.91, 80.88 ± 1.85, 78.53 ± 1.85 and 75.39 ± 1.87 U/L, respectively and the postpartum values were 96.64 ± 1.29, 88.16 ± 0.81, 84.28 ± 0.28 and 83.00 ± 0.77 U/L, respectively. Significant differences were observed in overall mean as well as postpartum and prepartum mean values. Significant differences were observed in the overall mean, as well as in prepartum and postpartum mean values among the groups. The prepartum and postpartum mean concentrations of AST were found to be significantly (P ≤ 0.05 and P ≤ 0.01, respectively) lower in the T3 and T2 groups. The mean concentration of serum AST was significantly (P ≤ 0.01) lower in the T3 group, followed by the T2 and T1 groups, compared to the control group. Increased AST activity from prepartum to postpartum period, with consistently higher enzyme activity in T0, suggests greater metabolic and hepatic load around calving and early lactation without Zn supplementation. Table 4 Mean values (± SE) of AST conc. (U/L) in Sahiwal cows Periods of observations AST (U/L) in Sahiwal cows Sig. level Days relative to calving T 0 T 1 T 2 T 3 -21 76.24 a ±1.93 72.80 ab ±1.35 70.05 b ±2.12 67.05 b ±2.40 * -14 83.74 a ±2.17 78.38 ab ±1.82 76.72 b ±2.00 73.31 b ±1.18 ** -7 87.57 a ±2.06 83.00 ab ±2.85 80.28 ab ±2.81 77.03 b ±1.97 * -5 87.17 ± 2.47 82.82 ± 3.07 81.05 ± 1.43 76.82 ± 2.81 NS -3 87.42 ± 1.87 83.25 ± 2.09 81.38 ± 2.06 79.09 ± 2.27 NS -1 88.78 a ±2.14 85.06 ab ±2.44 81.71 b ±1.99 79.04 b ±1.90 * At Calving 92.17 a ±3.05 85.71 ab ±3.01 82.10 b ±3.06 79.24 b ±2.21 * + 1 93.14 a ±2.41 85.13 b ±2.70 83.04 b ±2.45 80.40 b ±2.80 * + 3 95.18 a ±2.38 87.01 b ±2.50 84.25 b ±2.11 82.06 b ±1.81 ** + 5 95.18 a ±1.93 87.86 b ±1.99 84.74 b ±1.97 83.05 b ±2.20 ** + 7 95.18 a ±1.93 88.91 ab ±2.14 84.81 b ±2.44 85.37 b ±2.46 * + 14 101.12 a ±2.90 91.03 b ±2.96 84.81 b ±2.44 85.01 b ±3.05 ** + 21 100.08 a ±2.60 89.02 b ±2.20 84.06 b ±2.87 82.12 b ±3.17 ** Mean 90.99 a ±1.89 84.61 b ±1.34 81.46 bc ±1.14 79.19 c ±1.38 ** Prepartum Mean 85.15 a ±1.91 80.88 ab ±1.85 78.53 b ±1.85 75.39 b ±1.87 * Postpartum Mean 96.64 a ±1.29 88.16 b ±0.81 84.28 c ±0.28 83.00 c ±0.77 ** a,b,c - Mean with different superscript in a row differ significantly*(P ≤ 0.05) **(P ≤ 0.01) Alanine Aminotransferase (ALT) The function of ALT is to convert alanine into pyruvate for cellular energy production. High levels of these enzymes can be a sign that the liver is injured. The mean serum concentration of ALT during the transition period in Sahiwal cows under different dietary zinc supplementation has been shown in Table 5 . The mean concentration of ALT of Sahiwal cows in T0, T1, T2, and T3 groups was 37.03 ± 1.65, 34.06 ± 1.54, 28.72 ± 0.86, and 28.61 ± 0.79 U/L, respectively. The serum enzyme ALT level increased gradually up to 3 days postpartum, then remained stable from 21 days into the prepartum period, followed by a decline thereafter in all treatment groups. The overall ALT concentration during the prepartum period was lower than that during the postpartum period in all groups. The prepartum and postpartum mean concentration of ALT was found significantly (P ≤ 0.01) lower in the T2 and T3 groups. There was a significant variation in the mean serum ALT concentration of Sahiwal cows across the treatments (P < 0.01), with the T3 and T2 groups having significantly lower concentrations (P ≤ 0.01), followed by the T1 group, and then the control group. Table 5 Mean values (± SE) of ALT conc. (U/L) in Sahiwal cows Periods of observations ALT (U/L) in Sahiwal cows Sig. level Days relative to calving T 0 T 1 T 2 T 3 -21 28.10 ± 2.04 25.61 ± 1.76 23.82 ± 1.23 23.61 ± 0.81 NS -14 29.40 a ±1.16 26.82 ab ±2.06 22.92 b ±1.39 23.90 b ±0.76 * -7 30.20 ± 2.18 27.78 ± 1.86 25.88 ± 1.94 26.96 ± 1.70 NS -5 31.80 ± 2.34 28.91 ± 1.29 27.05 ± 2.14 26.53 ± 1.89 NS -3 34.07 ± 2.82 30.05 ± 2.17 28.42 ± 1.92 27.82 ± 1.92 NS -1 36.09 ± 2.77 33.74 ± 2.73 29.05 ± 1.85 28.61 ± 1.98 NS At Calving 37.85 ± 2.33 35.90 ± 3.29 30.12 ± 2.41 30.01 ± 1.74 NS + 1 39.35 ± 2.96 37.18 ± 1.64 31.39 ± 2.53 31.00 ± 2.17 NS + 3 46.08 a ±3.41 41.68 ab ±3.32 33.18 b ±2.73 32.94 b ±2.05 ** + 5 44.38 a ±3.11 40.36 ab ±2.97 32.02 b ±2.37 32.06 b ±2.25 ** + 7 43.28 a ±2.87 39.54 a ±2.56 31.07 b ±2.16 30.52 b ±2.40 ** + 14 41.27 a ±3.28 38.47 a ±3.16 30.26 b ±1.88 29.95 b ±2.06 * + 21 39.60 a ±3.02 36.81 a ±2.18 28.46 b ±1.95 28.10 b ±2.04 ** Mean 37.03 a ±1.65 34.06 a ±1.54 28.72 b ±0.86 28.61 b ±0.79 ** Prepartum Mean 31.61 a ±1.22 28.81 ab ±1.17 26.19 b ±1.00 26.23 b ±0.83 ** Postpartum Mean 42.32 a ±1.10 39.00 b ±0.76 31.06 c ±0.65 30.76 c ±0.69 ** a,b,c - Mean with different superscript in a row differ significantly*(P ≤ 0.05) **(P ≤ 0.01 Discussion Zinc plays a crucial role in reproductive physiology, and its involvement in ovulation, follicular development, and hormone regulation has been well-documented in livestock species (Abdel Monem and El-shahat 2011 ; Garner et al. 2021 ; Wada and King 1986 ). Zinc deficiency has been associated with impaired oocyte development and suboptimal reproductive performance (Liu et al. 2024 ). Several studies have reported significant improvements in reproductive traits following zinc supplementation, including reduced days to first estrus and service interval in Holstein Friesian cows (Riad et al. 2018 ), shortened postpartum estrus interval with nano ZnO supplementation at higher doses (Kundu et al. 2014 ), and improved estrus onset in goats and ewes receiving elevated dietary zinc levels ((Abdel Monem and El-shahat 2011 ; Habeeb et al. 2013 ). These findings suggest that zinc, particularly when supplied in more bioavailable forms or at higher concentrations, can positively influence reproductive efficiency. In the present study, dietary zinc supplementation especially in nano form resulted in numerically shorter postpartum interval to estrus and service period, as well as higher conception rates compared to the control group; however, these differences were not statistically significant. The observed trends are consistent with earlier reports indicating improved reproductive outcomes following zinc supplementation (Anchordoquy et al. 2019 ; El-Nour et al. 2010 ; Riad et al. 2018 ), although the magnitude of response may depend on factors such as dose, source of zinc, physiological status, baseline mineral status, and sample size. Anchordoquy et al. ( 2019 ) reported enhanced pregnancy rates in beef cows following zinc supplementation, which was attributed to increased plasma progesterone concentration and improved preovulatory follicle development, whereas other studies reported limited or no effects on conception rate following single-dose trace mineral supplementation (Vanegas et al. 2004 ). These variable responses highlight the complexity of zinc-mediated reproductive regulation. Zinc may influence reproductive performance through multiple biological pathways, including its role in vitamin A metabolism, antioxidant defense, immune modulation, and endocrine regulation. Adequate zinc status supports antioxidative immunity through superoxide dismutase activity and enhances innate immune responses, which are critical for uterine health and embryo survival during the postpartum period (Bonaventura et al. 2015 ; Fair 2015 ; Wang et al. 2013 ). Improved immune competence and metabolic adaptation during the transition period may indirectly support reproductive recovery and fertility. Reports of increased conception rates in zinc-supplemented Holstein Friesian cows and Baladi goats (El-Nour et al. 2010 ; Riad et al. 2018 ), as well as improved reproductive performance with combined trace mineral supplementation (Ahola et al. 2004 ), further support zinc’s role in reproductive efficiency. Serum Zn: The present results are consistent with previous studies showing that nano zinc supplementation leads to higher blood or serum zinc concentrations than inorganic or organic zinc sources due to its greater bioavailability (Pomport et al. 2021 ; Swain et al. 2016 ). Similar increases in plasma zinc levels following zinc supplementation during the pre- and post-calving periods have been reported in Sahiwal cows by Maurya et al. ( 2014 ). In addition, Wahyuningsih et al. (2025) observed that improved zinc status in Holstein cows was associated with enhanced reproductive performance, indicating a close relationship between zinc levels and fertility. Zinc plays a key role in the regulation of the hypothalamic–pituitary axis (Baltaci et al. 2019 ), and adequate zinc levels may support the secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), thereby influencing ovarian function (Garner et al. 2021 ). Therefore, maintaining optimal serum zinc concentrations through nano zinc supplementation may contribute to endocrine balance and improved reproductive performance in dairy cows. Plasma cholesterol: Higher serum cholesterol levels observed in nano zinc–supplemented groups highlight the important role of zinc in lipid metabolism and steroid hormone synthesis, which are critical during the periparturient period. A decline in serum cholesterol concentration towards calving, as observed in this study, has also been reported by Yadav et al. ( 2019 ) and Piccione et al. ( 2012 ). Similar findings were reported by Abayawansa et al. ( 2013 ), who observed a continuous decrease in serum cholesterol concentration until calving in buffaloes. The gradual increase in cholesterol levels after parturition may be associated with increased steroid hormone synthesis and mammary gland preparation for lactation (Patel Pankaj et al. 2020 ). Variations in cholesterol patterns, as reported by Vasantha et al. ( 2020 ), may be due to differences in breed, nutritional status, and physiological demands during early lactation. Overall, the findings suggest that nano zinc supplementation, particularly at 40 and 60 ppm levels, supports better lipid metabolism and may enhance reproductive efficiency by improving cholesterol availability for steroidogenesis for improved ovarian cyclicity and fertility. Serum AST activity increased during the prepartum period and reached peak values around the second week after calving. This is in accordance with the findings of Walter et al. ( 2022 ), who reported peak AST activity around 10 days postpartum in multiparous cows. Yadav et al. ( 2019 ) also observed variations in AST levels during early lactation, which may be attributed to breed or physiological differences. Higher AST activity during the postpartum period reflects increased hepatic load and tissue metabolism associated with milk production. The comparatively lower prepartum AST levels may be due to reduced metabolic stress, while elevated postpartum values could be related to increased tissue damage and oxidative stress following parturition, as reported by Maurya et al. ( 2014 ) and Walter et al. ( 2022 ). Both prepartum and postpartum mean AST concentrations were significantly lower in the nano zinc supplemented groups (T2 and T3), indicating a hepatoprotective effect of zinc due to its antioxidant properties and role in maintaining cell membrane integrity. Similar reductions in serum AST levels following zinc supplementation were reported by Gaafar et al. ( 2011 ) and Riad et al. ( 2018 ) in Friesian cows. However, Hegazy et al. ( 2018 ) reported increased AST levels in rats with ZnO nanoparticle supplementation, suggesting species-specific responses to nano Zn. The present study showed that serum ALT activity increased around calving, indicating higher hepatic stress during this period. Similar findings were reported by Maurya et al. ( 2014 ), who observed significantly higher ALT levels at 3 days postpartum in Sahiwal cows. The increase in ALT activity around calving may be attributed to increased lipid mobilization, higher metabolic load on the liver, and oxidative stress associated with parturition and the onset of lactation, as also reported by Angeli et al. ( 2019 ). Lower ALT concentrations during the prepartum period compared to the postpartum period were also observed, which agrees with the findings of Abdelrazek et al. ( 2018 ) and Yadav et al. ( 2019 ). Patel Pankaj et al. ( 2020 ) further reported a gradual increase in ALT levels during early lactation in crossbred cows. The decline in ALT levels after the early postpartum peak may indicate recovery of liver function following initial lactation stress. Significantly lower ALT concentrations in the nano zinc–supplemented groups (T2 and T3) suggest a hepatoprotective role of zinc. These findings are in agreement with Riad et al. ( 2018 ) and Gaafar et al. ( 2011 ), who reported reduced serum ALT levels in zinc-supplemented Friesian cows. Supplementing the diet with nano zinc (20 and 40 ppm) positively affected the concentration of zinc in serum, indicating improved bioavailability of zinc and other biochemical parameters. Nano Zn supplementation at 40 ppm in the diet of Sahiwal cows improved the other biochemical parameters, such as cholesterol, AST, and ALT. However, supplementation with 20 ppm of nano-Zn in the diet only resulted in a non-significant improvement in the postpartum interval to estrus, service period, and conception rate. Supplementation of Zn in either form is beneficial during the transition period in Sahiwal cows; however, nano-Zn supplementation has an edge over ZnO. However, to decide the feasible dose of nano Zn supplementation, a larger number of such investigations are required. Declarations Ethical approval Appropriate permission and procedure were followed for the collection of blood samples from the concerned authorities. All the procedures were performed under the relevant guidelines and regulations. The research work has been approved by the Institutional Animal Ethics Committee, College of Veterinary Science and Animal Husbandry, Anjora, Durg, Dau Shri Vasudev Chandrakar Kamdhenu Vishwavidyalay, Durg, Chhattisgarh, India. Conflict of interest The authors declare that there are no conflicts of interest. Funding The authors declare that no funds, grants, or other support were received during the preparation of this manuscript. Author contributions All authors of this paper contributed to conducting research. Methodology, data collection and analysis were performed by Arvind K. Nandanwar, Dhirendra Bhonsle, Sonali Prusty and Vandana Bhagat. The first draft of the manuscript was written by Arvind K. Nandanwar. All authors read and approved the final manuscript. Acknowledgements The authors are thankful to all respondents for sharing their responses and giving valuable information for this investigation. 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Biol Rhythm Res 52(9):1354–1371. https://doi.org/10.1080/09291016.2019.1629094 Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 24 Feb, 2026 Reviewers invited by journal 24 Feb, 2026 Editor assigned by journal 22 Feb, 2026 First submitted to journal 19 Feb, 2026 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-8908298","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":596581741,"identity":"2c5d1118-e4b5-4f51-b44f-2e78b13f60ae","order_by":0,"name":"Arvind Kumar Nandanwar","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABCUlEQVRIiWNgGAWjYJCCAwxsYNoATPKDiIQCUrRINoC0GBCyB1mLwQEEGyvgn33G8HBBGUMe/+zmjZ8L2+zyjc+vTvzwwIBBnl/sAFYtEudyDA7POMdQLHHnWLH0zLZky2033m6WADrMcObsBOzWnGFLOMzbxpDYcCPHQJp3G7OB2Y2zG0BaEgxuY9ciD9My/0aO8W/ebfUGxjPObv6BT4vBGeYDYC0bbuSYAW05bGDA37sNry2GIC085yQSN95IK7Pm/XfcQOIG7zaLBAMJnH6RO8PY/JmnzCZx3o3kzbd5zlQb8Pef3XzzR4WNPL80Du9DAw6ZnYAuQhDwHyBF9SgYBaNgFIwAAAB/f1/EQW0kWwAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0009-0003-8047-2306","institution":"Indira Gandhi Agricultural University: Indira Gandhi Krishi Vishwavidyalaya","correspondingAuthor":true,"prefix":"","firstName":"Arvind","middleName":"Kumar","lastName":"Nandanwar","suffix":""},{"id":596581742,"identity":"dfe893a7-f813-48fc-ac1e-17f296c506b9","order_by":1,"name":"Dhirendra Bhonsle","email":"","orcid":"","institution":"Chhattisgarh Kamdhenu University: Chhattisgarh Kamdhenu Vishwavidyalaya","correspondingAuthor":false,"prefix":"","firstName":"Dhirendra","middleName":"","lastName":"Bhonsle","suffix":""},{"id":596581743,"identity":"5f7e4f66-22cc-443c-bdfe-c4dc38ff10d6","order_by":2,"name":"Sonali Prusty","email":"","orcid":"","institution":"Chhattisgarh Kamdhenu University: Chhattisgarh Kamdhenu Vishwavidyalaya","correspondingAuthor":false,"prefix":"","firstName":"Sonali","middleName":"","lastName":"Prusty","suffix":""},{"id":596581744,"identity":"2125e943-7477-46c9-86f5-e36a9360cdcd","order_by":3,"name":"Vandana Bhagat","email":"","orcid":"","institution":"Chhattisgarh Kamdhenu University: Chhattisgarh Kamdhenu Vishwavidyalaya","correspondingAuthor":false,"prefix":"","firstName":"Vandana","middleName":"","lastName":"Bhagat","suffix":""}],"badges":[],"createdAt":"2026-02-18 10:26:50","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8908298/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8908298/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":103730184,"identity":"13934bac-f061-4504-8eb3-267f7a539dc7","added_by":"auto","created_at":"2026-03-02 09:07:11","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":278722,"visible":true,"origin":"","legend":"\u003cp\u003eSEM image of nano zinc oxide (NZnO)\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-8908298/v1/f637509ee40155ab33c1f95c.png"},{"id":104400258,"identity":"4d807285-2701-441e-b59b-f2cc139daa12","added_by":"auto","created_at":"2026-03-11 12:09:22","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1374196,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8908298/v1/c248c9bf-7481-458d-97db-2fed4ddcbba4.pdf"}],"financialInterests":"","formattedTitle":"Impact of Nano Zinc Supplementation During Transition Period on Reproductive Performance, Serum Biochemical Indices and Metabolic Profile in Purebred Sahiwal Cows","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAdequate intake of zinc is crucial for meeting physiological needs, maintaining animal health, and supporting reproduction. Supplementing livestock diets with zinc is a common practice to prevent or address deficiencies and to mitigate biochemical and clinical disorders. Zinc acts as a signaling factor and plays a role in DNA synthesis (Hara et al. \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). Zinc plays a pivotal role in various enzymes, which are essential for maintaining liver function. Zinc plays a crucial role in nutrient metabolism; therefore, it is necessary for growth and immune function. Lipid metabolism is compromised, and plasma cholesterol is increased in Zn deficiency (Shen et al. \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2007\u003c/span\u003e). Zinc deficiency can lead to reduced feed intake, poor feed conversion, and impaired growth performance. In mature animals, inadequate zinc levels can lead to reproductive problems. Zinc plays a crucial role in oocyte maturation, fertilization, and the development of both the embryo and placenta (Garner et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Wilson et al. \u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). Supplementation of Zn at an effective concentration modulates endocrine hormone levels during transition periods and improves reproductive efficiency in cows (Akil et al. \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2025\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe deficiency of zinc is common in ruminants, as the soil, feed, and fodder in many parts of India are reported to be zinc-deficient (Kumar et al. \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). The absorption coefficient of Zn in ruminants varies in a wide range (NRC \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2001\u003c/span\u003e), and performance is affected by the sources of Zn. Inorganic zinc has been shown to improve body weight, whereas a better effect on reproduction was observed from alternative sources of zinc (Fulton et al. 2023). Organic sources, such as Zn lysine, are recommended to have greater bioavailability than inorganic salts, like sulfate forms (Kinal and Slupczynska \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). Nano Zn is reported to have a higher absorption rate due to its higher dissolution rate in the acidic pH of the stomach and surface activity (Cho et al. \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). Nano Zn has been demonstrated to have added advantages over Zn salt, particularly in terms of feed intake, digestibility, blood Zn concentration, growth-stimulating and immunomodulatory effects, lactation performance, Zn concentrations in milk and plasma, and hematological profiles (Abdollahi et al. \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Cai et al. \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Swain et al. \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). Zinc deficiency has been frequently observed during the transition phase (Maurya et al. \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). Supplementation with nano-zinc at a reduced dose improved the quality and quantity of milk, while also helping to maintain the udder health of dairy cattle (Nandanwar et al. \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). The effect of nano-Zn supplementation on the reproductive performance of indigenous Sahiwal cattle is not well studied. The present research work was conducted to investigate the effect of supplementing nano-Zn during the transition phase of purebred Sahiwal cows on reproductive performance, hormonal profile, and blood biochemical parameters.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eAnimals, Treatments and Management\u003c/h2\u003e \u003cp\u003eTwenty-four pregnant pure-bred Sahiwal cows in first to fifth parity (300\u0026ndash;350 Kg body weight) from Bull Mother Experimental Farm (BMEF) of the College of Veterinary Science and Animal Husbandry, Durg, Chhattisgarh, were grouped randomly into four treatment groups according to parity. Cows were kept in naturally ventilated conventional barn housing with a concrete floor with paddy straw as bedding material for the duration of the trial. The pens were cleaned daily, and manure was removed periodically to keep them clean and dry. All cows in each pen had access \u003cem\u003eto ad libitum\u003c/em\u003e fresh drinking water three times daily. The experimental cows were dewormed with fenbendazole @ 7.5 mg/kg. All experimental cows were given chaffed green fodder (Hybrid Napier, Sudan, Berseem, and local grasses), dry fodder (paddy straw), and a concentrate mixture (20% Crude protein, 0.93% Ether extract) in a shed and were left for 4 hours of grazing in the morning. The cows in each group were fed individually in the pen. During the experimental period, the control group (T0) was fed a basal diet without Zn supplementation, whereas the treatment groups were given a basal diet supplemented with Zn at 40 ppm from ZnO (T1), 20 ppm from nano Zn (T2), and 40 ppm from nano Zn (T3). Nano ZnO was characterised using a particle size analyzer and a scanning electron microscope (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The treatment diets were administered during the transition period, from 30 days prior to the expected date of calving and through 30 days after the actual date of calving.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eStudied Parameters\u003c/h3\u003e\n\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eReproductive Traits\u003c/h2\u003e \u003cp\u003ePostpartum reproductive traits studied in this work included the postpartum interval to estrus (PPIE), service period, and conception rate during the first 200 days postpartum. After parturition, all experimental animals were observed regularly for signs of heat for the first 24 hours, both in the morning and evening. The interval from parturition to the onset of heat symptoms was recorded to determine the days from calving to the first heat. The dates of calving and conception were recorded for all animals to calculate the service interval. The conception rate was calculated using the formula: no. of pregnant animals X 100/no. of artificial inseminations.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eBiochemical Analysis\u003c/h3\u003e\n\u003cp\u003eFor analysis of biochemical parameters, blood samples were collected from the jugular vein in clot-activator vials in the early morning before feeding and watering. The sampling was done on -21, -14, -7, -5, -3, -1 days prepartum and on the day of calving (day 0) as well as on +\u0026thinsp;1, +3, +\u0026thinsp;5, +7, +\u0026thinsp;14, +21 postpartum from individual animals. The clot-activator vials containing blood samples were kept in the rack at a 45\u0026deg; angle at room temperature for 60\u0026ndash;120 minutes, followed by centrifugation at 1000 rpm for 10 minutes, and clear supernatant serum was decanted into pre-labelled Eppendorf tubes and deep frozen (-20\u0026deg;C) till further analysis. Serum Zn concentration was determined by an Atomic Absorption Spectrophotometer after digestion in tri acid solution (Nitric acid: Sulphuric acid: Perchloric acid- 9:1:1). Serum samples were analyzed for cholesterol, AST, ALT in a semi-auto analyser using commercial diagnostic kits (Biolab Diagnostics Pvt. Ltd., Biosar, Maharashtra, India).\u003c/p\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eFor interpretation of the results, the data were subjected to a completely randomized design (CRD) for one-way analysis of variance. The significance of differences among the groups was analyzed by Duncan's multiple range test (Snedecor and Cochran \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e1994\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eReproductive Traits\u003c/h2\u003e \u003cp\u003eThe postpartum interval to estrus (PPIE), average service period, and conception rate in Sahiwal cows under different dietary zinc supplementation levels are presented in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\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\u003eEffect of zinc supplementation on reproductive performance of Sahiwal cows\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003eGroup\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"1\" nameend=\"c7\" namest=\"c7\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParameter\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eT\u003csub\u003e0\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eSig. level\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPIE\u003c/p\u003e \u003cp\u003e(Days)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e128.83\u0026thinsp;\u0026plusmn;\u0026thinsp;12.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e113.50\u0026thinsp;\u0026plusmn;\u0026thinsp;7.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e102.66\u0026thinsp;\u0026plusmn;\u0026thinsp;8.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e108.16\u0026thinsp;\u0026plusmn;\u0026thinsp;9.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eService period (Days)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e182.66\u0026thinsp;\u0026plusmn;\u0026thinsp;10.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e165.00\u0026thinsp;\u0026plusmn;\u0026thinsp;8.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e152.00\u0026thinsp;\u0026plusmn;\u0026thinsp;6.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e158.00\u0026thinsp;\u0026plusmn;\u0026thinsp;6.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConception rate (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e36\u0026thinsp;\u0026plusmn;\u0026thinsp;11.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e44\u0026thinsp;\u0026plusmn;\u0026thinsp;13.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e62.5\u0026thinsp;\u0026plusmn;\u0026thinsp;12.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e55\u0026thinsp;\u0026plusmn;\u0026thinsp;11.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003ePostpartum Interval to Estrus\u003c/h3\u003e\n\u003cp\u003eThe mean values of postpartum interval to estrus (PPIE) in T0, T1, T2, and T3 groups were 128.83, 113.50, 102.66, and 108.16 days, respectively. There was no significant difference between the treatment and control groups. However, compared to the control group, zinc supplementation reduced PPIE by 11.09%, 20.31%, and 16.04% in T1, T2, and T3, respectively.\u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eService Period Interval\u003c/h2\u003e \u003cp\u003eThe average interval of service period of Sahiwal cows was 182.66, 165.00, 152.00, and 158.00 days in T0, T1, T2, and T3 groups, respectively. Zinc supplementation in T1, T2, and T3 groups reduced the service period by 9.66%, 16.78% and 13.50%, respectively, compared to the control group. However, there was no significant difference between the treatment and control groups.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eConception Rate\u003c/h2\u003e \u003cp\u003eThe conception rate averaged 36%, 44%, 62.5% and 55% in T0, T1, T2, and T3 groups, respectively. There was a non-significant difference in the mean values of conception rate among the groups of Sahiwal cows. However, the nano zinc-supplemented groups (T2 and T3) showed a better conception rate compared to the control and inorganic zinc-supplemented groups.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eSerum Zn\u003c/h2\u003e \u003cp\u003eThe effect of different zinc sources on the concentration of serum zinc in Sahiwal cows is shown in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. Serum zinc concentration was significantly affected by the treatments and the overall experimental period (P\u0026thinsp;\u0026le;\u0026thinsp;0.05). The highest concentration was recorded in the 40 ppm nano zinc (T3) group of Sahiwal cows. The concentration of serum zinc gradually decreased towards calving and reached its lowest level on the third day postpartum across all treatment and control groups. Significantly higher (P\u0026thinsp;\u0026le;\u0026thinsp;0.05 and P\u0026thinsp;\u0026le;\u0026thinsp;0.01) serum zinc concentrations were observed at 1, 3, and 7 days prepartum, as well as at calving and on 5, 7, 14, and 21 days postpartum in the 40 ppm nano zinc group compared to other groups. Overall, the mean serum zinc concentration during the prepartum period was higher than during the postpartum period across all treatments.\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\u003eMean values (\u0026plusmn;\u0026thinsp;SE) of serum zinc (ppm) in Sahiwal cows\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 \u003cp\u003ePeriods of observations\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003eSerum zinc (ppm) in Sahiwal cows\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSig. level\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDays relative to calving\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eT\u003csub\u003e0\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.55\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.62\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.66\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.71\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.50\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.55\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.62\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.73\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.34\u003csup\u003ec\u003c/sup\u003e\u0026plusmn;0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.39\u003csup\u003ebc\u003c/sup\u003e\u0026plusmn;0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.54\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.59\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.25\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.31\u0026thinsp;\u0026plusmn;\u0026thinsp;0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.38\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.44\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.05\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.18\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.26\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.31\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.02\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.06\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.17\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.20\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAt Calving\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.96\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.98\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.13\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.23\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.90\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.93\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.04\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.15\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.80\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.85\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.93\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.05\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.89\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.93\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.04\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.14\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.93\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.96\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.07\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.21\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.08\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.15\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.32\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.45\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.14\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.19\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.54\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.57\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.10\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.16\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.28\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.36\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrepartum Mean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.35\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.43\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.49\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePostpartum Mean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.95\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.00\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.15\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;0.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.26\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003e\u003csup\u003ea,b, c\u003c/sup\u003e- Mean with different superscript in a row differ significantly *(P\u0026thinsp;\u0026le;\u0026thinsp;0.05), **(P\u0026thinsp;\u0026le;\u0026thinsp;0.01)\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\u003eCholesterol\u003c/h2\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\u003eMean values (\u0026plusmn;\u0026thinsp;SE) of cholesterol (mg/dl) in Sahiwal cows\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 \u003cp\u003ePeriods of observations\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003eCholesterol (mg/dl) in Sahiwal cows\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSig. level\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDays relative to calving\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eT\u003csub\u003e0\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e116.33\u0026thinsp;\u0026plusmn;\u0026thinsp;2.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e118.62\u0026thinsp;\u0026plusmn;\u0026thinsp;2.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e119.02\u0026thinsp;\u0026plusmn;\u0026thinsp;2.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e121.18\u0026thinsp;\u0026plusmn;\u0026thinsp;3.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e109.00\u0026thinsp;\u0026plusmn;\u0026thinsp;3.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e113.77\u0026thinsp;\u0026plusmn;\u0026thinsp;2.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e116.09\u0026thinsp;\u0026plusmn;\u0026thinsp;2.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e118.01\u0026thinsp;\u0026plusmn;\u0026thinsp;2.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e111.69\u0026thinsp;\u0026plusmn;\u0026thinsp;2.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e109.16\u0026thinsp;\u0026plusmn;\u0026thinsp;2.73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e111.09\u0026thinsp;\u0026plusmn;\u0026thinsp;2.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e110.00\u0026thinsp;\u0026plusmn;\u0026thinsp;3.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e103.61\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e105.13\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e107.38\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e113.06\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e98.10\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100.73\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e104.08\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;1.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e107.00\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e97.04\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e99.03\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e103.81\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e105.16\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAt Calving\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e96.90\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e99.27\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e102.69\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e108.00\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e99.24\u0026thinsp;\u0026plusmn;\u0026thinsp;1.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e101.95\u0026thinsp;\u0026plusmn;\u0026thinsp;2.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e106.03\u0026thinsp;\u0026plusmn;\u0026thinsp;2.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e108.00\u0026thinsp;\u0026plusmn;\u0026thinsp;2.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e105.05\u003csup\u003ec\u003c/sup\u003e\u0026plusmn;2.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e103.55\u003csup\u003ebc\u003c/sup\u003e\u0026plusmn;2.24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e120.02\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;3.24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e112.66\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e105.10\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e112.01\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e118.01\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;3.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e110.17\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;3.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e116.00\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e109.30\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;3.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e129.07\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;3.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e128.06\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;3.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e121.01\u003csup\u003ec\u003c/sup\u003e\u0026plusmn;3.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e124.08\u003csup\u003ebc\u003c/sup\u003e\u0026plusmn;3.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e133.03\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e136.03\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e129.02\u0026thinsp;\u0026plusmn;\u0026thinsp;3.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e135.70\u0026thinsp;\u0026plusmn;\u0026thinsp;3.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e138.70\u0026thinsp;\u0026plusmn;\u0026thinsp;2.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e141.86\u0026thinsp;\u0026plusmn;\u0026thinsp;3.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e108.31\u0026thinsp;\u0026plusmn;\u0026thinsp;2.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e110.17\u0026thinsp;\u0026plusmn;\u0026thinsp;2.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e116.07\u0026thinsp;\u0026plusmn;\u0026thinsp;3.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e116.86\u0026thinsp;\u0026plusmn;\u0026thinsp;3.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrepartum Mean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e105.96\u0026thinsp;\u0026plusmn;\u0026thinsp;3.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e107.74\u0026thinsp;\u0026plusmn;\u0026thinsp;3.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e110.24\u0026thinsp;\u0026plusmn;\u0026thinsp;2.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e112.40\u0026thinsp;\u0026plusmn;\u0026thinsp;2.55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePostpartum Mean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e112.57\u0026thinsp;\u0026plusmn;\u0026thinsp;4.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e114.43\u0026thinsp;\u0026plusmn;\u0026thinsp;5.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e124.14\u0026thinsp;\u0026plusmn;\u0026thinsp;4.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e122.79\u0026thinsp;\u0026plusmn;\u0026thinsp;5.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003e\u003csup\u003ea,b,c\u003c/sup\u003e- Mean with different superscript in a row differ significantly*(P\u0026thinsp;\u0026le;\u0026thinsp;0.05) **(P\u0026thinsp;\u0026le;\u0026thinsp;0.01)\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe mean serum cholesterol concentration during the transition period in Sahiwal cows under different dietary zinc supplementation is presented in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. The mean cholesterol concentration in Sahiwal cows for the T0, T1, T2, and T3 groups was 108.31, 110.17, 116.07, and 116.86 mg/dL, respectively. The prepartum means of cholesterol in the T0, T1, T2, and T3 groups were 105.96\u0026thinsp;\u0026plusmn;\u0026thinsp;3.14, 107.74\u0026thinsp;\u0026plusmn;\u0026thinsp;3.10, 110.24\u0026thinsp;\u0026plusmn;\u0026thinsp;2.57, and 112.40\u0026thinsp;\u0026plusmn;\u0026thinsp;2.55 mg/dL, respectively. The postpartum values were 112.57, 114.43, 124.14, and 122.79 mg/dL, respectively. The overall cholesterol concentration during the prepartum period was lower than that during the postpartum period in all groups. The treatment-related differences were more pronounced during early and mid-lactation (3, 5, 7 and 14 postpartum). During these periods, cows in T2 and T3 exhibited significantly higher cholesterol concentrations compared to T0 and T1. Decline in serum cholesterol concentration approaching calving, followed by a gradual and significant increase during the postpartum period, with treatment-related differences being more pronounced during early and mid-lactation.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eAspartate Aminotransferase (AST)\u003c/h2\u003e \u003cp\u003eThe AST enzyme in the liver plays a role in the metabolism of amino acids. The AST test may help diagnose and monitor liver problems. These enzymes are released when the liver is damaged and the concentration of serum AST is increased. The mean serum concentration of AST during the transition period in Sahiwal cows under different dietary zinc supplementation has been shown in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e. The mean concentration of AST of Sahiwal cows in T0, T1, T2, and T3 groups was 90.99\u0026thinsp;\u0026plusmn;\u0026thinsp;1.89, 84.61\u0026thinsp;\u0026plusmn;\u0026thinsp;1.34, 81.46\u0026thinsp;\u0026plusmn;\u0026thinsp;1.14, and 79.19\u0026thinsp;\u0026plusmn;\u0026thinsp;1.38 U/L, respectively. The prepartum mean of AST of Sahiwal cows in T0, T1, T2 and T3 groups were 85.15\u0026thinsp;\u0026plusmn;\u0026thinsp;1.91, 80.88\u0026thinsp;\u0026plusmn;\u0026thinsp;1.85, 78.53\u0026thinsp;\u0026plusmn;\u0026thinsp;1.85 and 75.39\u0026thinsp;\u0026plusmn;\u0026thinsp;1.87 U/L, respectively and the postpartum values were 96.64\u0026thinsp;\u0026plusmn;\u0026thinsp;1.29, 88.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.81, 84.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.28 and 83.00\u0026thinsp;\u0026plusmn;\u0026thinsp;0.77 U/L, respectively. Significant differences were observed in overall mean as well as postpartum and prepartum mean values. Significant differences were observed in the overall mean, as well as in prepartum and postpartum mean values among the groups. The prepartum and postpartum mean concentrations of AST were found to be significantly (P\u0026thinsp;\u0026le;\u0026thinsp;0.05 and P\u0026thinsp;\u0026le;\u0026thinsp;0.01, respectively) lower in the T3 and T2 groups. The mean concentration of serum AST was significantly (P\u0026thinsp;\u0026le;\u0026thinsp;0.01) lower in the T3 group, followed by the T2 and T1 groups, compared to the control group. Increased AST activity from prepartum to postpartum period, with consistently higher enzyme activity in T0, suggests greater metabolic and hepatic load around calving and early lactation without Zn supplementation.\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\u003eMean values (\u0026plusmn;\u0026thinsp;SE) of AST conc. (U/L) in Sahiwal cows\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 \u003cp\u003ePeriods of observations\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003eAST (U/L) in Sahiwal cows\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSig. level\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDays relative to calving\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eT\u003csub\u003e0\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e76.24\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;1.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e72.80\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;1.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e70.05\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e67.05\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e83.74\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e78.38\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;1.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e76.72\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e73.31\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e87.57\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e83.00\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e80.28\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e77.03\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e87.17\u0026thinsp;\u0026plusmn;\u0026thinsp;2.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e82.82\u0026thinsp;\u0026plusmn;\u0026thinsp;3.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e81.05\u0026thinsp;\u0026plusmn;\u0026thinsp;1.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e76.82\u0026thinsp;\u0026plusmn;\u0026thinsp;2.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e87.42\u0026thinsp;\u0026plusmn;\u0026thinsp;1.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e83.25\u0026thinsp;\u0026plusmn;\u0026thinsp;2.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e81.38\u0026thinsp;\u0026plusmn;\u0026thinsp;2.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e79.09\u0026thinsp;\u0026plusmn;\u0026thinsp;2.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e88.78\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e85.06\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e81.71\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e79.04\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAt Calving\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e92.17\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;3.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e85.71\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;3.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e82.10\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;3.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e79.24\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e93.14\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e85.13\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e83.04\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e80.40\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e95.18\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e87.01\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e84.25\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e82.06\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e95.18\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;1.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e87.86\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e84.74\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e83.05\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e95.18\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;1.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e88.91\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e84.81\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e85.37\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e101.12\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e91.03\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e84.81\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e85.01\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;3.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100.08\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e89.02\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e84.06\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e82.12\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;3.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e90.99\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;1.89\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e84.61\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e81.46\u003csup\u003ebc\u003c/sup\u003e\u0026plusmn;1.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e79.19\u003csup\u003ec\u003c/sup\u003e\u0026plusmn;1.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrepartum Mean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e85.15\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;1.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e80.88\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;1.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e78.53\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e75.39\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePostpartum Mean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e96.64\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;1.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e88.16\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e84.28\u003csup\u003ec\u003c/sup\u003e\u0026plusmn;0.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e83.00\u003csup\u003ec\u003c/sup\u003e\u0026plusmn;0.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003e\u003csup\u003ea,b,c\u003c/sup\u003e- Mean with different superscript in a row differ significantly*(P\u0026thinsp;\u0026le;\u0026thinsp;0.05) **(P\u0026thinsp;\u0026le;\u0026thinsp;0.01)\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eAlanine Aminotransferase (ALT)\u003c/h2\u003e \u003cp\u003eThe function of ALT is to convert alanine into pyruvate for cellular energy production. High levels of these enzymes can be a sign that the liver is injured. The mean serum concentration of ALT during the transition period in Sahiwal cows under different dietary zinc supplementation has been shown in Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e. The mean concentration of ALT of Sahiwal cows in T0, T1, T2, and T3 groups was 37.03\u0026thinsp;\u0026plusmn;\u0026thinsp;1.65, 34.06\u0026thinsp;\u0026plusmn;\u0026thinsp;1.54, 28.72\u0026thinsp;\u0026plusmn;\u0026thinsp;0.86, and 28.61\u0026thinsp;\u0026plusmn;\u0026thinsp;0.79 U/L, respectively. The serum enzyme ALT level increased gradually up to 3 days postpartum, then remained stable from 21 days into the prepartum period, followed by a decline thereafter in all treatment groups. The overall ALT concentration during the prepartum period was lower than that during the postpartum period in all groups. The prepartum and postpartum mean concentration of ALT was found significantly (P\u0026thinsp;\u0026le;\u0026thinsp;0.01) lower in the T2 and T3 groups. There was a significant variation in the mean serum ALT concentration of Sahiwal cows across the treatments (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01), with the T3 and T2 groups having significantly lower concentrations (P\u0026thinsp;\u0026le;\u0026thinsp;0.01), followed by the T1 group, and then the control group.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMean values (\u0026plusmn;\u0026thinsp;SE) of ALT conc. (U/L) in Sahiwal cows\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 \u003cp\u003ePeriods of observations\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003eALT (U/L) in Sahiwal cows\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSig. level\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDays relative to calving\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eT\u003csub\u003e0\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28.10\u0026thinsp;\u0026plusmn;\u0026thinsp;2.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25.61\u0026thinsp;\u0026plusmn;\u0026thinsp;1.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e23.82\u0026thinsp;\u0026plusmn;\u0026thinsp;1.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e23.61\u0026thinsp;\u0026plusmn;\u0026thinsp;0.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29.40\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;1.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e26.82\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e22.92\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e23.90\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30.20\u0026thinsp;\u0026plusmn;\u0026thinsp;2.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e27.78\u0026thinsp;\u0026plusmn;\u0026thinsp;1.86\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e25.88\u0026thinsp;\u0026plusmn;\u0026thinsp;1.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e26.96\u0026thinsp;\u0026plusmn;\u0026thinsp;1.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e31.80\u0026thinsp;\u0026plusmn;\u0026thinsp;2.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28.91\u0026thinsp;\u0026plusmn;\u0026thinsp;1.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e27.05\u0026thinsp;\u0026plusmn;\u0026thinsp;2.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e26.53\u0026thinsp;\u0026plusmn;\u0026thinsp;1.89\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e34.07\u0026thinsp;\u0026plusmn;\u0026thinsp;2.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30.05\u0026thinsp;\u0026plusmn;\u0026thinsp;2.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e28.42\u0026thinsp;\u0026plusmn;\u0026thinsp;1.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e27.82\u0026thinsp;\u0026plusmn;\u0026thinsp;1.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e-1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e36.09\u0026thinsp;\u0026plusmn;\u0026thinsp;2.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33.74\u0026thinsp;\u0026plusmn;\u0026thinsp;2.73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e29.05\u0026thinsp;\u0026plusmn;\u0026thinsp;1.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e28.61\u0026thinsp;\u0026plusmn;\u0026thinsp;1.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAt Calving\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e37.85\u0026thinsp;\u0026plusmn;\u0026thinsp;2.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e35.90\u0026thinsp;\u0026plusmn;\u0026thinsp;3.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e30.12\u0026thinsp;\u0026plusmn;\u0026thinsp;2.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e30.01\u0026thinsp;\u0026plusmn;\u0026thinsp;1.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39.35\u0026thinsp;\u0026plusmn;\u0026thinsp;2.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e37.18\u0026thinsp;\u0026plusmn;\u0026thinsp;1.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e31.39\u0026thinsp;\u0026plusmn;\u0026thinsp;2.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e31.00\u0026thinsp;\u0026plusmn;\u0026thinsp;2.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e46.08\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;3.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e41.68\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;3.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e33.18\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e32.94\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e44.38\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;3.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40.36\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;2.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e32.02\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e32.06\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e43.28\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e39.54\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e31.07\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e30.52\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e41.27\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;3.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e38.47\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;3.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e30.26\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e29.95\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e+\u0026thinsp;21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39.60\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;3.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e36.81\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;2.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e28.46\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e28.10\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;2.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e37.03\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;1.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e34.06\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;1.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e28.72\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.86\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e28.61\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrepartum Mean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e31.61\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;1.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28.81\u003csup\u003eab\u003c/sup\u003e\u0026plusmn;1.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e26.19\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;1.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e26.23\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePostpartum Mean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e42.32\u003csup\u003ea\u003c/sup\u003e\u0026plusmn;1.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e39.00\u003csup\u003eb\u003c/sup\u003e\u0026plusmn;0.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e31.06\u003csup\u003ec\u003c/sup\u003e\u0026plusmn;0.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e30.76\u003csup\u003ec\u003c/sup\u003e\u0026plusmn;0.69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003e\u003csup\u003ea,b,c\u003c/sup\u003e- Mean with different superscript in a row differ significantly*(P\u0026thinsp;\u0026le;\u0026thinsp;0.05) **(P\u0026thinsp;\u0026le;\u0026thinsp;0.01\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eZinc plays a crucial role in reproductive physiology, and its involvement in ovulation, follicular development, and hormone regulation has been well-documented in livestock species (Abdel Monem and El-shahat \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2011\u003c/span\u003e; Garner et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Wada and King \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e1986\u003c/span\u003e). Zinc deficiency has been associated with impaired oocyte development and suboptimal reproductive performance (Liu et al. \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). Several studies have reported significant improvements in reproductive traits following zinc supplementation, including reduced days to first estrus and service interval in Holstein Friesian cows (Riad et al. \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), shortened postpartum estrus interval with nano ZnO supplementation at higher doses (Kundu et al. \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2014\u003c/span\u003e), and improved estrus onset in goats and ewes receiving elevated dietary zinc levels ((Abdel Monem and El-shahat \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2011\u003c/span\u003e; Habeeb et al. \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). These findings suggest that zinc, particularly when supplied in more bioavailable forms or at higher concentrations, can positively influence reproductive efficiency.\u003c/p\u003e \u003cp\u003eIn the present study, dietary zinc supplementation especially in nano form resulted in numerically shorter postpartum interval to estrus and service period, as well as higher conception rates compared to the control group; however, these differences were not statistically significant. The observed trends are consistent with earlier reports indicating improved reproductive outcomes following zinc supplementation (Anchordoquy et al. \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; El-Nour et al. \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2010\u003c/span\u003e; Riad et al. \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), although the magnitude of response may depend on factors such as dose, source of zinc, physiological status, baseline mineral status, and sample size. Anchordoquy et al. (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2019\u003c/span\u003e) reported enhanced pregnancy rates in beef cows following zinc supplementation, which was attributed to increased plasma progesterone concentration and improved preovulatory follicle development, whereas other studies reported limited or no effects on conception rate following single-dose trace mineral supplementation (Vanegas et al. \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e2004\u003c/span\u003e). These variable responses highlight the complexity of zinc-mediated reproductive regulation.\u003c/p\u003e \u003cp\u003eZinc may influence reproductive performance through multiple biological pathways, including its role in vitamin A metabolism, antioxidant defense, immune modulation, and endocrine regulation. Adequate zinc status supports antioxidative immunity through superoxide dismutase activity and enhances innate immune responses, which are critical for uterine health and embryo survival during the postpartum period (Bonaventura et al. \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Fair \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Wang et al. \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). Improved immune competence and metabolic adaptation during the transition period may indirectly support reproductive recovery and fertility. Reports of increased conception rates in zinc-supplemented Holstein Friesian cows and Baladi goats (El-Nour et al. \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2010\u003c/span\u003e; Riad et al. \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), as well as improved reproductive performance with combined trace mineral supplementation (Ahola et al. \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2004\u003c/span\u003e), further support zinc\u0026rsquo;s role in reproductive efficiency.\u003c/p\u003e \u003cp\u003eSerum Zn: The present results are consistent with previous studies showing that nano zinc supplementation leads to higher blood or serum zinc concentrations than inorganic or organic zinc sources due to its greater bioavailability (Pomport et al. \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Swain et al. \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). Similar increases in plasma zinc levels following zinc supplementation during the pre- and post-calving periods have been reported in Sahiwal cows by Maurya et al. (\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). In addition, Wahyuningsih et al. (2025) observed that improved zinc status in Holstein cows was associated with enhanced reproductive performance, indicating a close relationship between zinc levels and fertility. Zinc plays a key role in the regulation of the hypothalamic\u0026ndash;pituitary axis (Baltaci et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2019\u003c/span\u003e), and adequate zinc levels may support the secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), thereby influencing ovarian function (Garner et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Therefore, maintaining optimal serum zinc concentrations through nano zinc supplementation may contribute to endocrine balance and improved reproductive performance in dairy cows.\u003c/p\u003e \u003cp\u003ePlasma cholesterol: Higher serum cholesterol levels observed in nano zinc\u0026ndash;supplemented groups highlight the important role of zinc in lipid metabolism and steroid hormone synthesis, which are critical during the periparturient period. A decline in serum cholesterol concentration towards calving, as observed in this study, has also been reported by Yadav et al. (\u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e2019\u003c/span\u003e) and Piccione et al. (\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2012\u003c/span\u003e). Similar findings were reported by Abayawansa et al. (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2013\u003c/span\u003e), who observed a continuous decrease in serum cholesterol concentration until calving in buffaloes. The gradual increase in cholesterol levels after parturition may be associated with increased steroid hormone synthesis and mammary gland preparation for lactation (Patel Pankaj et al. \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Variations in cholesterol patterns, as reported by Vasantha et al. (\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), may be due to differences in breed, nutritional status, and physiological demands during early lactation. Overall, the findings suggest that nano zinc supplementation, particularly at 40 and 60 ppm levels, supports better lipid metabolism and may enhance reproductive efficiency by improving cholesterol availability for steroidogenesis for improved ovarian cyclicity and fertility.\u003c/p\u003e \u003cp\u003eSerum AST activity increased during the prepartum period and reached peak values around the second week after calving. This is in accordance with the findings of Walter et al. (\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2022\u003c/span\u003e), who reported peak AST activity around 10 days postpartum in multiparous cows. Yadav et al. (\u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e2019\u003c/span\u003e) also observed variations in AST levels during early lactation, which may be attributed to breed or physiological differences. Higher AST activity during the postpartum period reflects increased hepatic load and tissue metabolism associated with milk production. The comparatively lower prepartum AST levels may be due to reduced metabolic stress, while elevated postpartum values could be related to increased tissue damage and oxidative stress following parturition, as reported by Maurya et al. (\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2014\u003c/span\u003e) and Walter et al. (\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Both prepartum and postpartum mean AST concentrations were significantly lower in the nano zinc supplemented groups (T2 and T3), indicating a hepatoprotective effect of zinc due to its antioxidant properties and role in maintaining cell membrane integrity. Similar reductions in serum AST levels following zinc supplementation were reported by Gaafar et al. (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2011\u003c/span\u003e) and Riad et al. (\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) in Friesian cows. However, Hegazy et al. (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) reported increased AST levels in rats with ZnO nanoparticle supplementation, suggesting species-specific responses to nano Zn.\u003c/p\u003e \u003cp\u003eThe present study showed that serum ALT activity increased around calving, indicating higher hepatic stress during this period. Similar findings were reported by Maurya et al. (\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2014\u003c/span\u003e), who observed significantly higher ALT levels at 3 days postpartum in Sahiwal cows. The increase in ALT activity around calving may be attributed to increased lipid mobilization, higher metabolic load on the liver, and oxidative stress associated with parturition and the onset of lactation, as also reported by Angeli et al. (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). Lower ALT concentrations during the prepartum period compared to the postpartum period were also observed, which agrees with the findings of Abdelrazek et al. (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) and Yadav et al. (\u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). Patel Pankaj et al. (\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) further reported a gradual increase in ALT levels during early lactation in crossbred cows. The decline in ALT levels after the early postpartum peak may indicate recovery of liver function following initial lactation stress. Significantly lower ALT concentrations in the nano zinc\u0026ndash;supplemented groups (T2 and T3) suggest a hepatoprotective role of zinc. These findings are in agreement with Riad et al. (\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) and Gaafar et al. (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2011\u003c/span\u003e), who reported reduced serum ALT levels in zinc-supplemented Friesian cows. Supplementing the diet with nano zinc (20 and 40 ppm) positively affected the concentration of zinc in serum, indicating improved bioavailability of zinc and other biochemical parameters. Nano Zn supplementation at 40 ppm in the diet of Sahiwal cows improved the other biochemical parameters, such as cholesterol, AST, and ALT. However, supplementation with 20 ppm of nano-Zn in the diet only resulted in a non-significant improvement in the postpartum interval to estrus, service period, and conception rate. Supplementation of Zn in either form is beneficial during the transition period in Sahiwal cows; however, nano-Zn supplementation has an edge over ZnO. However, to decide the feasible dose of nano Zn supplementation, a larger number of such investigations are required.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eEthical approval\u003c/h2\u003e \u003cp\u003eAppropriate permission and procedure were followed for the collection of blood samples from the concerned authorities. All the procedures were performed under the relevant guidelines and regulations. The research work has been approved by the Institutional Animal Ethics Committee, College of Veterinary Science and Animal Husbandry, Anjora, Durg, Dau Shri Vasudev Chandrakar Kamdhenu Vishwavidyalay, Durg, Chhattisgarh, India.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConflict of interest\u003c/strong\u003e \u003cp\u003eThe authors declare that there are no conflicts of interest.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThe authors declare that no funds, grants, or other support were received during the preparation of this manuscript.\u003c/p\u003e\u003ch2\u003eAuthor contributions\u003c/h2\u003e \u003cp\u003eAll authors of this paper contributed to conducting research. Methodology, data collection and analysis were performed by Arvind K. Nandanwar, Dhirendra Bhonsle, Sonali Prusty and Vandana Bhagat. The first draft of the manuscript was written by Arvind K. Nandanwar. All authors read and approved the final manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e \u003cp\u003eThe authors are thankful to all respondents for sharing their responses and giving valuable information for this investigation. All the authors are also thankful to those who assisted directly and indirectly for the fruitful outcome of this study.\u003c/p\u003e\u003ch2\u003eData availability\u003c/h2\u003e \u003cp\u003eAll data generated in this study are included in this published article.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAnchordoquy JM, Anchordoquy JP, Galarza EM, Farnetano NA, Giuliodori MJ, Nikoloff N, Fazzio LE, Furnus CC (2019) Parenteral zinc supplementation increases pregnancy rates in beef cows. 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Biol Rhythm Res 52(9):1354\u0026ndash;1371. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1080/09291016.2019.1629094\u003c/span\u003e\u003cspan address=\"10.1080/09291016.2019.1629094\" 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":false,"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":"Nano zinc, Transition period, Sahiwal, Zinc status, Liver function, Conception rate","lastPublishedDoi":"10.21203/rs.3.rs-8908298/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8908298/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eMicronutrients are essential for physiological functions and are especially crucial during the transition period. Zinc is one of such nutrients that plays a vital role in metabolism, immunity, endocrine regulation, reproductive physiology, and uterine health. Nano-zinc, due to its superior bioavailability, offers improved physiological benefits at lower supplementation levels. Twenty-four pregnant purebred Sahiwal cows were randomly assigned to four groups receiving a balanced diet without zinc (T0), zinc oxide at 40 ppm (T1), and nano zinc oxide at 20 ppm (T2) and 40 ppm (T3). Nano-zinc supplementation did not significantly affect reproductive performance but showed a non-significant reduction in the postpartum interval to estrus by 11\u0026ndash;20%, and service period by 9.66\u0026ndash;16.78%, and an increase in the conception rate compared to other treatments. The concentration of serum zinc varied significantly (P\u0026thinsp;\u0026le;\u0026thinsp;0.05) among treatments, with the highest levels observed in the 40 ppm nano-zinc group during both the prepartum and postpartum periods, despite its superior bioavailability. Administration of nano zinc-supplemented groups caused a non-significant increase in cholesterol concentration as compared to other groups and contributed to better reproductive performance. Compared to the different treatments group feeding with nano zinc at 40 ppm showed significantly (P\u0026thinsp;\u0026le;\u0026thinsp;0.01) lower concentrations of AST and ALT during prepartum and postpartum periods.\u003c/p\u003e","manuscriptTitle":"Impact of Nano Zinc Supplementation During Transition Period on Reproductive Performance, Serum Biochemical Indices and Metabolic Profile in Purebred Sahiwal Cows","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-02 09:07:06","doi":"10.21203/rs.3.rs-8908298/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"","date":"2026-02-25T00:52:57+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-02-25T00:40:15+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-02-23T02:34:56+00:00","index":"","fulltext":""},{"type":"submitted","content":"Tropical Animal Health and Production","date":"2026-02-19T05:51:21+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":"cced00d9-e2ce-4488-8deb-deb82ff33023","owner":[],"postedDate":"March 2nd, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-05T03:38:08+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-02 09:07:06","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8908298","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8908298","identity":"rs-8908298","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}