Abstract
The experiment was conducted at the Department of Animal Science, Livestock Teaching and Research Farm, Usmanu Danfodiyo University, Sokoto, Nigeria. The objective was to evaluate the effects of different modes of vitamin E supplementation on adaptability and stress biomarkers in Uda rams under semi-arid conditions. Twelve yearling Uda rams (18–23 kg BW) were randomly assigned to three treatment groups (n = 4 per group; experimental unit = ram) in a Completely Randomized Design (CRD) with four replications. Vitamin E (DL-α-tocopheryl acetate, Shaanxi Bieyouth Biotech Co. Ltd., China) was supplemented at 40g/kg DM in feed or 40g/L DM in water. The feeding trial lasted for seven weeks (41 days). The basal diet contained 2509 Kcal/kg metabolizable energy, 17.14% crude protein, 19.46% crude fibre, and no additional selenium or carotenoid supplementation.
Feed and water intake were recorded daily. Stress biomarkers (cortisol, prolactin, triiodothyronine [T3], and thyroxine [T4]), antioxidant activity (malondialdehyde [MDA] measured using the TBARS method, superoxide dismutase [SOD] determined with a commercial assay kit, and total antioxidant capacity), and stress indicators (pulse rate, rectal temperature, and respiratory rate) were measured weekly at 8:00 am and 3:00 pm. Data were analyzed using ANOVA under a CRD model, and treatment means were separated using the Least Significant Difference (LSD) test at p < 0.05.
Significant changes were observed in cortisol (55.33, 45.33, 52.66 ng/ml), T4 (8.43, 6.67, 6.57 µg/ml), MDA (2.86, 1.88, 1.89 nmol/ml), and respiratory rate (42.70, 26.00, 31.20 bpm), while other parameters showed no significant differences. Vitamin E supplementation reduced cortisol levels (p < 0.05) when provided in feed, decreased T4 levels when supplemented in water (p < 0.05), and lowered MDA concentrations in both feed and water treatments (p < 0.05), indicating reduced oxidative stress. SOD activity increased when vitamin E was supplemented in water (p < 0.05), whereas prolactin, T3, TAC, pulse rate, and rectal temperature were unaffected.
From these results, we can conclude that Vitamin E supplementation, particularly through feed, effectively reduces stress biomarkers and enhances antioxidant activity in Uda rams, although its effects on thyroid hormones and prolactin require further investigation.
Keywords
Vitamin E; Stress Biomarkers; stress indicators; Antioxidant activity; Uda Ram.
All procedures were conducted in accordance with animal welfare standards and approved by the Department of Animal Science, Faculty of Agricultural Sciences, Usmanu Danfodiyo University Sokoto.
