Effects of Vitamin E on Stress Resorption, Lipid Profile and Reproductive Performance of Sokoto Red Goats

Abstract

Vitamin E (α-tocopherol) plays a critical role in animal nutrition as an antioxidant, contributing to anti-inflammatory responses, immune function, and gene expression regulation. This study aimed to determine the optimal dietary level of vitamin E to alleviate the effects of environmental stress in Sokoto Red Goats transported from their native dry savannah belt to the humid derived savanna belt of Nigeria, and to evaluate its effects on physiological stress indicators, serum lipid profile, and reproductive function. Thirty growing Sokoto Red Goats of mixed sexes, aged 12 to 15 months, were used in the experiment. Following a two-week quarantine period during which all animals received long-acting oxytetracycline and ivermectin, they were allotted into five treatment groups (A, B, C, D, and E) with two replicates each, balanced for body weight in a completely randomized design. Dietary vitamin E was supplemented at 0, 3, 6, 9, and 12 g/kg of feed for treatments A through E, respectively. Animals had unrestricted access to feed, forages (Panicum maximum and Pennisetum purpureum), and water for a period of three months. Body weight, respiration rate, pulse rate, and rectal temperature were recorded fortnightly. Blood was collected via jugular venipuncture for serum and hormonal assays. Vitamin E supplementation significantly (p<0.05) reduced respiration and pulse rates, with rectal temperature remaining within the normal physiological range for goats. Significant (p<0.05) reductions were observed in total cholesterol, low-density lipoprotein (LDL), and triglycerides, while very low-density lipoprotein cholesterol (VLDL) showed a significant increase. Reproductive function was also significantly (p<0.05) improved, with elevated oestrogen and testosterone levels, enhanced sperm motility, progressive motility, and acrosome integrity, alongside significant reductions in sperm abnormalities and dead spermatozoa. It was concluded that the inclusion of 6 g vitamin E per kg of feed yielded optimal performance in Sokoto Red Goats under transport and environmental stress conditions.