Evaluation of Selenium Dose Effects on Haematology, Serum Chemistry, and Stress Markers in Uda Rams

Abstract

Selenium supplementation has been reported to improve haematological indices, enhance antioxidant defence systems, and modulate stress biomarkers in livestock. This study investigated the effects of graded selenium supplementation on haematology, serum biochemistry, and stress biomarkers in Uda rams. Fifteen yearling rams were randomly assigned to three groups: control (0 mg/kg), 12 mg/kg, and 15 mg/kg sodium selenite, in a completely randomised design. Blood samples were collected to evaluate haematological indices, serum biochemical parameters, and hormonal stress markers, while physiological stress indicators, including pulse rate, respiratory rate, and rectal temperature, were monitored. Selenium supplementation significantly (p<0.05) enhanced haemoglobin concentration, packed cell volume, red blood cell count, and serum globulin levels, while modulating lipid profiles and oxidative stress markers. Rams receiving 15 mg/kg selenium exhibited the lowest cortisol and malondialdehyde levels, indicating improved stress resilience and antioxidant protection. No adverse effects were observed on liver enzymes, albumin, total protein, or electrolyte balance. Additionally, selenium influenced thyroid hormones and prolactin in a dose-dependent manner. The findings suggest that dietary selenium at 12–15 mg/kg optimally improves haematological health, immune function, and stress adaptability in Uda rams, supporting its use as a dietary supplement to enhance productivity and welfare in semi-arid environments.