Comparative Serum Enzyme and Hormone Profiles in Intact Versus Castrated West African Dwarf Sheep in Kwara State, North Central Nigeria

Castration is widely practised in male sheep destined for fattening in Nigeria, yet its long-term biochemical and endocrine consequences under local management conditions have not been analytically compared with intact rams in a controlled study. This study compared serum enzyme activities and hormone profiles in intact and castrated West African Dwarf sheep managed under identical smallholder conditions in Kwara State, North Central Nigeria. Sixty male sheep comprising thirty intact rams and thirty surgically castrated wethers aged twelve to eighteen months were enrolled. Serum testosterone, oestradiol, cortisol, growth hormone, insulin-like growth factor-1, alanine aminotransferase, alkaline phosphatase, creatinine kinase, and lactate dehydrogenase were measured on a monthly basis for five consecutive months. Testosterone was undetectable in all castrated animals while intact rams maintained physiologically appropriate levels. Serum oestradiol was significantly lower in wethers than intact rams. Cortisol was paradoxically lower in castrated animals, potentially reflecting reduced social stress from dominance interactions. Insulin-like growth factor-1 was not significantly different between groups, suggesting comparable somatotrophic axis activity. Creatinine kinase and lactate dehydrogenase were modestly lower in wethers, consistent with reduced physical activity. These comparative analytical data provide an empirical endocrine and enzymatic basis for understanding the physiological effects of castration in West African Dwarf sheep and have implications for fattening management protocols in North Central Nigeria. Keywords: castration, testosterone, serum enzymes, growth hormone, West African Dwarf sheep.