Effect of dietary onion (Allium cepa L.) powder as an antioxidant on semen quality, blood biochemicals, and reproductive parameters, as well as immunological variables of rabbit bucks under severe heat stress.

This study aimed to evaluate the antioxidant effects of onion (Allium cepa L.) powder on the immunological variables, redox state, and semen quality of rabbit bucks exposed to severe heat stress. Thirty-six mature bucks (7 months old) were divided into three groups consisting of 12 bucks each, namely group I, control; group II, 400 mg onion powder/kg diet; and group III, 800 mg onion powder/kg diet.