The Effect of Amylase, Catalase, and a Decapacitating Preparation on Fertility of Bull Semen Diluted in Ambient Temperature Extender

Abstract

Four ejaculates from each of three bulls were diluted in four ambient temperature extenders: (1) Caprogen; (2) Caprogen containing 8 fl-gfml ",·amylase; (3) Caprogen containing 4·5 fl-gfml catalase; and (4) Caprogen containing amylase and catalase. The conception rate (49·day % non-return rate) for each extender was 64·63; 63·37; 64·58; and 66·09% respectively. Whereas the addition of catalase significantly increased conception rates (P = 0·025), the addition of amylase did not (P > 0·25). There was a significant enzyme interaction, suggesting that any beneficial effect attributable to the amylolytic preparation was only exerted in the presence of catalase (P < 0·025). The significant improvement in in vitro livability at 37°C by the addition of amylase in the absence of catalase was minor compared to the improvement in livability obtained by the addition of catalase