Fertility of Bull Semen with Added Amylase

Abstract

Alpha- or β-amylase was added to yolk-citrate-glycerol semen extender to determine effects on sperm motility and fertility. Motility trials revealed no harmful effect of either type of amylase at levels of 1 or 10 μg per ml during storage at 5 C for one week. Nor did β-amylase, at similar concentrations, depress motility during post-thawing storage at 5 C for three days. Consequently, 200 ejacula from 31 bulls were used to determine fertility of sperm with 0, 1, or 10 μg of α- or β-amylase per milliliter of semen extender. Other than addition of amylase, semen was processed, frozen (−195 C) and used according to routine procedures. The 60- to 90-day nonreturn percentages and numbers of first services (in parentheses) were 68.1 (4,294), 69.0 (3,807), 72.1 (4,770), 71.1 (4,684) and 70.7 (4,336) for control, 1 μg α-amylase, 10 μg α-amylase, 1 μg β-amylase, and 10 μg β-amylase, respectively. Average fertility for semen with amylase (70.7%) was significantly greater than that for controls (P ≃ 0.04). The high level of α-amylase resulted in higher fertility than the low level (P ≃ 0.06), but no such difference was apparent between the two levels of β-amylase. The results suggest that amylase may have affected sperm capacitation or that amylase may beneficially influence substrate availability for sperm metabolism. © 1968, American Dairy Science Association. All rights reserved.