Induction of acrosome reaction in fresh and frozen-thawed bovine spermatozoa by platelet activating factor.

ABSTRACT

In vitro capacitation has been induced in fresh and frozen spermatozoa of Karan Swiss (KS) and Karan Fries (KF) crossbred cattle by using a phospholipid-platelet activating factor (1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine). The capacitation was monitored by examining acrosome reaction (AR) and motility at various levels of platelet activating factor (PAF) and at the end of each incubation time. On an average, with the increase in incubation time, there was a gradual decrease in motility and increase in acrosome reaction in both fresh as well as frozen spermatozoa. As PAF level increased, the motility of fresh sperms decreased and their acrosome reaction increased dramatically. However, in frozen-thawed semen, the motility remained almost the same and increase in AR of frozen spermatozoa was not pronounced. PAF level of about 100 microM was observed to be most optimum as at this level AR improved significantly without much loss of motility.