Acrosin activity of canine spermatozoa as an index of cellular damage

Eight experiments were performed to validate an extraction technique for canine acrosin and to quantitate the acrosin activity of fresh and frozen-thawed spermatozoa. Acrosin activity from fresh spermatozoa differed amongst dogs and was influenced by the interval since previous ejaculation. Freezing and thawing spermatozoa induced a loss of acrosin activity that differed with the extender in which the spermatozoa were frozen. The assay of acrosin activity, in conjunction with motility estimates, provides a more complete evaluation of the efficacy of seminal extenders in attenuating freezing injury than do motility estimates alone.