COMPARATIVE-STUDY OF FUNCTIONAL AND BIOCHEMICAL PARAMETERS IN FROZEN BOVINE SPERM

In order to correlate functional and biochemical parameters, frozen bo vine sperm samples presenting diverse motility were studied. Specimens collected from four bulls (A, B, C and D) were graded according to mo tile spermatozoa percentage and vigour, regarding the sample from bull A as highest motility, those from bulls B and C of intermediate motil ity and that from bull D of low motility. In order to evaluate lipid p eroxidation enhanced by the addition of sodium ascorbate and ferrous s ulphate, thiobarbituric acid reactive substances (TEARS) were measured . Values were 0.34+/-0.18 and 4.95+/-0.31 nmol TEARS/10(8) spermatozoa for samples A and D, respectively. Superoxide dismutase (SOD) activit y was 144+/-16.48 and 44+/-4.0 IU/10(10) spermatozoa for A and D, resp ectively, while intermediate values were recorded for samples B and C. The capability to undergo acrosome reaction induced by calcium ionoph ore A23187 was significantly lower for sample D, but differences were negligible for the remaining three samples inter se. Motile spermatozo a percentage correlated closely both with SOD activity (r=0.92) and wi th TEARS production (r=-0.80), but not with acrosome reacted percentag e (r=0.65). From correlation data, it would be inferred that motility is not entirely indicative of sperm quality.