Comparative study of functional and biochemical parameters in frozen bovine sperm.

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