Highlights on biological role of superoxide dismutase activity in buffalo and stallion seminal plasma

Abstract EN

Significant activities of superoxide dismutase (SOD) were identified in seminal plasma of 10 buffalo bulls (7.24 ± 1.26 Units/ml) and 10 Arabian stallions (8.33 ± 1.23 Units/ml).Despite there were significant (P<0.05) bull-to-bull and stallion-to-stallion variations in SOD activities, neither the species of animals nor the age of bulls or stallions had any significant effect.

When buffalo (n=100) and stallion (n=80) ejaculates were classified on the basis of SOD activities, it was found that samples containing high activities (>16 Units/ml) of the enzyme, were characterized by a significant (P<0.05) reduction in semen volume,number of motile sperm per ml and in the percentage of morph-ologically normal sperm.Likewise,freeze per thaw processing of buffalo ejaculates containing the highest mean activity of SOD (30.21 ± 3.77 Units/ml) resulted in a significant (P<0.05) decrease in post thaw sperm viability.

Also, retrospective assessment of stallions fertility revealed that augmentation of SOD activity (up to 17.38 ± 3.82 Units/ ml) in seminal plasma was associated with a significant (P<0.05) increment in the number of matings required per each stallion to achieve a pregnancy.

In conclusion, quantification of SOD activity in seminal plasma seems to be a reliable predictor for: 1- The quality of freshly ejaculated buffalo and stallion semen; 2- The freezability of buffalo semen; and 3- The fertility potential of breeding stallions.