The Antioxidant Effect of Root Bark of Enalai (Zizyphus Oxyphylla) Extract on the Improvement of Bull Semen Quality

Abstract

Zizyphus oxyphylla is locally called Enalai in Pasthu language. Methanolic extracts of Zizyphus oxyphylla (MEZO) root bark possesses antioxidant potential. As reactive oxygen species generate during collection of semen and cryopreservation by thermal and cold shock, causing oxidative stress and thus affecting the quality of semen. The objective of this study was to evaluate the antioxidant effect of MEZO on the improvement of bull semen quality. The research was conducted on Friesian bull semen, collected by artificial vagina at Semen Production Unit (SPU), Harichand, district Charsada, Khyber Pakhtunkhwa, Pakistan. Various inclusions groups (0.5mL, 1mL, 1.5mL, 2mL, 2.5mL and control) of MEZO and semen were extended in egg yolk extenders. Semen quality parameters (spermatozoa motility, spermatozoa viability, spermatozoa acrosomal integrity and spermatozoa plasma membrane integrity) were checked from post-thawed spermatozoa. The semen quality parameters were enhanced significantly (p < 0.05) in extended semen containing 0.5 mL extract (mean spermatozoa motility; 68.25, viability; 67.79, acrosomal integrity; 72.17 and plasma membrane integrity; 67.12) compared to control group (the mean spermatozoa motility; 49.21, viability; 50.79, acrosomal integrity; 58.67 and plasma membrane integrity; 50.87) respectively. The extended semen containing 1mL extract were found to be significantly higher in above mentioned parameters compered to control group, however, it was decreased compared to semen containing 0.5 mL extract. This decline in semen quality parameters was continued in all inclusions above 0.5mL dose dependently. Therefore it can be concluded that Enalai extract (MEZO) in extended semen showed significant antioxidant response that leaded to improve spermatozoa motility, viability, acrosomal integrity and plasma membrane integrity.

Keywords:  Zizyphus oxyphylla, antioxidants, Friesian bull semen, oxidative stress.