Study the effect of seasonal months on buck semen using modified Tris solution for sperm motility following cryostorage

Abstract

Abstract :To investigate the effect of months on some characteristics of semen and the effect of cryostorage for several days on individual sperm motility of the semen treated with modified Tris solution, this study was conducted.The research was done in the farm and the laboratory of Department of Surgery and Obstetrics -College of Veterinary Medicine –University of Baghdad. Eight mature indigenous bucks aged 2-3 years old, were used for 6 months from 1-10-2005 to 31-3-2006. Semen was collected once a week from each male using artificial vagina. The study was included two experiments. Experiment No.1: study the effect of seasonal months on some characteristics of semen(ejaculate volume, seminal Hydrogen ions concentration {pH}, color ,mass and individual motility ,sperm concentration X 109/ml, vitality and dead sperm percentage and morphologically abnormal sperm. Experiment No.2 study the efficiency of modified Tris solution (MTS) (Tris 3.03gm+fructose 1.25gm+ citric acid 1.67gm+egg yolk) on individual sperm motility that collected from studied buck in experiment No1 and preserved in the refrigerator at 4-5°C.There was a significant (P<0.05) positive effect of October month on some semen characteristics (volume,pH , mass motility, individual motility, and lower percentage of dead and morphologically abnormal sperms, ) of bucks compared with other months . The results showed no significant (P>0.05) changes in sperm motility after 24 to 72 hrs of cryostorage. However there was a significant (p<0.05) decrease in percentage of individual motility after 96 hrs of cryostorage. It is concluded that October was more effective month on improving certain semen characters than other months in addition; cryostorage with MTS was suitable to preserve semen of local bucks in the refrigerator at 4-5 °C for 72 hours.