effect of vitamins c or e supplementation to tris diluent on the semen quality of awassi rams preserved at 5 ˚c

the present study was aimed to test the efficacy of adding vitamins c or e to tris-fructose-egg yolk diluent to increase awassi ram sperm storage period at 5 ˚c. semen samples from six mature awassi rams were used in this study. the semen samples were diluted by tris-glucose-egg yolk. diluted semen sample was divided into three parts. the first part was added with 0.9 mg ml-1 vitamin c, the second part was added with 1 mg ml-1 vitamin e and the third part was considered as a control without any addition. the diluted semen samples were cooled gradually and preserved at 5 ˚c for five days. sperms in cooled diluted semen samples were examined for motility, vitality, abnormalities and acrosomal defects every 24 hr for five days. results of the present study showed an increase in the viability of spermatozoa diluted in the tris diluent containing vitamins c or e stored at 5 ˚c for 120 hr compared with the control group. there were significant (p < 0.05) effects of vitamins c and e addition to semen diluents on sperm motility as well as the sperm viability in different times of preservation at 5 ˚c. significant (p < 0.05) higher sperm abnormalities and acrosomal defects values (37.6 ± 1.3% and 71.5 ± 1.1%, respectively) were found after 120 hr incubation in tris free vitamin c (control) at 5 ˚c compared with those of containing vitamin c (18.8 ± 1.8% and 52.8 ± 4.3%, respectively). from the results of the present study, it could be concluded, that the addition of antioxidants such as vitamins c and vitamin e to semen preservation media could improve longevity and quality of cooled sperm in awassi ram semen.