Effects of vitamin B(12) supplementation on the quality of Ovine spermatozoa

The present study was undertaken to investigate the effect of various levels of vitamin B(12) in Tris extender on semen quality of Dallagh rams following the cooling and freeze/thawing process. Semen was collected from six healthy and mature rams with an average body weight of 60.0 ± 5.0 Kg using an electro ejaculator. High quality samples were mixed and diluted in Tris extender supplemented with different concentrations of vitamin B(12) (0, 1, 2 and 3 mg/ml). The semen aliquots were cooled and preserved at 5°C and their qualities were evaluated during pre-freezing and then the cooled semen samples were packaged into 0.25 ml straws. Straws were frozen in the vapor of liquid nitrogen, and were then stored at -196ºC. Straws were thawed seven days later and the characteristics of spermatozoa were examined. Results of this study showed that the effect of vitamin B(12) on characteristics such as viability, motility, progressive motility and normality of spermatozoa were significant in pre and post freezing conditions (P<0.05). In conclusion, for long term storage of semen of Dallagh rams, we recommend using 2 mg/ml of vitamin B(12) in semen extender.