Effect of management system and season on semen freezability in Jakhrana bucks

AIM The objective of the study was to determine the effect of the management system (intensive and semi-intensive) and season (autumn and winter) on semen freezability in Jakhrana bucks. MATERIALS AND METHODS A total of 24 Jakhrana bucks of same body weight and age (BW=30 kg, age=1 year) were randomly allotted into two groups, viz., Group I (intensive system, 12 bucks) and Group II (semi-intensive system, 12 bucks). These two groups were statistically tested for their homogeneity with respect to age and BW. Semen was collected twice weekly using an artificial vagina during two seasons: autumn (September-November) and winter (December-February). A total of 240 semen samples (120 from each group and season) were evaluated for post-thaw motility (PTM), viability, abnormality, functional membrane integrity (hypo-osmotic swelling [HOS]) response and acrosomal integrity. RESULTS The mean values of PTM and acrosomal integrity of spermatozoa were significantly (p<0.01) higher in Group II as compared to Group I. The mean values of viability and abnormality were also differed significant (p<0.05) between groups. However, the mean values of HOS response were found non-significant (p>0.05) between groups. The season showed a significant effect on all parameters except viability and HOS response. The PTM and acrosomal integrity of spermatozoa were significantly (p<0.01) higher in winter as compared to autumn season. Abnormality of spermatozoa was significantly (p<0.05) lower in winter season. CONCLUSIONS This study indicates that both management system and season influence semen freezability. The semen collected from bucks reared under the semi-intensive system and winter season showed better semen freezability characteristics.