Effect of the addition of insulin like growth factor-I (IGF-I) on cryopreservation of Hariana bull semen.

This experiment was designed to study the effect of insulin like growth factor-I (IGF-I) on cryopreservation of Hariana bull semen. For this purpose, semen ejaculates were collected from four Hariana bulls using artificial vagina at biweekly interval. The semen samples which possess more than 70% initial progressive motility and above 500 million/mL spermatozoa concentration was subsequently subjected to processing for experiment. Semen samples were extended in egg yolk tris glycerol (EYTG) extender and split into four groups. IGF-I was added at 50 ng/80 × 106 spermatozoa, 100 ng/80 × 106 spermatozoa and 150 ng/80 × 106 spermatozoa in the group II, III, IV respectively and group I as control (without IGF-I). Semen samples were evaluated at pre-freeze and post-thaw stage for percent individual progressive motility, percent live spermatozoa, percent hypo-osmotic swelling (HOS) positive spermatozoa, percent spermatozoa with intact acrosome. A significant (p < 0.05) higher individual progressive motility, viability, HOS response and acrosomal integrity was observed at pre-freeze and post-thaw stage by using 150 ng/ml IGF-I. Concentration of 150 ng/mL IGF-I was found to be more beneficial in cryopreservation of Hariana bull spermatozoa as evidenced by post-thaw seminal parameter. It was concluded that IGF-I can be added to extender for improving cryosurvial of Hariana bull spermatozoa.