Effect of capacitating agents on sperm pretreatment during in vitro fertilization for blastocyst production in caprines

The present study aimed at comparing the relative efficacy of different capacitating agents used for sperm pretreatment during in vitro fertilization (IVF) and subsequent embryo development of caprine oocytes. In experiment 1, the effect of different concentrations of heparin (0, 20, and 50 mu g/mL) on sperm pretreatment for different periods of time (30 and 60 min) was studied. In experiment 2, the dose-dependent effect of calcium ionophore (0, 0.1, 0.2, and 0.5 mu M) on sperm pretreatment was assessed. Experiment 3 validated and compared the effects of both capacitating agents on sperm pretreatment for capacitation based on the results of the first two experiments. The treated sperms from each group were used for in vitro fertilization and subsequent embryo development. The results indicated that in experiment 1, capacitation with heparin at 20 mu g/mL for 60 min had significantly higher (P < 0.05) cleavage and blastocyst production. In experiment 2, capacitation with calcium ionophore at 0.1 mu M had significantly more morulae (P < 0.05) and numerically more blastocyst production. In experiment 3, capacitation with heparin at 20 mu g/mL had a significantly higher (P < 0.05) blastocyst production rate as compared to calcium ionophore treatment. Based on this study, heparin can be used to enhance capacitation of freshly collected sperms during in vitro fertilization and subsequent embryo development.