Effect of buffalo bull breeds on developmental competence and vitrification of in-vitro produced embryos

Objective: To assess effect of buffalo bull breed on the development and cryotolerence of the in vitro produced embryos. Methods: Three types of frozen semen were adopted; Egyptian, Italian and cross-bred (Egyptian-Italian) breeds were used for in-vitro fertilization and vitrification of their embryos. Oocytes were collected from buffalo ovaries and matured in vitro for 24 h, then they were fertilized using the three semen breeds. The produced embryos of morula and blastocysts were vitrified using ethylene glycol and dimethyl sulfoxide then evaluated for their viability after warming. Results: The cleavage and blastocysts rates significantly declined in oocytes fertilized by Egyptian (P<0.01) than in Italian (P<0.05) and crossbred (P<0.05) frozen semen. After embryo vitrification, there were no significant differences among the three breeds in the percentages of morphologically viable embryos evaluated directly after warming and at 24 h post-culture. Conclusions: The in vitro fertilization response to frozen-thawed semen varies between breeds; however, the resistance of produced embryos to the damage effect of vitrification does not vary