In vitro development of goat (Capra hircus) embryos following cysteamine supplementation of the in vitro maturation and in vitro culture media

The present study was designed to investigate whether cysteamine supplementation in the in vitro maturation (IVM) or culture (IVC) media, or a combination of both could improve the yield of in vitro goat blastocyst production. Goat oocytes were aspirated from slaughterhouse derived ovaries and matured in vitro. Semen was collected from a healthy fertile buck, capacitated and the in vitro matured oocytes were fertilized using capacitated spermatozoa. The putative zygotes were then cultured in IVC medium. The IVM and IVC media were supplemented with 0, 50, 100, 200 or 400 M of cysteamine. A significant (p < 0.05) increase in the cleavage rate and blastocyst yield was recorded when the IVM medium was supplemented with 100 M cysteamine. A too high concentration (400 M) significantly (p < 0.05) decreased the cleavage rate and blastocyst yield. Supplementation of the IVC medium with 200 M cysteamine significantly increased the cleavage rate and blastocyst yield, while the other concentrations (50, 100 and 400 M) had no effect. Ultimately cleavage and blastocyst yield was increased after cysteamine supplementation with 100 M in the IVM medium and 200 M in the IVC medium. No significant difference was recorded regarding hatching rate (HR) and the total cell numbers of blastocysts produced between control and different cysteamine treatment groups. In conclusion, it can be said that the cleavage rate and blastocyst yield can be successfully increased by cysteamine supplementation in IVM medium or IVC medium, or both IVM and IVC media without compromising the quality of the zygote.