Zinc supplementation promotes oocyte maturation and subsequent embryonic development in sheep.

Zinc plays a crucial role in the growth and reproductive functions of animals. Despite the positive effects of zinc that have been reported in oocytes of cows, pigs, yaks, and other animals, the influence of zinc on sheep is little known. To investigate the effect of zinc on the in vitro maturation of sheep oocytes and subsequent parthenogenesis-activated embryonic development, we added different concentrations of zinc sulfate to the in vitro maturation (IVM) culture medium. The IVM culture medium with zinc improved the maturation of sheep oocytes and the subsequent blastocyst rate after parthenogenesis activation. Notably, it also enhanced the level of glutathione and mitochondrial activity while reducing levels of reactive oxygen species. Thus, zinc addition to the IVM medium improved the quality of oocytes with a positive effect on the subsequent development of oocytes and embryos.