Ameliorating effect of vitamin E on in vitro development of preimplantation buffalo embryos

Oxidative stress has been implicated in the etiology of defective embryo development. Vitamin E is an effective lipid-soluble antioxidant, protecting cell membranes from peroxidative damage. In this context, this study was undertaken to find if supplementation of vitamin E in culture medium could ameliorate the developmental competence of preimplantation buffalo embryos. Vitamin E was supplemented in maturation/embryo culture medium at concentrations of 0, 50, 100, 200 and 400 mu M. The developmental competence of buffalo embryos was assessed by observing the cleavage, morulae, blastocyst rate, total cell count and comet assay. Vitamin E had no significant effect in maturation medium. Vitamin E in embryo culture medium under 5% O-2 significantly reduced blastocyst formation in the 400 mu M supplemented group. Culture under 20% O-2 enhanced the frequency of blastocyst formation, total cell count and significantly reduced comet tail in the 100 mu M supplemented group (P < 0.001) when compared with the control. Vitamin E in ECM for the first 72 h of culture period enhanced blastocyst rate and total cell number in the 100 mu M group (P < 0.001) when compared with the control. Our results demonstrate that the addition of Vitamin E may enhance the developmental competence of buffalo embryos in vitro by protecting them from oxidative stress.