Antioxidant treatment during preservation of bovine ovaries increased the development potential of embryos.

The overnight preservation of bovine ovaries would be highly useful in the subsequent harvest of viable oocytes for reproductive study. The present study aimed to optimize conditions for overnight preservation of bovine ovaries by examining the effects of temperature, solution and supplementation. In Experiment 1, the rate of development to the blastocyst stage of oocytes derived from ovaries preserved at 15°C was higher than that at either 5 or 25°C (p < 0.05). In Experiment 2, the rate of development to the blastocyst stage of oocytes derived from ovaries preserved in University of Wisconsin solution was higher than when PBS or saline was used (p < 0.05). In Experiment 3, oocytes preserved in saline supplemented with 0.3 mM glutathione (GSH) exhibited an increase in the rate of blastocyst formation compared with oocytes supplemented with 0 or 3 mM GSH (p < 0.05). In Experiment 4, supplementation with 10 µM epigallocatechin gallate during ovary preservation increased the rate of blastocyst formation (p < 0.05). The blastocysts derived from ovaries stored in saline supplemented with GSH at 15°C for 24 h were shown to develop into normal offsprings following transfer to recipient heifers. Our studies indicate that bovine IVM/IVF embryos derived from ovaries preserved in saline supplemented with an antioxidant at 15°C for 24 h can successfully develop to the blastocyst stage and result in offspring.