THE EFFECT OF SEVERAL ASCORBIC ACID CONCENTRATIONS ON SWINE OOCYTE MATURATION AND EMBRYO CULTURE

Considering that free radicals are easily formed both in vivo and in vitro and that swine oocytes and embryos have a high content of unsaturated and therefore highly oxidizable fatty acids antioxidants must be added to the culture media. Ascorbic acid has been shown to improve swine oocyte maturation and the development of bovine and swine embryos. The goal of this study was to establish the influence of several ascorbic acid and a-tocopherol concentrations on swine oocyte maturation in order to improve oocyte maturation media. Pig oocytes were cultured for 44 hours at 37°C in 5% CO2 atmosphere, in M199 containing several ascorbic acid (50, 150, 250, 500 and 750 jM) concentrations. Oocytes were fertilized and the embryos were cultured for another 94 hours in TALP medium containing the same antioxidant concentrations. The addition of 50, 150, 500 and 750 mM ascorbic acid to the maturation medium lead to an increase in the number of oocytes assessed as 3 and 4 and a decrease in the number assessed with 0. The number of embryos that developed in medium supplemented with 50 jjM ascorbic acid was significantly higher than the contro, thus proving the beneficial influence of ascorbic acid on embryo development