effects of essential and non-essential amino acids on in-vitro maturation, fertilization and development of immature bovine oocytes

background: addition of amino acids to the culture medium is beneficial for embryonic development in many species. objective: the objective of this study was to investigate the effects of amino acids on the in vitro maturation and embryonic development of the bovine oocyte. materials and methods: bovine ovaries were collected from a local abattoir and brought into laboratory. cumulus-oocyte complexes (cocs; n=1212) were aspirated from follicles (2-8 mm in diameter) and randomly assigned to four groups for maturation in culture: (1) basic medium alone as control; (2) basic medium supplemented with 2% mem essential amino acids solution; (3) basic medium supplemented with 1% mem non-essential amino acids solution; and (4) basic medium supplemented with 2% mem essential amino acids solution + 1% mem non-essential amino acids solution. cocs were incubated in 1 ml maturation medium in an organ culture dish at 38.5�c in an atmosphere of 5% co2 with high humidity. after 24 h of culture, 372 oocytes were fixed to determine maturation rate and the remaining oocytes were used for in vitro fertilization (ivf). following 18 h of insemination, 437 oocytes were fixed and examined for fertilization and 403 oocytes were further cultured. results: there were no differences in maturation rates and penetration rates among the four groups. although oocyte cleavage rates were not different in the four groups, embryo development up to the 8-cell stage and blastocyst were significantly higher (p<0.05) in group (2) and (4) than in the control and group (3). conclusion: these results indicate that the presence of amino acids, especially essential amino acids in the maturation medium is beneficial to oocyte cytoplasmic maturation and subsequent early embryo development in vitro.