EFFECT OF AMINO-ACID SUPPLEMENTATION IN CULTURE MEDIA ON DEVELOPMENT OF BOVINE OOCYTES MATURED AND FERTILIZED IN-VITRO

The effect of supplementing modified synthetic oviductal fluid (m-SOF) with essential and non-essential amino acids on the in vitro developm ent of one-cell bovine embryos, was assessed. After in vitro fertiliza tion, oocytes were randomly allocated to 4 treatment groups using a 2 x 2 factorial design : (1) control : m-SOF medium with BSA, glucose, p yruvate, lactate and glutamine; (2) control medium + non-essential ami no acids (NEAA); (3) control medium + EAA's; (4) control medium + EAA' s + NEAA. The mean oocyte cleavage rates among treatments were statist ically nonsignificant and ranged from 80.2 to 82.5%. Addition of EAA's increased the proportion of cleaved embryos developing beyond the 16- cell stage. However, only when both NEAA and EAA's were present, a sig nificant increase in development to the blastocyst stage was observed compared to control medium (33.0 +/- 4.0 vs 10.7 +/- 3.0, respectively ). This experiment demonstrates that both EAA's and NEAA are required to increase the frequency of blastocyst formation in vitro.