Abstract
The effects of alteration of metabolic substrates and supplementation of amino acids on in vitro development of bovine embryos were examined. One-cell embryos derived from in vitro fertilization were cultured using a semi-chemically defined medium, Brinster's Medium, containing 3 mg/ml bovine serum albumin (BMOC-3) as a basal medium. BMOC-3 did not support embryonic development to the morula stage, but blastocysts were obtained by omitting glucose and lowering the lactate level from 20.12 to 3.0 mM and the pyruvate level from 0.5 to 0.3 mM (mBMOC-3). Supplementation of amino acids (glutamine plus the other 12 essential amino acids, as well as further addition of 7 non-essential amino acids) improved the embryonic developmental rate to the blastocyst stage with an increase in cell number equal to that for co-cultured embryos with bovine oviductal cells in TCM 199 with 10% fetal calf serum. These results clarified that the one-cell bovine embryo can develop to the blastocyst stage in a semi-chemically defined medium, and that amino acids support embryonic development in vitro.
