Nuclear transfer in cattle: Effect of linoleic acid-albumin on freezing sensitivity of enucleated oocytes

The effect of linoleic acid-albumin (LAA) supplementation to the media for IVM, enucleation, and activation on the developmental potential of bovine e mbryos produced by nuclear transfer (NT) into frozen-thawed cytoplasts was investigated. Blastomeres derived from morulae was placed in the perivitell ine space of frozen-thawed cytoplasts, which were then fused by a DC pulse. The proportion of fused embryos was similar between groups with and withou t LAA (87 vs. 90%). The proportion of development to blastocysts of NT embr yos derived from the media with LAA (14%) was higher than that without LAA (4%), indicating that LAA treatment of bovine oocytes during NM, enucleatio n and activation can improve the ability of such cytoplasts after freezing and thawing to develop into blastocysts after NT.