Effects of Nu-Serum® on in vitro development of goat (Capra hircus) embryos

To evaluate the effects of a commercially produced serum substitute on the in vitro development of caprine embryos, registered Nubian doelings were synchronized with norgestomet-impregnated implants (Synchromate-B®: CEVA) and superovulated with descending doses of FSH-p® (Schering). A total of 246 embryos was collected and placed in Tissue Culture Medium 199 (TCM 199, Gibco Laboratories) containing Nu-Serum® (NuS) at concentrations of 2.5%, 5.0%, 10%, or 20%. Control treatments consisted of TCM 199 alone or TCM 199 plus 10% heat-inactivated fetal bovine serum (FBS). Embryos developed in all concentrations of NuS to the morula, blastocyst, and expanded blastocyst stages. The TCM 199 plus 10% NuS had significantly higher percentages of embryos developing to the expanded blastocyst stage than TCM 199 plus 10% FBS. Time to expanded blastocyst development in NuS was shorter than in the TCM 199 plus FBS. No stage-specific block to development was observed with embryos collected and cultured in vitro for any of the treatments. These results demonstrate that NuS, when compared to FBS, allowed a higher percentage (P < 0.05) of caprine embryos to develop to the expanded blastocyst stage, thus providing a valuable substitute for FBS.