INVITRO COCULTURE OF EARLY STAGE CAPRINE EMBRYOS WITH OVIDUCT AND UTERINE EPITHELIAL-CELLS

Early stage caprine embryos were incubated with goat oviduct and uterine cells to evaluate whether these cells could be used as a somatic cell culture system to enhance development through the developmental block at the 8- to 16-cell stage during in-vitro culture. Following gonadotrophin treatment and natural mating, 2- to 4-cell embryos were surgically recovered from donor females for in-vitro culture studies. In Experiment 1, embryos were equally and randomly allotted to culture treatments of either culture medium plus caprine oviduct cells or culture medium alone. In both treatment groups, embryos were incubated in Medium-199 with 10% fetal bovine serum, 0.25% lactalbumin and 1% antibiotic-antimycotic at 37-degrees-C in a humidified atmosphere of 5% CO2 in air. In Experiment 2, similar embryos were cultured in the same medium with either caprine oviduct cells, caprine uterine cells or sequentially incubated with oviduct cells and then uterine celts during a corresponding incubation interval. The culture conditions in Experiment 2 were the same as in Experiment 1. Following 72 h in culture, (Experiment 1), significantly more embryos developed through the in-vitro developmental block into blastocysts and hatched blastocysts when cultured with oviduct cells compared with no embryos developing through the in-vitro block when incubated with medium alone. In Experiment 2, caprine embryos co-cultured with oviduct cells alone resulted in more embryos developing into blastocysts and hatched blastocysts compared with those co-cultured with uterine cells alone. Unexpectedly, when embryos were sequentially co-cultured on oviduct cells and then on uterine cells, fewer developed to blastocysts and hatched blastocysts in vitro compared with embryos that were co-cultured on oviduct cells alone; however, the means were not significantly different. These results clearly indicate that epithelial cells from the reproductive tract of the goat provide an effective co-culture system for in-vitro development of caprine embryos through the in-vitro developmental block.