CULTURING 2-CELL TO 8-CELL CAPRINE EMBRYOS USING DOMESTIC CHICKEN EGGS

Early‐stage caprine embryos were placed in the chick embryo amnion to determine if this culture method would support the development of embryos from a farm animal species. Following superovulation and natural mating, two‐ to eight‐cell embryos were surgically collected from crossbred donor goats. Embryos were allotted to in vitro culture treatments across two different experiments (EXP). In EXP‐I, embryos allotted to Treatment A (control) were cultured in Ham's F‐10 with 10% fetal calf serum and 1% antibiotic‐antimycotic (HF‐10). Embryos in Treatment B were placed on a bovine fetal uterine fibroblast monolayer in HF‐10, embryos allotted to Treatment C were agarose embedded and injected into the amniotic cavity of a day‐4 chick embryo and those placed in Treatment D were co‐cultured in HF‐10 with day‐15 caprine trophoblastic vesicles. In EXP II Treatments A, B, and C were the same; however Treatment D was omitted. EXP‐I and EXP‐II also differed in that chick embryo co‐culture was for 72 hr in EXP‐I but was extended to 96 hours in EXP‐II. Additionally, the monolayer co‐culture was limited to 96 hr in EXP‐II; whereas, embryos in EXP‐I remained on monolayer culture for 96 hr plus an additional 72 hr for subsequent embryo evaluation. Results indicate that the amniotic cavity of the developing chick embryo enhanced the development of two‐ to eight‐cell caprine embryos through to hatching blastocysts when compared with that of the control medium alone. In addition, the beneficial effects of monolayer co‐culture appeared to be lost when the caprine embryos were removed from the monolayer, whereas, the in vitro viability of these embryos cultured in the chick embryo amnion was maintained after removal from the amniotic cavity. Copyright © 1990 Wiley‐Liss, Inc.