Successful production of offspring after superovulation and in vitro culture of embryos from domestic ferrets (Mustela putorius furos)

In an effort to expand the use of ferrets as models for genetic disease, se veral experimental parameters that are required for successful genetic mani pulation in this species were investigated. Optimum superovulation (19.3 +/ - 0.6 oocytes and embryos per female) was achieved after injections of 100 iu equine chorionic gonadotrophin (eCG) and 150 iu human chorionic gonadotr ophin (hCG). The ovulation rate achieved by the treatment was more than dou ble that induced by mating. Mating with a male immediately after hCG treatm ent did not significantly alter the number of oocytes ovulated or the numbe r of embryos present, indicating that mating is not required for superovula tion in ferrets. Of embryos harvested at the one-cell stage, 64.5% and 47.1 % developed into blastocysts when cultured in vitro in CZB or TCM-199 plus 10% fetal bovine serum (FBS) media, respectively. In contrast, only 17.1% o f embryos cultured in vitro in newborn calf serum NCSU-23 developed to the blastocyst stage. Both freshly retrieved and in vitro cultured embryos from cinnamon-coloured parents produced live young when transferred at the eigh t-cell stage into albino, pseudopregnant recipients. The percentage of kits delivered relative to embryos transferred was 61% for freshly retrieved em bryos and 32% for embryos cultured in vitro. These results demonstrate succ essful embryo transfer in ferrets and provide a basis for further study of genetic modelling approaches in this species after embryo manipulation.