TERM DEVELOPMENT OF CAPRINE EMBRYOS DERIVED FROM IMMATURE OOCYTES IN-VITRO

Ovaries were surgically removed from female goats (Toggenburg, Nubian and Saanen breeds). Oocytes were collected by follicular aspiration or after ovaries were minced, then matured in mTCM-199 with 100 mu g LH + 0.5 mu g FSH + 1.0 mu g estradiol 17-beta/ml for 27 h prior to in vi tro fertilization (17). Although more oocytes were made available by m incing than by aspiration, higher proportions of aspirated oocytes wer e fertilized and developed to morulae. Proportions that fertilized and reached morulae were 82/102 (80.4%) and 50/102 (49.0%) versus 77/126 (61.1%) and 27/126 (21.4%) for oocytes obtained by aspiration and afte r ovarian mincing, respectively (P<0.05). Proportions of inseminated o va undergoing cleavage and continuing development to the morula stage differed significantly (P<0.05) among 5 co-culture treatment groups, w ith higher proportions of cleavage (23/27, 85.2%) and morulae (14/27, 51.9%) obtained by co-culture on caprine cumulus cells (cCC). Some ooc ytes reached the blastocyst stage (4/54, 7.4%) following oocyte collec tion by aspiration and culture on caprine oviduct epithelial cells (cO EC). After 4- and 8-cell stage embryos obtained by aspiration and cult ure on cCC were transferred pregnancy resulted. Twin male kids (develo ped from different embryos) were born on August 6, 1993, and have deve loped into normal bucks. Conditions reported here provided an adequate environment for support of oocyte maturation, fertilization and early embryonic development in vitro (IVMFC) with normal development after embryo transfer.