97 BOER GOAT OFFSPRING BORN FOLLOWING TRANSFER OF CRYOPRESERVED EMBRYOS

Abstract

Cryopreservation of embryos is an important technique in the whole MOET program, which could help improve the transportation of genetic material across South Africa and globally. This trial evaluated the survival rate of goat embryos following transfer with cryopreserved Boer goat embryos. Twenty-seven multiparous Boer goat recipients were synchronized with CIDR for 16 days and injected with 300 IU of eCG at CIDR withdrawal. The recipients were allocated into 3 groups (n = 9). Group 1 received fresh embryos; Group 2 received slow frozen embryos; and Group 3 received vitrified embryos. Expanded blastocysts used were surgically collected from donors superovulated with pFSH on 7 following AI. Two blastocysts were transferred laparoscopically to the uterine horn ipsilateral to functional CL. A pregnancy rate of 85.7% (6) was obtained following the transfer of fresh embryos and tended to be better than in the does receiving slow frozen and vitrified embryos, (n = 4; 50.0% and n = 3; 37.5% does pregnant, respectively) with no significant differences. The kidding rate of the recipient does declined to 57.0% (4) and 25.0% (2) for fresh and slow frozen groups, respectively. The embryo survival rate of 35.7% (n = 5) for fresh, 25.0% (n = 4) for conventional slow freezing and 31.3% (n = 5) for vitrification was obtained and was not affected by the number of CL present on the respective ovaries at the time of embryo transfer. Although the pregnancy rate following the transfer of fresh embryos was satisfactory, the embryo survival rate following the transfer of fresh or cryopreserved embryos tended to be lower.

The authors acknowledge the University of the Free State for financial and facility support and National Research Foundation (Thuthuka) for financial support for conducting this trial.