Species-specific features of culturing and vitrification of bovine and rabbits embryos

In animal breeding, reproductive biotechnologies such as vitrification and embryo culturing are essential. To find species-specific characteristics of embryo cultivation and vitrification, we studied embryos from cattle and rabbits. Bovine IVP embryos were cultivated in mSOF with freshly made base and on the basis of mother liquor without sodium bicarbonate stored for 1 year at 4°C, while rabbit embryos were cultivated in a CO₂ incubator at 38.5°C, 7% CO₂, using TCM 199 and DMEM F12 media. Using two protocols that varied in exposure modes and base solution composition (1) DPBS + 0.2% BSA and 2) TLP-HEPES + 20% blood serum (TH20)), we conducted investigations on the vitrification of rabbit embryos and bovine zona-free IVP embryos in triacetate hollow fiber. Only 44.5% of rabbit embryos produced in THM 199 continued to develop over the course of 120 hours, compared to 68% of embryos cultured in DMEM F12. After 93 bovine embryos were cultured in mSOF medium with the base preserved for 1 year, 25 embryos released from the pellucid zone, while when 172 embryos were cultivated in mSOF with a freshly created base, 60 of them released from the pellucid zone. The survival rate of rabbit embryos after vitrification and warming procedures was, for protocol #1, morulae in vitro, 53%, and morulae in vivo, 47.8%; for protocol #2, morulae in vitro, 84.6%, and morulae in vivo, 68.0%. Reducing the sucrose concentration in the warming solution to 0.5M and in the dilution solution to 0.25M resulted in a 93.8% improvement in the survival rate of bovine embryos. Therefore, research into species-specific reproductive biotechnologies improves the effectiveness of their use in animal husbandry.