RESUMO
OBJECTIVE: We examined whether the vitrification method using P10 and PEPeS is suitable for the cryopreservation of two-cell stage embryos collected from multiple rat strains with the objective of strain preservation of inbred rat strains. RESULTS: The average numbers of two-cell stage embryos collected per female for F344/Jcl, ACI/N, BUF/N, and WKY/N strains were 7.0 to 12.0, and survival rates of the embryos after vitrification were 94.2 to 96.3 % The in vitro development rates of vitrified embryos transferred were 47.1 to 60.8 %. CONCLUSION: At least two offspring produced from the embryos collected from one female are required for strain preservation of inbred strain. Taken together, the results of the experiment indicated expected numbers of surviving fetuses for embryos collected from one female were 3.2 to 6.7, and all were usable for strain preservation. The results suggest that this vitrification method is suitable for strain preservation of multiple inbred rat strains.
