Devising assisted reproductive technologies for wild-derived strains of mice: 37 strains from five subspecies of Mus musculus.
Authors: Mochida Keiji, Hasegawa Ayumi, Otaka Naoki, Hama Daiki, Furuya Takashi, Yamaguchi Masaki, Ichikawa Eri, Ijuin Maiko, Taguma Kyuichi, Hashimoto Michiko, Takashima Rika, Kadota Masayo, Hiraiwa Noriko, Mekada Kazuyuki, Yoshiki Atsushi, Ogura Atsuo
Journal: PloS one
Summary
# Editorial Summary: Assisted Reproductive Technologies for Wild-Derived Mouse Strains Wild-derived mouse strains represent genetically diverse models crucial for understanding evolutionary biology and disease mechanisms, yet their maintenance as living colonies has restricted their distribution and long-term preservation. Researchers at RIKEN BioResource Center developed assisted reproductive technology (ART) protocols for 37 wild-derived strains across five *Mus musculus* subspecies, optimising superovulation regimens, in vitro fertilisation, embryo cryopreservation, and embryo transfer procedures tailored to each strain's genetic background. Superovulation successfully yielded more than 15 oocytes per female in 34 of 37 strains; fresh and frozen-thawed spermatozoa achieved fertilisation rates of 79.0% and 54.6% respectively, whilst 94.6% of vitrified embryos survived cryopreservation and thawing. Notably, standard embryo transfer protocols worked in 25 strains, but the remaining 10 required modified protocols incorporating cyclosporin A immunosuppression and co-transfer with laboratory strain embryos to produce viable offspring. These advances enable safer, more efficient distribution of genetically valuable wild-derived strains for biomedical research without relying on live colony maintenance—a principle increasingly relevant to equine researchers seeking to preserve valuable genetic resources and facilitate collaborative research networks.
Read the full abstract on PubMed
Practical Takeaways
- •Not applicable to equine practice - this research concerns laboratory mouse genetics and reproductive technology development
- •No direct application to equine veterinary medicine, farriery, or equine-related disciplines
- •Findings may have peripheral relevance only to researchers studying fundamental reproductive biology principles
Key Findings
- •Superovulation was effective in 34/37 wild-derived mouse strains using either equine chorionic gonadotropin or anti-inhibin serum depending on genetic background
- •In vitro fertilization achieved mean success rates of 79.0% with fresh spermatozoa and 54.6% with frozen-thawed spermatozoa
- •Embryo cryopreservation by vitrification resulted in 94.6% survival rate with normal morphology restoration after warming
- •Successful embryo transfer was achieved in all 37 strains using either conventional protocol (25 strains) or modified protocol with cyclosporin A treatment (10 strains)