The Role of Reproductive Technologies and Cryopreservation of Genetic Materials in the Conservation of Animal Genetic Resources, A Review

The conservation of animal genetic resources guarantees the continual existence of diversified nature and thereby ensures the achievement of valuable economic, ecological, social, and cultural demands. Animal genetic resources can be conserved in their natural environments (in-situ conservation) and outside their natural habitats (ex-situ conservation) through different techniques such as zoo, captive breeding, aquarium, and in gene banks by collecting and preserving their germplasm. Reproductive technologies and cryopreservation of genetic materials play a pivotal role in preserving genetic diversity, supporting breeding programs, contributing to biodiversity conservation, adapting to changing environments, and fostering advancements in agriculture and animal husbandry. Its importance extends to ensuring food security, resilience in the face of climate change, and economic opportunities for communities. The collection and cryopreservation of genetic materials, including sperm, oocytes, embryos, and other biological materials capable of generating new offspring, have critical importance in supporting in-situ conservation efforts of threatened animals and the rehabilitation of extinct species and breeds. Advancements in reproductive technologies such as artificial insemination, in-vitro fertilization, embryo transfer, and nuclear transfer have greatly promoted efficiencies in animal reproduction and serve as a significant tool for domestic and wildlife animal conservation, particularly those threatened with extinction. Cryopreservation of germplasm and the application of reproductive technologies possess great success in breeding improvements and genetic resource conservation strategies, increasing the possibility of population rehabilitation. Good achievements have been observed in reconstituting animal populations in different parts of the world, while successful attempts have also been recorded in recovering extinct animals from cryopreserved genetic materials. In Ethiopia, reproductive technologies, such as cryopreservation and artificial insemination, are limited to the collection and distribution of bovine semen for genetic improvement and/or restocking activity. However, other reproductive technologies, including in vitro fertilization, ovulation induction, and reproductive surgeries, are not yet fully implemented due to various limitations. Initiative efforts are started in semen collection from indigenous cattle breeds, horses, and the endangered Ethiopian wolf for the conservation of the animal species or breed. Therefore, animal conservation strategies should adopt and benefit from advances in animal reproduction and cryopreservation technologies. Furthermore, proper emphasis and attention should be given to the development and use of cryopreservation and reproductive technologies in the conservation of animal genetic resources. Therefore, the purpose of this review is to emphasize the commonly utilized reproductive technologies in the conservation and recovery of endangered and extinct animal genetic resources (AnGR). For the completion of this review and to clarify the significance of reproductive technology in AnGR conservation, a variety of published and unpublished sources were used.