Cryopreservation of Canine Embryos

Abstract

The assisted reproductive techniques (ARTs) such as in vitro fertilization, embryo transfer, and cryopreservation of gametes have contributed considerably to the development of biomedical sciences in addition to improving infertility treatments in humans as well as the breeding of domestic animals. However, ARTs used in canine species have strictly limited utility when compared with other mammalian species, including humans. Although successful somatic cell cloning has been reported, artificial insemination by frozen semen to date is only available for the improved breeding and reproduction for companion and working dogs as well as guide dogs for the blind. We describe here the successful cryopreservation of embryos and subsequent embryo transfer in dogs. Canine embryos were collected from excised reproductive organs after artificial insemination and subsequently cryopreserved by a vitrification method. When the 4-cell to morula stage of cryopreserved embryos were nonsurgically transferred into the uteri of nine recipient bitches using a cystoscope, five recipients became pregnant and four of them delivered a total of seven pups. The cryopreservation of embryos in canine species will facilitate the transportation and storage of genetic materials and will aid in the elimination of vertically transmitted diseases in dogs. In addition, this technique will contribute to the improved breeding of companion and working dogs such as guide dogs, drug-detecting dogs, and quarantine dogs.

Current progress in oocyte and embryo cryopreservation by slow freezing and vitrification

“…The order Carnivora includes two suborders -feliformia (cat-like) and caniformia (dog-like Dresser et al (1988), the parallel report in dogs was only published two decades later (Suzuki et al 2009, Abe et al 2011. We were unable to find any publication on embryo cryopreservation in a non-domestic canid, other than a reference to an attempt to freeze blue fox (Alopex lagopus) embryos, cited as personal communication by Farstad (2000).…”

Fertility Cryopreservation

“…However, evolution made each species unique in many aspects, one of which is the development of highly specialized reproductive adaptation, a specialization that is part of the definition of a species. While thousands and thousands of offspring were born following the transfer of frozen-thawed embryos in humans, cattle, sheep, and mice, success is very limited in many other, even closely, related species (Abe et al, 2011;Aller et al, 2002).…”

Cryopreservation of Canine Embryos and Resulting Pregnancies

“…, ), recently, the first successful cryopreservation of embryos and subsequent embryo transfer in dogs have been reported (Abe et al. ). Because of the anatomy of the reproductive tract of the bitch and the related inaccessibility of the uterus from the vagina, surgical embryo transfer has proven to be the only adopted option (Tsutsui et al.…”

“…In this regard, successful embryo transfer with a non‐surgical technique in dogs has been reported (Abe et al. ). This article reviews recent advances for cryopreservation of canine embryos.…”