Successful transfer of the embryos of Przewalski's horses (Equus przewalskii) and Grant's zebra (E. burchelli) to domestic mares (E. caballus)

Abstract

Blastocysts were collected non-surgically from 2 Przewalski's horse and 2 Grant's zebra mares and transferred extra-specifically to domestic horse and donkey recipients. Nine Przewalski's horse embryos were transferred surgically, and 2 non-surgically, to domestic Welsh-type pony mares. After surgical transfer, 7 (77.8%) pregnancies were established and 4 foals were born. Twelve Grant's zebra embryos were transferred surgically to 5 pony and 7 domestic donkey recipients respectively and 1 non-surgically to a donkey; 3 (60%) zebra-in-horse pregnancies were established and 2 went to term. Only 2 (28.6%) zebra-in-donkey pregnancies were established but neither went to term, although one zebra foal was aborted alive at Day 292 but failed to survive. No pregnancies resulted from the non-surgical transfers. Measurement of chorionic gonadotrophin concentrations and parental-specific lymphocytotoxic antibodies in the serum of the recipient animals indicated a pronounced maternal immunological response to the extra-specific embryo, but this could not be correlated with success or failure of pregnancy. The results indicate that extra-specific embryo transfer may be a useful aid to breeding exotic equids in captivity.

Reproductive biotechnologies for endangered mammalian species

“…Embryo transfer of gaur (Bos gaurus) embryos in Holstein cows was the first successful interspecific embryo transfer [64]. Other examples concern wild horse embryos transferred into domestic horses [65], Indian desert cat embryos (Felis silvestris) transferred into domestic cat (Felis catus) [54], mouflon embryos (Ovis orientalis) into domestic sheep (Ovis aries) [19]. Successful interspecific-bispecific transfers (Spanish ibex embryos (Capra pyrenaica) + goat embryos) into the domestic goat have also been reported [18].…”

Interspecies embryo transfer in camelids: the birth of the first Bactrian camel calves (Camelus bactrianus) from dromedary camels (Camelus dromedarius)

“…The present study provides the first evidence that for Old World Camelids, which all have 37 pairs of chromosomes, it is possible to conserve one species using the other. Interspecies embryo transfer has been used successfully between alpaca and lama (Godke 2001), cow (Bos taurus) and zebu (Bos indicus; Summers et al 1983), banteng (Bos javanicus) and cow (Bos taurus; Solti et al 2000), horse, donkey, Przewalski's horse and Grant's zebra (Summers et al 1987;Allen et al 1993), moflon (Ovis gmelina musimon) and sheep (Ovis aries; Dixon et al 2007), Spanish ibex (Capra pyrenaica) and domestic goat (Capra hircus; Fernandez-Arias et al 1999) and Indian desert cat (Felis silvestris) and domestic cat (Felis catus; Pope et al 1993). It has been suggested that similarities in reproductive physiology, duration of gestation, placentation, number of chromosomes, generation of fertile progeny after hybridisation and comparable body size are important factors for successful interspecies embryo transfer (Summers 1985).…”

Detomidine and Butorphanol for Standing Sedation in a Range of Zoo-Kept Ungulate Species

“…Equine species can carry extraspecific pregnancies, and both horse and donkey brood mares have successfully delivered implanted zebra embryos at term. 43 Dystocia appears to be uncommon. 44 …”