Successful Cloning of Coyotes Through Interspecies Somatic Cell Nuclear Transfer (iSCNT) Using Domestic Dog Oocytes.

Interspecies somatic cell nuclear transfer (iSCNT) is an emerging assisted reproductive technology (ART) for preserving nature's diversity. The scarcity of available oocytes from some species makes utilization of readily available oocytes inevitable. Until now, no interspecies cloning has yet been successful in the Canidae family, mostly because of the domestic dog's unique reproductive physiology. In this study, we describe successful cloning of coyotes (Canis latrans) through iSCNT utilizing oocytes of domestic dogs (Canis lupus familiaris or dingo). Transfer of 320 interspecies reconstructed embryos into 22 domestic dog recipients resulted in six pregnancies, from which 13 coyote offspring were born. Eight of the newborn survived and are currently eight months old with good health. Fusion rate, pregnancy rate, and cloning efficiency during iSCNT cloning of coyotes were not significantly different (P > 0.05) from those observed during intraspecies cloning of domestic dogs in this study. Using neonatal fibroblasts as donor cells in recloning of male coyote resulted in significantly higher cloning efficiency (11.3% vs. 2.3%, P < 0.05) with lower stillbirth rate (14.3% vs. 33.3%) compared to cloning with adult fibroblast donor cells. The use of domestic dog oocytes in cloning of coyotes in this study has provided the promise of utilizing similar techniques to clone other endangered species in the Canidae family, subsequently leading to preservation of nature's diversity, but there still exist limitations to the iSCNT technology, as demonstrated by births of morphologically abnormal coyotes.This work was supported by a grant from Next-Generation BioGreen 21 program (No. PJ008054), Rural Development Administration, Republic of Korea.