Non-seasonal breeding appears dominant with incomplete penetrance in Australian Basenji dogs.

Domestic dogs (Canis familiaris) generally reproduce non-seasonally. However, the Basenji is an exception with seasonal breeding cycles, although some Basenjis can successfully reproduce outside of the breed's usual breeding season. There has been little investigation into the inheritance of non-seasonal breeding in canids, and the results remain inconclusive. Our aim was to predict the mode of inheritance of non-seasonal breeding in Australian Basenjis under a monogenic model. We purchased Australian registration records, which include a pedigree of 5796 Basenjis. This allowed us to confirm the breed's usual breeding season in Australia, which was from May to July, although 12.5% of litters were born outside this time. Based on the timing of litters, we assigned dams as seasonal or non-seasonal breeders according to whether they produced any litters outside the breeding season. We predicted the mode of inheritance of non-seasonal breeding using specialised software which uses segregation analysis to predict the mode of inheritance of a trait with incomplete penetrance. The pedigree and segregation analysis suggest that non-seasonal breeding could be dominant with incomplete penetrance in Australian Basenjis. These findings should help increase the power of future work identifying genetic markers involved in the control of seasonal reproduction in canids.