Abstract
The inheritance and breeding results of hairless descendants of Mexican hairless dogs (MHDs) were investigated. When the male hairless dogs were bred to female beagles, the birth ratio of hairless and haired dogs was 1:1. Mating between MHDs gave both hairless and haired pups. The results indicated that an autosomal dominant monogenic gene was responsible for their hairless characteristics. We propose the symbol Hm for this gene (hairless, Mexican type). The survival rate of hairless pups was markedly lower than that of haired ones. It was elevated to 50-90% by warming their cages to a minimum of 25°C.