Breeding Methods and Technical Key Points for White Raccoon Dogs

I. White Raccoon Dogs and Their Characteristics

Raccoon dogs in nature have always been dark brown; this common ordinary color type is genetically known as the wild type. In 1974, the Harbin Zoo in Heilongjiang Province acquired a rare male white raccoon dog (eyes and muzzle both pale pink). In 1980, among domesticated raccoon dog populations in the three northeastern provinces, white raccoon dogs or piebald raccoon dogs with yellow-brown or pale blue eyes and black muzzles were successively discovered. These special color types differing from the wild-type coat color are called mutant types. Using these valuable white raccoon dog mutant genes, the Institute of Special Animal and Plant Sciences of the Chinese Academy of Agricultural Sciences, after nearly 10 years of research, finally succeeded in breeding the new white raccoon dog color type now existing in our country.

The new white raccoon dog color type now existing in our country is further divided into two types based on phenotype: one type has the wild-type raccoon dog coat color only around the eye rims, ear edges, nose tip, paws, and tail tip, while the guard hairs and underfur on all other parts of the body are white; the other type has guard hairs and underfur on all parts of the body white. Both types of white raccoon dogs have attractive coat colors, do not differ significantly in body size from ordinary-colored raccoon dogs, and are more docile in behavior than ordinary-colored raccoon dogs.

II. Characteristics of Coat Color Inheritance in White Raccoon Dogs

Extensive research shows that the gene for white coat color in raccoon dogs is a dominant gene (W), and its corresponding wild-type gene is a recessive gene (w). However, the white dominant gene in raccoon dogs has a homozygous lethal effect, so all white raccoon dog individuals are heterozygotes (Ww). The coat color segregation when white raccoon dogs are mated with white raccoon dogs or wild-type raccoon dogs is as follows:

(1) White raccoon dog x white raccoon dog (2) White raccoon dog x wild-type raccoon dog

　　（Ww）↓（Ww）（Ww）↓（ww）

　　WW+Ww+wwWw+ww

Lethal White raccoon dog White raccoon dog Wild-type raccoon dog White raccoon dog Wild-type raccoon dog

It can be seen that when white raccoon dogs are mated with white raccoon dogs, only 1/2 of the offspring are white raccoon dogs; due to the homozygous lethal effect of the dominant gene, their reproductive capacity is also reduced. When white raccoon dogs are mated with wild-type raccoon dogs, the offspring also segregate 1/2 white raccoon dogs, but the consequence of homozygous lethality of the dominant gene is avoided.

III. Selection of Breeding Stock and Mating Pairing for White Raccoon Dogs

The coat color of the white raccoon dog type currently in our country is already very stable, that is, the white-haired parts, whether guard hairs or underfur, are entirely white, with no other mixed colors (such as guard hairs white but underfur not white or partially not white; or some part of the body not white, etc.). Therefore, selection of white raccoon dogs should focus on coat color, coat quality, and body size, and male raccoon dogs especially should be carefully selected.

For mating pairing of white raccoon dogs, it is advisable to mate white raccoon dogs with wild-type coat color raccoon dogs, and inadvisable to pair white raccoon dogs with each other. White raccoon dogs generally have the shortcoming of coarse and long guard hairs; the wild-type raccoon dogs selected for mating should preferably have short and dense guard hairs to correct the shortcomings of white raccoon dogs.