Inbreeding on litter size of German Spitz dogs

Abstract

Breeding and geneticsFull-length research article Inbreeding on litter size of German Spitz dogs ABSTRACT -The objective of the present study was to assess the association between the inbreeding coefficient (F) of German Spitz dogs (litter, sires, and dams) and number of live newborn dogs for this breed. Records of dams and sires of a breeding system were used to calculate the F of 105 litters and their sires and dams and the number of live newborn dogs. The analysis performed through the GLM procedure showed a negative influence of F of litter and mother on litter size. This influence was investigated through models that considered linear and quadratic influences. Although the model that considered quadratic effect of F of the litter achieved the best adjustment, only linear coefficients were significant in both analyses. According to these results, the studied sample of German Spitz dogs exhibits inbreeding depression for litter size, which is an important information for breeders and professionals that assist in dog breeding. In addition to all the known effects of inbreeding on canine health, the results indicate that monitoring inbreeding through F is important for the reproductive success of the breed.

Study of the Population Structure in Schnauzer Dogs

“…Inbreeding can limit the gene pool in a population, which contributes to deleterious genes becoming widespread and the pure breed, losing vigor. Reproductive traits are the most negatively affected, which goes against the interest of breeders that make profits with dogs that farrow easily and deliver larger litter [17]. As studied in cattle by Burrow [18] and in other animal species by Frankham [19], inbreeding depresses mating ability, female fertility, birth rate, survival rate, weaning rate, maternal ability, sperm motility and production, and percentage of normal cells, besides increasing the incidence of primary and secondary sperm defects and age for sexual maturity.…”