Avian genetic diversity: Domesticated species

GENETIC DIVERSITY IS CONSIDERED crucial to the continued survival of a species, be it wild or domestic. Such within-species diversity has been the raw material of agriculturists over millennia. In response to selective breeding and the differential survival of less fit animals, preferred traits have been accentuated and clustered to produce distinct breeds and varieties of the modern domesticated species (NRC 1993). In more recent times, researchers have deliberately isolated various mutations in specialized stocks, permitting the systematic study of such mutations and promoting a better understanding of the normal function of the affected genes. The totality of wild and domesticated species form the gene pool or genetic resources base necessary for the survival of the species. The genes and genotypes present in this pool represent genetic resources which are accessible and can be exploited by biologists and breeders. In this report, we emphasize “genetic stocks” which have been bred for specific traits and genes in contrast to breeds in which the individual birds have many traits in common and can generally be maintained with randomly breeding populations. Genetic stocks are typically selected for traits of special interest to breeders and geneticists. Many of them are reproductively, physically, or physiologically compromised, and require special care in breeding and management, even for maintenance or conservation purposes.