Genetic diversity of free-living and domesticated livestock species should be preserved for future generations for scientific and breeding reasons. Among the many advocates of wild species conservation, few realize that the number of different breeds and varieties of farm animals, including poultry, is declining rapidly. However, those in favour of saving breeds from extinction have encouraged some fancy breeders to make efforts to save rare, historically important breeds, especially hens and turkeys. Biodiversity of these two avian species is at greater risk than that of other farm anitnals (cows, pigs, sheep, goats and horses) because in recent decades the exceptionally rapid development of intensive poultry breeding and production has been based on a limited pool of genes. A threat to the genetic diversity of poultry goes far beyond the amateur and commercial populations. In recent years many poultry flocks, geentically selected and investigated in research centres, have been lost or are facing extinction. Despite FAO and UNDP recommendations on the protection of experimental populations of animals, many countries adopted no official conservation plans and many populations are lost or in danger of extinction. This is because researchers retire or there are no funds to keep the populations. The disappearance of these specialized populations limits the scope for genetic improvement of different species of commercial birds, hindering the advance of agricultural, biomedical and biological sciences. The extinction of rare populations characterized by different genetic traits is a matter of concern because it may involve the loss of genes controlling unique traits among the populations. Genetically diverse populations of hens, turkeys and Japanese quail are of ten used as model organisms in basic and applied research on vertebrate biology. Particularly useful are avian flocks characterized by different mutations of single genes and inbred lines. They are used in biomedicine as the models to study hereditary genetic defects in humans, such as glaucoma, macula degeneration, limb defects, cleft palate, muscular dystrophy, autoimmune forms of thyroid inflammation, vitiligo and scleroderma. Essential to poultry production are the populations improved for productive traits such as egg production, body conformation, nutrient conversion efficiency, limb strength, and resistance to diseases. It is likely that a lack of funds may make these intensively selected populations particularly vulnerable, because their genetic improvement needs many years of efforts and a relatively large number of birds in each generation.
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