Management of European sheep and goat genetic resources
1997
Gabina, D. (Centre International de Hautes Etudes Agronomiques Mediterraneennes, Zaragoza (Spain). Instituto Agronomico Mediterraneo de Zaragoza)
The European sheep population, estimated at around 220 million head, can be considered to have wide genetic variability both in phylogenetic origin, adaptability to different climates and production systems and also in purpose and productive specialisation. The maintenance of extensive or semi-extensive production systems, where adaptation to the environment is necessary, together with little use of artificial insemination in sheep, are just some of the causes of this situation. As a consequence, crosses have generally been limited and the absorptions or substitutions of some breeds for others are not frequent. Besides, in those breeds where selection schemes have been set up, the danger of a strong decrease in genetic variability does not seem to arise since selection is generally carried out from a selection base of a large number of animals from many flocks in different environmental and production conditions. Regarding the goat population in Europe, currently of approximately 29 million head, the overall situation is comparable to that of the sheep population, although in the South of Europe, when intensive systems are developed for milk production, a small number of very productive genotypes are used. Concerning the management of genetic resources in goat breeds undergoing selection, this selection is only important in a few dairy breeds where, on the other hand, a correct resource management is carried out. Concerning conservation of genetic resources, inmost Western European countries central or regional administrations are becoming aware and taking measures to avoid the disappearance of breeds. In Eastern Europe and Turkey the lack of infrastructure and funding means may stop from taking efficient solutions.
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