DOMESTICATED ANIMALS: PROBLEMATIC IN CONSERVING BREEDS Fernando Orozco Dept. de Produccion Animal; Area de Mejora Genetica. INIA, Madrid In a general review some basic pinciples are presented, such as: The reasons for preservation of definite populations -especially breeds-as well as the causes for the disappearance, or danger of loss, of many breds of domestic animals. Some points concerning the concept of bred and of other sub-populations within the species, and the contrast of lossing a breed compared with that of a species. Interest to preserve specific populations or genetic pools, its fundament. Difficulties to preserve animal compared with plant material. Economical and sociological problems involved in conservation. Differences between the problematic in developed or developing countries. Technical and scientific aspects of the breeds conservation are specially treated, with the corresponding references for more ampliation if needed. Basically, it is being considered the problem of maintaining the genetic variability to prevent the deterioration of small populations and to preserve the pretended special characterization of each breed. Population size, level of inbreeding and heterozygosity, loss of specific genes, etc., are some topics of main concern. It follows a brief review of some ways to preserve genetic material other than by maintaining live animals; cryopreservation technologies for gametes, embryos, stem cells and segments of DNA; with reference to their intrinsic limitations. It is included a review of the most important ways or systems to carry out the conservation of populations of live animals belonging to endangered breeds. Programmes supported by public or private funds, with their advantages and disadvantages or limitations in both cases, and information drawn for their results during the last years; the more positive approach being that with programmes run by both types of support, with diverse roles played by each side. Convenience of participation of the grower sector: livestock farmers or fancier breeders associations. Type of organizations in charge of conservation programmes, at regional, national and international level, and their convenient collaboration. Different programmes according to species, mainly in basis to their cost and management, or in basis to the animals included being "for accompaniment", "ornamental", "hobby", etc., or somehow productive. Some examples of programmes now in action with proposals for new ones, plus comments on the actual situation of the problem are finally reported. References F.A.O./U.N.E.P. Publications, Rome 1975. Estudio Piloto sobre Conservacisn de Recursos Geniticos Animales. 1983. Animal Genetic Resources Information. Bull. 1. 1985. Animal Genetic Resources Information. Bull. 4. 1986. Animal Genetic Resources Information. Bull. 5. 1991. Animal Genetic Resources Information. Bull. 8. 1992. Animal Genetic Resources Information. Bull. 9. F.A.O. Animal Genetic Resources. Animal Production and Health Papers. Rome. 1984. Conservation by management, data banks and training; paper 80 1984. Cryogenic storage of germplasm and molecular engineering; paper 44/2 1990. A global programme for sustainable development; paper 80. Genetic conservation of Domestic livestock, CAB International. Wallingford. U.K. Vol I. 1990. Edit L. Alderson. Vol II. 1990. Edit L. Alderson, and I. Bods. Proceedings of World Congresses on Genetics Applied to Livestock Production. 1st Congress. 1974. Round Table on "The Conservation of Animal Genetic Resources". Vol II, pp. 13-93. Madrid, Spain. 2nd Congress. 1982. Round Table on "Breeds Conservation". Vol VI, pp. 73-135. Madrid, Spain. 3rd Congress. 1986. Round Table and Symposium on "Preservation and Management on Genetic Resources". Vol XII, pp. 471-500 and 503-534. Lincoln, Nebraska, USA. 4th Congress. 1990. Workshop & Contributed Papers on "Conservation of Genetic Resources". Vol XIV, pp. 423-472 and 475-499. Edinbourgh, U.K. J.N.B. Shrestha (edit.). 1992. Proceedings of the First National Workshop in Conservation of Animal Germplasm. Agriculture Canada. Ottawa, Canada.