Potentiel des races bovines locales dans les systèmes de pro­duction extensifs sur les terres marginales de la zone méditerranéenne

Industrialization and its consequences on the development of farm production (intensification of production in the suitable zones and marginalization of the others) have had particularly unfortunate effects on beef production economy (high costs and disparity between milk and meat production and demand) and on the potential and balance of the natural and human environments. A new rationality in the use of space could be envisaged in answer to this situation. It includes a more global approach to the functions of space in the needs of society both on the level of research and on that of its application. It implies, as far as cattle­breeding is concerned, that more efficient systems of exploitation of complementary fodder potentials be found on both a seasonal and regional basis, in particular betwen natural vegetation zones and crop­growing zones (by­products). The additional costs of fodder transport and stocking, the social constraints linked to the movement of animals point up the advantages of the use of local material that is often dying out but is suited to these conditions. Situations with regard to this differ greatly between the highly industrialized and underpopulated regions (the North­West Mediterranean zone) and the less highly industrialized zones with more rapid population growth (Turkey, North Africa). While the use of local races will, especially in the first case, concern the development of a beef breed by cross­breeding with beef­bulls taking into account the different genetic types' adaptation factors, in the second case the improvement both in milk and meat production in stock­farms where animals are milked is a priority. These considerations show how important it is to estimate the potential of local genetic material in extensive breeding systems when one takes into account the technological knowledge linked to the society's old habits in the use of this material.