[Developmental trends in farm animal husbandry from an ethological point of view].

The current discussion on "semi-natural" or "extensive" animal production and husbandry shows that such terms are vague and are often used for various meanings. This paper addresses what can be referred to as natural environmental conditions from an ethological point of view, as well as the animal's environment in today's animal production, and how "near to nature" animal husbandry can realistically be. Apart from some outdoor systems with few ethological problems, the predominant part of milk and meat production in the future will still largely take place indoors. Thus, the development of housing conditions which are more appropriate to the animal's needs will still be an important issue of farm animal behaviour science. Consequently the essential environmental requirements of cattle and pigs derived from their species-specific behaviour are described and explained. In the future, an improved fulfillment of ethological requirements will lead to increased group housing in cold and open, structured barns with indoor straw-bedded lying compartments and integrated outdoor feeding and activity areas. This process will also be influenced by ecological, economic and technical aspects. Finally, several studies on cattle and pigs are presented which demonstrate the possible benefits from more appropriate housing systems or the fulfillment of single ethological requirements regarding behaviour, health, fertility and production of the animals.