[Cognitive enrichment in zoo and farm animals--implications for animal behaviour and welfare].

Animals in the wild are facing a wide variety of challenges and ever-changing environmental stimuli. For successful coping, animals use both innate behavioural programs and their cognitive skills. In contrast, zoo- and farm animals have to cope with restricted husbandry conditions, which offer only few opportunities to adequately satisfy their various needs. Consequences could be sensory and cognitive underchallenge that can cause boredom and frustration as well as behavioural disturbances. Initially intended for improvement of management and husbandry, different forms of operant behavioural training have been applied firstly in zoo- and later also in farm animals. It has been suggested that successful coping with appropriate cognitive challenges is a source of positive emotions and may lead to improved welfare. Under the term cognitive enrichment, new approaches have been developed to integrate cognitive challenges into the housing of zoo- and farm animals. The present article reviews actual research in the field. Previous results indicate that, beyond improvement of management and handling routines, such approaches can positively affect animal behaviour and welfare. The combination of explorative and appetitive behaviour with successful learning improves environmental predictability and controllability for the animals, activates reward-related brain systems and can directly affect emotional processes of appraisal. For practical implementation in farm animal husbandry, it sounds promising to link individual access to e.g. automated feeders or milking systems with previously conditioned stimuli and/or discriminatory learning tasks. First experimental approaches in pigs, dwarf goats and cattle are available and will be discussed in the present article.