Coping strategies of cows in their stable and artificial stress situations considering the effect of social bonds

Keeping cattle in intensive housing systems is combined with stress due to crowding and competition. Space per cow is limited, herd size increases with the intensity of production and the composition of the herd changes frequently, which could result in poor social behaviour of the animals. For adaptation to these environmental situations, cattle have to develop individual coping strategies. For some years studies of social behaviour in farm animals have moved away from a dominant-subordinate classification. Questions of consistent behavioural characteristics or strategies based on the experience of each individual in agonistic and non-agonistic interactions are getting more attention. It has even been suggested that in terms of consequences for its physiological state and health, the strategy the animal adopts is probably more important than the actual social status achieved. Information on this topic in cattle is rare and incomplete. Additionally, little data exist in cattle on consistency in individual behavioural and physiological stress responses and the relation to the above mentioned coping strategies. The aim of this study is to evaluate fundamental behavioural and physiological data of different coping strategies in dairy and beef suckler cows in consideration of social bonds. The knowledge of behavioural structures, individual coping strategies and social bonds in cattle may allow to predict and manipulate levels of behaviour, such as aggression, in social groups. Management and housing design could be improved in order to allow the cows to perform effective coping behaviour, thus reducing stress responses. These modifications would enhance farm animal welfare.

The project identified different behavioural strategies in the social environment as well as coping types differing in their stress reactions in non-social challenging situations. However, social strategies seem to correspond hardly to coping types in challenging situations. Social bonding partners (friendship) had positive effects both on health in the long term and in stress situations. These results will help on pushing the development and implementation of housing systems in which durable social bonds between the cows are facilitated. Space per cow is restricted in indoor housing of cattle compared to pasture. The crowded situation as well as management procedures (e.g. regrouping, veterinary treatment) consistently result in challenging situations. To cope with these, the animals use different behavioural strategies. The project aimed at investigating such strategies, their consistency in different situations and possible similarities to strategies found in other species. Because social bonds play an important role in coping with challenge in humans and several species, such aspects were included in the project. Social behaviour of one dairy and one beef suckler herd was observed and three different groups of social strategy were identified: an "aggressive" group including high ranking cows, and two subdominant groups differing in behaviour but not in dominance value: "non-agonistic" cows were characterised by frequent licking other cows and avoiding conflict, while animals of the "agonistic-receiver" group more often initiated aggression. The three social strategy groups also differed in physiology and were consistent in a social challenging situation. Animals of both herds were tested in two challenging situations outside the herd. To investigate possible stress reducing effects of social bonding partners in such situations, the animals were also tested in presence of a social bonding partner or a non-bonded herd member. The social strategy groups differed scarcely in the behavioural and physiological stress reactions. However, reactions to the two challenging situations were consistent in physiology and behaviour. Thus, the social strategies seem to correspond hardly to coping strategies in (non-social) stress situations. In presence of a social bonding partner the behaviour differed (e.g. no cow vocalised in presence of her friend). This points at a stress reducing effect due to social support. Further studies are necessary to better characterise these coping types and strategies in different situations and, subsequently, continue to promote optimised herd management and housing systems leading to improved animal welfare.