How do cattle cope with social competition?

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Concern about the welfare of farm animals in individual housing has led to increased use of group housing but economic pressures result in large group sizes and high social density. Animal welfare standards limit group size or densities but there is controversy as to what these should be. Quantitative measures of social density (e.g. number of animals in a given area) assume that all animals are identical but animals differ greatly in how they respond to social competition. We know little about social strategies of farm animals kept at high densities and have few tools to ameliorate the effect of social competition. Social competition is usually thought to be regulated by dominance relationships, but social relationships between animals can be more subtle. Domesticated species normally live in groups and have evolved strategies to adapt to their social environment. We need to understand these social abilities and profit from them. In dairy production, animal welfare is most at risk for the milk-fed calf and the periparturient cow. Animal welfare concerns and economic pressures favour the use of group housing for these animals, but recent studies show deleterious effects of stocking density on access to resources. However, we remain largely ignorant of the nature of social relationships between cattle, or their abilities to ameliorate negative effects of social competition. The objectives of this proposal are to examine whether 1. intensively-housed lactating cows and milk-fed calves form affiliative social relationships based on spatial proximity, and preferred grooming or playing partners. 2. these affiliative relationships reduce the effect of social competition over resources. 3. cattle classify group companions as either dominant or subordinate or affiliate or competitor. 4. cattle are able to re-schedule their motivational priorities to avoid social competition. I will examine the distribution of agonistic and affiliative behaviours within groups of cattle in commercial conditions, and explore whether competition over resources is reduced in groups with a large percent of affiliative relationships. I will also explore the way that cows classify each other as either familiar/unfamiliar, dominant/subordinate or affiliative/competitor.