Using motivation to feed as a way to assess the importance of space for broiler chickens
This paper describes a novel combination of feeding motivation and spatial preference testing. We used the feeding motivation test to determine a [`]low’ barrier height that broiler chickens, Gallus gallus domesticus, that were not food deprived would cross to get to food, and a [`]high’ barrier height that food-deprived chickens would cross to get to […]
Forced to crowd or choosing to cluster? Spatial distribution indicates social attraction in broiler chickens
We investigated the response of commercially farmed broiler (meat) chickens to their social environment at five stocking densities, using spatial distribution and behaviour. We used a computer model in which a [`]social aversion/attraction’ parameter was set at different values to give simulations in which the chickens were averse, indifferent or positively attracted to each other. […]
The myth of a simple relation between space and aggression in captive primates
Abstract 10.1002/zoo.1430080514.abs This paper reviews literature on the relation between captive environments and social behavior, particularly aggressive behavior, in monkeys and apes. The conclusion is that theories of “crowding” and “stress” are too simplistic to account for the observed relation. Instead, it is suggested that environmental effects be investigated from the standpoint of behavioral adjustment. […]
What causes crowding? Effects of space, facilities and group size on behaviour, with particular reference to furnished cages for hens
Theoretical models are presented of the effects of space, facilities and group size on the behaviour of chickens at high stocking densities, with relevance for all animals. The appropriateness of each model is supported by published data, although such data are scant for some important variables. Freedom of movement is analysed by taking the area […]
Crowding increases salivary cortisol but not self-directed behavior in captive baboons
Reduced space can lead to crowding in social animals. Crowding increases the risk of agonistic interactions that, in turn, may require additional physiological defensive coping mechanisms affecting health. To determine the stress induced from increased social density in a group of nineteen baboons living in an indoor/outdoor enclosure, saliva cortisol levels and rates of anxiety-related […]