Measuring Behavior 2005: Collins

The Virtual Raceway Method: A novel method for assessing perception in the social environment

L.M. Collins

Department of Zoology, University of Oxford, Oxford, UK

An animal’s social surroundings are complex and dynamic. Captive animals that are kept at high stocking densities, such as the commercial broiler chicken, are forced to live in close proximity to thousands of other individuals. How do the birds themselves perceive this kind of environment? Whether high stocking densities are as distressing to animals as we humans think they are, is one of the most urgent and controversial issues in farm animal welfare, and is extremely difficult to answer with our present methodology. The experimental raceway method is used by researchers to test for aversion to certain stimuli. Here I have developed and used a new in situ virtual raceway test that involves following the paths of individual birds from video footage taken inside commercial broiler houses. This method allows researchers to track behavior in the place where there is concern for animal welfare.

Despite the widespread availability of video and CCTV, relatively little attention has been given to how to analyze it in terms of what it can demonstrate about the preferences and aversions of the animals concerned. I tracked broilers inside 20 UK commercial broiler houses using virtual raceways to observe behavioral differences between houses with different manipulated target stocking densities. Using the virtual raceway method, I demonstrated that broilers are influenced by their social environment. A focal bird’s body orientation with respect to neighboring birds was affected by what these birds were doing (F10, 881=7.41, p<0.0001). Neighbor behavior and stocking density also influeced focal bird behavior (F10, 886=3.03, p=0.01, and F4, 886=7.88, p<0.0001, respectively). It is hoped that this method will be easily transferable between different species, permitting us a valuable insight into how animals view their social surroundings.

Paper presented at Measuring Behavior 2005 , 5^th International Conference on Methods and Techniques in Behavioral Research, 30 August - 2 September 2005, Wageningen, The Netherlands.