A study was conducted into the spacing behaviour of hens, and the effects of limited space availability on behaviour. The concept of behavioural need and the motivational aspects of spacing behaviour are discussed, along with implications for hen welfare. Familiarity and aggression were the main social factors determining local bird distribution. Familiar birds tended to associate more closely than strangers, though hens preferred visual contact with a stranger to isolation. If given the opportunity, groups of at least 40 hens could recognise each other and would defend their common territory. Within each group, smaller sub-groups tended to occupy core areas within the territory. The effects of familiarity between birds remained evident over several weeks of study. The space around birds was correlated with social status and aggressiveness. In floor pens, increases in group size and stocking density resulted in increased aggression. These increases did not particularly affect the lower ranking birds. Time budgets of hens were affected by space allowance, with small cages restricting behavioural expression. The behaviour patterns most affected were those with elastic demand, but in the smallest cages there was also an effect on food consumption. Behavioural freedom was affected by quite small increases in cage size, while larger increases affected only certain behaviour patterns, e.g. walking. Space increases also affected the way behaviour was performed, allowing more complete expression in more natural ways. In unrestricted environments there was a tendency for group activities to be synchronised, which was increasingly limited as space was restricted. Motivation to synchronise was most evident during feeding. Birds which were unable to feed with the others often showed signs of frustration, with particular individuals tending repeatedly to be the ones excluded.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:652990 |
| Date | January 1995 |
| Creators | Jenner, Thomas Detmar |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/12291 |
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