Aerial Perches Improve Free-Range Layer Welfare

Providing access to aerial perches in free-range houses improved welfare in the first half of the laying cycle, according to research presented by Dr Caroline Nicholson¹ of Queen's University in Belfast. She explained that this was evident from an apparent reduction of fearfulness towards humans and a tendency to show less aggressive social behaviour.

Dr Nicholson explained that the European Directive on layer welfare requires the provision of 15cm perch space per bird but that the Member States have put somewhat different interpretations on the nature and positioning of the perches. Furthermore, no research had been carried out on the welfare implications of aerial perches in a commercial setting, so she and colleagues recorded and assessed hen behaviour in four commercial houses that had been divided into two sections, one with and one without aerial perches.

Dr Nicholson reported that providing access to aerial perches significantly reduced the flight distances of the birds and the tendency towards less feather-pulling behaviour. No differences were observed between the groups in terms of aggressive behaviour, feather picking or feather pecking, however.

Dr Nicholson concluded: "Perches aid welfare because the birds were less fearful of visitors and they had a reduced tendency to harmful behaviour.

Seeking the Best Water Provision for Ducks

Overall, the provision of water in a trough or bath seemed to be the best in terms of duck welfare, as well as resulting in increased liveweight, according to Professor Donald Broom² of the University of Cambridge in the UK.

Dr Broom presented data from two studies carried out with K. O'Driscoll, both using Pekin ducks starting at 21 days of age and housed in pens of straw litter on a solid concrete floor. The area under the drinkers was slatted in each case.

In the first study, the ducks were provided with water either from nipple drinkers or from a wide-brimmed bell drinker. Type of water source did not affect final liveweight, feather hygiene score or foot pad dermatitis score. However, those with the bell drinkers had a significantly worse gait score although the researchers were unable to identify any cause of this from the bedding. There was no effect of the water provision on the frequency of blocked nostrils.

The second study was similar to the first but it compared a narrow bell-drinker, a trough and a bath as the water sources. At the end of the experiment, the birds with the trough were heavier than those with the bell-drinker, with the bath being intermediate. Dirty and blocked nostrils were more often observed for the birds with the narrow bell-drinker than with the trough or the bath.

None of the treatments resulted in eye health problems in these studies.

Professor Broom concluded that the trough or bath offered better welfare conditions for the ducks but providing these facilities in practice requires further work.

Broiler Breeders Fail the Food Test

Feed restriction appears to affect negatively the ability of broiler breeders to learn a feed quantity discrimination task, according to research presented in Belfast by Louise Buckley³ of Scottish Agricultural College. The experiment was part of her PhD study. However, she went on to suggest that Y-maze tasks are not suitable for determining the food preferences for hungry broiler breeders because 80 per cent of the birds fed almost ad libitum failed to learn the task.

Ms Buckley explained that hunger is a welfare issue for feed-restricted broiler breeders, and that preference tests have been proposed as a tool to identify whether quantitative or qualitative feed restriction would be better for the birds from the welfare point of view. The aim of this study was investigated the effect of the degree of feed restriction on a broiler breeder's ability to learn a Y-maze feed quantity discrimination task.

Ms Buckley concluded that feed restriction appears to reduce the birds' cognitive capacities.

References

All papers were presented at the World's Poultry Science Association (UK Branch) Annual Meeting in Belfast in April 2010.

1. Nicholson C.J. and N.E. O'Connell, 2010. Influence of access to aerial perches on welfare indicators in free-range laying hens.
2. O'Driscoll K.,and D.M. Broom. 2010. The effect of water resource type on measures of duck (Anas platyrhynchos) health and other aspects of welfare.
3. Buckley L.A, I.M. McMillan, V.S. Sandilands, B.J. Tolkamp, P.M. Hocking and R.B. D'Eath, 2010. Too hungry to learn? Hungry broiler breeders fail to learn a food quantity T-maze discrimination task.

September 2010