| The problem
There is increased concern for the welfare of confined animals such as birds confined in battery cages. Criticisms have been leveled at the industry for not allowing these birds to meet their basic behavioral needs. According to some researchers, crowding of birds and the environment within the battery cage may result in increased stress, boredom, and fear, which may lead to increased mortality and decreased productivity.
Environmental enrichment
Various forms of enrichment stimuli are commercially available for chickens, however their usage has not been quantified. The usage of enrichment devices may increase with increased crowding. The use of a commercially available enrichment device (Agrotoy sold by AgroTop Ltd., Rehovot, Israel) and a small bell (used in pet bird cages) were investigated at the Poultry Research Center under three stocking densities ranging from 420 to 2100 cm2/bird for Shaver Starcross 288 Leghorn hens. The two environmental enrichment devices were suspended from fish line in front of each cage and their usage was recorded by video.
Results
The results indicated that for birds stocked at three different densities (one per cage [2100 cm2/bird]; two per cage [1050 cm2/bird] and five per cage [420 cm2/bird]), the number of total pecking observations was significantly different, whereas there was no difference in pecking observations on a per bird basis. The incidence of pecking directed to the bell was significantly higher (2.5 times) than those directed to the commercially available enrichment device. There was a significant increase in usage (18%) from week 1 to week 2. This suggests a gradual increase in enrichment device usage in response to a sudden change in environmental complexity, i.e., providing environmental enrichment. The results suggest that increasing stocking density to the recommended level does encourage increased usage of the enrichment toys. The birds at the higher stocking density did not appear to be more stressed when using fear, cannibalism or decreased production as an indicator.
Bottom line
Stressed leghorns used the chicken toys more frequently, and used the bell more than the plastic toy.
The results from this study have been published in 1994Journal of Applied Poultry Research 3:336-341.
John Feddes, University of Alberta
Poultry Research Centre News - Vol. 4 No. 3, 1995 |
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