Feather pecking among chickens can be reduced by half if their feathers are sprayed with a bitter substance. Unfortunately, pecking cannot be corrected, says Bas Rodenburg of the Animal Breeding and Genomics Centre.
However, the spray has to be used continually to reduce feather pecking. 'The research was an experiment to find out if we can inculcate into chickens the thought that feathers are dirty. Do the chickens retain this thought when the spraying stops? Unfortunately, they don't. You have to keep spraying the bitter stuff to get results.'
Yet, poultry farmers can benefit from this research. 'They can spray problematic pairs of laying hens with quinine or some other bitter substance to stop damages caused by feather pecking. If this can lead to less mortality among laying hens, such a treatment would have quickly earned its keep.' The German experiment worked with white Leghorns; other chicken breeds are also used in poultry farms. Rodenburg does not know whether the bitter substance also produces such good results in the farms. In Wageningen, his colleague Piter Bijma tries to select hens which lay many eggs and engage in very little feather pecking; this research project is still going on.