Most welfare concerns are linked to fast growth rates, a result of genetic selection in chickens, E.F.S.A.’s experts said. They also identify concerns originating from the interaction of genetic traits and the chickens’ environment – for instance, the housing and management of poultry farms. These opinions will help the European Commission prepare a report, which will be submitted to the European Parliament and to the Council.
During the second half of the 20th century, the growth rate of broilers increased four times –mainly as a result of genetic selection. Although it is generally accepted that welfare problems in these chickens are caused by genetic selection aimed at increasing their productivity, genetic selection can also offer an opportunity to improve their welfare and robustness.
Genetic selection of chickens now includes aspects related to welfare; however, improvements or otherwise in this area are difficult to quantify because robust data are not available. Experts on E.F.S.A.’s A.H.A.W. panel stressed a need to develop and monitor welfare indicators in broiler flocks to measure welfare changes. They also stressed the lack of harmonized quantitative data in Europe to fully evaluate the impact of genetic selection, and the impact of the system of husbandry and management of broiler breeders on birds’ welfare. Experts are calling for systematic data collection and surveillance systems to be put in place.
Experts considered the peer-reviewed scientific literature and also analyzed information gathered in consultation with stakeholders, such as the poultry industry, breeding companies, research groups and non-governmental organizations.
Major welfare concerns identified and associated with genetic selection for broilers were skeletal disorders leading to problems such as lameness, contact dermatitis, irregular body shape and sudden-death syndrome. These concerns are mostly linked to fast growth rates and lead to poor welfare. Experts noted differences between countries, regions and different farming systems.
Broiler welfare could be improved, particularly if birds are genetically selected to withstand the environment they live in. For example, birds that grow more slowly should be selected for hot climates as fast-growing broilers are susceptible to heat stress.
Regarding the genetic selection of chickens, high priority should be given to decreasing the number of lame birds and reducing contact dermatitis. These are important welfare problems that involve genetic predisposition and environmental conditions.
Due to selection for fast growth and high muscle yields, breeders have a very high food intake. As a result, feed restrictions are necessary to limit growth rate to maintain good health. Experts recommend the competition for food, which can be observed among chickens when feed is not provided, should be minimized, thereby reducing related injuries. Experts also recommend birds requiring fewer feed restrictions should be selected as future breeders.