So-called higher welfare broiler rearing programs are a trend that is increasing in Northern Europe, according to leading researchers.
Dr. Ingrid de Jong, a senior scientific researcher at Wageningen University & Research, and Dr. Jerine van der Eijk, a researcher at Wageningen University & Research Livestock Research, gave a presentation on the characteristics of welfare-friendly broiler chicken production at 2021 Eurotier Digital on February 11, 2021.
Welfare inspired purchase commitments
There is a trend towards what de Jong called middle segment welfare systems: those that have standards somewhere between conventional and organic broiler growing programs. Current purchase commitments and future purchase commitments by large foodservice and food manufacturing companies to “enhance welfare” in production, like the Better Chicken Commitment, are driving interest in methods for improving broiler welfare.
Many of the schemes require breeds that grow at less than 50 grams per day. This is often accomplished by crossing a modern strain of broilers with a slower growing breed. Some schemes call for the genetics to be 100% slow growing. In any event, the birds will take longer than conventional broilers to reach slaughter weight, generally at 49 days of age or more.
In research comparing slower growing breeds with fast growing breeds, raised under similar conditions, de Jong said that the slower-growing breeds had better gait scores, better scores for hock and footpad dermatitis and have cleaner feathers. Slower-growing breeds also exhibited reduced incidence of breast meat myopathies at slaughter.
So-called higher welfare rearing programs have restrictions on housing density. The Better Chicken Commitment restricts housing density to no more than 6.15 pounds per square foot (30 kilograms per square meter). Flock thinning, or removing some of the birds for early slaughter to give the rest of the flock room to be grown to a higher weight, is discouraged.
The use of environmental enrichments such as bales of hay or alfalfa, perches, or raised platforms are required in these schemes. Providing birds an uninterrupted 6 hours or more of darkness per 24 hours is also usually required.
Even in existing houses, welfare can be significantly increased by use of slower-growing strains, reducing stocking density and providing environmental enrichments, according to de Jong.
Van der Eijk, provided an updated definition of environmental enrichments:
- Environmental enrichment should increase species-specific behavior.
- It should maintain or improve levels of health.
- It should improve the economics of the production system.
- It should be practical to employ.
- Environmental enrichment should be biologically relevant.
- Economics and practical issues should not be the first consideration.
Bales of hay, wood shavings, straw or alfalfa are some of the most popular enrichments for poultry. Birds can exhibit foraging behavior while pecking the bales and the can also rest on top of, or shelter around, the bales. Bales are generally used by fast- and slow-growing broilers, they increase species-specific behavior, but use of bales is not without issue, according to van der Eijk.
Perches have been used in various shapes and sizes and materials. Round, square, plastic, metal and wood have all been used. Research shows unlike their frequent use by table egg laying hens, fast-growing broilers make limited use of perches and sometimes have difficulty perching.
Platforms can be simple raised structures made of plastic grates or metal plates. Platforms promote resting on an elevated structure, which is a species-specific behavior. Research shows platforms are well used by both fast- and slow-growing broilers and they increase bird activity while reducing fear, but they have not been shown to consistently improve leg health.
Of the objects that have been introduced to broiler houses for the birds to peck at, van der Eijk said that pecking stones are the most successful form of pecking enrichment. Overall, she said that length conditions, stocking density, number and distribution of enrichments in the house, combinations of enrichments and the breed of the bird all play a role in how much the flock interacts with the enrichments.