Broiler - Broiler Welfare Issues

Broiler Welfare Issues

Broiler chickens may develop several health or welfare issues as a result of selective breeding. Broiler chickens are bred to be very large to produce the most meat per animal. Broilers bred for fast growth have a high incidence of leg deformities because the large breast muscles cause distortions of the developing legs and pelvis and the birds cannot support their increased body weight. Therefore, they may become lame or suffer from broken legs. The added weight also puts a strain on their hearts and lungs and ascites can develop. In the UK, up to 19 million broilers die in their sheds from heart failure each year.

Another issue with selective breeding of broilers is that the larger chickens have an increased appetite. The broiler chicks that are reared for meat are not usually feed-restricted as this would lengthen the time taken to reach slaughter weight. However, the parent birds which lay the eggs of the meat-producing birds also have an increased appetite and are feed-restricted to prevent them becoming overweight; this leads to behavioral issues in chronically hungry birds.

If the litter in the pen is not properly managed, it can become highly polluted with ammonia from the feces. This can damage the chickens’ eyes and respiratory systems, and because the heavier birds spend longer times resting, can cause painful burns on their legs (called hock burns) and foot ulcerations. Pastured or free-range birds which are rotated frequently typically do not have these problems.

Some broiler strains develop joint disorders, are very inactive, poor foragers, prone to predation, and are generally not suited to small free-range flocks. However, commercial free-range broiler flocks are now commonplace in Europe.

Broiler mortality in the U.S. in 2011 is estimated as 3.8%. However the 1925 figure was 18%.