Breeding Legacy of Lame Chickens
More than a quarter of broiler chickens have difficulty walking as a consequence of huge increases in growth rates among the intensively-reared birds, research funded by Defra showed today.
The study of 51,000 birds within 176 flocks belonging to five major UK producers, who account for more than half of chickens produced in the country, revealed that at an average of 40 days, 27.6 per cent showed "poor locomotion" and 3.3 per cent were almost unable to walk.
In a paper published in Public Library of Science, the scientists said there was evidence birds with that level of mobility problems can be in pain.
The researchers from the University of Bristol said the primary risk factors associated with difficulty walking were increased growth rates - which have risen by 300 per cent from 25g a day to 100g a day over the past 50 years.
Elements causing problems included the age and breed of bird, not being fed whole wheat, shorter dark periods during the day, higher density of animals, no use of antibiotics, and the use of intact feed pellets, many of which had an impact on growth rates.
The high prevalence of poor locomotion and leg health problems occurred despite culling policies by the farmers to remove severely lame birds from flocks.
The researchers said the findings of the study had "profound" welfare implications for the rearing of chickens for meat, most of which are confined for their lifetime in high density housing and reared from hatch to slaughter weight in around 40 days. …