Circulation fans reduce severity of footpad dermatitis
Lesions created by footpad dermatitis are significantly reduced when broilers are raised in poultry houses with circulation fans, scientists have discovered.
Researchers at the University of Maryland found birds raised in houses with fans suffered from less severe cases of footpad dermatitis, which adversely affects bird welfare and the market for broiler paws.
“Footpad dermatitis causes painful ulcers and lesions on the ventral footpads of broilers,” graduate research assistant Zoie McMillian told Poultry Health Today. “This is a threat to poultry welfare as well as a threat to the meat industry. When footpads have lesions on them, the paws are not saleable, and there’s a big foreign market to purchase broiler paws.”
Fans versus no fans
In a study to look at the impact of using circulation fans, McMillian and her colleagues used four broiler houses with 36,000 birds in each house. Two of the houses were equipped with 16 high-capacity circulation fans located in the ceiling. The fans ran during cold weather when winter ventilation was already in operation. The other two houses did not have these fans.
“Generally, the reason for footpad dermatitis is moisture and irritants in the litter,” McMillian said. “The purpose of the circulation fans is to help dry the litter, keep temperatures even and keep humidity levels where we want them.”
McMillian and her colleagues then caught 80 birds in each of the houses and analyzed their footpads. Lesion scores were given to each bird with 0 for no lesions, 1 for moderate and 2 for severe lesions.
The team went further with scoring and used a Lumix digital camera to photograph each bird’s footpads and hocks. The photos were then put into special software that determined the percentage of the footpad with lesions. This helped the team better determine severity of the dermatitis.
“We can look at severity…and actually have a number of how large it is, like 20% of the footpad,” McMillian said. “It can give us a more specific idea of how bad the issue is on an individual-bird basis.”
Circulation fans lessen lesions
The results were clear: Footpad dermatitis was less severe in houses with circulation fans compared to houses without the fans. The results came from both visual scoring and digital analysis.
“In the houses without fans, we saw birds with a larger range of lesion sizes…and birds with 20% to 30% of their footpads covered in a lesion,” McMillian said. “That’s a pretty severe lesion. We didn’t see anything like that in the houses with the circulation fans. I think this is a really clear difference.”
However, the cost of these high-capacity fans could deter some producers from using them. “The energy cost of running fans long term is important to think about,” she added.
“There’s also the decision of when’s the best time to run these high-capacity circulation fans,” she continued. “They make the most impact on litter moisture when the birds are young because the litter is not covered by large broilers. If you can do that while they are young, then those benefits carry over to when the birds reach market weight.”
Another reason for using the fans is better bird welfare, McMillian added, which is important to both producers and consumers.
Posted on July 22, 2022