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Nutritional influences on foot pad dermatitis

Pododermatitis, more commonly known as foot pad dermatitis, is a complex problem that will affect every farm at some point. It can seriously affect broiler performance as well as having welfare implications for the poultry industry.

Poultry World considers the nutritional factors involved and how producers can look to reduce the incidence of foot pad dermatitis.  

Foot pad dermatitis (FPD) is often referred to as foot pad burn due to the lesions it causes, explains David Beavis, ABN’s National Poultry Specialist. “Foot pad burn is viewed to be such an important issue that it is now seen as a welfare indicator and the industry has implemented a scoring system to monitor the incidence on farm.”

He explains that wet litter is often seen to be one of the main causes of FPD, which is why there tends to be a higher incidence in the winter, when the occurrence of wet litter is more likely. “Although this is not the whole issue,” warns David, “It is often seen to be a key factor. We also need to be aware that management and the environment have a bearing on the incidence of FPD.” By looking at the causes of wet litter on their farm, most farmers will make progress in reducing pododermatitis, he notes.

John Round, ABN Poultry Nutritionist outlines the causes of FPD in his opinion. “There is no one single cause; management, nutrition, disease challenges and breed all interact to cause FPD.“

Protein effects on wet litter

With wet litter being seen to be one of the fundamental causes of FPD, it is vital to consider the effects of nutrition on litter condition, says John. Higher protein levels in the feed are associated with higher levels of water intake on farm and these in turn are associated with higher levels of moisture in the litter.

It is also important to consider the digestibility of protein when formulating a diet, as poorly digested protein leads to an increase in nitrogen being excreted onto the litter, which can increase the ‘burn’ aspect of FPD.  In addition, it is important to specify diets which have an optimum profile of amino acids in relation to the bird’s requirements; this will improve feed conversion efficiency and help to maintain good litter condition.

“Diets high in soya, which is high in potassium, increase water intake. Soya also contains some carbohydrates which are not readily digested by chickens which can also add to litter problems. However, modern breeds require higher protein levels in the feed to express their genetic potential for growth,” explains John. 

He adds, “The level and balance of protein have a real bearing on how wet the litter can become. But, there is a balance to be struck to avoid reducing growth rates. This is a matter which concerns performance, welfare and also economics.”

Nutritional prevention

John goes on to explain that the extent to which wet litter can translate into FPD can be affected by nutritional factors which affect the strength of the skin. “Trace elements such as zinc, and vitamins such as biotin can influence the integrity of the skin. Including higher levels of zinc and biotin in the diet may help ensure the skin is more resilient to damage from wet litter. It may be worth considering a higher trace mineral inclusion in the diet during the winter months when wet litter is more of a challenge,” advises John. ‘’Organic minerals can also positively affect skin development, and are more readily available, but these trace elements can be expensive and there are limits on the amount of zinc that can be legally added to poultry diets.”

In the last 20 years there have been major advances in the use of non-starch polysaccharide enzymes (NSP enzymes) in broiler diets. Their role in increasing the digestibility of the wheat element of the broiler diet - which leads to an improvement in the litter – has been key to NSP enzymes becoming a key component of any broiler diet.  

Gut health is another important consideration, explains John. “The UK poultry industry tends to use whole wheat in broiler feeds, which helps with gut condition. Encouraging the gizzard to work harder leads to a more favourable gut microflora and, hence an increase in the overall digestibility and gut health.” Using a coarse grist in the manufacture of the feed can also help, though this can make achieving good pellet quality more difficult.

Various additives such as prebiotics and probiotics can also improve gut health, and some coccidiostats also exert a beneficial influence. The use of these additives can also help reduce the need for prescription antibiotics in certain situations, details John. “By combining the use of these additives and a coarsely ground feed structure, it is possible to positively influence the gut health of the birds to aid digestion. Making sure that the levels of the major minerals (calcium, phosphorus and sodium) are correct will also help to reduce the incidence of wet litter and thus the chances of pododermatitis developing.”

Wider effect on the industry

David explains that there are several reasons why it is vital that the industry looks to reduce the occurrence of foot pad dermatitis. “Besides decreasing FPD to reduce the effects on the birds’ performance, and any associated welfare implications, it is important to consider the economic effects of FPD. There is still a considerable overseas market for chicken feet, and the main reason for abattoir rejections of feet is due to FPD lesions. There are also wider cost implications if birds are taking longer to reach their slaughter weights,” he adds.  

“The poultry industry needs to be fully aware of the foot pad burn issue and be conscious of the associated welfare, performance and cost implications. We need to come together to help reduce the incidence of pododermatitis by paying more attention to detail. Causal factors such as the environment, the litter, bird health and the nutrition can all be managed to reduce FPD,” concludes David.