Fats are a key component of poultry feeds. Fats supply essential fatty acids, help the absorption of fat-soluble vitamins and are the most efficient source of energy.

Heated and oxidized fats contain peroxidation compounds that change the odor and palatability of the fat, while depressing feed intake and growth. Fats that contain unsaturated fatty acids are preferable in poultry feeds because they are more digestible; however, unsaturated fatty acids are also easily oxidized. Fish oil is very rich in unsaturated fatty acids, and soybean oil is richer than palm kernel oil.

Oxidized fats increase the risk of necrotic enteritis

The presence of oxidized fats in the feed leads to an oxidative imbalance that impairs gut health through several mechanisms of action:

• Oxidized fats lead to changes in the bacterial populations of the gut flora, resulting in increasing counts of Clostridium perfringens, the bacteria that causes necrotic enteritis, in the upper part of the digestive system. In the same way, the addition of animal fats like tallow or lard, even if their quality is good, favors the growth of Clostridium perfringens.

• The membrane of the intestinal epithelial cells contains high amounts of polyunsaturated fatty acids (PUFA). Oxidized fats lead to cell injury, breaking the epithelial barrier function. Furthermore, oxidized fats weaken the tight junctions, which are complexes of proteins located between the epithelial cells involved in the gut barrier function.  (More about the gut barrier here). The breakdown of the gut barrier allows Clostridium perfringens to reach the bloodstream and infect the liver.

• Oxidized fats impair the local digestive immunity, by disrupting the gut associated lymphoid tissue (GALT) and reducing the production of immune cells and immune proteins. A poor immune system is a predisposing factor for necrotic enteritis.

Prevention of the risks posed by oxidized fats

During feed manufacturing, it is key to select good quality fats and to add a suitable antioxidant that will neutralize the peroxidation compounds that are present in the lipids.

When acting on feed composition is not possible for the farmer, the addition of natural antioxidant such as PhytoShield© via drinking water is able to restore the redox balance in the gut epithelial cells, reinforcing the gut barrier and the local immune system.

On the other hand, the use of plant extracts with prebiotic and microbiocide properties (GrowthPlus© through feed or PlusProtect Digestive© through drinking water) will maintain and restore the balance of a healthy gut flora and at the same time prevent the overgrowth of Clostridium perfringens.