Necrotic enteritis has been estimated to affect up to 40 percent of commercial broiler flocks and is believed to cost the industry roughly 5 cents per broiler in the United States. On average, necrotic enteritis negatively impacts the global poultry industry by over $2 billion every year.

In the past, sub-therapeutic levels of antibiotics incorporated into poultry feed played an important role in the prevention of necrotic enteritis. Antibiotics and other antibiotic growth promoters modify the microflora populations in the intestine, minimizing the chance for coccidiosis and necrotic enteritis development. However, many countries today have banned the use of antibiotics in animal feed due to consumer concerns of the development of antibiotic resistant bacteria. Even in countries where still legal, large corporations are discontinuing antibiotic use due to this consumer pressure.

The withdrawal of antibiotic use in feed is one of many predisposing factors for necrotic enteritis. This decrease in antibiotic use has resulted in negative impacts on bird average daily gains and feed conversion ratios (FCR), as well as an increase in the number of confirmed cases of necrotic enteritis. Consequently, this has resulted in an increase in the usage of therapeutic antibiotics to treat necrotic enteritis after it has occurred in the animal.

Necrotic enteritis will typically last in a flock for five to ten days and can cause mortality rates up to 50 percent. Dead birds appear dehydrated and produce a foul odor. The jejunum and ileum of the small intestine are typically covered in macroscopic lesions, sometimes extending to the duodenum or ceca. The small intestine is usually friable and ballooned with gas, and contains a foul-smelling brown liquid. Also, the intestinal mucosa may be covered in a tan/yellow pseudo-membrane.

There are several existing predisposing factors for necrotic enteritis which need to be addressed in order to understand ways the disease can be prevented. These predisposing factors include disease exposure, individual feed ingredients, environmental stress and a decrease in the use of in-feed antibiotics.

Protease: Optimizing protein digestibility

The addition of a high-quality protease, such as CIBENZA® DP100 from Novus International, allows for maximum flexibility in dietary formulations, and optimizes dietary energy and protein digestibility. CIBENZA DP100 is an intrinsically heat-stable, broad-spectrum protease that complements animals’ endogenous enzymes to hydrolyze less-digestible proteins in animal feeds. Research has demonstrated CIBENZA DP100 enhances dietary protein digestibility, supports animal performance and reduces feed cost when compared to other protease sources.

Inclusion of CIBENZA DP100 improves digestion of protein in feed ingredients, thereby allowing lower inclusion of total protein when formulating poultry diets. Secondly, due to the increased digestion of protein, a lesser amount of undigested protein is passed into the hind gut. This consequently reduces the proteolytic fermentation that can lead to formation of potentially toxic end products, such as biogenic amines, phenolic components, ammonia and other volatile components, which are detrimental to the health and production performance of poultry. As CIBENZA DP100 is effective in reducing the amount of undigested protein, it leaves less protein available for C. perfringens growth in the gut, which may lead to a lower incidence of necrotic enteritis (Figure 2).