Necrotic enteritis (NE) is a life-threatening gastrointestinal disease of chickens. The disease is caused by the bacterium, Clostridium perfringens
. C. perfringens
is a Gram-positive, anaerobic, spore-forming pathogenic bacterium. It is commonly found in the intestinal tract of most animal species and humans, insects, soil, marine sediment, and decaying vegetation.
NE occurs when large numbers of C. perfringens
grow in the intestines, and secrete toxins. These toxins cause necrosis of the intestines, hemorrhaging, perforation of the intestine, and eventual death from septic shock. It is similar to Pig-bel Syndrome (enteritis necroticans) in humans, which is caused by the same bacteria.
The disease usually occurs in chickens living in unhygienic environmental conditions. Outbreaks are sporadic and the clinical illness of NE is short, with birds dying within a day of when initial clinical signs are first observed.
Risk Factors for NE
Some of the factors identified to increase the risk of NE in chickens include:
- Rough handling and abuse by farm workers.
- Mycotoxins: Chronic consumption of deoxynivalenol (DON) mycotoxins, which are a frequent contaminate of poultry feeds.
- Poor sanitary practices
- Protein-deficient diet
- Concurrent infection with the Ascaris intestinal parasite, which produces a trypsin inhibitor.
- Diet with high levels of non-starch polysaccharides, fishmeal, or trypsin inhibitors (sweet potatoes).
- Sporadic feasts of meat (after long periods of a protein-deficient diet)
Any factor that causes increased stress can suppress the chicken's immune system and offset the balance of flora in their gastrointestinal system, resulting in high levels of C. perfringens
NE can be diagnosed using a simple fecal test, in which the feces is sent off to diagnostic laboratory where it is tested specifically for the presence of the toxins produced by the C. perfringens
bacterium. These include:
- C. perfringens screen - Test consists of an anaerobe culture of the feces or intestinal loop. Results usually take 2-3 days. C. perfringens toxin typing Toxin detection : - Procedure conducted using an ELISA or PCR taken from feces or intestinal loop. Results usually take 2-8 days.