Necrotic Enteritis of Poultry

Necrotic enteritis (NE) produced by Clostridium perfringens is the most severe clostridial enteric disease of poultry, and it is estimated that worldwide NE costs the poultry industry 2 billion dollars per year. The disease occurs in two forms: acute and chronic. The acute form is associated with loss due to increased mortality rates at around 3-4 weeks of age, but it is the chronic or subclinical form that results in severe economic loss due to reduced weight gain and less efficient feed conversion. The subclinical form causes the greatest production loss, as it often goes undetected. This chapter discusses the epidemology, etiology and pathogenesis, host response, predisposing factors, clinical signs, gross changes, and microscopic changes of the disease. The development of direct PCR screening, DNA sequencing, and real-time PCR assays directly from the intestinal tract of birds without cultivation may significantly speed up the diagnostic process.