Coccidia Infections in Poultry

Coccidiosis is a parasitic disease caused by the development and multiplication of coccidia in the epithelial cells of the intestine.

Eimeria infections are ubiquitous; they are found wherever chickens or turkeys are reared (traditional, industrial, label or organic/bio farms).

Their survival is assured by a highly resistant form of transmission - the oocyst - which may survive for several months in the environment.

The disease is the result of a breakdown in the balance between:

• The parasites: their number, their pathogenicity and their ability to promote immunity in the host.
• The host: its susceptibility, including its protection by anticoccidials, and its ability to regenerate from the damage caused by the parasite. Chickens selected for their zootechnical performance are particularly sensitive to coccidia.
• The environment: intensive rearing particularly predisposes conditions for coccidiosis.
  Despite hygiene measures, drug prophylaxis and the recent development of attenuated live vaccines, coccidia remain a major problem in poultry rearing.

The global cost of the prevention of coccidia in chicken is estimated at USD 300 million a year (Diseases of Poultry 11 ed, 2003, Y .M. Saif).