Coccidiosis

Coccidiosis is a disease of animals kept under crowded conditions and caused by a protozoan parasite, Eimeria spp. Intensive, damp, and dirty conditions such as many breeding establishments predispose to coccidiosis.

About the parasite
Coccidia strains are highly host- and site-specific, and infection occurs by ingestion of oocysts passed in the feces of infected rabbits. The oocysts require 48 to 70 hours outside the host to produce spores, are very resistant in the environment, and can survive for years. They can be spread through feed, soil, and any other substance that is capable of carrying infectious organisms (e.g. blankets, clothing, skin).

Ingestion of the oocyst releases sporozoites into the small intestine after the oocyst have been broken down by digestive enzymes. The sporozoites invade cells and cause tissue damage as they complete their complex life cycle.

As many as 14 species of Eimeria have been described in the rabbit. All but one species are found in the small intestine, cecum, or colon and cause intestinal coccidiosis. The species Eimeria stiedae inhabites the liver and causes hepatic coccidiosis.

There is no cross-immunity between the different species of Eimeria.

Symptoms
The disease is often asymptomatic, but signs of the parasite include the following:


 * Watery-to-mucoid, sometimes blood-tinged, diarrhea. The diarrhea may be intermittent.
 * Weakness, lethargy, dehydration, and weight loss with heavy infections, especially in young rabbits.
 * Can cause the inversion of the intestine (intussusception) and even death.
 * With hepatic (liver) involvement, may see anorexia, weight loss, depression, abdominal enlargement and pain, diarrhea, or acute death.

Causes

 * Infected rabbits contaminating the environment.
 * Poor sanitation.

Stress, debility, and concurrent disease can predispose older animals to infection.