Coccidiosis

Coccidiosis
Classification and external resources

Coccidiosis is a disease caused by protozoan parasites of the phylum Apicomplexa, primarily affecting the intestinal tract of animals. It is a significant disease in poultry, cattle, and other livestock, as well as in pets such as dogs and cats. The disease is characterized by diarrhea, which can lead to severe dehydration and even death if not treated promptly.

Etiology

Coccidiosis is caused by infection with species of the genera Eimeria and Isospora. These parasites are obligate intracellular organisms that undergo complex life cycles involving both asexual and sexual reproduction. The oocysts, which are the infective stage, are shed in the feces of infected animals and can survive in the environment for extended periods.

Epidemiology

Coccidiosis is prevalent worldwide and can affect a wide range of animal species. The disease is most commonly seen in young animals, as they have not yet developed immunity to the parasites. Factors such as overcrowding, poor sanitation, and stress can increase the risk of outbreaks.

Pathogenesis

Once ingested, the oocysts release sporozoites in the host's intestine. These sporozoites invade the intestinal epithelial cells, where they undergo asexual reproduction to form merozoites. The merozoites then invade new cells, continuing the cycle. Eventually, sexual reproduction occurs, leading to the formation of new oocysts that are shed in the feces.

The destruction of intestinal cells by the parasites leads to the clinical signs of coccidiosis, including diarrhea, weight loss, and poor growth. In severe cases, the damage to the intestinal lining can result in hemorrhage and death.

Clinical Signs

The clinical signs of coccidiosis vary depending on the species of parasite and the host. Common signs include:

• Diarrhea, which may be bloody
• Weight loss
• Dehydration
• Lethargy
• Reduced feed intake

Diagnosis

Diagnosis of coccidiosis is typically based on clinical signs and the detection of oocysts in fecal samples. Microscopic examination of feces can reveal the presence of oocysts, and molecular techniques such as PCR can be used for species identification.

Treatment

Treatment of coccidiosis involves the use of anticoccidial drugs, such as sulfonamides, amprolium, and toltrazuril. Supportive care, including fluid therapy, may be necessary in severe cases to address dehydration and electrolyte imbalances.

Prevention

Preventive measures are crucial in managing coccidiosis, especially in intensive farming systems. These include:

• Maintaining good hygiene and sanitation
• Reducing stress and overcrowding
• Implementing biosecurity measures
• Vaccination, where available

See Also

• Protozoan infections
• Veterinary parasitology

References

• Smith, M. C., & Sherman, D. M. (2009). Goat Medicine. Wiley-Blackwell.
• Taylor, M. A., Coop, R. L., & Wall, R. L. (2015). Veterinary Parasitology. Wiley-Blackwell.

External Links

• Merck Veterinary Manual: Coccidiosis