Coccidia

Coccidiosis in Rabbits (Eimeria spp.)

Coccidiosis is a protozoal disease caused by Eimeria species in rabbits. It affects primarily the intestinal tract (intestinal coccidiosis) or liver (hepatic coccidiosis) and is most common in young or immunocompromised animals.

Etiology (cause)

Coccidiosis is caused by infection with protozoan parasites of the genus Eimeria. The disease is transmitted via ingestion of sporulated oocysts present in contaminated food, water, or environment.

• Common species: Eimeria stiedae (hepatic), Eimeria perforans, Eimeria magna, Eimeria media (intestinal)
• Pathophysiology: After ingestion, sporozoites invade epithelial cells of the intestines or liver, multiply asexually and sexually, causing cellular destruction, inflammation, and in severe cases, systemic disease.
• Source: Coccidia of rabbit: A review. Folia Parasitologica. 2009;56(3):153–166. doi:[10.14411/fp.2009.019](https://doi.org/10.14411/fp.2009.019)

Clinical Signs

Signs depend on the species affected and severity of infection:

• Depression and lethargy
• Anorexia
• Anemia and pale mucous membranes
• Signs of pain, e.g., hunching or abdominal discomfort
• Blood or mucus in feces (intestinal coccidiosis)
• Poor coat condition
• Dehydration
• Weight loss or poor growth
• Severe intestinal infection: intussusception, convulsions, paralysis, or death
• Severe hepatic infection: weakness, liver and bile duct damage, coma

Treatment, Prevention, and Control

• **Drug class:** Antiprotozoal / Anticoccidial agent
• **First-line treatment:** Toltrazuril (Baycox®) is the drug of choice in advanced or clinical cases. It eradicates Eimeria parasites.
• **Dosage:** 20 mg/kg orally, concentration 5% (50 mg/mL), approximately 0.18 mL per pound. Administer with or without food.
• **Precautions:** Avoid direct contact; wear gloves. Monitor for gastrointestinal upset. Contraindicated in patients allergic to toltrazuril or related compounds (e.g., ponazuril). Not approved in the US, may be legally imported by veterinarians.

• • Supportive care:** Hydration, electrolyte support, and nutritional support for severely affected rabbits.

• • Prevention and control:**
• Maintain clean, dry housing and feeding areas
• Minimize overcrowding
• Remove feces frequently to reduce environmental oocyst load
• Monitor young or immunocompromised rabbits closely

• • References for treatment and pharmacokinetics:**
• Toltrazuril treatment against coccidiosis: [PubMed 25286655](https://pubmed.ncbi.nlm.nih.gov/25286655/)
• Amprolium and toltrazuril efficacy: [PubMed 29163644](https://pubmed.ncbi.nlm.nih.gov/29163644/)
• Pharmacokinetics in rabbits: [PubMed 20083354](https://pubmed.ncbi.nlm.nih.gov/20083354/)
• Eimeria stiedae experimental infection: [PubMed 18321485](https://pubmed.ncbi.nlm.nih.gov/18321485/)
• Novel oil-based suspension study: [PubMed 34597913](https://pubmed.ncbi.nlm.nih.gov/34597913/)
• Nanomicelle delivery system: [PubMed 29289823](https://pubmed.ncbi.nlm.nih.gov/29289823/)
• Comparison with sulphadimethoxine: [PubMed 20729515](https://pubmed.ncbi.nlm.nih.gov/20729515/)
• Antibody detection of toltrazuril: [PubMed 12790197](https://pubmed.ncbi.nlm.nih.gov/12790197/)
• Improved bioavailability study: [PubMed 20860101](https://pubmed.ncbi.nlm.nih.gov/20860101/)
• Herbal formulations in subclinical coccidiosis: [PubMed 24930248](https://pubmed.ncbi.nlm.nih.gov/24930248/)

References

• Coccidia of rabbit: A review. Folia Parasitologica. 2009;56(3):153–166. doi:[10.14411/fp.2009.019](https://doi.org/10.14411/fp.2009.019)
• Baycox® Toltrazuril Data Sheet: [MedChemExpress](https://file.medchemexpress.com/batch_PDF/HY-B0175/Toltrazuril-DataSheet-MedChemExpress.pdf)
• VMG-Toltrazuril 2019: [PDF](https://cdn.brief.vet/web-files/PVD/drupal-uploads/files/VMG-Toltrazuril-2019-01-30-0421.pdf)
• Baycox 5% Oral Suspension Info: [Drugs.com](https://www.drugs.com/vet/baycox-toltrazuril-5-oral-suspension-can.html)
• Dosage calculator: [vgr1.com](https://www.vgr1.com/toltrazuril/)