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Obtaining Highly Purified Toxoplasma gondii Oocysts by a Discontinuous Cesium Chloride Gradient
Published on: November 3, 2009
Ocular and encephalic toxoplasmosis in canaries
S M Williams1, R M Fulton, J A Render
1Department of Veterinary Pathology, College of Veterinary Medicine, Michigan State University, East Lansing 48824, USA.
Avian Diseases
|May 3, 2001
Summary
Toxoplasma gondii caused blindness and torticollis in canaries. Microscopic examination revealed protozoal lesions in the eyes and brains of affected birds, suggesting a potential feline source of infection.
Area of Science:
- Veterinary Pathology
- Parasitology
- Avian Medicine
Background:
- Toxoplasma gondii is an important protozoal pathogen affecting a wide range of hosts.
- Avian species are susceptible to toxoplasmosis, but ocular and neurological manifestations in canaries are not well-documented.
Observation:
- A flock of 15 common yellow canaries (Serinus canaria) experienced blindness and torticollis.
- Nine birds developed blindness over three months, and two birds showed torticollis.
- Microscopic examination revealed nonsuppurative chorioretinitis and T. gondii tachyzoites in the retina and subretinal space.
Findings:
- Toxoplasma gondii tachyzoites and tissue cysts (bradyzoites) were identified in the eyes and brains of affected canaries.
- Infected macrophages containing tachyzoites were prominent in the subretinal space.
- T. gondii was confirmed using transmission electron microscopy and indirect fluorescent antibody tests.
Implications:
- This case highlights the potential for T. gondii to cause significant pathology in canaries.
- A stray cat accessing bird feed was hypothesized as the infection source, emphasizing biosecurity measures.
- Understanding these lesions aids in diagnosing and managing toxoplasmosis in pet birds.
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