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Toxoplasmosis in domestic animals |
In addition to serving as a source of infection, cats can also
develop clinical toxoplasmosis themselves, as can dogs and other
domestic animals.
In cats:
Infection can affect virtually any organ in the body, so clinical
signs are varied:
- fever of unknown origin
- uveitis/chorioretinitis (keratic precipitates, aqueous flare,
retinal detachment) and associated intraocular disease
- Ocular disease can present in the absence of other systemic
signs of infection.
- encephalitis (Click
here for a photo of a scan of a cat with Toxoplasma encephalitis)
- polymyositis
- pneumonitis
- hepatitis
- "fading kitten syndrome" following transplacental
infection
- In one experimental study (Dubey, Lappin and Thulliez, 1995),
most kittens born to queens infected during pregnancy died within
24 hours of birth.
Infection and disease in cats appear to be more common in FIV
(+) cats, but not necessarily in FeLV (+) cats.
In dogs:
Clinical disease is less common than in cats, but can be manifest
as:
- severe, rapidly fatal systemic disease involving the respiratory
and gastrointestinal tracts
- meningomyeloencephalitis
- polymyositis
- Ocular disease occurs much less commonly in dogs than in
cats.
In other domestic animals:
- The most important manifestation of T. gondii infection
in farm animals is abortion in sheep and goats (very rarely cattle).
- Infection in non-pregnant ruminants and horses is generally
asymptomatic, but uveitis/chorioretinitis may occur.
