Toxoplasma gondii ( T. gondii ), the causative agent of toxoplasmosis, is an opportunistic, zoonotic, obligate intracellular protozoan parasite that has the capacity to infect all endotherms including birds. While infection does not cause clinical illness in most animal species, it can cause acute life-threatening disease in some.
In others (particularly sheep and goats, but occasionally pigs), it multiplies in the placenta and foetus to cause reproductive disease during pregnancy.