Pathology of toxoplasmosis in captive new world primates.

Clinical information was available for 32 of 33 New World primates with fatal toxoplasmosis, all of which were subjected to a variable number of pathological observations. Death without apparent clinical signs occurred in 43.7% of cases. The most common clinical findings were malaise (40.6%), dyspnoea (18.7%), hypothermia (15.6%) and a sero-sanguinous or foamy nasal discharge (12.5%). Nutritional status was good in 71.8%, average in 18.7% and poor in 9.4%. The most common post-mortem findings were pulmonary congestion (78.8%), pulmonary oedema (75.8%), splenomegaly (57.6%) and mesenteric lymphadenitis (54.6%). The most common histopathological findings were multifocal necrotic hepatitis (97%), lymphadenitis (95.4%), interstitial pneumonia (90.3%) and necrotic splenitis (71.4%). The gross post-mortem changes in cebids were more variable than those observed in callitrichids, a fact that may complicate the diagnosis of toxoplasmosis in cebids.