EPIZOOTIC DISSEMINATED TOXOPLASMOSIS IN CAPTIVE SLENDER-TAILED MEERKATS (SURICATA-SURICATTA)

Fatal disseminated toxoplasmosis was diagnosed in seven captive slende r-tailed meerkats (Suricata suricatta) according to clinicopathologic findings and immunohistochemistry. Five of nine meerkats died during a n outbreak in late 1994. These included four kits (2.5 to 4.5 months o ld) and a 4-year-old meerkat. Two other meerkats, both adults, died in 1992 and 1995. Respiratory insufficiency (4/7) and incoordination (3/ 7) were the most consistent clinical signs, although two of seven meer kats died unexpectedly. At necropsy, the lungs were reddened and nonco llapsed (6/7), and had multiple pale round foci (4/7). Yellow foci of necrosis in mesenteric lymph nodes (4/7), splenomegaly (3/7), and hydr opericardium (3/7) were other common gross findings. Microscopically, interstitial pneumonia was present in all seven meerkats, being acute to subacute in six of them Type 2 pneumocyte hyperplasia, aggregates o f foamy macrophages, and giant cells were consistently seen. Multifoca l to locally extensive necrosis of mesenteric lymph nodes (4/7), mild to severe multifocal necrotizing hepatitis (5/6), and mild nonsuppurat ive encephalitis (4/6) were also seen. Toxoplasma-like organisms were consistently associated with these lesions and were stained by the avi din biotin peroxidase procedure with an antiserum that does not cross- react with Neospora caninum. Meerkats were most likely infected after an oral, primary exposure to Toxoplasma. Several observations indicate that meerkats may be highly susceptible to toxoplasmosis.