SYSTEMIC MASTOCYTOSIS IN A GOAT

Systemic mastocytosis was diagnosed in a 4-year-old, female Nubian goa t. Clinically, the animal was depressed and had severe macrocytic hypo chromic anemia and leukopenia. Postmortem examination revealed neoplas tic mast cells invading the heart, lung, liver, spleen, lymph nodes, a nd bone marrow. Eosinophils were frequently admired with infiltrating mast cells in all organs. Using routine light microscopy, histochemist ry, and transmission electron microscopy, metachromatic and periodic a cid-Schiff-positive granules were identified within the cytoplasm of n eoplastic mast cells. Erythrophagocytosis was observed in some neoplas tic cells, although its contribution to the anemia was not clear. This report represents the first description of mast cell neoplasia in the goat.