Heinz body anaemia associated with onion (Allium cepa) toxicosis in a flock of sheep

Onion (Allium cepa) toxicosis was diagnosed in a flock of local breed sheep, which had grazed daily on onion fields for 1 month. Two ewes died, four aborted and many showed clinical signs of toxicosis including pale mucous membranes, weakness and poor appetite. Haematology of 12 ewes revealed low PCV, erythrocyte number and haemoglobin, Heinz bodies in erythrocytes, polychromasia and mild leukocytosis. In those animals that died, there was haemoglobinuric nephrosis with haemosiderin deposition in tubular cells and centrilobular necrosis of liver. Onion feeding was discontinued and haematinics were used for treatment of the affected animals.