Aflatoxicosis is a fungal borne toxicosis that may affect almost all species of livestock in India as well as abroad. Aflatoxins are major class of mycotoxins produced primarily by Aspergillus flavus i.e. most common grain mold fungi. The fungus grows on carbohydrate rich feeds such as peanuts, cottonseed, corn, sorghum and cereal grains when they are stored in hot conditions without adequate drying and aeration. Aflatoxin M1 found in milk of dairy cattle is the metabolite of Aflatoxin B1 that occurs in feed materials. Aflatoxicosis is a problem in livestock, most notably swine and cattle. Gross lesions include hepatic enlargement, congestion, yellow discoloration, and friability; petechiae or more generalized hemorrhage; and edema and ecchymotic or petechial hemorrhages of the gall bladder. Cattle are more resistant than pigs, but the typical lesions of aflatoxicosis, as described above, can be found following exposure. Fibrosis and bile duct proliferation may be extensive and found together with fibrotic veno-occlusion of the central veins. Sheep are resistant to aflatoxin.