Refractory phagocytosis by chicken thrombocytes during aflatoxicosis.

The percentage phagocytosis of chicken thrombocytes was insensitive to dietary aflatoxin (10 microgram/g diet) while the mean phagocytosis was slightly but significantly (P less than .05) reduced by 5 or 10 microgram/g but not lower levels. Thrombocytic phagocytosis was dependent on a heat sensitive serum factor which is not affected during aflatoxicosis. These findings contrast with reports that other phagocytic types such as heterophils, macrophages, and monocytes are sensitive to low levels (e.g., .625 microgram/g) of dietary aflatoxin.