Demonstration of the phagocytic activity of chicken thrombocytes using colloidal carbon.

Chicken thrombocytes showed marked phagocytosis of carbon particles in both in vivo and in vitro systems. Initially, in both systems, thrombocytes containing carbon particles tended to form clumps. In the later stages, however, clumping was less obvious in the in vivo system. In addition to the thrombocytes, monocytes also contained carbon particles but heterophils did not. The present findings suggest that thrombocytes play a useful role in helping to clear the blood of foreign materials.