Mast cells in the pigeon olfactory bulb

Mast cells were present in the granule cell layer of the pigeon (Columba livia) olfactory bulb. They were found within the neural parenchyma, and although some mast cells were located near blood vessels, they were not seen in the intracerebral perivascular connective tissue. Although mast cells and blood basophils in this bird were quite similar ultrastructurally, there were several histochemical differences. The mast cells demonstrated histochemical evidence of glycogen and histidine, whereas the blood basophil was practically devoid of these substances.