Monocytes of animals
Monocytes of animals are the largest of WBCs, characterized by kidney or bean shaped nucleus.
Monocytes are actively motile, pinocytic and also highly phagocytic, which may migrate into the tissue spaces and become macrophages. These cells are much more powerful phagocytes than neutrophils by their ability to engulf much large sized particles, necrotic tissues and more number of microorganisms.
Monocytes leave the blood and are attracted to the tissues by chemotaxis and lymphokines and they become macrophages, example reticular cells of lymph nodes, spleen, bone marrow and Kupffer cells of the liver sinuses.
Abnormalities of Monocytes
Monocytosis
Monocytosis condition indicates increased number of monocytes in the circulation and is seen in hematological malignancies, endocarditis, typhoid, TB, brucellosis and prolonged blood parasitic infections. Eg: trypanosomiasis.