Neutrophils

Neutrophils are granulocytic white blood cells (WBC with granules). They have a two to five segmented nucleus, each part joined by a thin strand of chromatin. Often there is a "hole" that appears in the nucleus because of the segments (this is known as the Barr body, an area where there WAS part of a nucleus but the genes were inactivated at the birth of the cell). The cytoplasm is difficult to see because it is "neutral" with the background it sits in. This makes the granules hard to see. Sometimes the nucleus doesn't have segments, and this is called a Band neutrophil where the nucleus takes a horseshoe shape. This happens because the cell was released from the bone marrow before it had a chance to fully mature. If you see enough of these unsegmented neutrophil nuclei, the body is most likely in hyper production of neutrophils due to some foreign invader in the blood or ill health of the animal.