Lymphocytes can vary in size from their smaller form to medium and large in size. The larger size is more common in ruminants. They have a high nucleus:cytoplasm ratio. The nucleus is round (free of segments) with coarse chromatin clumping. The cytoplasm is blue and often scant.

Lymphocytes can vary in size from their smaller form to medium and large in size. The larger size is more common in ruminants. They have a high nucleus:cytoplasm ratio. The nucleus is round (free of segments) with coarse chromatin clumping. The cytoplasm is blue and often scant.

Lymphocytes can vary in size from their smaller form to medium and large in size. The larger size is more common in ruminants. They have a high nucleus:cytoplasm ratio. The nucleus is round (free of segments) with coarse chromatin clumping. The cytoplasm is blue and often scant.

Neutrophils possess a densely-stained, clumped nucleus that develops more segments as it ages. The cytoplasm is clear to pale blue/grey with many small light pink granules. Also referred to as a polymorphonuclear leukocyte.

Neutrophils possess a densely-stained, clumped nucleus that develops more segments as it ages. The cytoplasm is clear to pale blue/grey with many small light pink granules. Also referred to as a polymorphonuclear leukocyte.

Neutrophils possess a densely-stained, clumped nucleus that develops more segments as it ages. The cytoplasm is clear to pale blue/grey with many small light pink granules. Also referred to as a polymorphonuclear leukocyte.

Neutrophils possess a densely-stained, clumped nucleus that develops more segments as it ages. The cytoplasm is clear to pale blue/grey with many small light pink granules. Also referred to as a polymorphonuclear leukocyte.

Monocytes are the largest of all leukocytes. It possesses a pleomorphic nucleus with fine, lacy chromatin that stains lighter than other leukocytes. There is abundant blue-grey cytoplasm which appears "foamy" and often contains vacuoles (bubbles).

Eosinophils are similar in size to the neutrophil. The nucleus is often band-shaped or limited to two or three lobes. The chromatin is clumped and stains dark, as in the neutrophil. The cytoplasm is light blue but is often obscured due to the presence of numerous medium-sized eosinophilic granules that stain orange-pink.