Fig 4. Thin blood smears assessed by light microscopy.

Blood smear images were presented from one animal each for day 42 post infection challenge from all three experimental group animals. The images were collected following viewing with a 40x magnification. A. marginale inclusions are shown by black arrows (observed only in infection controls and WCAV animals; panels A and B), but not in MLAV animals (C). The A. marginale inclusions (identified with arrowhead lines) and anisocytosis are evident in both non-vaccinated infection controls WCAV vaccinees, but not in MLAV vaccinees. The length bars on the bottom left corner of each panel represent 50 microns.