Protozoal

Question 1

Toxoplasma spp.

Answer 1

4-6 um long by ~2 um wide spindle to crescent shaped zoites with pale cytoplasm and a round, eosinophilic pericentral nucleus.

Question 2

Neospora/Hammondia/Isospora/Sarcocystis

Answer 2

5-9 um long by 2 um wide piriform to elliptical zoites containing a small, round, eosinophilic pericentral nucleus.

Question 3

Leishmania

Answer 3

2-5 um by 1.5-2 um wide, oval amastigotes with a thin outer membrane surrounding a small area of clear cytoplasm along with a light purple, eccentric, oval shaped nucleus and a smal,l deeply basophlic rod shaped kinetoplast oriented perpendicular to the long axis of the nucleus and typically placed on the side of the nucleus with the greater amount of cytoplasm.

Question 4

Cytauxzoon

Answer 4

Piroplasms are small, 1-1.5 um signet ring structures found within RBCs; Schizonts found in giant macrophages w/in the tissue (and rarely on blood smears) contain a multitude of developing merozoites. Merozoites will may appear as small deeply basophlic bodies, or larger light purple lobulated globules.