The brain of a 7-year-old Quarter horse mare was sent to the…
The brain of a 7-year-old Quarter horse mare was sent to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for histopathology. This horse was reported to have clinical neurological signs. Histology showed these protozoal schizonts (arrows) intermingled among inflammatory cells, prompting the diagnosis of Equine Protozoal Myeloencephalitis (EPM) for this horse. Which protozoa is responsible for this disease?