Equine Parasites: Protozoa Flashcards
How would you classify Eimeria leukarti?
Protozoan parasite
Describe Eimeria leukarti eggs.
Oval oocyst 80-60 Mm
Thick and dark colored
Distinct micropyle
Shell can come off
What is the PPP of Eimeria leukarti?
15 days
What are the 3 phases of Eimeria leukarti life cycle?
Sporulation
Asexual Reproduction
Sexual Reproduction
Infection and schizogony refer to what phase of the Eimeria leukarti life cycle?
Asexual Reproduction
Gametogony and oocyst formation refer to what phase of the Eimeria leukarti life cycle?
Sexual Reproduction
What is the site of infection for Eimeria leukarti?
Small Intestine
What pathogenesis and lesions are associated with Eimeria leukarti protozoan parasite?
Inflammatory changes in mucosa
Disruption of villous architecture
What are the clinical signs of Eimeria leukarti?
Intermittant diarrhea
Who is most susceptible to contracting Eimeria leukarti?
Foals
How is Eimeria leukarti diagnosed?
Sugar flotation or specific sedimentation
How is Eimeria leukarti treated?
Antiprotozoals like sulpha-drugs
What is the common name of Sarcocystis neurona?
Equine Protozoal Myeloencephalitis (EPM)
What is the definitive host of Sarcocystis neurona/EPM?
Opossum
What is the intermediate host of Sarcocystis neurona/EPM?
Cats, skunks, raccoons
What is the accidental/aberrant host of Sarcocystis neurona/EPM?
EQUINE
What happens in the normal life cycle of Sarcocystis neurona (when on its proper DH)?
Gametogony in opossum (DH)
Shizogony in IH with bradyzoites in muscles of IH
What happens when Sarcocystis neurona/EPM infects an accidental/aberrant host?
Schizonts in horse’s NEURONS, not in muscle cells
Where is Sarcocystis neurona/EPM found in the US majorly?
Oklahoma! Also in CA and FL
Who does Sarcocystis neurona/EPM affect most?
Younger horses
Is Sarcocystis neurona/EPM pathogenic?
Non-pathogenic in final host, pathogenic in accidental host
What pathogenesis does Sarcocystis neurona/EPM cause in the accidental host (horse)?
3rd stage schizogony in neurons instead of muscle tissue
What are clinical signs associated with Sarcocystis neurona/EPM in horse?
Progressive debilitation of of CNS, brain, brainstem, and spinal cord Lameness Seizures Difficulty standing, walking, swallowing Ataxia Atrophy of muscles
What is the most commonly diagnosed infectious equine neurologic disease in North America?
Sarcocystis neurona/EPM
How is Sarcocystis neurona/EPM prevented?
Prevent opossums from defecating where horses eat
How is Sarcocystis neurona/EPM treated?
Antiprotozoals, but CNS damage that has already occurred will persist
How successful is Sarcocystis neurona/EPM treatment?
70-75%
Are sarcocysts associated with Sarcocystis neurona/EPM?
NO
Where would you find schizonts and merozoites in the horse?
Confined to the brain and spinal cord
