Neospora and Sarcocystis Flashcards
Definitive host(s) of Neospora caninum?
dogs and coyotes
Main effect of Neospora in dogs?
fatal neuromuscular disease
Main effect of Neospora in cattle?
reproductive failure and abortion
Coccidia?
obligate intracellular parasite
Predominant route of Neospora transmission?
congenital
occurs in dogs, cattle, sheep, goats, pigs, horses, cats, mice, monkeys
Neospora pathogenesis
host cell destroyed by tachyzoites resulting in focal areas of necrosis, non-suppurative inflammation
Cattle Neosporosis
abortion/stillbirths, live calves may have other neuro problems or break the cycle and be free of infection
Dog Neosporosis
often subclinical, but main sign is progressive paralysis, beginning with the hindlimbs and working its way up, trouble swallowing (dysphagia)
Dog Neosporosis Age of Onset
young puppies below 6 months of age (most often 3-9 weeks)
Neospora Diagnosis
Antibodies in serum or CSF in dogs, fetal fluids in cattle
shedding of oocysts is sporadic and inconsistent
Treatment for Cattle Neosporosis
cull
Treatment for Dog Neosporosis
limited options (sulfonamides, pyrimethamine, clindamycin), older pups (>4months) respond better
Is sarcocystis a coccidian protozoa?
yes
How many species of Sarcocystis are there?
so damn many (hundreds)
Definitive host of sarcocystis?
dogs
Intermediate host of Sarcocystis
cattle, sheep, pig, horse
How are dogs infected with Sarcocystis?
they ingest an intermediate host (usually infected muscle tissues)
How are intermediate hosts infected with Sarcocystis?
they pick up oocysts in feces (fecal-oral)
Sarcocystis cruzi species?
cattle
Sarcocystis ariticanis and tenella species?
sheep
Sarcocystis porcifelis species?
pigs
Sarcocystis neurona species affected?
HORSES
Equine Protozoal Myeloencephalitis (EPM)
caused by Sarcocystis neurona, resulting in non-suppurative necrotizing lesions in spinal cord, brain, and meninges –> stumbling, dragging limbs, intermittent lameness, dysphagia, etc
Definitive host of Sarcocystis neurona?
POSSUMS, the adorable little devils pass oocysts in their feces
Distribution of Sarcocystis neurona?
the Americas; cases are still sporadic and many horses (30-50%) have antibodies
Diagnosis of Sarcocystis?
look for “packs” of cysts in muscle tissue, or multinucleate schizonts in endothelial cells; can also analyze Ab in CSF sample in horses; possum feces if known contact
Only approved drug for Sarcocystis treatment?
ponazuril! (Marquis)
After treatment, can horses relapse?
YES especially if initial treatment was of insufficient duration
