PHF Flashcards
Organism
Neorickettsia risticii
Invades
macrophages and epithelial cells of intestine
Months of concern
May - November
Organism present
in feces
Intermediate hosts
snails, mayflies, dragonflies, caddisflies, damselflies
Can be contracted by
drinking infected water
eating infected insect
skin penetration
After infection, N risticii infects
blood monocytes
GI tract
lesions
Diarrhea related to
loss of epithelial cells
Diarrhea/loss of epithelial cells causes
reduced luminal absorption of electrolytes and increased water losses
Recovered horses are immune for
at least 20 months
Incubation period
1-3 weeks
Risk factors
proximity to water
time outside
insect population
Clinical signs
Depression anorexia biphasic fever decreased intestinal sounds moderate to severe diarrhea abdominal discomfort Possible: severe toxemia dehydration cardiac compromise congested mucosal membranes
Increases risk for
laminitis
Mortality Rate
5-30% (associated with toxemia and laminitis)
Diagnosis
isolation of N risticii from blood or feces
differential diagnosis
Treatment: administer
IV oxytetracycline BID (5 days)
Fluids (hypovolemia/shock)
Banamine (fever/discomfort/endotoxemia)
Prevention
Vaccine is of questionable usefulness
Limit risk factors
