Salmonella Flashcards
Causes ________ disease
enteric or systemic
2 species
S. enterica
S. bongori
host adapted salmonella causes
systemic disease
non-host adapted salmonella causes
colitis and diarrhea
can produce systemic disease in neonates
Salmonella is gram
negative
Source of infection
difficult to identify
Route of infection
oral
Outbreaks
in hospitalized animals
Horses shed more in ______ than ______
summer, winter
Can persist in fecal matter for
months - years
salmonella and commercial feed
up to 40% is positive
none is certified salmonella free
pelleting may destroy
Other sources of contamination
bird and rodent feces
pasture contamination
What about the horse resists salmonella?
Normal gut flora and motility
Risk factors
foals
stress
deworming
high temperatures
Infection depends on
bacterial load
salmonella invades the
intestinal epithelial cells
Causes:
large inflammatory respons
Inflammation and epithelial necrosis result in
loss of serum protein into the lumen, leading to hypoproteinemia
hypovolemia
decrease in the volume of blood in the body
Endotoxins are released when
microbes die or divide
leukopenia
decrease in the number of white blood cells
septicemia
foals more susceptible
One challenge of salmonella is that there are
silent carriers
Clinical signs of mild infection
fever
reduced feed intake
loose stool
differential diagnosis with mild respiratory disease
Clinical signs of severe infection
acute diarrhea colic anorexia fluid / electrolyte losses dehydration >liver and kidney damage, laminitis
Challenge of diagnosis
false-positives and false-negatives
Testing
3 negative tests
Antibiotic administration
controversial
Diagnosis
bacterial isolation
fecal culture
difficult
Administer?
Banamine (anti-endotoxic effect)
Fluids
Nursing care
Prevention of salmonella
quarantine new arrivals or those coming from hospital cleanliness avoid overcrowding pelleted feeds control pest access to horse housing
