Ruminants Exam 1 Flashcards
What is ETEC?
Enterotoxigenic E. coli
ETEC
Major cause of early calf mortality. Hypersecretory diarrhea. STa is most important toxin calves. -heat stabie toxin -rapid onset.
ETEC S/S
1-7 days of age, but up to 3 weeks with mixed infections.
Mild to severe diarrhea and dehydration.
If severe, dehydration and weakness can precede diarrhea.
ETEC Lab data
Metabolic acidosis - HCO3 loss can be extreme.
Lyte derangments: decreased Na, Cl, Glu. ^K.
CBC - hemoconcentration, +/- leukopenia
Alkaline fecal pH
ETEC Dx
Age
S/S
Lab data
Fecal iso of E. coli with appropriate fimbrial antigens — rarely done.
ETEC prevention
Clean environment
Adequate colostral transfer
Commercial bacterin to dry cows
Monoclonal AB product after birth
Rotavirus gen info
Reoviridae family
Group A rotavirus - calves, foals
Short incubation 12-24h
Calves <2wk are at greatest risk
Severity of signs related to age, <5d most severe.
Mixed infection with E. coli or crypto common.
Rotavirus pathophysiology
SI only
Localized to villous tips
Enzyme deficiencies - lactase.
Causes net secretion
Rotavirus S/S
Highly variable Most severe in calves <5d Lethargy, dehydration Reduced appetite Low-grade fever Diarrhea
Rotavirus Dx
EM
ELISA
Latex agglutination
Fecal pH tends to be ACIDIC <6.5
Rotavirus prevention
Highly infectious and contagious
Phenol-based disinfectant
Vx of dry cows
Ensure adequate passive transfer
Coronavirus gen info
Older calves 7-21d, but range 1-90d.
SI and colon.
Epithelial cells of jejenal villi infected, crypt cells spared, villous blunting
Mortality 1-25%, note that this is greater than rotavirus
Coronavirus S/S
Depression, reluctance to nurse Diarrhea severe and watery Dehydration Feces may contain clear mucus Signs typically last >7d
Coronavirus Dx
EM/ELISA on feces
FA test of tissues
Shed by healthy adult cattle and calves
Coronavirus prevention
Environmental management
Vx of dry cows
Ensure adequate colostral transfer
Commercial oral AB products at birth
