Calf Diarrhea Flashcards
T or F, the specific agent causing scours in calves is very important to determine to solve the problem
False! specific agent is less important than risk factor triggers
what are the 3 aspects of the epidemiology of neonatal calf diarrhea?
pathogen, host, environment
true or false: calf scours is NEVER an individual animal problem
true! treating an individual and not asking about the rest of the herd is malpractice
list some causes of diarrhea in calves (there are a ton of these bestie just do your best)
ETEC (K99) or other E coli
salmonella
clostridium perfringens type C
campylobacter jejuni
rotavirus
coronavirus
totavirus
cryptosporidium
eimeria
giardia
yeast
nutritional
what exactly is nutritional scours?
- when the calf receives poor quality milk replacer or inappropriate replacer mixing
- if there’s sudden dietary changes
- over feeding
true or false: calves with nutritional scours have systemic signs
false, they should not be systemic, should be bright and alert, and should resolve in a few days
the most important pathogen causing diarrhea in calves less than 5 days old is ______
enterotoxigenic E coli (ETEC)
most common strain is F5/K99
why is it important to find virulence factors to confirm a diagnosis of ETEC?
because E coli is prevalent in fecal culture, but we don’t know if its specifically F5/K99, so we need to make sure! If a test comes back positive for E coli but we dont know the specific E coli, it may not actually be what is causing the diarrhea
how does a calf usually get ETEC? pathogenesis?
ingested from the environment, attaches to the intestinal epithelium and really likes the ileum, then spreads to the duodenum and produces toxins causing a secretory diarrhea. EPITHELIUM REMAINS IN TACT
_____ typically infects 5-15 day old calves, but can infect younger and older ones too
rotavirus
pathogenesis of rotavirus infection causing diarrhea
adult cattle and older calves excrete the virus into the environment, the calf ingests the virus from the environment, virus kills the villous enterocytes and reduces absorptive surface area causing a malabsorptive diarrhea. also toxin induced secretory diarrhea
rotavirus targets the ________ , which means ____
mature villar cells
the developing/immature cells quickly replace and there is minimal epithelial damage and it quikcly resolves
true or false: rotavirus often results in coinfection
true
clinical signs of rotavirus
profuse watery diarrhea, dehydration, depression, weakness, hypoglycemia
high morbidity and low mortality
which virus is similar to rotavirus but infects slightly older calves and causes more severe disease?
coronavirus
which virus causes winter dysentery in adults associated with BRD?
coronavirus
coronavirus typically infects calves that are how old
5-21 days old
coronavirus targets what cells?
crypt AND villous enterocytes, which means worse maldigestive and malabsorptive diarrhea
crypt loss=prolonged illness and more severe acidosis and dehydration
which has higher mortality, coronavirus or rotavirus? why?
coronavirus because it infects the crypt and villous enterocytes. rotavirus just infects the villous cells
which bacteria causing diarrhea in calves is provincially reportable?
salmonella enterica subsp enterica
which salmonella serovar causes systemic disease in young and adult cows, and which serovar causes acute diarrhea and outbreaks in calves less than 2 months old?
S. dublin: systemic disease, young and adults
S. typhimurium: acute diarrhea, outbreaks less than 2 months of age
which diarrhea pathogen infects calves usually before 28 days of age, and can cause a chronic carrier state?
salmonella enterica
You go see a set of calves that are 20 days old, all with a transient fever, dullness, anorexia, malodourous diarrhea with some mucus and blood, and are a little cold. When talking with the farmer, you also found one calf dead on the ground. What pathogen are you worried about
salmonella