CA09/10 - Diarrhoea

Why might you see tachycardia in cases of enteric disease?

Dehydration/stress

What are signs of dehydration?

Skin tent ± sunken eyeball (remember also caused by emaciation)

What are some diagnostics you can run on a fecal sample?

• Culture and sensitivity, e.g. E. coli, Salmonella

• McMasters, e.g. Coccidia spp. , strongyles

• Sporulation , e.g. Eimeria species

• SNAP test, e.g. E.coli, crypto, rota and coronavirus

What does a serology (ELISA) for BVD look for?

Antibody

What AGE OF CALF is Enterotoxigenic E.coli (ETEC) suspected?

less than 1 week old (usually 1-3 days old)

Enterotoxigenic E.coli (ETEC) causes a ____ decline to recumbency in calves 

usually very rapid decline to recumbency (dehydration)

Enterotoxigenic E.coli (ETEC) causes a ____ HR and _____ resp rate in calves 

rapid HR (dehydration), normal to increased resp rate 

What findings does Enterotoxigenic E.coli (ETEC) produce on abdominal palpation and auscultation?

bloated looking and sloshing on ballotment (due to gut stasis and sequestration of fluid in abomasum and jejunum

What type of diarrhea does Enterotoxigenic E.coli (ETEC) produce?

Profuse yellow to white diarrhea without mucous or blood 

Does Enterotoxigenic E.coli (ETEC) cause pyrexia?

Yes, rapidly progressing to hypothermia (dehydration & circulatory collapse)

Enterotoxigenic E.coli (ETEC) causes a _____ diarrhea. What does that mean?

secretory diarrhea

• Bacteria adheres to gut mucosal cells & releases a toxin that causes hypersecretion of water, sodium, chloride into the gut lumen

• This fluid is lost as the villi cannot reabsorb the fluid due to osmotic pressure in the lumen

• This leads to rapid dehydration

• The villi largely remain intact and calves are not usually acidotic

What is the tx of Enterotoxigenic E.coli (ETEC) in calves?

Correct dehydration, replenish on-going losses (IV or oral fluids), cover with antibiotics if suspect septicemia or navel ill 

How to prevent Enterotoxigenic E.coli (ETEC)?

• Maintain CLEANLINESS

• COLOSTRUM - quantity, quality, quickly

• Consider vaccination in late gestation —> antibody to calf as long as enough colostrum is consumed

What AGE OF CALF is colisepticaemia and meningitis suspected in calves?

Less than 2 weeks old

What DEMEANOR do calves with colisepticaemia and meningitis have?

Lethargic, obtunded, recumbent, seizures (grave prognosis), neuro abnormalities 

Calves with colisepticaemia and meningitis have a(n) _____ HR and _____ resp rate

increased HR (tachycardic), normal to increased resp rate

What are some ocular signs of colisepticaemia and meningitis in calves?

Nystagmus, episcleral congestion

What kind of diarrhea do calves with colisepticaemia and meningitis have?

Agonal stage diarrhea, mucoid

What is the tx for calves with colisepticaemia and meningitis?

IV antibiotic (trimethoprim sulphadiazine, suitable prep of oxytetracycline, marbofloxacin/enrofloxacin after C&S), pain relief, NSAIDs or steroids, IV fluids, supportive care

PROGNOSIS POOR

How would you prevent colisepticaemia and meningitis in calves?

• the 3Qs of colostrum

• clean environment

• maternal vax

What AGE do calves get rotavirus?

Generally 1-2 weeks old (can be older)

What DEMEANOR would a calf with rotavirus have?

Weakness, sternal/lateral recumbency, obtunded, unresponsive

Rotavirus in calves causes _____ (HR) and ______ (resp rate)

tachycardia, tachypnoea (acidotic)

What would you find on ABDOMINAL PALPATION and AUSCULTATION of a calf with rotavirus?

Bloated belly and sloshing on ballotment

What kind of DIARRHEA (color, consistency) does rotavirus cause?

Watery yellow green diarrhea 

How can you DIAGNOSE rotavirus in calves?

SNAP test, blood gas machines to confirm acidosis

As a rule of thumb, calves ___ - ____ days old with diarrhea will have metabolic acidosis.

6-30 days old

What is the PATHOPHYSIOLOGY of rotavirus?

• Virus replicates in epithelial cells of S.I 

• Desquamation of absorptive mature cells at the tips of the villi 

• Damage —> decr absorption of water and electrolytes —> loss of K+, Na+, bicarb

• Fluids, electrolytes, & undigested feed passed into the colon —> colonic fermentation —> osmotic diarrhea as water is drawn into the colon 

• Metabolic acidosis is caused by loss of bicarb and incr absorption of H+ ions 

What is the TREATMENT for calves with rotavirus?

IV fluids to correct base deficit, NSAIDS (meloxicam) to reduce inflammation of gut if >1 week old

How would you PREVENT rotavirus in calves?

• 3 Qs of colostrum

• Maternal vax

• Shorten calving period

• Remove freshly calved cows and calves promptly

  • Concurrent crypto infection can exacerbate infection and lead to clinical disease

How does coronavirus compare to rotavirus in calves?

Coronavirus is RARER, but more SEVERE, most likely to cause disease in 2-3 week old calf

What AGE do calves usually get Cryptosporidium?

7 days to 3 weeks old

What is the TREATMENT for calves with Cryptosporidium?

Can be self-limiting, supportive care to correct dehydration (IV or oral fluids)

What is the role of Halofuginone in Cryptosporidium in calves?

Available for very bad outbreaks as treatment and prevention, has to be given 7 days either from start of signs or day 1-2 of life 

• Low toxicity index so dose appropriately 

How can farmers prevent Cryptosporidium?

HYGIENE

• Do not graze lambs and calves on the same pasture, even in alternating years (calves can act as a source for lambs)

• Thoroughly clean and disinfect pens / sheds following the calving / lambing season. The protozoa are very difficult to destroy. Special disinfectants are required. Heat washing and complete drying can reduce oocyst load

What are some DEMEANOR signs of coccidiosis?

Chronic wasting, poor appetite, tucked up and dull with a rough fleece / coat, cocked tails, straining with groaning

What can you do to test for Coccidiosis?

McMasters - for oocyst count

Sporulation - to ID species

Name 2 of the most common Salmonella enterica serotypes in UK cattle

• S. Dublin

• S. Typhimurium

What is the difference between the two Salmonella enterica serotypes, S. Dublin and S. Typhimurium?

S. Dublin

• Host adapted to cattle, not zoonotic

• MEMORY: Think Dublin is a small city that doesn’t have a zoo

S. Typhimurium

• In outbreaks caused by S. Typhimurium, DT104 is the most prevalent phage type causing disease in UK cattle

• very ZOONOTIC

Salmonella is often, but not always, a disease of (adult/young) cattle

ADULT

What AGE are calves affected by Salmonella?

2-6 weeks old

What is the cause of Winter Dystentry?

Unknown, but coronavirus has been found in feces