Equine Digestion and Rotavirus Flashcards
functions of the digestive system
digestion and absorption
digestion
process of breaking down complex molecules into simple molecules
absorption
process of transporting simple molecules across intestinal epithelium into the bloodstream
mouth
digestion begins here, the teeth grind food and cover it in saliva, has neutral pH to help buffer the stomach
esophagus
tube connecting the mouth to the stomach
stomach
gastric juices, digestion of protein, pH is about 2
small intestine
emzymatic digestion. bile from liver digests fat, pancreas helps in the digestion of protein, fat and starch. majority of sugars are absorbed in the small intestine, leading to increased blood glucose 30 mins after a meal. vitamins and minerals are also absorbed here. large volumes of water are secreted into the small intestine during digestion
large intestine
cecum, large and small colon, microbial fermentation of material that was not digested in the small intestine (fiber) and water reabsorption
types of plant carbohydrates
fiber, sugar and starch
fiber
structural part of plants, important energy source for herbivores. fiber cannot be digested by mammalian enzymes and needs to be broken down by microbes through fermentation
water
water movement in intestine is always through osmosis, moves in whatever direction necessary to keep ingest iso-osmotic, entering gut when it is hyper osmotic and leaving gut when ingesta is hypo-osmotic, water absorption is dependent on nutrient absorption
diarrhea
increase in frequency of dedication or fecal volume due to increased water content, water in the GI tract is the sum of ingested water and water secreted by the intestines, when water absorbed is less than the sum of the water secreted and ingested, there is water in the passage of feces
when does diarrhea occur
mismatch between secretion and absorption, occurs when the absorption is inadequate to recover secreted water generally because of loss of GI epithelium, bacterial, viral or protozoal infection
equine rotavirus definition
most common cause of foal enteritis, the virus only affects foals
how is rotavirus transmitted?
fecal-oral route through contaminated feces or fomites, no natural reservoir has been identified, mares do not shed the virus, large concentrations of the virus are shed into the envt by a diarrheic animal
how long can the virus remain in the environment?
may remain in the environment for up to 9 months, incubation period is 12-24 hours, close to 100% of broodmares are seropositive for the virus, duration of diarrhea is 1-9 days and foals continue to shed the virus up to 3 days after the virus recedes
effects of rotavirus
with supportive care, it has a high morbidity and low mortality, after recovering foals generally don’t get the virus again
pathogenesis
destroys the villous tips in duodenum and jejunum, blunting the villi. this results in hyper osmotic solution in the intestine, malabsorption and maldigestion of nutrients causes influx of water into the intestinal lumen
rotavirus clinical signs
lethargy, decreased suckling, diarrhea, may be projectile diarrhea, fever may or may not be present, dehydration
diagnosis
fecal samples, need 3 negative tests to rule out rotavirus, differential diagnosis may be salmonella, clostridium and parasites
treatment
IV fluids with electrolytes, peptobysmol, mineral oil, activated charcoal, may need antibiotics, NSAIDs for pain, omprazole to prevent ulcers, clean and dry stalls, diaper rash cream
disinfection
stable in pH of 3-7, resistant to iodophor, quaternary ammonium, chlorine and bleach, ethanol and formalin can inactivate the virus
prevention
vaccinate mares at 8,9 and 10 months, do not spread manure or muck of affected animals to pasture as virus can remain viable for months, compost manure
