Stomach, Abomasum, Rumen Flashcards
(24 cards)
Ruminal Tympany
Over-distention of the rumen and reticulum with gases of fermentation
Primary Tympany
Dietary in origin (legumes - alfalfa, ladino clover)
Soluble Leaf Cytoplasmic Proteins = FOAM
1 hour to 2-3 days
Pathogenesis of frothy bloat / primary ruminal tympany
Consume legumes (soluble cytoplasmic proteins)
Ruminal pH drops to 5-6
Ruminal bacteria produce slime, methane, CO2
Foam stablilizes
More gas & foam increase ruminal pressure to 45-70mmHG
Make up of foam from primary tympany
Gas
Soluble leaf proteins
Bacterial slime
Secondary Tympany
Due to physical or functional obstruction
(tumor, papilloma, stenosis, etc, organophosphates, vagal nerve damage)
(foreign body - trichobezoars, phytobezoars)
Gas packets - NO FOAM / FROTH
Pathogenesis of ruminal lactic acidosis
Feed cow high levels of grain
Fermentable carbohydrates > Strep. bovis and lactobacilli overgrowth > ferment carbohydrates to lactic acid > ruminal pH drops below 5
pH kills protozoa, normal flora, damages ruminal mucosa
Acidosis, dehydration, circulatory collapse > death
Sequelae to ruminal lactic acidosis
Necrotizing bacterial rumenitis
Secondary mycotic rumenititis
Secondary hepatitis due to septicemia
All can lead to death
How can cutaneous mast cell tumor cause gastric ulcers in dogs?
Mast cell tumor >
Elevated histamine in bloodstream >
Bind to H-2 receptors on parietal cells >
Increased HCl secretion >
Mucosal ulcer
Predisposing conditions for GDV
What other organ is often affected?
Large breed
Deep chested
Large meal (dry, high fat or oil)
Exercise after meal
Splenomegaly
Causes of ulcers in:
Cattle
vs.
Pigs
Cattle
Calves - dietary changes; milk to milk replacer/roughage
Feedlot - ulcers in pyloric antrum during first 1.5 months of winter fattening
Dairy - after parturition, hemorrhagic ulcers
pepsin, HCl leakage; increased epithelial permeability to gastric acid, blood flow disturbances (A-V shunt); steroids, NSAIDS depressing prostaglandin formation)
Pigs
High grain feeds (finely ground corn)
Stress
Location of ulcers in:
Cattle
vs.
Pig
Cattle
Greater curvature of fundic and pyloric regions
Pig
Pars esophagea (where lined by stratified squamous epithelium)
Pathologic sequelae of gastric ulcers in pigs and abomasal ulcers in cattle
Don’t know?????
What is reticuloperitonitis?
Perforation of the rumen by a foreign body
Usually a wire
Produces focal or locally extensive peritonitis or extends through the diaphragm to puncture pericardium and pleura
Most frequently puncture is in anteroventral direction
Hardware disease
Most common cause of reticuloperitonitis
Wire
Pathogenesis of bovine mucosal disease
Contact exposure >
Replication in upper GI >
Viremia >
Extensive lymphocyte infection and necrosis >
Viremia with localization in the GIT, skin, other lymphoid tissues
Causative agent of bovine mucosal disease
Family - Flaviviridae
Genus - Pestivirus
(Bovine virus diarrhea)
Significance of bovine Persitently Infected (PI) with bovine mucosal disease
They will always shed the virus
If infected with noncytopathic strain, cattle are susceptible to severe clinical disease when later exposed to cytopathic strain
PI females produce PI calves (can’t vaccinate)
PI cattle are the primary reservoir for BVDV
How are PI cattle identified?
1) Lesions and clinical signs
2) Virus isolation from buffy coat cells, spleen, lymph node or alimentary tract lesion
3) Immunofluorescence, PCR, ELISA on tissue (ear biopsy)
What is the usual site of origin of gastric adenocarcinoma in the canine?
Pyloric antrum
(with extension into the body - usually along the lesser curvature)
Standard methods to collect pathology tissue from the alimentary tract of live dogs and cats
Fine needle aspiration (guided by ultrasound or palpation of mass)
Core needle biopsy
Endoscope (2.8mm, distortion, prone to small sample size and inadequate thickness, easy to lose)
Full-thickness biopsy (requires abdominal surgery, fewer artifacts, grossly observe alimentary tract, larger tissue)
Clinical signs of parvo in
Feline
Canine
Feline
Sudden depression, anorexia, fever, vomiting
Diarrhea - dehydration & electrolyte abnormalities
Panleukopenia - depression of all leukocyte lines from bone marrow necrosis
Canine
Anorexia, depression, vomiting, diarrhea, dehydration
Gross lesions of parvo in
Feline
Canine
Feline
Carcass dehydration (dry subcutis, sunken eyes)
Flaccid small intestine can be segmentally reddened and contain scant, watery, yellow grey to clear contents
Bone marrow may be pale and gelatinous
Mesenteric lymph nodes are edematous or enlarged
Smaller than normal thymus in young cats
Canine
Segmental reddening of the small intestine
Small intestine may be covered with no or little yellow liquid and reddened
Thymic atrophy
Mesenteric lymph nodes either larger or smaller
Diagnostic tests for parvo
ELISA (antigen test), EM
(from class google doc)
Are fecal antigen tests or fecal electron microscopic findings always positive in cases of parvoviral enteritis?
No, findings will not always be positive. Shedding can occur before the onset of clinical signs. If ELISA is negative, shedding may have occurred earlier and the virus is no longer being produced by enterocytes.
(class google doc)
