Stomach, Abomasum, Rumen

Question 1

Ruminal Tympany

Answer 1

Over-distention of the rumen and reticulum with gases of fermentation

Question 2

Primary Tympany

Answer 2

Dietary in origin (legumes - alfalfa, ladino clover)

Soluble Leaf Cytoplasmic Proteins = FOAM

1 hour to 2-3 days

Question 3

Pathogenesis of frothy bloat / primary ruminal tympany

Answer 3

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

Question 4

Make up of foam from primary tympany

Answer 4

Gas

Soluble leaf proteins

Bacterial slime

Question 5

Secondary Tympany

Answer 5

Due to physical or functional obstruction

(tumor, papilloma, stenosis, etc, organophosphates, vagal nerve damage)

(foreign body - trichobezoars, phytobezoars)

Gas packets - NO FOAM / FROTH

Question 6

Pathogenesis of ruminal lactic acidosis

Answer 6

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

Question 7

Sequelae to ruminal lactic acidosis

Answer 7

Necrotizing bacterial rumenitis

Secondary mycotic rumenititis

Secondary hepatitis due to septicemia

All can lead to death

Question 8

How can cutaneous mast cell tumor cause gastric ulcers in dogs?

Answer 8

Mast cell tumor >

Elevated histamine in bloodstream >

Bind to H-2 receptors on parietal cells >

Increased HCl secretion >

Mucosal ulcer

Question 9

Predisposing conditions for GDV

What other organ is often affected?

Answer 9

Large breed

Deep chested

Large meal (dry, high fat or oil)

Exercise after meal

Splenomegaly

Question 10

Causes of ulcers in:

Cattle

vs.

Pigs

Answer 10

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

Question 11

Location of ulcers in:

Cattle

vs.

Pig

Answer 11

Cattle

Greater curvature of fundic and pyloric regions

Pig

Pars esophagea (where lined by stratified squamous epithelium)

Question 12

Pathologic sequelae of gastric ulcers in pigs and abomasal ulcers in cattle

Answer 12

Don’t know?????

Question 13

What is reticuloperitonitis?

Answer 13

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

Question 14

Most common cause of reticuloperitonitis

Answer 14

Wire

Question 15

Pathogenesis of bovine mucosal disease

Answer 15

Contact exposure >
Replication in upper GI >
Viremia >
Extensive lymphocyte infection and necrosis >
Viremia with localization in the GIT, skin, other lymphoid tissues

Question 16

Causative agent of bovine mucosal disease

Answer 16

Family - Flaviviridae

Genus - Pestivirus

(Bovine virus diarrhea)

Question 17

Significance of bovine Persitently Infected (PI) with bovine mucosal disease

Answer 17

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

Question 18

How are PI cattle identified?

Answer 18

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)

Question 19

What is the usual site of origin of gastric adenocarcinoma in the canine?

Answer 19

Pyloric antrum

(with extension into the body - usually along the lesser curvature)

Question 20

Standard methods to collect pathology tissue from the alimentary tract of live dogs and cats

Answer 20

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)

Question 21

Clinical signs of parvo in

Feline

Canine

Answer 21

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

Question 22

Gross lesions of parvo in

Feline

Canine

Answer 22

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

Question 23

Diagnostic tests for parvo

Answer 23

ELISA (antigen test), EM

(from class google doc)

Question 24

Are fecal antigen tests or fecal electron microscopic findings always positive in cases of parvoviral enteritis?

Answer 24

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)