GI

Question 1

Cholangioliths found in horses are usually composed of:

a. Calcium carbonate
b. Struvite
c. Calcium bilirubinate
d. Magnesium carbonate

Answer 1

c. Calcium bilirubinate

Biliary stone formation begins with precipitation or aggregation of normally soluble components of bile. Other mechanisms involved in the pathogenesis include ascariasis, ascending biliary infection or inflammation, biliary stasis, changes in bile composition, and presence of a foreign body.

Smith, Bradford P.. Large Animal Internal Medicine, Elsevier, 2014.

Question 2

The prevalence of gastric ulcers in horses is influenced by a range of factors. Which one of the following below does not influence the prevalence of gastric ulcers?

Answer 2

a. Type and intensity of training
b. Gender and age
c. Type of housing
d. Feeding practices

Question 3

A 21-day-old Morgan filly presents for evaluation of loss of suckle, weakness, lethargy and icterus. Evaluation of a serum biochemical profile reveals evidence of hepatic compromise.
Of the following options, what is the MOST likely cause?

A. Clostridum novyi type B
B. Clostridium piliforme
C. Equine Herpesvirus
D. Hyperammonemia of Morgans

Answer 3

B. Clostridium piliforme

Ref: Reed, Bayly & Sellon 3rd ed. p. 959.

Question 4

Which of the following serum biochemical parameters can be markedly above adult reference interval when measured in healthy neonatal foals?

A. Albumin
B. Bile acids
C. Creatine kinase
D. Troponin I

Answer 4

B. Bile acids

Ref: Barton JVIM Volume 21 Issue 3, Pages 508 – 513.

Question 5

Which of the following stimulates secretion of aqueous components of pancreatic juice?

a. Cholecystokinin
b. Secretin
c. Serotonin
d. Motilin

Answer 5

b. Secretin

Question 6

Where and in response to what is secretin secreted?

Answer 6

Secreted from the S cells in the duodenal mucosa in response to the prescence of acidic gastric juice

Question 7

What is the effect of secretin?

Answer 7

mild inhibition of most GI motility

Question 8

Where and in response to what is cholecystokinin secreted?

Answer 8

secreted from the I cells in the SI mucosa in response to the presence of fat, fatty acids and monoglycerides.

Question 9

What is the effect of cholecystokinin?

Answer 9

increase gallbladder contraction and inhibit stomach motility

Question 10

Which of the following statements regarding gastrin is false?

a. Stimulates increased lower esophageal pressure to prevent gastric emptying.
b. Stimulates proliferation of the gastric mucosa.
c. Is produced by Type G cells.
d. Inhibits pancreatic bicrbonate production and pancreatic flow

Answer 10

d. Inhibits pancreatic bicrbonate production and pancreatic flow

Gastrin weakly promotes pancreatic HCO3 production and flow.

Question 11

Mention the effect and the production site of somatostatin.

Answer 11

inhibits gastric activity and is released from duodenal mucosa and pancreatic cells

Question 12

What are the factors that depolarize the GI smooth muscle cell membrane?

Answer 12

Stretching, stimulation of the parasympathetic nervous system (ACH) and stimulation by particular GI hormones.

Question 13

What are the factors that hyperpolarize the GI smooth muscle cell membrane?

Answer 13

Norepinephrine or epinephrine from the adrenals and stimulation of the sympathetic nervous system (NE)

Question 14

Which of the following substances secreted primarily by the pancreas is requiered for intestinal absorption of Vit B12?

a. Intrinsic factor
b. Gastrin
c. Cholecystokinin
d. Pepsin

Answer 14

a. Intrinsic factor

Question 15

Gastrin is secreted by which cell type?

a. Enterochromaffin-like cells in the pyloric glands
b. G-cells in the pyloric glands
c. Parietal cells in the gastric glands of the body of the stomach
d. Delta cells in the pancreatic islets of Langerhans

Answer 15

b. G-cells in the pyloric glands

Question 16

Which of the following is a correct statement regarding GI hormone secretion, stimulation and function?

a. Cholecystokinin (CCK) is secreted from I cells of the antral mucosa in response to fatty substances and functions in gallbladder contraction.
b. GI peptide is secreted from the upper SI in response to mainly fatty substances in chyme and functions in secretion of glucagon by pancreas.
c. Motilin is secreted by the upper duodenum during fasting and functions to increase GI motility.
d. Gastrin is secreted from G cells located in the pyloric glands of the distal end of the stomach in response to fatty substances in chyme and functions in the stimulation of gastric acid secretion.

Answer 16

c. Motilin is secreted by the upper duodenum during fasting and functions to increase GI motility.

Question 17

Which of the following is correct regarding acid secretion?

a. Parietal cells are located deep in pyloric glands and operate in close association with enterochromaffin-like cells.
b. The primary function of enterochromaffin-like cells is to secrete gastric acid.
c. The most potent mechanism for stimulating histamine secretion is by the hormonal substance secretin.
d. The parietal cells are the only cells that secrete gastric acid.

Answer 17

d. The parietal cells are the only cells that secrete gastric acid.

Question 18

Which of the following is primarily responsible for stimulating intestinal motility?

a) Enteric nervous system - myenteric plexus
b) Sympathetic nervous system
c) Enteric nervous system - submucosal plexus
d) The hormones gastrin and secretin

Answer 18

a) Enteric nervous system - myenteric plexus

Question 19

Which of the following stimulates secretion of the aqueous component of pancreatic juice?

a) Cholecystokinin
b) Secretin
c) Serotonin
d) Motilin

Answer 19

b) Secretin

Question 20

Hemorrhagic diathesis occurring secondary to hepatic failure is due to which of the following mechanisms?

a) Decreased production of Factor VIII
b) Decreased Vitamin K absorption
c) Hypoalbuminemia and decreased oncotic pressure
d) Immune-mediated extravascular hemolysis

Answer 20

b) Decreased Vitamin K absorption

Question 21

Which of the following probiotic bacteria has potential as a possible prevention and treatment of Johne’s disease

a) Bifidobacterium sp.
b) Dietza sp.
c) Lactobacillus sp.
d) Saccharomyces sp.

Answer 21

b) Dietza sp.

Question 22

Which of the following statement regarding the function of the liver in digestion and metabolism is CORRECT?

a) The liver produces bile, which helps to digest fats.
b) The liver converts urea to ammonia for excretion by the kidneys.
c) The liver is involved in the synthesis of some plasma proteins and amino acids.
d) When blood glucose is low, the liver converts glucose to glycogen.

Answer 22

c) The liver is involved in the synthesis of some plasma proteins and amino acids.

Question 23

What are common clinical signs of cholelithiasis?

Answer 23

Cholelithiasis should be suspected in horses when a triad of clinical signs exists: recurrent abdominal pain, intermittent pyrexia, and icterus.

Hyperammonemic hepatic encephalopathy, photosensitization, and weight loss are other, less common features of cholelithiasis.

Smith, Bradford P.. Large Animal Internal Medicine, Elsevier, 2014.

Question 24

The oxyntic glands of the stomach mucosa secrete all of the following except:

A. Hydrochloric acid
B. Pepsinogen
C. Gastrin
D. Mucus

Answer 24

C. Gastrin

Question 25

What are the three basic stimuli that are important in causing pancreatic secretion?

A. Acetylcholine, Cholecystokinin, Secretin
B. Bicarbonate, Cholecystokinin, Trypsin
C. Cholic acid, Cholecystokinin, Gastrin
D. Acetylcholine, Gastrin, Histamine

Answer 25

A. Acetylcholine, Cholecystokinin, Secretin

Question 26

Which of the following stimulates the secretion of water solution and sodium bicarbonates by the pancreatic ductal epithelium?

A. Acetylcholine
B. Cholecystokinin
C. Gastrin
D. Secretin

Answer 26

D. Secretin

Question 27

Which of these statements is false regarding the regulation of pancreatic secretions?

A. Somatostatin is released from the islets of Langerhans and inhibits acinar cell secretions
B. Cholecystokinin is released from the upper small intestines and causes release of pancreatic digestive enzymes
C. Acetylcholine is released from the parasympathetic nerve endings and stimulates the acinar cells to release pancreatic digestive enzymes
D. Secretin is released from the upper small intestines and causes release of a bicarbonate rich water solution from the acinar cells.

Answer 27

D. Secretin is released from the upper small intestines and causes release of a bicarbonate rich water solution from the acinar cells.

Question 28

Which of the following stimulates secretion of a sodium bicarbonate solution by pancreatic ductal epithelium?

A. Acetylcholine
B. Secretin
C. Cholecystokinin
D. Somatostatin

Answer 28

B. Secretin

Question 29

Which of the following stimulates secretion of exocrine pancreatic enzymes?

A. Secretin
B. Cholecystokinin
C. Acetylcholamine
D. Somatostatin

Answer 29

B. Cholecystokinin

Question 30

Which of the following statements is correct concerning somatostatin?

A. Stimulates enterochromaffin-like cells to secrete histamine
B. Is secreted into circulation by D cells in the pancreatic islets
C. It stimulates contraction of the gallbladder
D. Is produced by the S cells in the small intestine.

Answer 30

B. Is secreted into circulation by D cells in the pancreatic islets

Question 31

Which hormone is primarily responsible of relaxation of the sphincter of Oddi and gallbladder contractions?

a. Cholecystokinin
b. Gastrin
c. Secretin
d. Motilin

Answer 31

a. Cholecystokinin

Question 32

Which substance is secreted by the parietal cells of the stomach and can lead to pernicious anemia following severe gastritis?

a. Vitamin B12
b. Intrinsic factor
c. Acetycholine
d. Histamine

Answer 32

b. Intrinsic factor

Question 33

What are the causes of ruminal tympany?

Answer 33

• Obstruction of eructation (esophageal obstruction, cardia obstruction or failure to clear cardia of fluid or ingesta).
• Ruminal motor dysfunction (as trapped in stable foam, failure of smooth muscle contractions, weakened muscle contractions).
• Chemical inhibition (abomasal distention, vagus nerve damage, ruminal stasis).

Question 34

Mention some of the common ulcer invaders in ruminants.

Answer 34

Trueperella pyogenes, Fusobacterium necrophorum and several mycotic species.

Question 35

What are the 2 types of esophageal diverticula?

Answer 35

Traction (true) and pulsion diverticula (false)

Question 36

What is the difference between a traction and a pulsion esophageal diverticula?

Answer 36

A traction diverticula results from wounding and subsequent contraction of periesophageal tissues, appear as a dilation with broad neck and have little clinical significance.
A pulsion diverticula results from protrusion of esophageal mucosa mucosa through defects in the muscular wall of the esophagus and usually result from trauma or acute changes in intraluminal pressure, it typically has a flask shape with a small neck on an esophagram. Pulsion diverticula may fill with feed material, ultimately leading to esophageal obstruction.