Lecture 21 - Alimentary Two

Question 1

Describe the distribution of visceral afferent innervation:

Answer 1

Visceral afferent fibres travel with sympathetic and paasympathetic nerves

Question 2

What afferent receptors pick up extreme stretch and chemo nociception and what is the pathway to the brain?

Answer 2

Primary afferent C fibres and travel via the spinothalamic pathway to the brain

Question 3

Where are the stretch receptors located?

Answer 3

1. In muscular layers of hollow viscera between muscularis and mucosa/submucosa 2. Serosa of solid organs 3. In mesentery especially associated with large vessels

Question 4

Where are the chemoreceptors located?

Answer 4

Respond to variety of chemical stimuli. Located in the mucosa and submucosa of hollow viscera

Question 5

State the four ways stretch receptors are activated and provide an example of each:

Answer 5

1. Distention of hollow viscous - GIT obstruction 2. Forceful muscular contractions - parturition 3. Stretching of solid organ serosa or capsule - hepatic congestion or pancreatitis 4. Stretching of mesentry or mesenteric vessels - e.g. neoplasia

Question 6

What are the two cases in which chemical receptors are activated? Provide an example of each:

Answer 6

1. Inflammation - GIT obstruction of ulceration 2. Tissue ischemia or necrosis - GDV

Question 7

What are the three different types of obstruction?

Answer 7

1. Simple obstruction 2. Closed loop obstruction 3. Strangulation obstruction

Question 8

Name the intestinal obstruction that is shown below and then state:

1. Type of nociceptor that is activated
2. Possible sequalae

Answer 8

Phytobezoar

1. Stretch nociceptor
2. Build up to intestinal fluid proximal to the lesion and pressure necrosis of the mucosa in contact with the bezoar

Question 9

Provide an examples of two types of closed loop obstruction and state the type of nociceptor that is activated in each case:

Answer 9

1. External - ulcerated umbilical hernia and internal - incarceration of small intestine through the epiploic foramen
2. In both of these cases the nociceptors are activated by stretch and chemicals

Question 10

What are the two different types of strangulation obstructions shown below?

Answer 10

Top - volvulus

Bottom - torsion around a pedunculated lipoma

Question 11

What is the name of the condition that is shown below?

Answer 11

540 degree gastric torsion

Question 12

What is the name of the condition that is shown below?

Answer 12

Caecal torsion

Question 13

What is the name of the condition that is shown below?

Answer 13

Left Displaced abomasum (cows )

Question 14

What is the name of the condition that is shown below?

Answer 14

Gastric dilation volvulus - GDV (dogs)

Question 15

Name the condition that is shown in the cow below:

Answer 15

Right-sided abomasal torsion (cows)m

Question 16

What is a paralytic ileus?

What could be a cause?

What type of nociceptor is activated?

Answer 16

1. Failure of intestinal contents to be propelled aborally
2. Gastrointestinal surgery - inadequate decompression of the gut
3. Can be associated with electrolyte imbalanced (e.g. endurance horses), peritonitis and toxaemia

Question 17

What is the name of the condition shown below in the colon of the horse? What is the cause of it? What are some potential sequaelae?

Answer 17

1. Vascular bowel disease
2. Associated due to migrating stages of S.vulgaris
3. In severe cases, this causes segmental infarcts of colonic wall

Question 18

Fill in the blanks in the diagram below:

Answer 18

Question 19

How do clinical signs that are associated with abdominal pain vary between species?

Answer 19

Marked species differences in manifestation of abdominal pain - signs are more severe when both stretch and chemicals activate nociceptors. Signs are more obvious in horses and less obvious in ruminants

Question 20

What are the signs seen in abdominal pain in dogs?

Answer 20

Depression, licking abdomen, whining, growling, snapping to less conspicous (tense abdomen, grunting, trying to walk away when palpated)

Question 21

What are the clinical signs seen in abdominal pain in catttle?

Answer 21

Kicking the abdomen, positive grunt test

Question 22

What are the clinical signs seen in acute abdominal pain in horses (colic)?

Answer 22

1. Agitated appearance
2. Grinding teeth
3. Constantely looking at flank
4. Sweating
5. Not eating
6. Lying in lateral recumbency

Question 23

Why is there failure to pass gas and faeces in GI obstruction?

Answer 23

Associated with:

1. Emptying of intestine distal to obstruction
2. Reflex reduction in intestinal motility

Question 24

What is reduced/absent intestinal borborygmi typically associated with?

Answer 24

• Distention of intestine with fluid and gas
• Reflex neural inhibition
• Reduced blood supply
• Hypovolaemia, acid-base and electrolyte disturbances
• Endotoxaemia

Question 25

What is abdominal distention typically associated with?

Answer 25

Associated with accumulation of fluid and gas proximal to site of obstruction. Continued fermentation in large intestine, with production of gas that cannot be eliminated due to reduced intestinal motility.

Question 26

What are some of the side effects from prolonged vomiting?

Answer 26

Tachycardia, hypovolaemic and endotoxic shock

Question 27

Name the condition that has occured in the horse below:

Answer 27

Small intestinal entrapement through the epiploic foramen

Question 28

What is the name of the condition that is shown below?

Answer 28

Caecal rupture with peritonitis 3