GI Part 1

Question 1

What kind of GIT to carnivores have?

Answer 1

Big stomach, short intestinal tract

Question 2

What kind of GIT do birds have?

Answer 2

Food stored in crop, glandular stomach + muscular stomach (gizzard)

Question 3

Major functions of GIT:

Answer 3

Transport food
Digest absorbable particles 
Absorption of food components --> blood
Regulate water + electrolyte balance 
Immunologic barrier (GALT)
Thermoregulation

Question 4

Species difference in how cattle eat?

Answer 4

Wrap tongue around forage and incisors

Question 5

Species difference in how pigs eat?

Answer 5

Snout and mandible

Question 6

Mastication in carnivores:

Answer 6

Movement of mandible vertical. Molars + premolars in upper and lower jaws move against each other like scissors

Question 7

Mastication in herbivores

Answer 7

Spend long time masticating, upper and lower jaws are large, providing room for teeth with large chewing surfaces. Mastication movement = horizontal

Question 8

What step is after mastication?

Answer 8

Motility of GI tract segments

Question 9

4 functions of GI tract movements?

Answer 9

To propel ingesta
To retain ingesta at a given site for digestion, absorption, storage
To break up food material physically and mix with digestive secretions
To circulate ingesta so all portions come into contact with absorptive surfaces

Question 10

What is the first motility pattern in the GIT?

Answer 10

Deglutition

Question 11

What are the 2 phases of deglutition?

Answer 11

Voluntary and involuntary

Question 12

What is the voluntary phase of deglutition?

Answer 12

Aka oral phase
Food molded into bolus and pushed into pharynx using tongue –> activation of sensory nerves –> initiation of involuntary part of deglutition

Question 13

What is the involuntary phase of deglutition?

Answer 13

Aka swallow reflex

Occurs in pharynx + esophagus –> directs food into digestive system away from upper airways

Question 14

What is the deglutition transit time in dogs (oral cavity to stomach)?

Answer 14

4-5 seconds

Question 15

4 steps in deglutition

Answer 15

1. (Respiration stops momentarily) Soft palate elevated and closes nasopharynx to prevent food from entering nostrils
2. Tongue pressed against hard palate to close oropharynx
3. Epiglottis moved backwards to cover trachea
4. Upper esophageal sphincter opens –> peristaltic contractions. Now trachea can be reopened and respiration continues

Question 16

What do disorders of deglutition have in common?

Answer 16

Difficulty in swallowing which may result from NM disorder or mechanical obstruction

Question 17

What are the 2 types of dysphagia?

Answer 17

Oropharyngeal + esophageal

Question 18

What is oropharyngeal dysphagia?

Answer 18

Malfunction of pharynx + upper esophageal sphincter

Question 19

What is esophageal dysphagia?

Answer 19

Malfunction of esophagus

Question 20

What is aspiration?

Answer 20

A dysphagia in which food particles / fluids, or stomach contents (acid reflux) reach upper airways

Question 21

Major salivary glands?

Answer 21

Parotid, mandibular, sublingual

Question 22

Small salivary glands?

Answer 22

Ventral jaw glands, palate + pharyngeal glands, lip glands, zygomatic glands

Question 23

Serous type of secretion?

Answer 23

Parotid, lingulaes, bucales

Question 24

Mucous type of secretion?

Answer 24

Paracarunculares, bucales

Question 25

Seromucous secretion?

Answer 25

Mandibular, sublingual, labials

Question 26

What are the primary functions of saliva?

Answer 26

Protect buccal mucosa/teeth
Facilitate deglutition
Initiate enzymatic carb digestion
PH regulation (HCO3-)

Question 27

Secondary functions:

Answer 27

Immunological (lysozymes, IgGs), thermoregulation (panting), defense (llamas, alpacas)