Lecture 53- Avian Digestive Physiology Flashcards
Trace the avian GI tract
Beak and oropharynx
Pre-crop esophagus
Crop
Post-crop esophagus
Proventriculus (glandular stomach)
Gizzard (muscular stomach)
Duodenal loop
Small intestine (Jejunum and ileum)
Ceca
Large intestine (very short)
Cloaca
Vent
What is the oropharynx?
Combined cavity of mouth and pharynx extending from beak to esophagus
What is the laryngeal mound?
Caudal to base of the tongue with medial slit = glottis
No epiglottis guarding the glottis
Where is the pre-crop esophagus?
Cervical region
Where is the crop?
Near the thoracic inlet
What is throughout the esophagus?
Mucus glands
Ability to stretch and accommodate large food items
Where is the post-crop esophagus?
Thoracic region
What are the two aspects of the avian stomach?
Proventriculus—gastric chamber
Gizzard (ventricular)—mechanical grinding
Describe the gizzard
Very strong muscle
Small stones and grit accumulation
Lined with cuticle called koilin
*solid secretion to protect from acid and pepsin
*secretions solidly after exposure to acid
What is the distinction between Jejunum and ileum?
Meckel’s diverticulum
(TRUE/FALSE) intestines are much shorter in birds compared to mammals
TRUE
Important for birds that fly
Describe the gastroduodenal motility?
-contraction of thin ventricular muscles
-2 to 3 peristaltic waves through duodenum
-contraction of thick ventricular muscles
-peristaltic wave through ventricles
*about 4x/hr digesta from duodenum and upper Jejunum refluxes into ventriculus
What is the paired ceca separated from?
Ileum by ileocecal folds
Where is water reabsorbed from reflux urine?
Paired ceca
What is the cloaca?
Common opening for digestive, reproductive, urinary systems
Excrete feces and urine together
Urine is in form Urin acid
