Lecture 9: Avian Digestive Physiology Flashcards
Combined cavity of mouth and pharynx extending from beak to esophagus
Oropharynx
Reduces feed to smaller size
Beak
Caudal to base of tongue w/ median slit
Laryngeal mound
T/F: Avians have no epiglottis
True
T/F: Avians do not have taste buds
False
Avian saliva composition
Mostly mucus, some amylase
Crop is located near
Thoracic inlet
Can store food when rapidly eating, small amount of fermentation, moistens/releases food slowly to rest of GIT
Crop
Post-crop esophagus is located
Thoracic region
Avian stomach components
Proventriculus and gizzard
Gastric chamber that secretes HCl, pepsinogen, gastric lipase, mucus
Proventriculus
Mechanical grinding occurs here
Gizzard (Ventriculus)
Accumulation of grit and stone to help grind
Gizzard
What is gizzard lined with?
Koilin
What is the purpose of koilin in the gizzard?
Solid secretions to protect gizzard from acid + pepsin
Intestines in birds are long or short compared to mammals?
Short
Pancreas is located in the center of the
Duodenal loop
How many pancreatic ducts does avian have?
3
Meckel’s diverticulum
Yolk sac vestige, distinction between jejunum and ileum
How many rhythmic gastroduodenal contractions do avians have?
~3/min
In gastroduodenal contractions, which muscles contract first?
Thin ventricular muscles
What does the peristaltic wave through ventriculus follow?
Contraction of thick ventricular muscles
What happens to digesta from the duodenum and upper jejunum about 4x an hour?
Refluxes into ventriculus
What is only allowed in ceca?
Liquids
Ceca in avians are
Paired
Water reabsorbed from refluxed urine provides
N for bacteria
Where feces and urine are excreted together, where excrete N as uric acid
Cloaca
Opening to exterior for feces
Vent
Bursa of Fabricius
Immune function
Antiperistalsis in the colon is
When urine moved from cloaca to ceca and colon
How many antiperistaltic contractions/minute?
10-14
The major cecal contractions are for
Cecal evaluation
One major cecal contraction for
Defecation
Minor cecal contractions are for
Mixing
How many lobes in liver of avians
Bi-lobed
How many cecal droppings per day?
1-2
How many intestinal droppings per day?
25-50
Best diet for poultry
Highly digestible start and protein diets
Impacted crop occurs from
Consuming too much grass and fibrous materials
Can happen if fasting then binge
If food fails to move out of crop, could be obstruction
Sour crop occurs from
Overgrowth of yeast in crop, which disrupts normal bacteria