Avian digestion

CAP6

What is the rhamphotheca?

The outermost layer of the beak.

What is the function of the choana in birds?

Connects the nasal cavity to the oropharynx.

What is the role of the tongue in birds during inspiration?

Closes the choana.

What is the main difference in salivary glands between birds and mammals?

Birds have variable salivary glands.

What is the crop in birds?

A dilatation of the oesophagus used for food storage.

Where is the crop located?

Proximal to the pectoral cavity/thoracic inlet.

What is the proventriculus?

The glandular stomach of birds.

What is the ventriculus?

The muscular stomach (gizzard) of birds.

What is the function of the ventriculus?

Grinds food with grit.

What is the small intestine in birds?

Relatively short with villi.

What is the function of Meckel's diverticulum?

Contains lymphoid tissue.

What are caeca in birds?

Paired pouches involved in digestion and absorption.

What is the cloaca?

A common excretory passage for digestive, urinary, and reproductive systems.

What are the three sections of the cloaca?

Coprodeum, urodeum, and proctodeum.

What is avian ganglioneuritis?

A condition affecting the nerves of the gastrointestinal tract.

What is proventricular dilatation disease?

A form of avian ganglioneuritis affecting the stomach.

What are common clinical signs of gastrointestinal diseases in birds?

Anorexia, dysphagia, regurgitation, vomiting, constipation, diarrhea.

What is the role of the pancreas in birds?

Produces digestive enzymes and hormones.

How do dietary strategies influence avian digestive anatomy?

Different diets lead to variations in beak shape, crop size, and intestinal length.

What is the difference between granivorous and carnivorous bird digestive systems?

Granivorous birds have a well-developed ventriculus and longer intestines; carnivorous birds have a well-developed proventriculus and shorter intestines.

What is the avian coelom?

The body cavity containing organs.

What is unique about the avian respiratory system in relation to digestion?

No diaphragm, with air sacs that can affect digestive organ positioning.

How does the liver function in birds?

Produces bile and filters blood.

What is the role of the gallbladder in birds?

Stores bile; its presence is variable among species.

What is the significance of gut-associated lymphoid tissue (GALT) in birds?

Provides immune defense in the digestive tract.