Avian - Robins




Pre-Small Intestine (Group 1 - Reid C)





Small Intestine (Group 1 - Kim C)

Small Intestine- There is no distinction no between jejunum and ileum. The small intestine receives bile from the liver, digestion of enzymes from the pancreas, and absorbs epithelial cells.--the SI makes epithelial cells and then when they slough off the villi, it can break them down and use them for nutrients.

Duodenum- active site of digestion and pancreatic secretion from pancreatic duct. Pancreatic juice contains zymogens inactive enzymes. There are five zymogen that can be activated. The first is trypsinogen which is activated by enterokinase and the enzyme is trypsin. The second chymotrypsinogen which is activated by trypsin and the enzyme is chymotrypsin. The third is proelastase which is activated by trypsin and the enzyme is elastase. The forth is procaroxypeptidase A which is activated by trypsin and the enzyme is caroxypeptidase. The last is procaroxypeptidase B which is activated by trypsin and the enzyme is caroxypeptidase.
Jejunum- most nutrient absorption, longest and most surface area, and there is three mechanisms of absorption which are simple/passive diffusion which has no energy, facilitated diffusion which helps carrier, and active transport which requires energy.
Ileum- is residual nutrient absorption.




Large Intestine (Group 1 - Courtney A)

The large intestine consists of a short colon and a pair of ceca.--the ceca come first, then colon. Short villi are present in the lumen of the colon. The large intestine's primary function is to absorb water and electrolytes. The large intestine is fairly short in comparison to that of a mammal in order for the bird to eliminate quickly in order to fly.--never thought about that, haha.




Post Large Intestine (Group 1 - Whitney B)

The two parts post large intestine are the cloaca and the vent. The Cloaca (similar to a rectum) is the opening for digestive urinary and reproductive tract. Mixing of feces and urine occurs and often has a white powder look once released. The white powder is known as uric acid (The avian form of urine). The cloaca also serves as the reporoductive tract. This is also the opening for the delivery of eggs.When laying an egg, the vagina folds over to allow the egg to leave without touching feces or urine.--isn't that so cool?