Ruminants - Goats



Pre-Small Intestine (Group 4 - Rose S)






Small Intestine (Group 4 - Emily N)


The capacity of the goat’s small intestine is roughly two and a half gallons and is about 100 feet long.

The layers of the small intestine are (from outer to inner): the external layer, which has connective tissues for support and protection; a smooth muscle layer, for movement of the feed (peristalsis); any connective tissues that contain nerves, blood, and lymphatic vessels; and the epithelium that contains enterocytes (intestinal cells) that are located on the villi.

Partially digested feed enters the first part of the small intestine, the duodenum, where pancreatic enzymes (zymogens these are inactive enzymes, lipase, and amylase) break down the nutrients into simple compounds. To digest anything, zymogens, particularly trypsinogen, need to be activated. Enterokinase is used to activate the trypsinogen to become trypsin, so it can digest protein. Trypsin is used to activate the other protein zymogens, such as chymotrypsinogen, proelastase, procarboxypeptidase A, and procarboxypeptidase B. These enzymes reduce any remaining proteins to amino acids, these enzymes only do protein--the rest of these are digested by amylase, maltase, sucrase, lactase and lipase for the fats. starch to glucose, and complex fats into fatty acids.

The compounds are then absorbed in the jejunum through villi into the bloodstream or lymphatic vessels. The nutrients are absorbed three different ways: simple diffusion, which requires no energy; facilitated diffusion, which needs the help of a carrier; and active transport, which requires energy. The jejunum is where the most nutrient absorption takes place and has the most surface area.

The ileum takes up the task of any residual absorption of nutrients from the rest of the small intestine.

Large Intestine and Post Large Intestine (Group 4 - Kayla R)


Large Intestine: This portion of the Gastro-Intestinal Tract is made up of 3 portions: the cecum, the colon, and the rectum.

Cecum: This is the active site for the digestion of fibrous materials. It is also where Volatile Fatty Acids are produced by microbes. VMFA’s are then used for energy and are absorbed through the cecal wall. Synthesis of B-vitamins by microbes also happens here.

Colon: The colon serves the same function as the cecum with a slower rate of passage. It aids in microbial digestion, VMF for fatty A synthesis, and the synthesis of B-vitamins. Water reabsorption and the concentration of feces also happens here.

Rectum: This is where any and all of the undigested material is formed into feces.


Anus: This is the “Post Large Intestine” section. It controls the exit of feces and is also the alimentary tract.