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The large intestine consists of four areas; a large caecum or blind sac near the ileocolic valve; an ascending colon on the right side; a short transverse colon; and a descending colon heading posteriorly. The cecum is quite large in herbivores, like the rat, and may contain microorganisms, which further breakdown the plant material not already digested by the enzymes of the small intestine. The major function of the large intestine itself is the re-absorption of the large quantities of water secreted into the gut during digestion. Thus, as undigested material moves along the colon, water is removed from it, resulting in a mass of waste material, the feces. Feces are stored in the rectum (the terminal portion of the colon) until eliminated through the anus. (which is not part of the LI).
Post Large Intestine (Group 2 - Abigail F)
The feces of a rat are skinny pellets, about 3/8 inches long and 1/8 inch in diameter, rounded tips, slightly buldging in the center, fresh ones are dark and get lighter with age.

Hindgut Fermenters - Rabbits
Pre-Small Intestine (Group 2 - Abigail F)
A rabbits is a herbivore and have quite an amazing dental anatomy. They have about 8,000 taste buds and since their teeth are unrooted their incisors grow about 5 inches a year and their molars grow about 3 to 4 inches a year. Behind their upper incisors are the second incisors which are also called the peg teeth. Their form of prehension is to use their chisel-like incisors to cut vegitation and use their cleft upper lip which has sensitive vibrissae to feel what they are eating since they can not see directly infront of them. Their premolars and molars are tightly fit together to form one long grinding board to break down the vegitation. To help with the breaking down of the feed, the rabbit has four major pairs of salivary glands (parotids, mandibulars, sublinguals, and zygomatics).
After the break down of the feed, it is formed into a bolus and sent down the esophagus to the stomach. Just like horses, rabbits are unable to vomit which may cause problems if something is ingested that should not be.
The stomach of a rabbit is kept at a Ph of about 1 or 2 causing most microbial organisms to die off. Passage of food in the stomach is estimated to take 3-6 hours and during that time enzymes and HCL are secreted into the stomach to start the break down of the feed.
Small Intestine (Group 2 - Brooke F)
Large Intestine (Group 2 - Emily D)

Small Intestine (Group 2 - Abigail F)
The small intestine of a horse is about 70 feet long and holds around 48 quarts of feed stuffs. It is broken into three parts; the duodenum, jejunum and the ileum. Most abosorption of the nutrients occurs in the jejunum and the beginning of the ileum, but the duodenum also absorbs nutrients as well.
digestion. Panctreatic secretionssecretions, from the pancreatic ductduct, release liquid that"juice" which contains several zymogens (inactive enzymes)enzymes), pancreatic lipase, and pancreatic amylase. The two major zymogens are trypsinogen and chymotrysinogen. Trypsinogen is activated by enterokinase (lies in the intestinal mucosa) which then creates the enzyme trypsin. Now that trypsin is formed, it activates chymotrysinogen which then turns into the enzyme chymotrypsin. Trypsin and chymotrypsin both digest protiens into peptides, but are unable to break them down into single amino acids, but don't fret for there are other zymogens that digest protien as well including proelastase and procarboxypeptidase A and B (also activated by trypsin).
Pancreatic lipase breaks down fats (mainly triglyceride) into fatty acids able to be absorbed. Along with lipase, bile (mixture of salts, pigment, mucous, and cholesterol) is secreted from the liver to help break down fats and and suspend them in water. Bile is usually stored by the gall bladder, but since horses don't have one, bile is always being secreted into the small intestine.
Pancreatic amylase breaks down carbohydrates (glucose) from plants into maltose which is then able to be absorbed and used.
After the duodenum comes the jejunum which is responsible for most of the nutrient absorption. The jejunum has the most surface area because of villi (finger like projections) and micro villi on the villi them selves.
The ileum is really the last place for nutrient absorption before the mixture of broken down feed and pancreatic juices enter the large intestine.
(Cholesystokinin (CCK) is a hormone that is stimulated by fat and protien entering the duodenum which causes the pancreas to contract that leads to the feeling of being full)
Large Intestine (Group 2 - Brooke F)
Cecum- receives feedstuffs straight from the ileum. I is a blind pouch located at the junction of the small and large intestine (the cecum is part of the LI). Uses Microbial digestion of fibers mostly carbohydrates, which then produces volatile fatty acids. Within the cecum the synthesizing of Vitamins B and K occurs.

The stomach: Horses have a relatively small stomach for their size, and this limits the amount of feed a horse can take in at one time. The average sized horse (800 to 1,200 pounds (360 to 540 kg)) has a stomach with a capacity of around 4 US gallons. The horse stomach consists of a non-glandular proximal region (saccus cecus), divided by a distinct border, the margo plicatus, from the glandular distal stomach. In the stomach, assorted acids and the enzyme pepsin (which comes from which zymogen?) break down food. Pepsin allows for the further breakdown of proteins into amino acid chains. Other enzymes include resin and lipase. Additionally, the stomach absorbs some water, as well as ions and lipid soluble compounds. The end product is food broken down into chyme. It then leaves the stomach through the pyloric valve, which controls the flow of food out of stomach.
Small Intestine (Group 2 - Abigail F)
The small intestine of a horse is about 70 feet long and holds around 48 quarts of feed stuffs. It is broken into three parts; the duodenum, jejunum and the ileum. Most abosorption of the nutrients occurs in the jejunum and the beginning of the ileum, but the duodenum also absorbs nutrients as well.
Starting with the duodenum, this is the active site of digestion. Panctreatic secretions from the pancreatic duct release liquid that contains zymogens (inactive enzymes) that break down
Large Intestine (Group 2 - Brooke F)
Cecum- receives feedstuffs straight from the ileum. I is a blind pouch located at the junction of the small and large intestine (the cecum is part of the LI). Uses Microbial digestion of fibers mostly carbohydrates, which then produces volatile fatty acids. Within the cecum the synthesizing of Vitamins B and K occurs.

- Cows GREAT JOB, PERFECT AS IS :)
Pre-Small Intestine (Group 4 - Emily Nelsen)
Mouth – Cows have no upper incisors or canines, instead they have a dental pad. Only molars exist on the top of their mouth. They do have teeth in the front on the bottom, but those are for cutting and pulling. They bring feed into their mouth with their lips and tongue and chew it until it is fully mixed with the saliva (water, mucin, sodium bicarbonate, and salivary amylase) in which it forms a bolus.

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.
pancreatic enzymes (zymogens,(zymogens these are inactive enzymes, lipase, and 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
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.
by microbes. VMA’sVMFA’s are then microbial digestion, VMAVMF for fatty A synthesis, and
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.

Esophagus: The esophagus in a giraffe can complete two way peristalsis. This gives them the ability to regurgitate their food in the form of cud. Cud is then re-chewed and re-swallowed.
Stomach: The stomach of a giraffe is made up of 4 parts- reticulum, rumen, omasum, and abomasum. Being a ruminant, the giraffe also has a special reticular/esophageal groove.
down the food.food.Physical breakdown happens how? Microbes--what do they do, what byproducts do they produce?
Omasum: This particles by size.size.Water absorption
Abomasum: This protein peptin pepsin (an active
Reticular/Esophageal Groove: This is a special tube that closes of when in the presence of suckling and milk protein (may be triggered by other things as well, but it is still unknown). By having a closed tube it allows for the milk to bypass the rumen and enter directly into the omasum. It is normally found in young animals.
Small Intestine (Group 4 - Rose S)
Large Intestine and Post Large Intestine (Group 4 - Emily N)
and Rectum.
Cecum – The blind pouch at the junction of the small and large intestines. Microbial digestion of fibrous carbohydrates, synthesis of B and K-vitamins, and the production of Volatile Fatty Acids by microbes take place in the cecum. VFAs are used for energy and are absorbed through the cecal wall.
Colon – A giraffe’s colon (ascending) is part of a large distal fermentation chamber that is vital for their survival when they are browsing. The colon is made up of cuboidal and goblet cells, which secrete mucous. It has the same roles as the cecum, but has a slower rate of passage of material. Microbial digestion, VFA synthesis, and B and K-vitamin synthesis take place in the colon as well. The colon also is the site for water reabsorption and the concentration of feces.

Pre-Small Intestine (Group 3 - Teal K)
Pre- Small Intestine in pigs includes three different parts including the mouth, oesophangus, and the stomach:
& Oesophangus: This is the British spelling, we usually spell it esophagus, just FYI.
The mouth serves a valuable role not only for the consumption of food but it also provides for the initial partial size reduction though grinding. While teeth serve the main role in grinding to reduce food size and increase surface area, the first action to begin the chemical breakdown of food occurs when feed is mixed with saliva. There are three main salivary glands, which include the parotid, mandibular and sub-lingual glands. Saliva secretion is a reflex act stimulated by the presence of food in the mouth. The amount of mucus present in saliva is regulated by the dryness or moistness of the food consumed. Thereby in a dry diet, more saliva mucus is secreted while in a moist diet, only an amount to assist with swallowing is secreted. Saliva generally contains very low levels of amylase, the enzyme that hydrolyses starch to maltose. The contribution of digestive enzymes from saliva is minor but still noteworthy. Once food is chewed and mixed with saliva, it passes though the mouth, pharynx and then the oesophagus to the stomach. Movement though the oesophagus involves muscle peristalsis, which is the contraction and relaxation of muscles to move the food.
Stomach:
Small Intestine (Group 3 - Sarah L)
Some factors that can have an affect on the digestion and absorption in the small intestine of pigs are mode of ingestion, digestibility, and contact surface.
of materials. Most definitely. Any type of stress can reduce the surface area and functionality of the SI.
Pigs can have small intestines that reach up to twenty meters in length and can account for one-third of their whole gastrointestinal tract volume. Pigs (and other mammals) have a small intestine that consists of three parts: the duodenum, the jejunum, and the ileum. The small intestine also consists of multiple layers. One of these layers is called the epithelium, which contains villi (projections) that consist of intestinal cells called enterocytes. Connective tissue makes up another layer of the small intestine. Nerves, blood, and lymphatic vessels are all considered connective tissues. There is additionally a smooth muscle layer that aids in involuntary peristalsis. There is also an external layer, which provides support and protection.
The first portion of the small intestine is the duodenum. The duodenum can easily reach up to twelve inches in length in swine. This portion is the active site of digestion. This is where secretions from the pancreas are added from the pancreatic duct. These secretions contain some active enzymes and zymogens (inactive enzymes). The zymogen Trypsinogen is activated by Enterokinase, and activates it into Trypsin. The zymogen Chymotrypsinogen is activated by Trypsin and activated into Chymotrypsin. The zymogen Proelastase is activated by Trypsin and activated into Elastase. The zymogen Procarboxypeptidase A is activated by Trypsin and activated into Carboxypeptidase A. The zymogen Procarboxypeptidase B is activated by Trypsin and activated into Carboxypeptidase B. All of these enzymes digest protein.

Non-Ruminants - Mice
Pre-Small Intestine (Group 3 - Candace H)
small intestine. What about protein digestion? Pepsin.
Small Intestine (Group 3 - Teal K)
portal vein. More info, please. Zymogens, enzymes, micelles, etc. See the dog's SI for good example.
Large Intestine (Group 3 - Sarah L)
The large intestine in the mouse (and all other mammals) is made up of the cecum, colon, and rectum. These three portions share the same wall structure, which consists of the innermost layer, which is known as the mucosa, which is surrounded by the submucosa. The submucosa is surrounded by the muscularis interna and externa layers. The muscularis interna and externa layers are surrounded by the outermost layer, which is known as the serosa. The mucosa of the large intestine is comprised of simple columnar epithelium and lamina propria. The lamina propria is a constituent of the moist linings known as mucous membranes or mucosa, which line various tubes in the body, as in this case, the large intestine.
us humans do).do) the hypothesis is that humans' appendix was a cecum at some point a long time ago. so the mouse has a cecum therefore would not have an appendix. The mucosa
The next part of the mouse’s large intestine, the colon, is made up of cuboidal cells and Goblet cells. Goblet cells in the colon secrete mucous, which is very important because it helps protect the colon and acts as a transportation aid when all the undigested, fibrous material that didn’t get absorbed by the small intestine travels through the large intestine. Also, the colon contains no villi, so not much of anything is being absorbed. The colon has all the same funtions of the cecum, so Volatile Fatty Acids are produced, B-vitamins are being synthesized, and microbial digestion is occurring. Water reabsorption and fecal concentration also take place in the colon.
The last part of the mouse’s large intestine is known as the rectum. Here, feces form from undigested material. Some of this material includes, sloughed bacteria, dead cells, fluid, and unabsorbed feedstuffs. The mouse’s rectum partly determines the shape and size of the mouse’s feces. In the mouse, the rectum is particularly short. The mucosa and submucosa of the rectum form longitudinal folds. The rectum has a well-developed muscularis mucosae, a thick muscularis interna, and a thin muscularis interna.
Post Large Intestine (Group 3 - Ashley G)
exit of feces.feces.The rectum is part of the LI so this part would only be the anus.

Pre-Small Intestine (Group 3 - Ashley Gille)
Dog- pre-small intestine
way of peristalsis.peristalsis.--Excellent description :)
Small Intestine (Group 3 - Candace Hoelzel)
of the way.way (more specifically, which zymogens and enzymes and how are they activated?). Moving on
Large Intestine (Group 3 - Teal Kampe)
for a walk.walk.LOL
The large and anal canal.canal - nope, this belongs in the alimentary tract.. However, the
Post Large Intestine (Group 3 - Sarah Luing)
the stool. Cool method, not so cool if they're infected, lol.