Note Taking Guide Topic # 3045 Digestion/Absorption By: Alisa Amy Kowalski Ruminant ● An animal with 4 distinct compartments in its stomach, which swallows its food essentially un-chewed, regurgitates it, chews it thoroughly and re-swallows it. ○ Examples: _______________________________________________________ Nonruminants (Monogastrics) ● An animal having a single compartment in its stomach, which swallows its food after chewing and does not regurgitate it. ○ Examples: _______________________________________________________ Ruminant Stomachs ● The four compartments are ○ __________________ - honeycomb -5% ○ Rumen - _________________ -80% ○ ___________________ - manypiles -7% ○ Abomasum - ___________________ -8% Reticulum ● Nickname - “____________________ stomach” ● Furnishes additional ___________________ space ● Holds foreign material to prevent damage to other internal organs ○ Examples: _______________________ ● A _____________ may be fed to ruminants to catch and hold this foreign materials in the reticulum Rumen ● Largest compartment ○ Capacity of __________ gallons in mature cattle ● Serves as a storage area ● Does not develop in young until __________ food is ingested by the animal Bacterial Action in Rumen ● Reason why ruminants can digest large quantities and live on a much lower protein diet than ______________________. ● As the bacteria multiply they make protein to construct their own bodies called bacterial protein. ● ● ● The bacterial protein is digested later in the stomach (abomasum) and the intestines of the ruminant Ruminants are able to consume a lower_____________________________ of dietary protein. The bacteria make up for it by multiplying and making protein from non-protein sources. Omasum ● Muscular section that _________________ the water from the feed before it enter the abomasum Abomasum ● “_______________________” ● Digestive juices containing enzymes cause chemicals changes to break down the proteins, carbohydrates, and fats into simpler substances, which can pass into the small intestine for further digestion and absorption into the blood stream. Regurgitation ● During the process of eating ruminants chew their feed just enough to make swallowing possible. ● After ruminants have consumed their feed, a bolus (food ball) is brought up form the rumen and chewing is completed. ○ __________________________ Non-Ruminant Digestion ● Food is swallowed directly into the single compartment stomach, where it is mixed with the digestive juices. ○ Contains enzymes to break down foodstuffs ● Very little bacterial action ● No _______________________ of low quality protein to high quality protein ● Monogastrics are unable to digest large quantities of fiber unless they have an enlarged cecum ● Animals with an enlarged cecum ○ Sometimes called _____________________ ○ Examples: ________________, rabbits, and guinea pigs Non-Ruminant Digestion- Cecum ● Blind pouch at the first portion of the large intestine. ● Main place for_________________________________ in horses and rabbits Digestion & Absorption by Livestock ● ___________________________- the process by which large, complex food molecules are broken down into simpler molecules within the digestion system to prepare them for absorption and use by the body Digestion & Absorption by Livestock - Enzymes ● ● Organic compounds, which bring about changes in other organic compounds without themselves being changed or _____________________________. Break down complex feeds into simpler forms through chemical reactions Importance of Chewing ● Chewing- physical process of breaking down foodstuffs to smaller _________________. ● Increasing of _________________________ allow greater area for enzymatic activity Digestion of Carbohydrates ● Must be broken down into simple starches and sugars before they can be absorbed in the ___________________________. ● Begins in the mouth in animals whose saliva contains the enzyme ______________________ (non-ruminants). ○ Begins in ___________________ in animals without ptyalin ● The rest is digested and absorbed in the small _______________________. ● Millions of bacteria and protozoa grow in the mass of water and feed in the rumen. ○ Secrete enzymes which digest the carbohydrates and proteins ○ Reproduce and grow using the digested material, primarily the _____________________ Bacterial Digestion of Carbohydrates ● During this process they also synthesize B vitamins ○ Used in the ______________________ system & to release energy from digested nutrients in the host animal ● Because of this adult ruminants do not need dietary ______ vitamins ● Small amount of the digested cellulose and other carbohydrates is incorporated into the rumen “organisms” ● Most is converted into organic acids ○ ________________________________ (VFAs) ○ Acetic, propionic and butyric ○ Absorbed directly through the rumen wall into the capillaries of the circulatory system. ● Similar activities occur in the cecum of the horse and rabbit ○ Horses have little need for B vitamins due to this ● Relationship between the rumen protozoa & bacteria and the host (or ruminant) is called ______________________. ● Way in which two organisms of two different species live in intimate association with each other Relationships Between Organisms ● ____________________ - each helps the other ○ Example: man and dairy cow ● ____________________ - one benefits, the other does not ● ● ○ Example: Sheep tick on a sheep ____________________ - one depends on the other for some essential food factor, often detriment to host ○ Example: leech on fish Phoresis - the host _____________________ the symbiont ○ Example: barnacle on a whale Protein Digestion ● Broken down into ______________________ (smaller units) and __________________ (building blocks of proteins) in the stomach or abomasum of ruminants ● Begins in stomach with pepsin ○ Enzyme found in the _____________________________ ● Final digestion in the small intestine where absorption also occurs Fat Digestion ● Do not undergo digestion until they reach the _________________________ ● Bile and enzymes from the pancreas help in the breakdown of fats so they can be absorbed in the small intestine. Villi ● ● Line the intestines and are minute ________________________ projections or papillae Provide a larger surface are in the lining of the intestine so there is more surface area for absorption of nutrients Distribution of Nutrients ● Most nutrients are absorbed by the villi in the small intestine and enter the circulatory system ● The blood, containing these nutrients, reaches the ______________________ in all the body tissues ● Here the nutrients pass through the capillary wall into the __________________ (clear fluid occupying the space between the cells). ● The nutrients then enter the cells, providing nourishment and energy for the various life processes