1. Animal Digestion

2. Objectives
Identify the various types of digestive systems found in animals.
Identify the major parts of the digestive system and describe their functions.

3. Terms abomasum absorption amino acids anus avian digestive system bile
cecum
chyme
crop
cud
digestion
digestive system
enzymes
eructated
feces
gizzard

4. Terms intestinal juice monogastric digestive system omasum organs
pancreatic amylase
pancreatic juice
pepsin
pseudo-ruminant digestive system
reticulum
rumen
ruminant
ruminant digestive system

5. Terms rumination salivary amylase salivary maltase stomach trypsin
villi

6. What are the various types of digestive systems found in animals?
Digestion __________________________________________________________________________________
Absorption is the process of taking the digested parts of food into the bloodstream.

7. What are the various types of digestive systems found in animals?
The digestive system consists of the parts of the body involved in chewing and digesting food.
There are four basic types of digestive systems:
____________________
_________________

8. What are the various types of digestive systems found in animals?
A. The ___________________________, or simple digestive system, contains a single-chambered stomach and is the type found in humans, swine, dogs, and cats.
The__________is a muscular organ that stores ingested food and moves it into the small intestine.

9. What are the various types of digestive systems found in animals?
The stomach secretes acid that has a low pH of ___________.
________________________________________________________________________________
Animals with this type of digestive system are better adapted to the use of concentrated feeds, such as grains, than to the use of large quantities of roughages.

10. What are the various types of digestive systems found in animals?

11. What are the various types of digestive systems found in animals?
B. The ruminant digestive system, or ____________________________, contains one large stomach divided into four compartments and is the type found in cattle, sheep, and goats.

12. What are the various types of digestive systems found in animals?
______________________________________________________________________
Due to the complexity of its digestive system, a ruminant can make good use of roughages.
____________ percent of the roughages fed are digested.
The compartments of the stomach, in the order of digestion, are:
rumen
reticulum
omasum
abomasum

14. What are the various types of digestive systems found in animals?
1. The_______is the largest section of the stomach and the first compartment that the food enters.
It accounts for approximately percent of the stomach.
________________________________________________________________________________
The rumen is designed so that food can be ingested, eructated (belched up), chewed, and then swallowed again.

15. What are the various types of digestive systems found in animals?
2. The _____________is the second segment of the stomach.
It is sometimes considered an extension of the rumen.
_____________________________________
It aids in keeping the food in the rumen mixed with water and saliva until it is the right consistency.

16. What are the various types of digestive systems found in animals?
3. The __________ is a small compartment that is the main sight for water absorption.
The particles are squeezed and dehydrated, as well as sorted.
___________________________________________________

17. What are the various types of digestive systems found in animals?
4. The _______________, or “true stomach,” is the site of digestion.
It secretes gastric juices consisting of ____________________________________
These juices kill and then digest the microbes that have passed with the food materials from the rumen.
________________________________________________________________________________

18. What are the various types of digestive systems found in animals?
C. The _____________________________
is the type found in animals that eat large amounts of roughages but do not have stomachs with several compartments.
This type of digestive system performs some of the same functions as the type found in ruminants.

19. What are the various types of digestive systems found in animals?
A pseudo-ruminant can utilize large amounts of roughages because of its greatly enlarged cecum and large intestine.
________________________________________________________________________________
___________________________________________________________________

21. What are the various types of digestive systems found in animals?
D. The ____________________________ is the type found in poultry.
This system differs greatly from any other type.
Since a bird has no teeth, no chewing is involved.
_____________________________________________________________

22. What are the various types of digestive systems found in animals?
The _________ is where the food is stored and soaked.
From the crop, the food makes its way to the gizzard.
The _________ is a very muscular organ, which normally contains stones or grit that grinds the food.
__________________________________________________________________

24. What are the major parts of the digestive system and their functions?
The digestive system is made up of a number of ________, which are parts that perform specialized functions.
The digestive system begins at the mouth, where food enters the body, and continues to the anus, where undigested material exits the body.

25. What are the major parts of the digestive system and their functions?
A. ________________________—The chewing action of the mouth and teeth breaks, cuts, and tears up the food.
This increases the surface area of the food particles and aids in the swallowing process.
Saliva not only stimulates the taste of the food but also contains the enzymes _____________________________________.

26. What are the major parts of the digestive system and their functions?
_____________are organic catalysts that speed up the digestive process.
________________changes starch to maltose, or malt sugar.
____________________changes maltose to glucose.
Chewed food passes from the mouth to the stomach through a muscular tube called the esophagus.

27. What are the major parts of the digestive system and their functions?
B. ______________________________________________________________________________________
The fluids come from glands in the wall of the stomach.
The juices contain from 0.2 to 0.5 percent hydrochloric acid.
This acid stops the action of the amylase from the mouth.

28. What are the major parts of the digestive system and their functions?
The gastric juices also contain the enzymes pepsin, rennin, and gastric lipase.
_______________________________________________________________________________.
The muscular walls of the stomach churn and squeeze the food.
________________________________________
The gastric juices then act on the solids that remain in the stomach.

29. What are the major parts of the digestive system and their functions?
C. Ruminant stomach—The four parts of the ruminant stomach are rumen, reticulum, omasum, and abomasum.
_______________________________________________________________
______________________________________________________________
The solid part of food goes into the rumen.

30. What are the major parts of the digestive system and their functions?
The liquid part goes into the reticulum, then into the omasum, and on into the abomasum.
In the rumen, the solid food is mixed and partially broken down by bacteria.
________________________________________
The food is then forced back into the mouth, and rumination occurs.
________________________________________________________________________________

31. What are the major parts of the digestive system and their functions?
On average, cattle chew their cuds about six to eight times per day.
_____________________________________________________________
The rumen and the reticulum contain millions of bacteria and protozoa.
It is the bacterial action in the rumen that allows a ruminant to use large amounts of roughage.
________________________________________________________________________________

32. What are the major parts of the digestive system and their functions?
_________________are compounds that contain carbon, hydrogen, oxygen, and nitrogen.
______________________________________________________.
Bacteria also produce many of the vitamins needed by the animal.

33. What are the major parts of the digestive system and their functions?
D. Small intestine—The partly digested food that leaves the stomach enters the small intestine as an acidic, semifluid, gray, pulpy mass.
__________________________
In the small intestine, the chyme is mixed with three digestive juices: ________________________________________________________________.

34. What are the major parts of the digestive system and their functions?
1. ______________________, secreted by the pancreas, contains the enzymes trypsin, pancreatic amylase, pancreatic lipase, and maltase.
________________________________________________________________________________

35. What are the major parts of the digestive system and their functions?
Proteoses are the most complex compounds, and peptides are the simplest.
___________________________changes starch in the food into maltose.
Sugar and maltose are broken down even further by maltase.
They are then changed into a simple sugar called glucose.
________________________________________________________________________________

36. What are the major parts of the digestive system and their functions?
2. ________________________________________________________
Bile is stored in the gallbladder in all animals except the horse.

37. What are the major parts of the digestive system and their functions?
3. Glands in the walls of the small intestine produce ________________________.
Intestinal juice is a fluid that contains peptidase, sucrase, maltase, and lactase, all enzymes used in digestion.

38. What are the major parts of the digestive system and their functions?
E. Cecum—The cecum, or “blind gut,” is found where the small intestine joins the large intestine.
______________________________________________________________
In a pseudo-ruminant, the roughages consumed are digested by the bacterial action in the cecum.

39. What are the major parts of the digestive system and their functions?
F. Large intestine—The main function of this organ is to absorb water.
_______________________________________________________________________________.
The key to absorption in the large intestine is the small fingerlike projections on the walls, called villi.

40. What are the major parts of the digestive system and their functions?
Food materials not digested or absorbed are called feces.
These materials are moved through the large intestine by muscles in the intestinal walls.
The undigested part of food is passed out of the body through the anus, the opening at the end of the large intestine.

41. Review
What are the various types of digestive systems found in animals?
What are the major parts of the digestive system and their functions?