Daily Food for Thought

1. Daily Food for Thought What does the word ruminant mean to you?

2. In Groups of Four, See Which Group Can Solve this Puzzle in 5 minutes Abomasum Esophagus Mouth Omasum Reticulum Rumen Small Intestine

4. Monogastric Digestive System Trace Mouth Esophagus Stomach Duodenum Jejunum Ileum Cecum Colon Rectum Anus

5. Ruminant Digestive Systems Learning Target: I can trace the parts of the ruminant digestive system and describe the functions of each.

6. The Ruminant Digestive System

7. Ruminant Digestive Systems • Functions of the digestive system of animals include: • ingestion (eating) • chewing (mastication) • swallowing (deglutition) • absorption of nutrients • elimination of solid wastes (defecation)

8. Ruminant Digestive Systems • The digestive system changes food nutrients into compounds that are easily absorbed into the bloodstream.

9. Ruminants • 2.8 billion domesticated ruminants • ?

10. Work with the person next to you and brainstorm How many ruminant animals can you name?

11. Ruminants • 2.8 billion domesticated ruminants • Cattle, sheep, deer, elk, bison • Pregastric fermentation • Ability to chew cud at frequent intervals distinguishes true ruminant from other foregut fermenters • Kangaroo, colobine monkey are not true ruminants • Four compartment stomach • Reticulum • Rumen • Omasum • Abomasum

12. Ruminant Digestive Systems • Different species of animals have digestive systems adapted to the most efficient use of the food they consume. • The anatomy and physiology of the digestive systems of herbivores, carnivores, and omnivores all differ.

13. Ruminant Digestive Systems • Ruminants are those animals that contain a multi-chambered digestive system (polygastric) that allows the animal to gain the majority of their nutritional needs from forages and other roughages. • Forage refers to grasses, roughages refers to other high-fiber food sources.

14. Working in your pairs, brainstorm What items would be considered roughages?

15. Label the following Ruminant Digestive System 1. • Esophagus • Rumen • Reticulum • Omasum • Abomasom • Small Intestine • Cecum • Large Intestiine • Rectum 2. 3. 4. 7. 5. 9. 8. 6.

16. Daily Food for Thought Trace or list the parts of the ruminant digestive system

17. Ruminant Digestive Systems • The length and complexity of the digestive system depends on the species. • In herbivores, it is very long and complex.

18. Pancreas Pharynx Rectum Ruminant Digestive Systems Kidney Liver Esophagus Cecum Teeth Picture of digestive system of cow Anus Tongue Colon Reticulum Salivary Gland Rumen Small Intestine Omasum Abomasum

19. Ruminant Digestive Systems • The digestive system of ruminant animals includes the : • Mouth - grasps the food • Teeth - grind the food • Ruminants have only one set of teeth in the front of the mouth (incisors), and two sets in the back (molars).

20. Ruminant Digestive Systems • Tongue - covered with finger-like projections (papillae) that contain taste buds. • Salivary glands - secrete saliva, that moistens food and is mixed with the food material to aid in swallowing.

21. Ruminant Digestive Systems • Pharynx - funnels food into the esophagus, preventing food material from entering the lungs. • Esophagus - food tube that leads from the mouth to the stomach.

22. Ruminant Stomach Anatomy: • Reticulum • Rumen • Omasum • Abomasum

23. Ruminant Digestive Systems • At this point, ruminant animals have a multi-chambered “stomach” • Reticulum - honeycomb-like interior surface, this part helps to remove foreign matter from the food material.

24. Reticulo-rumen Although structurally they appear as a single continuous compartment, functionally they are distinctly different

25. Reticulum - full

26. Reticulum - cleaned

27. Reticulum • Honeycomb lining • No secretions • Formation of food bolus • Regurgitation initiated here • Collects hardware (nails, wire)

28. Ruminant Digestive Systems • Ruminant animals grasp mouthfuls of food and swallow it before it is chewed. • They wrap their tongue around a mouthful of grass, clamp down their teeth, and pull to break the grass at its weakest point, and swallow.

29. Ruminant Digestive Systems • Ruminants will“chew their cud” (regurgitate) their food material and then grind it with their molars at a time when the animal is resting. • This is done until the food particles are small enough to pass through the reticulum into the rumen.

30. Ruminant Digestive Systems • Since ruminant animals do not “chew” their food when it is taken in, at times foreign material like rocks, nails, small pieces of wire, can be swallowed.

31. Ruminant Digestive Systems • While the animal is “chewing its cud” foreign particles that are heavy are allowed to “sink” in the reticulum, preventing many foreign particles from entering the rest of the digestive system. • Once foreign material enters the reticulum, it stays there for the life of the animal.

32. Ruminant Digestive Systems • If enough of this foreign material remains in the reticulum, it may cause damage and infection of the reticulum (hardware disease).

33. Telephone Cord

34. Wire

35. Sponge taken from digestive system of an animal

36. Daily Food for Thought What are the compartments of the ruminant stomach?

37. Ruminant Digestive Systems • Rumen - the organ that allows for bacterial and chemical breakdown of fiber. • The rumen has a very thick, muscular wall. • It fills most of the left-side of the abdomen

38. Ruminant Digestive Systems • The walls of the rumen contain papillae (that can be up to 1 cm. in length), where the bacteria that are used to breakdown fiber live. • In some ruminants (dairy cattle) the rumen can have a capacity of 55-65 gallons!

39. Rumen • Digestion and fermentation vat • 40-50 gallons • No secretions • Contains anaerobic microbes (25-50 billion bacteria/mL fluid) • Also protozoa, fungi • Produce VFA, protein • Papillae lining • Increase surface area • Absorption of VFA • Passive diffusion

40. Papillae in Rumen

41. Papillae in Rumen

42. Ruminant Digestive Systems • Omasum - section that is round and muscular. • “Grinds” the food material and prepares the food material for chemical breakdown.

43. Omasum • Laminae/manyply lining • Muscular folds • No secretions • Reduces particle size • Absorption of water • ~60% removed • Absorption of VFAs • ~2/3 of VFAs entering or 10% of total produced • Prevents buffering of the abomasum

44. Omasum - full

45. Ruminant Digestive Systems • Abomasum - very similar to the stomach of non-ruminants. • this is where the majority of chemical breakdown of food material occurs. • mixes in digestive enzymes (pepsin, rennin, bile, etc.).

46. Abomasum – inside view

47. Ruminant Digestive Systems • Small Intestine - where most of the food material is absorbed into the bloodstream • Contains three sections: • duodenum • jejunum • ileum

48. Ruminant Digestive Systems • The food material is continually squeezed as it is moved through the small intestine, becoming more solid. • The majority of the food material absorption occurs in the duodenum and the jejunum.

49. Ruminant Digestive Systems • Large Intestine - begins to prepare unused food material for removal from the body • a portion of the large intestine in some animals contain pouches that may contain enzymes for further species-specific digestion (horses and rabbits (cecum)).

50. Large Intestine • Fermentative digestion • Bacteria similar to rumen, but no protozoa • Digestion in colon may account for as much as: • 27% of cellulose digestion • 40% of hemicellulose digestion • 10% of starch digestion • Only important in conditions that increase the amount of fermentative carbohydrate entering the large intestine • Increased rate of passage of forages • High grain diets • May account for as much as 17% of total VFA absorption • VFAs are efficiently absorbed, but primarily used as energy source for large intestinal mucosa cells