2. Digestive System Jr/Sr Veterinary Science Mrs. Chotkowski #1

3. Functions Intake & digestion of food Absorption of nutrients Elimination of solid waste products

4. Structures Oral cavity & pharynx Esophagus Stomach Small Intestines Large Intestines, rectum, anus

5. Oral Cavity (Mouth) Lips: responsible for ingestion Prehension: Grasping of food Tongue: organ which tastes food; contain papillae (bumps & ‘taste buds’) Mastication: Breaks food into pieces with saliva Teeth: grind food –Deciduous dentition: temporary ‘baby’ teeth –Permanent dentition: adult teeth

6. Esophagus Collapsible, muscular tube; brings food to the stomach Peristalsis: waves of muscle contraction that move food through the digestive tract

7. The Stomach Stores food, begins digestion Monogastric (Simple Stomach): –Humans, pigs, dogs, cats Monogastric w/ a functional cecum: –Horses, rabbits Ruminant (four compartments): –Cattle, sheep, goats (chew cud)

8. Monogastric (Dog)

9. What are the parts A – G ?

11. Monogastric w/ Functional Cecum

12. Ruminant

14. Digestive Juices Saliva (mouth); lubricates feed, contains amylase, which breaks down starch Bile (liver); helps break down fat Intestinal juices: contain enzyme peptidase, to break down proteins, & maltase, sucrase, & lactase to break down sugars

15. Gastric Juices HCl: stops action of amylase Pepsin: enzyme, digests proteins Rennin: enzyme, digests milk protein Lipase: enzyme, digests fats Mucus: protects stomach lining Gastrin: stimulates stomach to produce more juices

16. Pancreatic juices Lipase: breaks down fats Trypsin: Breaks down proteins Chymotrypsin: acts on proteins Amylase: works on starch

17. Ruminant Digestion Rumen: largest compartment, serves as a fermentation vat Reticulum: honeycomb, helps filter feed Omasum: contains papillae that help grind food Abomasum: true stomach, secretes gastric juices, starts protein digestion

18. Small Intestine Duodenum: first portion, continues digestion Jejunum & Ileum: rest, performs absorption of nutrients into the bloodstream

19. Large Intestine Cecum: enlarged first portion, contains micro-organisms, fermentation vat Colon: absorbs water and forms feces Rectum: carries feces to the anus Anus: passes solid wastes out of body

20. The End