1. The Equine Digestive System Presentation Part 3: Anatomy of the Digestive System (Continued) #8895-A

2. Small Intestine 2 inch by 60 foot tube Holds approximately 12 gallons Connects stomach to large intestine Contains three parts: the duodenum, the jejunum, and the ileum

3. Small Intestine 30% of the digestive tract Folded into many loops and coils 2.5 to 4 hours for feed to pass

4. Small Intestine Bloodworms cause blood clots may result in colic or death tend to lodge in the mesentery artery which supplies blood to the intestines

5. Small Intestine Small intestine and accessory organs, the pancreas and liver, supply enzymes Peristalsis mixes fluid contents of the which are about 92-95% water Pancreatic juices contain the enzymes trypsin, pancreatic lipase, and amylase

6. Small Intestine Trypsin - converts proteins into amino acids which the small intestine absorbs Primary site of protein digestion and absorption of amino acids Pancreatic lipase - breaks down fats to glycerol and fatty acids

7. Small Intestine Liver secretes bile – helps break down fat – aids in fatty acid absorption – activates pancreatic lipase Most soluble carbohydrates digested in small intestine

8. Small Intestine End products of carbohydrate digestion are glucose and volatile fatty acids which are absorbed for energy Absorbs nutrients, such as simple sugars, fatty acids, amino acids, minerals, and vitamins

10. Large Intestine Composed of the cecum, large colon, small colon, and rectum Moves undigested materials from small intestine to anus for elimination 50-60% of digestive tract

11. Large Intestine Holds 30-35 gallons 25 feet long Designed for utilization of plant fiber for energy

12. Large Intestine After ingesta leaves small intestine, it enters into cecum – substances that have been taken into the body by way of the digestive tract Cecum serves as fermentation vat in which enzymes break down fibrous plant structures for digestion

13. Large Intestine Carbohydrates such as cellulose that escaped digestion in small intestine are fermented in large intestine – Complex carbohydrate that is the main component of the plant cell wall

14. Large Intestine Can digest cellulose, starch, & sugars into volatile fatty acids – supplies up to 25% of horse ’ s energy

15. Large Intestine Cecum - primary site of water absorption Rate of passage slower than in other portions of digestive tract 36-48 hours

16. Rectum Connects small colon to anus Receives feces small colon has formed into characteristic balls Forty to fifty pounds of feces is voided eight to twelve times a day

17. Rectum Shape, size, and consistency of feces give clues to overall health Dry and hard - lack of water or protein Too soft - Sick or eating diet that is too laxative