An overview of nutrients

1. An overview of nutrients

2. Nutrients • Carbohydrates • Proteins • Lipids • minerals • vitamins • water

3. Dry Matter • Organic compounds: • Carbohydrates • Lipids • Proteins • Nucleic acids • Vitamins • Organic acids • 2.Inorganic Compounds: • - Minerals

4. Proximate Analysis • Moisture • Ash • Crude Protein • Ether Extract • Crude Fiber Nitrogen Free Extract (NFE): Calculated

5. Proximate Analysis Dried Sample Kjeldahl (CP) Ether Extraction (EE) Fat Free Residue Boil in acid Ash Boil in alkali CF Crude Fiber + Ash

6. Crude Fiber • Mono-gastric Animals …… • Ruminant Animals …..? Detergents • NDF (cell wall contents): gut fill • ADF (NDF minus H-cellulose): digestibility • ADL ???

7. Carbohydrates • Primary component of livestock feed • Renewable resource as they are converted to CO2 and H2O. • Primary carbohydrate in plants is glucose • Comprise 70% of forage dry matter and 80% of concentrates • Carbohydrates are a source of energy but there is no specific requirement for them

8. Carbohydrates • Carbon, hydrogen, oxygen • Monosaccharide five pentose or six carbons hexose. • Disaccharides, polysaccharides Starch

9. Carbohydrates • Sugars: Mono (# C) : C3, C4, C5, C6, C7 Pentoses: Ribose; Hexoses: Glu, Gal, Man, and Fru Disaccharides: Sucrose, Lactose, Maltose Tri: Raffinose, Kestose Tetra: Stachyose

10. Carbohydrates Polysaccharides Non- Sugars Heteroglycans Arabinans Xylans Glucans Homoglycans Pectic Substances Hemicellulose Gums Chondroitin Starch, Dextrin, Glycogen, Cellulose Complex Carbohydrates Glycolipids Glycoproteins

12. Lipids • General • Soluble in ether • Contain Carbon, Hydrogen and Oxygen C, H, O • High proportion of carbon and hydrogen • ~2.25times the energy of carbohydrate per gram

13. Lipids • Classification • Simple • True fat - esters of glycerol • Waxes - esters of other alcohols • Classification • Compound - groups other than alcohol and FA's • Phospholipids - phosphoric acid and nitrogen • Glyco-lipids - Carbohydrates and nitrogen • Lipoproteins- proteins and lipids

14. Lipids Glycerol-based Non Glycerol-based Complex Simple Phosphoglycerids Waxes Steroids Terpens Sphingomyelin Prostaglandins Fat/ Oil Glycolipids Lecithin Cephalin Galactolipids Glucolipids

15. Lipids • Classification • Derived lipids • Fatty acids • Sterols • Fats and Oils • Fat vs Oil - Melting point only difference • Fat = glycerol + 3 fatty acids

16. Lipids

17. Lipids • Characteristics of fat due to type and proportion of different fatty acids • Chain length • Longer chains result in higher melting points. • Butyric C4H8O2 • Palmitic C16H32O2 • Stearic C18H36O2

19. Examples: Fatty acids • Oleic C18:1 • CH3-(CH2)7-CH=CH-(CH2)7-COOH • Linoleic C18:2 • CH3-(CH2)4-(CH=CH-CH2)2(CH2)6-COOH • Linolenic C18:3 • CH3-CH2-(CH=CH-CH2)3(CH2)6-COOH • Arachidonic C20:4 • CH3(CH2)4(CH=CHCH2)4(CH2)2COOH

20. Lipids • Iodine number-A measure of un-saturation. • Saponificationnumber-A measure of chain length. The amount of alkali required to saponify 100 grams of fat. • Other lipids: Sterols • Cholesterol. Mainly in animal tissues. • Hormones. Very little quantitatively. • Ergosterol. A sterol in plants which can form vitamin D through the action of ultra violet light

22. Other lipids • Carotenes. • Yellow colored substances common in plants that can be converted by animals to vitamin A. • Phospholipids. • Most abundant in blood, brain, liver and egg yolk. Can be utilized.

23. β-carotene Phospholipids

24. Other lipids • Chlorophyll • Green colored substance in plants - No feed value for animals. • Waxes • Surface of leaves and fruits. • Essential oils. • Give plants their odors and tastes.

25. Proteins • Long chains of Amino Acids. • Contain Nitrogen, carbon, hydrogen, oxygen, and sometimes sulphur. • Lose tertiary structure when heated.

26. Proteins • Globular • Fibrous • Conjugated Amino acids • Indispensable • Dispensable • Structural • Transporter • Catalytic Totally C-skeleton Traditionally Indispensable Conditional Acquired dispensable Immaturity Disorders AA intake Newer Definition Human Nutrition

29. Other N compounds • Non protein Nitrogen (NPN) • Urea • Nucleic acids • DNA • RNA

30. Additives • Not as nutrients Some examples • Antibiotics: growth stimulator/ disease control • Anti-parasitic drugs • Synthetic Antioxidants • Antifungal agents • Enzymes: improved digestion

31. Digestion

32. Primary Enzymes for Carbohydrates • Ruminants do not secrete much sucrase • Inducible enzymes • Lactose intolerance

33. Primary Enzymes for Proteins

34. Primary Enzymes for Lipids

35. Nutrient Digestion - Lipids Large Lipid Droplet Action of bile salts Lipid emulsion Small Bile salts & pancreatic lipase and colipase Water soluble micelles

36. Digestion of Lipid • Bile salts emulsify lipids • Pancreatic lipase acts on triglycerides • Triglycerides sn-2 Monoglyceride + 2 fatty acids • Pancreatic colipase • Activated by trypsin • Interacts with triglyceride and pancreatic lipase • Displaces bile • Improves activity of pancreatic lipase

37. Importance of Pancreas for Digestion • Produces enzymes responsible for • 50% of carbohydrate digestion • 50% of protein digestion • 90% of lipid digestion • Produces bicarbonate for neutralization of chyme in duodenum

38. Digestive enzymes; summary