Veterinary Biochemistry Lecture 2 Nutrition 1 PDF

VETM 1503:VETERINARY BIOCHEMISTRY LECTURE # 2: NUTRITION 1 Dr. Kavita R. Lall, B.Sc. (Hons.), D.V.M. (Hons.), M.Sc. (Dist.) OUTLINE  Learning objectives  Introduction  Macronutrients  Micronutrients  Essential nutrients LEARNING OBJECTIVES  Under...

VETM 1503:VETERINARY BIOCHEMISTRY LECTURE # 2: NUTRITION 1 Dr. Kavita R. Lall, B.Sc. (Hons.), D.V.M. (Hons.), M.Sc. (Dist.) OUTLINE  Learning objectives  Introduction  Macronutrients  Micronutrients  Essential nutrients LEARNING OBJECTIVES  Understand the importance of nutrition  Describe the components of the diet in terms of macro and micronutrients and understand their roles  Explain the term and roles of essential nutrients  Discuss the results of inadequate dietary intake of micronutrients (vitamins) INTRODUCTION  Nutrition ◦ Integrative science ◦ Deals with the different steps by which an animal assimilates food and uses it for its growth, health and performance  Meat  Milk  Egg INTRODUCTION CONT’D  Nutrients ◦ Chemical elements or compounds present in feed that support health, growth, basic body maintenance, productivity and reproduction INTRODUCTION CONT’D MACRONUTRIENTS  Provide the body with energy and the components it needs to maintain its structure and functions  Required in larger amounts and larger quantities than other nutrients ◦ >10 g/day MACRONUTRIENTS CONT’D  Carbohydrates ◦ Carbon, hydrogen, oxygen ◦ Includes sugars, starch, cellulose ◦ Provides energy ◦ In excess, converted into body fats MACRONUTRIENTS CONT’D  Proteins ◦ Carbon, hydrogen, oxygen, nitrogen ◦ Amino acids ◦ Diverse structure and function ◦ Required for growth and repair MACRONUTRIENTS CONT’D  Lipids ◦ Carbon, hydrogen, oxygen ◦ Concentrated source of energy  2.25 x more energy than carbohydrates ◦ Form cholesterol, steroids ◦ Provide energy reserves, protection for organs and insulation MICRONUTRIENTS  Required in smaller quantities (micrograms, milligrams)  Central role in metabolism and maintenance of tissue function MICRONUTRIENTS CONT’D  Vitamins ◦ Complex, organic substances ◦ Function in different metabolic processes  Enzyme precursors  Co-enzymes ◦ Some vitamins need to be provided to the animal through diet  Some can be synthesized by the rumen and hindgut microbes or by exposure to sunlight  Humans, non-human primates and guinea pigs need dietary Vitamin C VITAMIN A VITAMIN D * Calcitriol is the most metabolically active form of vitamin D VITAMIN E  VITAMIN K Vitamin K1 is found in green plants (phylloquinones) Vitamin K2 (menaquinones) is synthesized by hindgut bacteria The liver converts vitamin K1 and K3 to K2 before it is used The metabolically active form of vitamin K is menaquinones B-COMPLEX VITAMINS VITAMIN C MICRONUTRIENTS CONT’D  Minerals ◦ Inorganic elements that are essential for the body’s physiological functions and metabolic processes ◦ Required in minute quatities ◦ Hundreds ◦ Macrominerals - occur in appreciable amounts in the body and are required in larger quantities in the diet (> 0.01%) ◦ Microminerals are required in trace amounts (< 0.01%), in milligrams, micrograms or parts per million  MICRONUTRIENTS CONT’D  Macrominerals  Microminerals  Iron  Calcium  Zinc  Phosphorus  Copper  Manganese  Potassium  Iodine  Sulphur  Selenium  Sodium  Chloride  Functions:  Magnesium ◦ Co-factors of enzymes ◦ Electrolytes ◦ Structure of tissues such as: bones, teeth, nails, blood, nerves cells and muscles ESSENTIAL NUTRIENTS  Macronutrients ◦ Body cannot synthesize; MUST get from food ◦ Proteins provide essential amino acids ◦ Fats contain essential fatty acids ESSENTIAL NUTRIENTS CONT’D ESSENTIAL NUTRIENTS CONT’D  Essential amino acids ◦ Animals cannot synthesize some amino acids, or not in the amount that is needed for body requirements ◦ Need to be provided through diet in monogastric animals  Pigs and dogs need a total of 10  Chickens and cats need a total of 11 ESSENTIAL NUTRIENTS CONT’D 1. Arginine (Arg) 2. Histidine (His) 3. Lysine (Lys) 4. Isoleucine (Ile) 5. Leucine (Leu) 6. Methionine (Met) 7. Phenylalanine (Phe) 8. Threonine (Thr) 9. Tryptophan (Try) 10. Valine (Val)  In addition to these 10 essential amino acids ◦ Cats need taurine (Tau) ◦ Chickens need glycine (Gly) Essential Function A.A. Arg Important role in cell division, wound healing, removing ammonia from the body, immune function and the release of hormones. His Aids in making the neurotransmitter, histamine (role in immune function, digestion, sleep and sexual function) Lys Involved in the production of hormones and energy Important for calcium and immune function Ileu Involved in muscle metabolism and immune function Helps to make hemoglobin and regulate energy Leu Helps to make protein and growth hormones Helps grow and repair muscle tissue, heal wounds and regulate blood sugar levels Met Helps with tissue growth, metabolism, detoxification, feathering Helps with the absorption of some minerals e.g. zinc and selenium Phe Helps to make neurotransmitters, including epinephrine, norepinephrine and dopamine Important for the production of other amino acids Thr Helps to make proteins and is important for healthy skin and teeth Important role in collagen and elastin Try Helps to maintain correct nitrogen balance, make a neurotransmitter called serotonin (regulates mood, appetite and sleep) Val Involved in muscle growth, tissue regeneration and making energy Tau Critical for normal vision, digestion, heart muscle function, to maintain normal pregnancy and fetal development and to maintain a healthy immune system Gly Important for collagen, the main structural protein of connective tissue, such as bone, skin, ligaments, tendons and cartilage ESSENTIAL NUTRIENTS CONT’D  Essential fatty acids ◦ Linoleic acid (omega-6 fatty acid)  Vegetable oils, corn oil, safflower oil ◦ Alpha-linolenic acid (omega-3 fatty acid)  Green leafy vegetables, flax and chia seeds and canola, walnut and soybean oils ◦ Eicosapentaenoic acid (omega-3 fatty acid)  Cold water ocean fish and fish oils, krill oil, algae products ESSENTIAL NUTRIENTS CONT’D ◦ Docosahexaenoic acid (omega-3 fatty acid)  Cold water ocean fish and fish oils, krill oil, algae products ◦ Arachidonic acid  Not found in plants  Animal fats and tissues  Can be synthesized from linoleic acid in most mammals except in cats (essential nutrient in a cat’s diet, along with EPA and DHA) ESSENTIAL NUTRIENTS CONT’D  Functions of essential fatty acids: ◦ A component of the phospholipids in cell membranes ◦ Precursor for prostaglandins (arachidonic acid) ◦ Important metabolic regulator  Contraction of smooth muscle  Aggregation of platelets  Inflammation ESSENTIAL NUTRIENTS CONT’D  Deficiency of essential fatty acids: ◦ Growth retardation ◦ Problems with reproduction ◦ Skin lesions; poor skin and hair/fur coat ◦ Kidney and liver disorders THE END