ADSC 2010 Lecture 10 Outline of Last Lecture I Meats Proteins 1 Myofibrillar Proteins a Myosin and Actin b Troponin and Tropomyosin 2 Stromal or Connective Tissue Proteins a Collagen b Elastin II Meat Lipids A Muscle Fat III Meats Nutritive IV Meats Acceptability 1 Tenderness 2 Juiciness 3 Flavor Aroma 4 Appearance 5 Price V Meat Value Determinants A Carcass Weight B Carcass Category and Grade a Beef 1 Yield 2 Quality Outline of Current Lecture Meats Nutrients I Nutrients A Six Classes of Nutrients II Water A Functions B Average Daily Consumption III Carbohydrates A Classification of Carbohydrates a Monosaccharaides b Disaccharides c Polysaccharides B Functions of Carbohydrates IV Fats Lipids A Classification B Types of Fatty Acids C Physical Forms D Dietary Requirements a Essential Fatty Acids b Compounds Lipids c Sterols E Functions V Proteins A Amino Acids B Essential Amino Acids C Semi Essential Amino Acids D Non Essential Amino Acids E Dietary Crude Protein F Non Protein Nitrogen NPN Current Lecture I Nutrients The study of feedstuffs and their efficient utilization by livestock in producing animal products such as meat milk wool and work Feed costs are the Largest Production Costs in the livestock industry 6075 Nutrient a feed constituent chemical substance that is absorbed from the digestive tract and its metabolized by the body to support life A Six Classes of Nutrients 1 Water MOST IMPORTANT 2 Carbohydrates 3 Fats Lipids 4 Proteins 5 Vitamins 6 Minerals II Essential Nutrients cannot be synthesized by the body and must be supplied through the diet Comprises 70 75 of body weight Most highly consumed Nutrient 2 1 Animals will die more quickly from lack of H2O than lack of any other nutrient Water A Functions 1 Transportation 2 Media for Metabolic RXNS 3 Thermoregulation 4 Lubrication 5 Gives cells their shape osmotic pressure B Average Daily Consumption III Swine 1 5 3 Gal Day Cattle 10 14 Gal Day Horses 10 14 Gal Day Sheep 1 3 Gal Day Carbohydrates Provide energy A Ways we measure energy content 1 Calories Cal heat required to raise the temperature of 1g of H2O 1 C from 14 15 2 KiloCalories Kcal 1000 calories 3 MegaCalories Mcal 1 million calories Energy content 4 2 Kcal gram B Classification of Carbohydrates a Monosaccharaides Simple sugars 5 6 carbons 1 Glucose Glu 6 Carbons Dextrose 2 Fructose Fru 6 Carbons 3 Galactose Gal 6 Carbons 4 Ribose Deoxyribose 5 Carbons b Disaccharides 1 Sucrose Glu Fru alpha 1 2 Linkage 2 Lactose Glu Gal Beta 1 4 Linkage 3 Maltose Glu Glu alpha 1 4 Linkage c Polysaccharides C5H10O5 1 Starch GLU 1 4 Linkage Used primarily for energy storage in plants Primarily in concentrates Concentrates high energy low fiber feedstuff that is highly digestible Examples corn grain sorghum wheat 2 Glycogen Animal Starch Stored in liver and muscle 3 Cellulose GLU 1 4 Linkages Located in the cell walls of plants Lowly digestible Primarily in roughages Roughages high fiber low energy foodstuff that is lowly digestible Examples Hay pasture silage 4 Hemi Cellulose 1 4 Linkage 5 Lignin INDIGESTIBLE Ruminants can break down Beta Linkages and Starch C Functions of Carbohydrates 1 Energy Source 4 2 Kcal gram 50 75 Dry Matter Carbs 2 Fiber Content Laxative Effect Maintains healthy lining and muscle tone of digestive tract Cellulose heme cellulose and lignin IV Fats Lipids like carbs with lower proportion of elemental oxygen A Classification Simple Lipids Triglycerides Glycerol 3 Fatty Acids Triglycerides 3H2O B Types of Fatty Acids 1 Steric Acids Saturated Linear 2 Oleic Acid Unsaturated Have at least two carbon double bonds C Physical Forms 1 Solids Fats Saturated long chains 2 Liquids Oils Unsaturated Angled chains Dietary lipids can impact the physical characteristics of carcass fat especially in monogastrics Monogastrics have one stomach usual with an acid environment Example PIGS D Dietary Requirements a Essential Fatty Acids 1 Linoleic Acid 18 2 2 Linolenic Acid 18 3 3 Arachidonic Acid 20 4 b Compounds Lipids 1 Glyco Lipids Brain nervous system 2 Lipo Proteins Lipid transportation in body 3 Phospho Lipids Important to cell structure c Sterols 1 Cholesterol involved in membrane structure and a pre cursor for other compounds 2 Steroid Hormones i Testosterone ii Estrogen 3 Vitamin Pre Cursors ergosterol sunlight vitamin D E Functions 1 Storage form of metabolic fuel 9 45 Kcal gram 2 25X CHO X kilocal 2 Transportation of energy 3 Aids in absorption of Vitamins 4 Protection and Insulation of Vital organs 5 Hormone Precursors 6 Juciness and Flavor in Meats Feedstuffs generally contain 1 4 Fats lipids except for oilseeds with contain more than 18 Examples soybeans cottonseed canola V Proteins Building blocks for animal proteins A Amino Acids Basic Unit for Proteins Classes of Amino Acids B Essential Amino Acids MATT HILL VP Methionine Arginine Threonine Tryptophan Histidine Isoleucine Leucine Lysine Valine Phenylalanine C Semi Essential Amino Acids Glycine Tryosine Cysteine D Non Essential Amino Acids Alanine Aspartic acid Glutamine Glutamic acid Serine Asparagine Proline Chains of amino acids linked by peptide bonds Condensation RXN E Functions of Proteins 1 Structure Muscle hair feathers cell wall 70 80 of dry fat free body is protein 2 Regulation and Protection Enzymes Antibodies Hormones Hemoglobin 3 Energy 4 Kcal grams Protein Quality determined by the ability of animals to digest and utilize the protein F Dietary Crude Protein Crude protein of feedstuff is calculated on nitrogen content Protein 16 Nitrogen 100 16 6 25 crude proteins X 6 25 Feedstuff with 4 Nitrogen equates 25 crude proteins 4 N x 6 25 25 crude proteins G Non Protein Nitrogen NPN Example urea uric acids Urea 45 nitrogen 281 25 CP Chicken Litter 35 CP Mammals cannot use this form of Nitrogen microorganisms in the Rumen can Excess urea TOXIC 1 3 of dietary nitrogen from urea 1 of total diet