Introduction to Nutrition PDF

Introduction to Nutrition ANSC 1011 What sustains life as we know it? Carbon Organic compounds Each carbon atom can form bonds with up to four other atoms simultaneously. Well-suited to form long chains of molecules that serve as the basis of life. Water Necessa...

Introduction to Nutrition ANSC 1011 What sustains life as we know it? Carbon Organic compounds Each carbon atom can form bonds with up to four other atoms simultaneously. Well-suited to form long chains of molecules that serve as the basis of life. Water Necessary for many chemical reactions  allows for chemicals to be transported or dissolved. Supports cellular structure and functioning (DNA and proteins). What sustains life as we know it? Energy Either in light or chemical form. Both forms fuel reactions that allow life to grow and reproduce. Conservation of mass: Matter makes up everything visible in the known universe. Matter is never created or destroyed; it cycles through our universe. Same thing happens with energy  law of conservation of energy. Examples? Nutrition The study of how the body uses nutrients to sustain life and for productive purposes. The study of nutrition aims to develop an understanding of: The nutrients that animals consume. The processes involved in nutrient utilization. What is a nutrient? Any chemical substance in the diet that supports or maintains life processes. Animal Nutrition Nutrition affects the general well-being of animals Health Physical and physiological abilities Susceptibility to diseases Ability to recover Animal nutrition in livestock production Objective: to feed livestock effectively. Cost, type of feedstuff, amount, pattern Cost of feed and feeding 45-75% of total cost of operation. Animal Nutrition – Research Broad field Monogastric animals Ruminants 2 additional categories Basic: metabolism Applied/production: animals in production Animal Nutrition Monogastric animals Non-ruminants, one-stomached, simple-stomach Glandular stomach (proventriculus in chicken) Carnivores, omnivores, herbivores Animal Nutrition Ruminants 4-compartment stomach Rumen, reticulum, omasum, abomasum Fiber digestion through fermentation Nutrients and Their Uses Nutrients: substances required for vital processes. Maintenance, growth, reproduction, lactation Dietary essential nutrients: Must be obtained from the diet. Required for normal physiological functions Dietary non-essential nutrients: Not required from the diet. Nutrients Six classes of nutrients Water Carbohydrates Proteins Lipids Vitamins Minerals Main purpose of providing nutrients is to replenish what the animal has used in biological processes. Water Simplest, but most important of all nutrients. Water brings to each living cell the ingredients it requires to function and carries away the end products of its reactions. All life functions depend directly or indirectly on water Nutrient assimilation Digestion Absorption Transport Metabolism Excretion Water Sources of water Drinking Diet: meat, forage, feedstuff Metabolic H2O Functions Transport medium Biochemical reactions Regulation of body temperature Solvent for body solid components Lubricant and cushion for joints Carbohydrates – Basic Composition Elements making up carbohydrates (carbon + hydrates) Carbon, hydrogen, and oxygen Cn(H2O)n Basic unit: saccharide Monosaccharides Glucose, fructose, galactose Disaccharides Sucrose, lactose, maltose Oligosaccharides Polysaccharides Starches, glycogen Carbohydrates Sugars, starches, cellulose found in feedstuff. Primary use is to provide the animal with energy. Starches and cellulose are composed of glucose. Digestion of polysaccharides  glucose Energy production  glycolysis Energy storage  glycogen Easily digested  readily available energy source. Sources of Carbohydrates Plants are the primary source of carbohydrates (photosynthesis). Grass, silage, hay, grains (seeds), fruits Forages are primarily composed of cellulose. Cellulose is an important energy source for multiple herbivores including ruminants and hindgut fermenters. Mammals cannot break down cellulose. Cellulose digestion through microbial fermentation. Sources of Carbohydrates Grains are a major part of livestock feeds Composed of starch and sugars Easily digested Grains: rice, wheat, rye, barley, corn Legumes: beans, peas, lentils Fruits Vegetables: carrots, potatoes, beets Sugar cane and sugar beets Table sugar Carbohydrates from Animal Sources Animal milk sugar Lactose (glucose + galactose) Muscles from animals- glycogen Converted to lactic acid during slaughter. What about honey? Proteins Complex, long chains of amino acids linked by peptide bonds. Primary functions in the body: Components of lean tissue, enzymes, hormones, and body metabolites. Energy Protein requirements depend on age and use of the animal. Growth, maintenance, reproduction, milk production, weight and fat gain, fiber production, laying eggs. Proteins Sources Oil seed meals: soybean, cottonseed Fishmeal, alfalfa meal Distiller grains, corn gluten feed Forage legumes Amino Acids: Other Roles Important roles in biochemical and metabolic processes Growth, reproduction, production 20 standard amino acids 10 essential (9 in humans) Phenylalanine Histidine Valine Isoleucine Tryptophan Lysine Methionine Leucine Threonine Arginine Amino Acids – Other Roles Pigs: Lysine (First limiting) Without adequate amounts, other AAs cannot combine correctly to form muscle protein. Poultry: Methionine Development of digestive tract and growth performance. Increasing muscle mass, feather development, egg production Cats: Taurine (only found in animal-based protein) Normal vision, digestion, heart muscle function, pregnancy and fetal development, immune system. What is a Limiting Amino Acid? Limiting amino acids are found in very low amounts and prevent protein synthesis in the body beyond the level at which they are present. Lipids– Fats Esters of fatty acids and glycerol. Source of energy and source of essential fatty acids Provides 2.25 more energy than carbohydrates on an equal weight basis. Essential fatty acids: Linolenic (ω-6), linoleic (ω-3), arachidonic acid Lipids – Volatile Fatty Acids Main energy source for ruminants Provide ~70% of the total energy requirements Where do VFAs come from? Microbial fermentation Rumen Volatile fatty acids Acetic, propionic, butyric Lipids-Fats Functions Energy supply in the diet Provides essential fatty acids Necessary for transport and absorption of fat-soluble vitamins Insulation, heat protection, energy storage Lipids – Fats Biochemical functions Cell membrane composition Metabolites Cellular signaling Gene expression regulation Energy source Immune cell differentiation Adipose tissue composition Microbiota composition Vitamins Organic compounds needed by the body in very small amounts. Fat-Soluble Water-Soluble Fat-soluble Vitamin A Vitamin C Regulation of body functions Vitamin D Niacin Vision, blood clotting, tissue maintenance Vitamin E Biotin Growth: bone development Vitamin K Thiamine Riboflavin Water-soluble Pantothenic acid Body metabolic regulation Folic acid Minerals Inorganic compounds needed for the correct functioning of the organism. Constituents of bones and teeth. Important part of body’s enzyme systems (cofactors). Macrominerals: Calcium (Ca), Phosphorous (P), Sodium (Na), Chlorine (Cl), Magnesium (Mg), Sulfur (Mg), Sulfur (S), Potassium (K). Microminerals: Iron (Fe), Iodine (I), Zinc (Zn), Copper (Cu), Cobalt (Co), Chromium (Cr), Selenium (Se), Vanadium (V), Manganese (Mn), Fluoride (F). Minerals Additional Roles Sources Body fluid balance Purified minerals Body acid balance Salt Nerve transmission Trace mineralized salt Muscle contraction Oyster shells Oxygen transmission Lime Wound healing Bone meal Immune function Body Functions and Body Requirements Animals need nutrients for maintenance, production, and reproduction. The amount required depends on many things Species (digestive tract) Level of production Type of product (work, fetus, milk, growth, eggs, fiber) Body Functions and Body Requirements Nutrients needs are additive and must be fed in sufficient amount to simultaneously meet all the animal’s current requirements. Maintenance: maintaining the body at a constant weight and temperature. Basal metabolism and normal animal movement. Maintenance needs must be met before the animal will produce any product. Growth: process of increasing body weight (size). Nutrient needs are high because all systems in the body are Body Functions and Body Requirements Finishing: final growth and fattening phase of the production of meat animals. Energy is needed in much higher proportion. Why? Less protein is needed compared to growth and reproduction. Production: output of products eggs, milk, wool. Lactation is the most nutrient demanding production activity. Work: specialized production function (horses, asses, working dogs) Nutrients that provide energy are required in higher proportions. Body Functions and Body Requirements Reproduction: basic biological necessity for species to survive. Nutrient needs increase during the third trimester of pregnancy. Protein Energy Vitamins and minerals Dairy cows? Body Functions and Body Requirements Feed Analysis Proper feeding requires knowledge of nutrient kinds and levels in a feedstuff to balance the nutrients and meet animal’s requirement. Chemical procedures: to analyze feeds for nutrient content. Proximate analysis: DM, CP, CF, NFE, ether extract, ash Biological procedures: use animals to test feed. Palatability, bioavailability, animal performance Does not give information on digestion and absorption of nutrients. Value of Feedstuff to Animals We must combine the chemical analysis with information about how feed affects the animal. Develop feeding standards and recommendations for feeding animals. Feeding trials: determine if the animal will eat the feedstuff and how they perform. Digestion trials: determines the degree to which a feedstuff is digested and absorbed by the animal. Digestion Trials Concepts: Diet vs Ration Diet: mix of feed ingredients fed to an animal. Ration: the amount of feed offered to an animal during a 24-h period. 1 ton of steer feed: Steer eats 92.2% ground corn 5kg/day of this 7% Soybean meal diet 0.1% vitamin a premix 0.7% mineral Concepts: Total Mixed Ration A diet providing all the nutrition requirements a cow needs to be healthy and produce milk. Forages, grains, protein feeds, minerals, vitamins, feed additives “Effective, efficient, and profitable way to feed dairy cows.” Provides more control and accuracy over the amount of feed given than separate ingredients. With every bite, cows eat a nutrient balanced ration. Benefits of Total Mixed Rations Can increase milk production 1 to 2.5 kgs per cow daily. Milk fat and other components can increase. Stabilizes rumen pH and optimizes rumen feed digestion The rumen microorganisms have a uniform supply of protein and carbohydrates throughout the day. This maximizes rumen fermentation and the production of rumen microbial protein.