Animal Nutrition and Enzymes PDF

BIOLOGY ANIMAL NUTRITION  ANIMAL NUTRITION Nutrition is the process that deals with the digestion of food and how the body uses it to obtain energy. Food substances are used in the body of an organism to sustain growth, repair worn-out tissues and to furnish energy. IMPORT...

BIOLOGY ANIMAL NUTRITION  ANIMAL NUTRITION Nutrition is the process that deals with the digestion of food and how the body uses it to obtain energy. Food substances are used in the body of an organism to sustain growth, repair worn-out tissues and to furnish energy. IMPORTANCE OF FOOD 1. They provide materials for building, repairing or maintaining normal and healthy body. 2. They help in regulating the body’s metabolic processes. 3. They serve as fuel to provide energy.  ANIMAL NUTRITION CLASSIFICATION OF FOOD Depending on the nature of food and the type of nutrients they contain, food substances can be mainly classified into seven classes: 1. Carbohydrates 2. Fats and oils (Lipids) 3. Proteins 4. Mineral salts 5. Vitamins 6. Water 7. Roughages  ANIMAL NUTRITION Carbohydrates, fats and oils, proteins and water are called primary food substances because they are required by animals in large amounts. Vitamins and mineral salts are called welfare food substances because they are required in small amounts for the growth and development of organisms.  ANIMAL NUTRITION Carbohydrates Carbohydrates are chemical compounds of carbon, hydrogen and oxygen in which hydrogen and oxygen are always present in the ratio 2:1. They have the general formula of Cx(H2O)y. Sources: Rice, Maize, Yam, Millet, Guinea Corn, Potato, Garri and Bread.  ANIMAL NUTRITION Types of Carbohydrates 1. Monosaccharides: These are simple sugars which are directly absorbed by the body cells. They have the general formula of C6H12O6 with only one unit of simple sugar. They are of three types a. Glucose (most simple sugar) b. Fructose (Common in plants) c. Galactose (Found in milk) Some forms of sugar associated with animals are the pentose sugars which include ribose and deoxyribose sugars. These sugars are linked with the formation of nucleic acids.  ANIMAL NUTRITION 2. Disaccharides: These are reducing sugars which contain two units of simple sugars. They have the general formula of C12H22O11. They are of three types a. Sucrose (Glucose + Fructose) b. Maltose (Glucose + Glucose) c. Lactose (Glucose + Galactose)  ANIMAL NUTRITION 3. Polysaccharides: These are complex sugars which consists of more than two units of simple sugars. They have the general formula of (C6H10O5)n. where n represents a large number of molecules. Starch and cellulose are the examples of polysaccharides commonly found in plants. In animals, the only substance similar to starch is the glycogen which is also known as animal starch.  ANIMAL NUTRITION Starch is an insoluble carbohydrate found in corn, wheat, potatoes, beans and peas. Starch gets digested easily; it is first broken into simple sugars that can be absorbed by the body cells by dissolving into the bloodstream. Cellulose is a polysaccharide that makes the cell walls of plants. It provides roughage for proper functioning of the digestive system.  ANIMAL NUTRITION Importance of Carbohydrates 1. Carbohydrate provides energy for proper functioning of the body. 2. It oxides to release heat which is used for maintaining the body temperature. 3. Carbohydrate is used to build exoskeleton of arthropods. 4. Mucus, which acts as lubricant in various metabolic activities of our body, is composed of carbohydrates.  ANIMAL NUTRITION Fats and Oils (Lipids) Fats are the solid lipids at room temperature and known as saturated fats. Oils are the liquid lipids at room temperature and known as unsaturated fats. Both fats and oils are hydrolyzed during digestion to fatty acids and glycerol. Fats and oils are composed of carbon, hydrogen and little oxygen. Sources: Palm oil, Groundnut, Soybean oil, Melon oil, Butter, Fish, Cheese and Lard.  ANIMAL NUTRITION Importance of Fats and Oils 1. Fats and oils produce more energy than the carbohydrates. 2. They provide essential fatty acids to animals. 3. They help in maintaining the body temperature. 4. Fats and oils provide fat soluble vitamins. 5. Fats serve as stored food. 6. Fat under the skin protects the body against a rapid loss of heat.  ANIMAL NUTRITION NOTE Although fats and oils supply more than twice the amount of energy than carbohydrates, it is more difficult for the body to use them completely. Excess storage of fats in the cells and tissues of the body can cause obesity.  ANIMAL NUTRITION Proteins Proteins are complex macromolecules that are made up of smaller units of amino acids. Protein is composed of carbon, hydrogen, oxygen, nitrogen and sometimes phosphorus and sulphur. Sources: Animal - Milk, Egg, Fish, Cheese, Meat and Chicken. Plant - Groundnut, Soyabean and Cowpea.  ANIMAL NUTRITION Importance of Proteins 1. Proteins help in synthesis of ribonucleic acid and deoxyribonucleic acid. 2. They are also used in the synthesis of new protoplasm and cells - they are needed for growth and replacement of dead cells in living organisms. 3. Proteins aid in reproduction. 4. They are also used in the production of hormones.  ANIMAL NUTRITION Mineral Salts Various metabolic activities require different mineral salts for their proper functioning. Most of the minerals can be taken through the food that we eat. Only sodium chloride and iron can be taken directly. Classes of minerals include calcium, phosphorus, magnesium, sulphur, sodium, chlorine, iron, iodine, manganese, fluorine, copper and cobalt.  ANIMAL NUTRITION MINERALS SOURCES FUNCTIONS DEFICIENCY SYMPTOMS  ANIMAL NUTRITION Vitamins Vitamins are organic compounds needed in small quantities to support life. They do not supply energy. However, they do help the body to release energy in carbohydrates, fats and proteins. They also act as chemical enzymes in our body and play an important role in many chemical reactions throughout the body. There are two basic groups of vitamins a. Fat soluble vitamins b. Water soluble vitamins  ANIMAL NUTRITION The fat soluble vitamins include Vitamin A, D, E and K while the water soluble vitamins include vitamin C and Vitamin B- complex. The B-complex vitamins are a. Folic acid b. Thiamine (B1) c. Riboflavin (B2) d. Niacin (B3) e. Pantothenic acid (B5) f. Pyridoxine (B6) g. Cyanocobalamine (B12)  ANIMAL NUTRITION vitamins SOURCES FUNCTIONS DEFICIENCY SYMPTOMS  ANIMAL NUTRITION Water Water is a universal solvent that dissolves many substances. Composition Water is composed of two elements - Hydrogen and oxygen in the ratio of 2:1. Sources: Sources of water available to animals include metabolic water which is obtained from food that the animal eats. Physically, water is obtained from rivers, wells, ponds, taps etc. Rain is the natural source of water.  ANIMAL NUTRITION Importance of water 1. Water constitutes the major part of our body. 2. It is required for metabolic activities in the body. 3. It helps in maintaining the temperature of our body. 4. It acts as solvent for soluble food substances and aids in the process of digestion. 5. It constitutes the major part of the blood and provides medium for transportation of nutrients within the body along with the blood. 6. it also aids in excretion of metabolic wastes (such as urine) from the body. 7. It forms the basis of endocrinal secretions (hormones) in the body.  ANIMAL NUTRITION Roughage Roughage also known as dietary fibre is a general term used to identify a carbohydrate contained in many different types of food. It consists of indigestible fibrous materials derived from vegetables, fruits, carbohydrates and proteins. The main function of roughage is to add bulk to the daily diet, which in turn aids in the digestion process and healthy functioning of the bowel system. Roughage is easily digested by the microorganism of the intestinal tract.  ANIMAL NUTRITION Benefits of roughage in the diet of human beings include the following: 1. It stimulates peristaltic movement in the intestinal tract 2. It reduces the blood cholesterol 3. It reduces the chance of bowel cancer or gall bladder stones 4. It helps in reducing the excess weight gain 5. It helps in lowering blood sugar level 6. It helps in slow release of glucose in the blood 7. It helps in preventing constipation  ANIMAL NUTRITION BALANCE DIET A balanced diet is a diet that provides all the essential nutrients in a proper proportion required by the body for proper growth and good health. A person’s dietary needs vary according to age, weight, sex, physical conditions, metabolism and climate.  ANIMAL NUTRITION In terms of the percentage composition of the food substances, balanced diet should contain: 60% of carbohydrates 10% of fats and oils 15% of proteins 10% of vitamins, mineral salts and water Roughages are equally important as they help in proper digestion of food.  ANIMAL NUTRITION Importance of Balanced Diet 1. A balanced diet encourages proper growth and development of the body. 2. It provides us energy to perform various metabolic processes. 3. It keeps us resistant to diseases. Lack of any nutrients in the balanced diet leads to malnutrition. For example, deficiency of proteins in diet causes a deficiency disease called Kwashiorkor. This disease is common in tropics because of high cost of protein foods.  ANIMAL NUTRITION A child with protein-deficiency disease will have the following features: 1. Changes in skin pigments 2. Decreased muscle mass 3. Loss of body weight 4. Hair changes 5. Irritation 6. Diarrhoea 7. Severe infections 8. Large belly  ANIMAL NUTRITION ENZYMES Enzymes are biological catalysts that accelerate the metabolic reactions without changing their composition in the process. They are proteinous in nature. Characteristics of enzymes 1. They are specific in action 2. They are protienous in nature and are easily denatured at high temperature. 3. They function at specific pH (either acidic or alkaline) 4. They are reversible in action in which both reactions can proceed in both directions under the same or different conditions. 5. Their action is retarded in the presence of inhibitors. 6. They are soluble in water.  ANIMAL NUTRITION Types of Enzymes There are two major types of enzymes: 1. Intracellular enzymes - Enzymes that function inside the cells. Example - enzymes that catalyze the cell respiration inside the mitochondria 2. Extracellular enzymes - Enzymes that carry out their functions outside the cells. Example - Digestive enzymes  ANIMAL NUTRITION Classification of Enzymes Based on the type of food they act upon, enzymes are classified as follows: 1. Amylases: These are the enzymes that act upon starch (complex sugar) and break them down to simple sugars. 2. Lipases: These are the enzymes that act upon fats and oils and break them down into glycerol and fatty acids. 3. Proteases: These are the enzymes that act upon proteins and break them down into simple amino acids.  ANIMAL NUTRITION Digestive Enzymes Digestive enzymes are enzymes that work on food substances by digesting them into simpler substances that can be absorbed by the cells. The digestive enzymes accelerate the rate at which insoluble compounds of food are broken down into soluble forms.  ANIMAL NUTRITION Enzyme Site of Food Action name Secretion substrate Ptyalin/ salivary gland carbohydrat converts Amylase cooked starch es to maltose Pepsin Stomach wall proteins converts protein to polypeptide Renin Stomach wall proteins coagulates milk Trypsin Pancreas proteins converts protein to amino acids Lipase Pancreas Lipids converts fats