Chapter 22 Animal Nutrition MSU Anatomy and Physiology

Nutritional Needs of Animals  Animal Nutrition: the science of dealing with how animals use food in the body and how all body processes transform food into body tissues and activities  Nutritional Needs are dependent upon metabolic state (age, activity, gender)  Process animals need to grow, live, reproduce, and work  Each species has its own requirements for a balanced diet  Producers want animals to grow quickly

Nutritional Needs of Animals  Essential Nutrient: compound needed for normal growth and /or survival that cannot be synthesized in the body  Requirements vary with: age, stage of development, environment, activity, and genetics

Nutritional Needs of Animals  Ration : total amount of food an animal has in a 24 hour period  May be fed at specific times or as one meal  Balanced Ration: contains all nutrients required by the animal in correct amounts  That portion of the nutrient which may be broken down (digested), absorbed, and used by the body

Metabolism  What is metabolism? How the body uses food  Anabolic- constructive process  Catabolic- destructive process  Affected by hormones- endocrine system  Blood glucose regulations

Anabolism (p. 378)  Breakdown of carbohydrates produce glucose  Stimulates need for insulin from pancreas  Insulin stimulates skeletal muscles to take glucose or glycogen for energy  Amino acids are absorbed for protein synthesis (stimulated by insulin)

Catabolism  After meal is digested and absorbed, blood glucose concentration decreases  Drop in glucose, endocrine secretions produce drop in insulin secretion and rise in release of glucagon

Species Comparison  Ruminants have lower blood glucose levels than other herbivores  They must have continuous glucose being produced in the liver

Nutrients Definition of a Nutrient : Component of food that are necessary to sustain life and normal growth  **** Six essential nutrients that animals require are: water, carbohydrates, fats, proteins, minerals, vitamins

Water  Most essential nutrient  2/3 of an animal’s body is water  Helps body to maintain constant temperature  Flushes the animal’s body of waste and toxic materials  A loss of 20% of body water will result in death  Animals generally need about three pounds of water for every pound of solid food they consume

Carbohydrates  Main source of energy  Include sugars, starches, and cellulose  Almost all come from plants  Generally found in grain, wheat, oats, and barley  Largest part of an animal’s food supply  75% of the diet  Not stored in the body and must be provided daily  Converted to fats

Carbohydrates 1. Sugars: fruits and milk  Simple- called monosaccharides  Glucose and fructose  Double- called disaccharides  Sucrose-table sugar 2. Starches: grains and plants  Converted to glucose during digestion  Cereals, oats, and corn 3. Fiber: plant cells  Material left after food is digested  Aids in digestion and bacteria in the intestinal tract  Hay and grass

Fats  Lipids- term for fats and oils  Fats are solid  Oils are liquids  Energy source  Insulates animals in cold weather  Increases palatability of taste of food  Source of fatty acids

Proteins  Structure and function of cells  Form chains of amino acids  Deficiency leads to poor growth and body weight, poor immune system, and poor health  Increased protein can lead to kidney problems  Essential amino acids  Supplied in diet  Dogs need 10  Cats need 11- additional need for taurine  Nonessential amino acids  Synthesized by diet

Proteins  Biologic value- describes quality of the source  High values are more easily digested  Expressed in %  Common sources of protein:  eggs  fish and soybean meal  milk  beef  corn

Minerals  Macrominerals- minerals needed in large amounts  Calcium: bone and teeth formation  Phosphorus: aids in use of protein  Iron: strength and hemoglobin for RBC’s

Minerals  Microminerals- trace minerals needed in smaller amounts  Iodine: strength and vital signs production  Magnesium: muscles  Sodium: water balance  Potassium: transfer nutrients

Vitamins  Function: they act as coenzymes for biochemical reactions  Fat soluble:  Stored in fat and liver and released when needed  Vitamins A, D, E, K  Vitamin A most common vitamin NOT available in commercial foods  Water soluble:  Dissolved by H 2 0 and needed daily  Vitamins B complex, biotin, C, folic acid and niacin Vitamins are supplied to the body through the use of supplements  Additives placed into the diet in solid or liquid form when needed by the animal

Animal Nutrition and Concentrations  Concentration of food is dependent on how it is delivered to the animals  based on dry matter, the amount of nutrients without the water  determined by the amount of food fed divided by the percentages of dry matter * Digestion – break down of food from large molecules to smaller molecules

Diet Formulation

Types of Diets  Different species, ages of animals, activity of animals, and health status of an animals all must be considered  Factors to consider: age, environment, species, size, health condition, breed, and medical history

Growth Diets  Young animals may be placed on it  Specialized and formulated to increase the size of muscles, bones, organs, and weight  Include nutrients such as protein, vitamins, and minerals  Each animal species will have specific needs and requirements

Maintenance Diets  Given to adult animals that are in their prime age and in a healthy condition  Require energy to work and be active, energy to maintain the body’s temperature, and energy for good health  Consist of high fat and carbohydrates and small amounts of proteins, vitamins, and minerals

Reproductive Diets  Given to breeding animals for additional nutrient needs  First trimester of a pregnancy in animals is the most critical time for nutrition  Male breeding animals require a diet in order to produce sperm

Lactation Diets  Provided to females that have completed the gestation phase and are producing milk in order to nurse young  Require large amounts of water, high amounts of protein, vitamins, and minerals  calcium and phosphorus

Work Diets  For livestock that need and use a large amount of energy for some types of work  Plow animals, draft animals, race horses, hunting animals, plus show and competition animals  Need increased carbohydrates, fats, vitamins, and minerals

Reduced Calorie Diets  Often for animals that are overweight or less active due to health complications  Specific for low energy needs of animals and are formulated with decreased amounts of carbohydrates, fats, and proteins  Moderate vitamins and minerals

Senior Diets  Specific to age and health  Usually low in carbohydrates and fats; moderate in protein  Formulated for animal types based on digestive systems

Feed Types

Feeding Animals  Feed is what animals eat in order to obtain nutrients and nutrition  Feedstuff is the ingredients in animal food that help determine the nutrient contents  Divided into classes based on the most numerous type of nutrient

Forages  Roughages – high in fiber and are plant-based sources  Most are low in protein with the exception of alfalfa hay  Hay and grass forage sources tend to be relatively inexpensive; are dependent on the weather

Concentrates  Food sources that are provided to an animal as an additional nutrient source when the primary food source is not adequate or abundant  High in protein and energy

Supplements  They are provided when necessary as a diet additive during specific health or conditional requirements  May be a vitamin, a mineral, or a mineral block such as salt

Body Condition Scoring  Weight is measured by an ideal body appearance  Rating of how an animal outwardly appears is based on an ideal weight  On a 1-10 scale, 5 is average and considered ideal weight, 7 and 10 are overweight, 4 and below are underweight

Food Analysis  Process of determining the nutrients in food and prepared mixes to assure it serves as a balanced ration  Legally required to be placed on food label  Nutritional information is prepared by the National Research Council (NRC)  Required on label: product name, nutrient list, bar code, and manufacturer’s name and address

Feeding Schedules  Feeding animals may be done by free choice or by scheduled feedings  Free choice allows animals to eat whenever they want food  Scheduled feedings are more common for companion animals or livestock that are housed separately or are in reduced numbers