Chapter 22Animal 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

NutrientsDefinition 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 H20 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