Chapter 6 – Nutrition and Digestive Systems

Objectives1) Define the terms nutrition and nutrient

2) List the six basic nutrient groups

3) Ruminant and non-ruminant digestive system differences

4) Importance of various nutrients in diets of animals

5) Learn how to use the Pearson Square

• Nutrition – animal receiving a proper and balanced food and water ration so that it can grow, maintain it’s body, reproduce, and supply or produce the things we expect from it. (work, food – eggs, meat, milk, etc., offspring for sale, fur, companionship)

• Nutrient – a single food or group of foods of the same general chemical composition that supports animal life. (Six basic nutrients – water, proteins, carbohydrates, fats, vitamins, and minerals)

1) Water – more important than any other nutrient group

• A) Supports respiration, digestion, & assimilation• B) Transports other nutrients• C) Helps maintain body temperature• D) Helps give the body it’s form – water makes

up 55 to 65% of the animal’s body• E) Carries waste from the body• Keep a supply of good clean, fresh water

available.• Good carrier of drugs for disease control

2) Proteins – complex nutrients composed of carbon, hydrogen,

oxygen, and nitrogen.

• A) Develop & repair organs and tissues

• B) Produce milk, wool, and eggs

• C) Develop the fetus

• D) Generate enzymes & hormones

• E) Develop antibodies

• F) Transmit DNA

2) Proteins - continued• Proteins found in feed materials are broken down

into amino acids during the digestive process• Twenty-five amino acids found in animal feeds• Of these, ten or eleven are Essential Amino Acids

(can’t be produced by the animal’s body and must be supplied in the feed ration)

• Arginine, isoleucine, histidine, leucine, nethioine, threonine, phenylalanine, lysine, trypophan, & valine

• Poultry require glycine. Cystine can be used to replace insufficient amounts of methionine and thus is considered by some to be an essential amino acid.

2) Proteins - continued• Nonessential amino acids are those that aren’t

needed or the animal’s body can produce, so don’t need to be supplied in the feed ration.

• Ruminant animals are capable of manufacturing all the amino acids they require if any one or more amino acids are given in large enough quantities.

• Types of proteins include: Plant - cottonseed meal, alfalfa hay, linseed meal, & soybean meal and Animal – dried milk products, tankage, fish meal, & meat scraps

3) Carbohydrates – converted into energy – carbon, hydrogen, oxygen

• A) Supports breathing, digestion, & exercise• B) Produces heat to keep the body warm• C) Stores fat• Made of groups of chemicals called sugars,

starches, and crude fiber.• Nitrogen-free extract – more easily and

completely digested sugars and starches• Crude fiber – non-digestible bulk or roughage

which ruminants can handle larger amounts

4) Fats – contain same chemical elements at carbohydrates but in

different combinations

• 1) Provides energy• 2) Aids in the absorption of fat-soluble vitamins• 3) Provides fatty acids that are essential in the

diet of animals (linoleic, linolenic, and arachidonic acids)

• Contains 2.25 times as much energy as an equivalent amount of carbohydrates and proteins. Most animals require less that 3% fat.

5) Vitamins – organic substances required in very small amounts to

support specific biochemical reactions• A) Regulate digestion, absorption, & metabolism• B) Develop normal vision, bone, hair, or feathers• C) Regulates body glands• D) Forms new cells• E) Protects animals against diseases• F) Develops & maintains the nervous systems• Fat soluble – stored and accumulated in liver• Water soluble – only limited quantities stored

5) Vitamins - continued

Fat solubleA) A – prevent poor vision, respirator ailments,

digestive problems, & reproductive difficulties.

B) D – Associated with the use of calcium and phosphorus in the body.

C) E – helps develop muscle and important for successful reproduction

D) K – normal blood coagulation

5) Vitamins - Continued

Water-Soluble – C and B-complex vitaminsA) C

B) B1 or Thiamine

C) B2 or Riboflavin

D) Niacin

E) Pantothenic acid or panacid deficiency

F) Vitamin B12 or Cobalamin

5) Vitamins - continued

Water-Soluble – C & B Complex VitaminsG) Choline

H) Folic acid or Folacin

I) Biotin

J) Inositol

K) Para-amino benzoic acid

L) B6 or Pyridoxine

6) Minerals – supplies the materials for building the skeleton & producing enzymes

and hormones

• Twenty elements of animal nutrition• Four considered non-mineral elements (carbon,

hydrogen, oxygen, & nitrogen)• Seven major (Macro-minerals) 1. Calcium (required

more than others in vertebrates) 2. Phosphorus 3. Potassium 4. Sodium 5. Sulfur 6. Chlorine 7. Magnesium

• (Micro-minerals) Iron, Iodine, Copper, Cobalt, Zinc, Fluorine, Manganese, Molybdenum, Selenium

Animal Digestion – process of breaking down food material into various nutrient

forms that can be absorbed in bloodstream

• Ruminant animals (forage-consuming or multi-stomached animals) include cattle, sheep, goats, elk, deer, giraffes, buffalo, camel, and antelope.

• Non-ruminant animals (single stomached or mono-gastric animals) include all of the small animals in the textbook (birds, rabbits, and horses have a single stomach)

Ruminant Animals – four compartments to the stomach

• 1) Rumen – largest compartment that contains bacteria & microorganisms that help to break down the food

• 2) Reticulum – helps in formation of the cud (regurgitated food material) and is known as the hardware stomach for holding foreign materials

• 3) Omasum – removes large amounts of water from the food

• 4) Abomasum – true stomach• Saliva added during chewing aids in process

Non-ruminant Animals – single stomachs

• Food passes from mouth to the stomach through the esophagus.

• Stomach breaks down proteins and breaks down fat into fatty acids and glycerol

• Foods passes into small intestines for primary digestion and absorption of carbohydrates, fats, & proteins

• Undigested food passes into large intestine for addition of water and aid in easier passage from the body

Horses

• Consume large amounts of forages

• Small single stomachs with a large cecum and colon located between the small and large intestines. The cecum has bacteria that allows the horse to digest roughage materials.

• No gallbladder so the bile is secreted directly from the liver.

Rabbits

• Like horses in that it has a large cecum to be able to digest roughage

• Consumption of the feces allows for full use of the bacterial action in the digestive system

Birds• No chewing of food but saliva added for

aid in swallowing

• Food passes down the esophagus (gullet) into the enlargement of the esophagus (the crop) which is where food is stored and softened.

• Food then passes to the ventriculus (gizzard) which is the largest organ where the food is ground and crushed

• Small intestine for absorption of materials

Pearson Square

• Formulation procedure to design simple rations

• Greatest value when only two ingredients are to be mixed

• Most important number is the middle number as it represents the nutritional requirement of an animal for a specific nutrient.

Why Balance Rations?

• Maintain animal health

• Optimum animal production

• Reasonable production costs for the farm manager

Math terms involved• Diagonal – a square with lines connecting

opposite corners

• Percent – 1% of a number means 1 hundredth of a number

• Pound – weight of an object – Lb., #

• Systems of Equations – Two or more equations in two or more variables to be solved simultaneously

• Ratio – the comparison of two numbers by division

Sample Problem

• 2,000 pounds of feed is needed to feed 100 pound growing hogs. A feeding standards table shows that a 14 percent crude protein ration is needed. Corn and soybean oil meal are selected as feeds. A feed composition table shows that corn has 8.9 percent and soybean oil meal has 45.8 percent crude protein on an as-fed basis. How much corn and soybean oil meal need to be mixed together for 2,000 pounds of meal?

Sample Problem

• What’s important?

• 2,000 pounds of feed needed

• 14 percent crude protein needed

• Corn contains 8.9 percent protein

• Soybean oil meal contains 45.8 protein

Pearson’s Square

• Step 1

• Draw a square with lines connecting the opposite corners. Write the percent of crude protein needed (14) in the center of square where lines cross.

14%

Pearson’s Square• Step 2• Write the feeds to be used and their crude

protein percents at the left hand corners of the square.

Corn 8.9%

Soybean 45.8%

14%

Pearson’s Square

• Step 1

• Draw a square with lines connecting the opposite corners. Write the percent of crude protein needed (14) in the center of square where lines cross.

•

• Step 3

• Subtract the smaller number from the larger, along the diagonal lines. Write the difference at the opposite end of the diagonals.

Corn 8.9% 31.8%

Soybean 45.8% 5.1%

14%

Pearson’s Square

• Step 3 – Check

• The sum of the numbers on the right equals the difference in the numbers on the left.

Corn 8.9% 31.8%

Soybean 45.8% 5.1%

36.9% 36.9%

14%

Pearson’s Square

• Step 4• Divide the parts of each feed by the total parts to

find the percent of each feed in the ration.

• Corn 31.8 / 36.9 x 100 = 86.2%

• Soybean oil meal 5.1 / 36.9 x 100 = 13.8%

Pearson’s Square

• Step 5a• It is known that 2,000 pounds of the mixture is

needed. Thus, the amount of corn needed is 1,724 pounds. This is found by multiplying the total pounds of the mix by the percent of corn in the mix.

• 2,000 x 0.862 = 1,724 pounds of corn

Pearson’s Square

• Step 5b• The amount of soybean oil meal needed is 276

pounds. This is found by multiplying the total pounds of the mix by the percent of soybean oil meal in the mix.

• 2,000 x 0.138 = 276 pounds of soybean oil meal

Pearson’s Square

• Step 6• Check the mix to make sure the protein need is

met. Multiply the pounds of corn by the percent of protein in the corn (1,724 x .089 = 153). Multiply the pounds of soybean oil meal (276 x .458 = 126). Add the pounds of protein together (153 + 126 + 279). Divide the total pounds of protein by the total weight of the mix and multiply by 100 to get the percent of protein in the mix (279 / 2,000 X 100 = 14%).

Pearson’s Square

• Algebraic Solution – Complete the table:

% Pound Protein Mix

Corn 8.9 X .089

Soybean oil meal

45.8 Y .458

Total 14 2,000 .14(2,000)

Algebraic SolutionX + Y = 2,000

.089 X + .458 Y = .14 (2,000)

Solve for a variable, in this case X:

X + Y = 2,000

- Y - Y

_____________

X = 2,000 - Y

Algebraic Solution

• Substitution – Solve for Y• For X, substitute (2,000 – Y)

1) .089 (2,000 – Y) + .458 Y = .14 X 2,000

2) 178 - .089Y + .458Y = 280

3) 178 + .369Y = 280

Algebraic Solution

• Continue substitution – Solve for Y

3) 178 + .369Y = 280

4) - 178 - 178

0 + .369Y = 102

5) .369Y / .369 = 102 / .369

Y = 276.4 pounds soybean oil meal

Algebraic Solution

• Solve for X – substitute the value of Y into the first equation

X + 276.4 = 2,000

- 276.4 - 276.4

X + 0 = 1723.6

X = 1723.6 Pounds of corn

Algebraic Solution

• Check:

X = 1723.6 pounds of corn

Y = 276.4 pounds of soybean oil meal

Substitute to check:

X + Y = 2,000

1723.6 + 276.4 = 2,000