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PEARSON SQUARE Balancing a Ration

Unit 5: Feeds, Nutrition and Digestion

Lesson 13: Balancing a Feed Ration

Daily Food for Thought How do we

decide what goes into a healthy meal?

Animal nutrition as important as human nutrition

Focus on: Feed efficiency Rate of gain Days to market weight Days to Reproducing Days to Milking

Animal Nutrition

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Pearson Square

Useful tool for simplifying and balancing of rations

It shows the proportions or percentages of two feeds to be mixed together to give a percentage of the needed nutrient

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Pearson Square

2000# of feed is needed to feed a 100# growing hog.

A feeding standards table shows that an 18% crude protein ration is needed.

Corn and Soybean Meal (SBM) are selected as feeds.

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Pearson Square

A feed composition table shows

Corn has 8.9% crude protein

SBM has 44.4% crude protein

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Pearson Square

How much corn and soybean meal need to be mixed together for 2000# of feed?

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Pearson Square

Step 1 -Draw a 1- to 2-inch square. Place diagonal lines across the square.

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Pearson Square Step 2 – Write

the percentage of crude protein needed by the animal in the center of the square where the diagonal lines cross

18.0

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Pearson Square Step 3 –Write the

feeds to be used at each corner. Place the percent of crude protein in the feeds after the name of the feed

Corn 8.9%

SBM 44.4%

18.0

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Pearson Square Step 4 – Subtract

the smaller of the numbers from the larger numbers. (This involves crude protein needed by the animal and that provided by the feed.) Write the difference in the opposite corners

Corn 26.4 parts

8.9 % corn

SBM 9.1 parts 44.4% SBM

18.0

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Pearson Square

Step 5 – The numbers at the two right corners are parts of the two feed ingredients that are needed.

26.4 parts corn +9.1 parts soybean meal (SBM) 35.5 total parts

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Pearson Square

Corn 26.4 parts corn 8.9% 35.5 total parts

SBM 9.1 parts SBM 44.4% 35.5 total parts

18.0

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Pearson Square Step 6 – The percentage of each feed

needed in the ration can be found by dividing the number of parts by the total parts, then multiply by 100.

26.4/ 35.5 = .744 x 100 = 74.4% corn 9.1/ 35.5 = .256 x 100 = 25.6% sbm

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Pearson Square Corn 26.4 parts corn 8.9% 35.5 total parts 74.4%

SBM 9.1 parts SBM 44.4% 35.5 total parts

25.6%

18.0

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Pearson Square

Step 7 – The amount of each feed ingredient for a large batch of feed is determined by multiplying the percentage of each by the total amount of feed desired

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Pearson Square

Our batch of feed = 2000 # ( 1 ton)

2000# x .744 = 1488 # Corn 2000# x .256 = 512 # SBM

2000# of feed @ 18% Crude Protein

Problems

You have to formulate a feed for lactating does. They need 15% protein. How much corn and how much soybean meal is needed for 1,000 lbs.?

You need to formulate a feed for feeder pigs. They need 21% protein. How much corn and how much soybean meal is needed for 1,000 lbs.?

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