1. Balancing Feed Rations
Advanced Animal Science
130.7(c)9D

2. One Minute!
Write down everything you ate yesterday

3. Categorize the items, by the categories listed as well as junk food
Categorize the items, by the categories listed as well as junk food. Which group did you eat the most food from? The least? This image portrays what a balanced diet should look like for people. Just like people animals have their own nutritional needs that must be met in order for the animal to be healthy and productive.

4. Ration
A ration is the total amount of feed consumed in a 24 hour period
A ration should provide the proper proportion of each nutrient specific to the animal’s needs

5. Steps to Developing a Ration
Identify needs of the animal
Identify available feedstuffs
Calculate the amount of each feedstuff to use in the ration
Check the ration against nutrient needs

6. Pearson Square
Method used to balance the nutrient content of two feedstuffs in a ration
Need to know:
Nutrient requirements of animal
Nutrient content of feedstuff

7. Example Problem
Marvin wants to formulate a feed ration that provides 12% Crude Protein (CP) for his sows. On hand he has corn which contains 8.9% CP and soybean meal which contains 44.4% CP. If Marvin wants 700 lbs. of feed, how much corn and soybean meal (SBM) should he use?

8. Step 1: Set up the Pearson Square
Feed #1 Nutrient %
Part of Feed #1 Needed
Nutrient % Requirement of Animal
Feed #2 Nutrient %
Part of Feed #2 Needed

9. Step 2: Fill in the Square
Feed #1 Nutrient %
Parts of Feed #1 Needed
Corn 8.9% CP
_____ parts Corn
12% CP
Nutrient % Requirement of Animal
SBM 44.4% CP
_____ parts SBM
Feed #2 Nutrient %
Parts of Feed #2 Needed

10. Subtract diagonally: 44.4 – 12 = 32.4
Step 3: Subtract
Subtract diagonally: 44.4 – 12 = 32.4
Corn 8.9% CP
_____ parts Corn
32.4
12% CP
SBM 44.4% CP
_____ parts SBM

11. Step 3: Subtract Subtract diagonally: 8.9 – 12 = -3.1
No negatives! Always use absolute value 3.1
Corn 8.9% CP
_____ parts Corn
32.4
12% CP
SBM 44.4% CP
_____ parts SBM
3.1

12. Add parts of each feed: 32.4 + 3.1 = 35.5
Step 4: Add
Add parts of each feed: = 35.5
Corn 8.9% CP
_____ parts Corn
32.4
12% CP
SBM 44.4% CP
_____ parts SBM
3.1
35.5 Total Parts

13. Step 5: Convert Parts to %
Formula: Parts / Whole x 100 = %
Corn: 32.4 parts / 35.5 parts = .913 x 100 = 91.3% Corn
SBM: 3.1 parts / 35.5 parts = .087 x 100 = % SBM
Rounded to 3 places

14. Step 6: Convert % to Lbs.
Now we need to convert the % to lbs. to find out exactly how much of each ingredient will go into the ration.
We need 700 lbs. of feed for Marvin’s sows
Total lbs. of ration x decimal form of feed % = Total lbs. of feedstuff
Corn: 700 lbs. x .913 = lbs. of Corn
SBM: 700 lbs. x .087 = 60.9 lbs. of SBM

15. Step 7: Check Your Work
Add up the feedstuff totals to be sure they equal the total ration amount.
639.1 lbs. of Corn +
60.9 lbs. of SBM =
700 lbs. of feed

16. Step 7: Check Your Work Corn (8.9% CP): 639.1 lbs.
639.1 lbs. x .089 CP = 56.9 lbs. CP
SBM (44.4% CP): 60.9 lbs.
60.9 lbs. x .444 CP = 27.0 lbs. CP
Add for total lbs. CP
56.9 lbs. CP lbs. CP = 83.9 lbs. CP
Divide by total feed for nutrient requirement
(83.9 lbs. CP / 700 lbs.) x 100 = 12% CP for Sows

17. Answer
Marvin needs lbs. of Corn and 60.9 lbs. of SBM to make 700 lbs. of feed for his sows

18. Algebraically
.12 CP x 700 lbs. = 84 lbs. of CP required in Marvin’s sow feed
.089x y = 84 lbs. CP
x + y = 700 lb. feed
X = 639.1, Y = 60.9
X= corn Y= SBM

19. Practice
Angela needs 300 lbs. of rabbit feed containing 12% CP. She wants to formulate a ration containing alfalfa hay at 17.1% CP and clover at 4.4% CP. How much clover and alfalfa hay should Angela use to make her feed?

20. Nutrient % Requirement of Animal
Practice
Feed #1 Nutrient %
Part of Feed #1 Needed
Nutrient % Requirement of Animal
Feed #2 Nutrient %
Part of Feed #2 Needed

21. Nutrient % Requirement of Animal
Practice
Feed #1 Nutrient %
Parts of Feed #1 Needed
Alfalfa 17.1% CP
7.6 parts Alfalfa
12% CP
Nutrient % Requirement of Animal
Clover 4.4% CP
5.1 parts Clover
Feed #2 Nutrient %
Parts of Feed #2 Needed
12.7 Total Parts

22. Practice Alfalfa: 7.6 / 12.7 = .598 x 100 = 59.8% Alfalfa
300 lbs. x .598 = lbs. Alfalfa
Clover: 5.1 / 12.7 = .402 x 100 = 40.2% Clover
300 lbs. x .402 = lbs. Clover
Check your work
179.4 lbs. Alfalfa x .171 CP = lbs. CP
120.6 lbs. Clover x .044 CP = 5.31 lbs. CP
30.68 lbs. CP lbs. CP = lbs. CP
35.99 lbs. CP / 300 lbs. = 12.00% CP

23. Answer
Angela needs lbs. of Alfalfa hay and lbs. Clover to make 300 lbs. of feed for her rabbits.

24. Complete “Pearson Square” Worksheet
Independent Practice
Complete “Pearson Square” Worksheet