Balancing Feed Rations

Pearson’s Square

Maintain animal health

Optimum animal production

Reasonable production cost for the farm manager

Why Balance Rations?

Why maintain animal health in horses?So that the horse can have a balanced diet that

can maintain the horse’s weight and energy supply.

Maintain Animal Health

Helps give protein and nutrient requirements needed for different stages of production.MaintenanceLactationGestationGrowth

YearlingLong-yearling2 year oldMature (4+ years)

Optimum Animal Production

How does balancing a feed ration affect production cost? (better or worse?)

BetterIt keeps from wasting feed

Production Cost for Farm Manager

DiagonalA square with lines connecting the opposite corners

Percent1% of a number means 1 hundredth of a number or .016% means six hundredths or .06

PoundWeight of an objectLb, #

Systems of EquationsTwo or more equation in two or more variables to be

solved simultaneouslyRatio

The comparison of two numbers by division

Math Terms Involved

Nutrient Concentrations

Feed Compositions

2,000 pounds of feed is needed to feed a pregnant mare. A feeding standard table shows that a 10% crude protein ration is needed. Corn and soybean meal are selected as feeds. A feed composition table shows that corn has 9% and soybean meal has 45% crude protein on as-fed basis. How much corn and soybean meal need to be mixed together for 2,000 pounds of feed?

Sample Problem

What’s important?2,000 pounds of feed needed10% crude protein neededCorn contains 9% proteinSoybean meal contains 45% protein

Sample Problem

Step 1Draw a square with lines connecting the

opposite corners. Write the percent of crude protein needed (10) in the center of the square where the lines cross.

Pearson’s Square

Step 2Write the feeds to be used and their crude

protein percents at the left hand corners of the square.

Pearson’s Square

Step 3Subtract the smaller number from the larger

number along the diagonal lines. Write the difference at the opposite end of the diagonals.

Pearson’s Square

Step 3—checkThe sum of the numbers on the right equals the

difference in the numbers on the left.

Pearson’s Square

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

to find the percent of each feed in the ration.

Corn: (35/36) x 100 = 97%

Soybean: (1/36) x 100 = 3%

Pearson’s Square

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

needed. Thus, the amount of corn needed is 1,940 pound. This is found by multiplying the percent of corn in the mix by the total pounds of the mix.

2,000 x 0.97 = 1,940 pounds

Pearson’s Square

Step 5The amount of soybean meal needed 60

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

2,000 x 0.03 = 60 pounds

Pearson’s Square

Step 6Check the mix to make sure the protein needed

is met. Multiply the pounds of corn by the percent of protein in the corn (1,940 x 0.09 = 174.6). Multiply the pounds of soybean meal by the percent of protein in the soybean meal (60 x 0.45 = 27). Add the pounds of the protein together. Divide by the total weight of the mix.

Pearson’s Square

Step 6174.6 + 27 = 201.6

(201.6 / 2000) x 100 = 10%

Pearson’s Square

% Pound Protein

Corn 9 X .09

Soybean 45 Y .45

Total 10 2,000 .10(2,000)

Algebraic Solution

X + Y = 2,000

.09X + .45 Y = .10(2000)

Solve for a variable, in this case X:X + Y = 2,ooo -Y -Y

X = 2,000 - Y

Algebraic Solution

Solve for Y.09(2000 – Y) + .45Y = 200

Substitute X with X=(2,000 – Y)180 - .09Y + .45Y = 200

Algebraic Solution

180 + .36Y = 200 -180 -180

.36Y = 20 (Divide both sides by .36)

Y= 55.6 pounds of soybean

Algebraic Solution

Solve for X Substitute the value of Y into the first equation X + 55.6 = 2,000 -55.6 -55.6

X = 1944.4 pounds of corn

Algebraic Solution

CheckX = 1944.4 pounds of cornY = 55.6 pounds of soybean

Substitute to checkX + Y = 2,0001944.4 + 55.6 = 2,000

Algebraic Solution

2,000 pounds of feed is needed to feed a lactating mare. A feeding standard table shows that a 12.5% crude protein ration is needed. Oats and linseed meal are selected as feeds. A feed composition table shows that oats has 12% and Linseed meal has 38% crude protein on as-fed basis. How much oats and linseed meal need to be mixed together for 2,000 pounds of feed?

Sample Problem

2,000 pounds of feed is needed to feed a weanling. A feeding standard table shows that a 14.5% crude protein ration is needed. Mixed sweet feed and a commercial protein supplement are selected as feeds. How much mixed sweet feed and commercial protein supplement need to be mixed together for 2,000 pounds of feed?

Sample Problems

2,000 pounds of feed is needed to feed a yearling. How much sorghum and soybean meal need to be mixed together for 2,000 pounds of feed?

Sample Problem