- oldest and simplest method of balancing rations
- can only be used to determine the proportions of two ingredients
- frequently used for smaller herds and flocks
|Step 1: Create a square like the one above and provide the necessary information.
Step 2: Cross subtract:
Feed A Nutrient Content - Nutrient Requirement of Animal = Parts of Feed B
Feed B Nutrient Content - Nutrient Requirement of Animal = Parts of Feed A
Add the parts together to get total parts of feed.
Step 3: Determine the percentage of diet each component should be by dividing the part of the feed by the total parts:
(Parts Feed A / Total Parts) X 100% = ______% Feed A
(Parts Feed B / Total Parts) X 100% = ______% Feed B
- Used to balance for 1 or 2 nutrients with 2 feedstuffs
X = % Feed A in mix
Y = % Feed B in mix
Equation 1: X + Y = 100 (as in 100% of or diet or 100 lb of feed)
Equation 2: (% nutrient in A)x + (% nutrient in B)y = % nutrient required by animal
Solve the equations for one unknown (x).
Then subtract Equation 1 from Equation 2.
Solve for x.
Use x to solve for y.
- Specific in that they are designed for feeding one species
- Self-contained and simple to use
- User must be able to determine if results are reasonable