FORMULATING POULTR FEEDS - SIMPLE CALCULATIONS)
The Pearson Square method relies on the Digestible Crude Protein (DCP) as the basic nutritional requirement for feed.
The most common ingredients used in poultry feed are whole maize, maize germ, cottonseed cake, soya beans, sunflower or omena (fishmeal).
The farmer needs to know the Digestible Crude Protein (DCP) of the raw materials. Whole maize (8.23 %DCP) Soya (45 % DCP) Omena (55 % DCP) and maize bran (7 % DCP) Sunflower (35 %DCP).
To make a 70 kg bag of feed
Layers require total crude protein content of at least 18 % to meet nutritional requirement.
34 kg of whole maize
12 kg of Soya
8 kg of omena
10 kg of maize bran
6 kg of Lime (as a calcium source)
Calculations
Whole maize = 34 kg x 8.23 ÷100 = 2.80kg
Soya bean = 12 kg x 45 ÷ 100 = 5.40 kg
Omena = 8 kg x 55 ÷ 100 = 4.40 kg
Maize bran = 10 kg x 7 ÷ 100 = 0.70 kg
Lime = 6 kg x 0 ÷ 100 = 0.00 kg
(Total crude protein 13.30 kg)
This means in 70 kg bag, the combined ingredients have a total crude protein content of (13.30÷70) x 100 = 19.0 % which is higher than the requirement of 18%.