In forages an algorithm used to establish the presence of an “ideal” protein is developed for pigs on the basis of the data on norms of the content of essential amino acids in compound feeds and their contents in the basic forages. The interrelation of the first limiting amino acid with norm of requirement compounds number of complete sets of an “ideal” protein in a forage. Under the content ranging of forages is made to them of an “ideal” protein and its cost. In the manufacture of pork the greatest food costs , are going to energy and forage protein. The animals unequally use the proteins of forages. The over expenditure of a protein on manufacture of cattle-breeding production explains by losses amino-acids owing to their surplus concerning a level first limiting amino-acid.
It was proved, that the definition of a level of amino-acids of structure of forages to norms of the contents irreplaceable amino-acids in compound feeds for pigs allows us to give a closer estimation of amino-acids and nutritiousness of forages.
First limiting amino-acid in a grain of cereal cultures, and raps, sunflower meal is lysine, second – threonine except for corn, at which second limiting amino-acid is tryptophan, and at raps and sunflower meal – leucine.
Key word: Feeding of pigs, amino-acids, protein, ideal protein, compound feeds.