УДК 636. 85. 13:637
From the data in the table of soy protein it had a high biological value and high coefficient of digestibility. After correlation of EAA/NEAA, calculations determined it an ,,ideal protein”, by the utilization coefficient ,,ideal protein” and after the Korpatsy method the closest plant to soy is green mass alfalfa. Corn grain practically after all approaches substantially yields to soy grains. The determination of BV protein of silo corn was set to the lowest possible index after the different methods of estimation which showed the necessity of scientific research in this direction with the purpose of improving forage from corn both after an amount protein and a biological value.
As the results of the research of professor V. G. Prudnikov and authors  coefficients of utility each of NEAA protein of milk of cows of holstein on rations without application of the gene-modified forage folded: lysin – 0,87; a methionine + cystein – 0,95; threonine – 1,0; valine – 0,88; leucine – 0,70; isoleucine – 0,86; phenilalanine + thirosine – 0,66, and ,,ideal protein” of milk of the same cows (%) : lysin – 117,6; a methionine + cystein – 97,1; threonine – 92,7; valine – 105,2; leucine – 132,3; isoleucine – 108,2; phenilalanine + thirosine – 137,0.
We consider that the result is given in relation to the biological value of protein which is a priority for the majority areas of forage areas in Ukraine and cows’ milk , the conducts of industry of holstein gotat normal terms can be in a certain measure by a standard and criterion in the case of appearance of biosafety from the side of provender foods.
Corn grains and especially corn silo on the indexes of biological value, their protein has a considerab yield to grain of soy and green mass of alfalfa.
It is impossible to confidently talk in relation to priority of that or other methods used by us, for the determination of the biological value of protein forage from corn in relation to ruminant animals, as these indexes of FАО/WOSH for the estimation of feed of people have been certificated.
Additional scientific research is needed in relation to the biological value protein of cows’ milk in the case of application of the gene-modified forage.
Key words: biosafety, biological value protein, forage, milk.