In principle, the basis of the ideal protein concept is based on Lysine, and the need for other amino acids in the amino acid / lysine ratio is determined. Therefore, the literature presents a large amount of information, ranging from production methods, digestibility in different species and economic viability.
Therefore, lysine is classified as the second limiting amino acid for poultry diets based on Maize and F. Soy. It is used almost exclusively for the deposition of body protein.
Ingrediente Lis total% |
|
Soy Protein Concentrate 4,04* |
|
F. de soy 46% 2,87* |
|
High grain corn Lis 0,35* |
Brazilian Poultry and Swine Table* |
Requirements and Antagonism
In this context, requirements are classified according to selected criteria. Where the requirement for weight gain is less than for breast gain, which subsequently is less for feed conversion.
Therefore, with the advancement of the ideal protein concept, the availability of lysine in its commercial form (L-Lysine) and at economically viable prices, its use has been stimulated by reducing the inclusion of crude protein.
However, excess lysine can be toxic and create antagonism with arginine. And this is because high amounts of lysine generates arginine deficiency, due to competition for reabsorption in the renal tube and an increase in the enzyme arginase.
As mentioned previously, L-Lysine is the reference for determining the ideal protein concept. in fact, it is necessary to pay attention to the correct demands of Lis. Since, any error in the determination of lysine, will result in an error in the determination of the other AA’s, with consequent loss of performance of the animals.
In addition, requirements may vary according to sex, genetics, ambience and well-being. Primarily males have higher demands than females, due to the greater potential for protein deposition.
Finally, the deficiency of lysine in the initial phase can delay the performance of the animal in the other phases, even with the correct balance in these.