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Dr. Yves, results of studies we conducted with layers, and those of some literature data, which were consistent with ours, showed that the relationship. met + cist.dig: lysine dig, which corresponded to 100: 100, provided the best performance results for birds. Based on these considerations, I found that in the ration used in your work the relationship between these amino acids was below that relationship, which leads to the deduction that probably the level of dig lysine. used may be overestimated. My considerations do not invalidate your study and do not have this claim. What we are aiming for with these statements is to encourage more researchers in this line of research. This has relevance, considering that the level of dig lysine. really overestimated, in addition to correcting it, there would be a need to reevaluate the relationships of the other essential amino acids with lysine to establish the ideal protein for the category under study.