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The data should be converted to TSAA:Lys ratio for each treatment giving 100% equivalency of methionine as added between the DL and methionine hydroxy analogue sources. This would allow the reader to assess the data in context of how the reader is formulating diets and whether the data was generated below requirement, at requirement, or above requirement as the reader defines the requirement of their pigs.
Dr John, reports consistent with information available in the literature. I think it is relevant to make it clear that the use of the D-isomer of amino acids depends on the presence of the specific D-amino acid oxidase. Therefore, the efficiency of the use of methionine D isomers by pigs is directly related to the presence of the enzyme D methionine oxidase. These considerations were made since in the text and in Figure 3, this specificity does not appear.