Preparation of chromium chelate of DL-methionine

What it is. Zootechnical additive from functional group 4d consisting of a chromium(III) chelate with dl-methionine, obtained by chemical preparation. The declared composition combines 1.8 to 2.2 % chelate (at least 1,000 mg Cr(III)/kg of additive) and a coloured microtracer (iron coated with tartrazine and shellac). The additive is in solid form.

What it is for. This type of additive is generally used as a supplementary source of chromium in organic chelated form, intended for salmonids. It belongs to the other zootechnical additives group (4d), a category associated with effects on zootechnical performance. It is typically used at premix or complete feed level, according to formulation practices for this target species.

Points to watch. The composition requires a chelate content of 1.8 to 2.2 % of the additive and a maximum nickel impurity of 1.33 mg/kg of additive; authorisation is limited to salmonids and expires on 30/09/2035. The chelated structure and chromium level must be verified by the prescribed analytical methods (ICP-MS, ICP-AES, IEC-VIS, mid-infrared), and the microtracer incorporation rate must be checked to ensure mixture homogeneity.