EU Proposes New Lysine Testing Standards for Animal Feed and Water

New recommendations have been issued for testing lysine in animal feed and water. The European Union Reference Laboratory (EURL) has proposed specific methods for measuring lysine levels in different substances. These guidelines cover feed additives, premixtures, compound feed, and drinking water for livestock. The authorisation request includes L-lysine monohydrochloride, liquid L-lysine, and L-lysine produced via fermentation using Corynebacterium glutamicum strains KCCM 80368 or KCCM 80479. These additives are intended for all animal species under two functional groups: nutritional additives (amino acids and salts) and sensory additives (flavouring compounds). They can be mixed into feed through premixtures, complementary feed, or added directly to compound feed and drinking water.

The EURL recommends the EN ISO 17180 method for determining free lysine in feed additives and premixtures containing over 10% lysine. For premixtures and compound feed, it suggests a ring-trial validated EU method based on IEC-VIS. The same IEC-VIS approach is advised for measuring lysine in water. Additionally, the Food Chemical Codex (FCC) monograph is proposed for identifying L-lysine monohydrochloride in feed additives.

The applicant has also put forward a modified version of the EU method for lysine testing in feed additives. Minimum lysine content requirements are set at 78% (w/w, dry matter) for L-lysine monohydrochloride and solid L-lysine, and 50% (w/w) for concentrated liquid L-lysine. When used as a flavouring compound, the maximum allowed concentration is 25 mg/kg in compound feed. These recommendations provide clear testing standards for lysine in animal nutrition. The proposed methods ensure accurate measurement across different feed types and water sources. The authorisation, if granted, will apply to a wide range of livestock under EU regulations.