Saccharomyces cerevisiae NBRC 0203 and Lacticaseibacillus rhamnosus NBRC 3425

In the current application an authorisation is sought under Article 4(1) for Saccharomyces
cerevisiae NBRC 0203 and Lacticaseibacillus rhamnosus NBRC 3425 under the category / functional group 1(k) 'technological additives' / 'silage additives', according to Annex I of Regulation (EC) No 1831/2003. The authorisation is sought for the use of the feed additive for all animal species. According to the Applicant, the feed additive is liquid and contains Saccharomyces cerevisiae NBRC 0203 and Lacticaseibacillus rhamnosus NBRC 3425 as active substances at a minimum amount of 5 x 10³ and 4 x 10⁷ Colony Forming Unit (CFU) / ml feed additive, respectively. The feed additive is intended to be sprayed on the forage, used for ensiling process at a recommended minimum dosage that corresponds to 80 mg/kg fresh silage. For the identification of Saccharomyces cerevisiae NBRC 0203 the EURL recommends for official control DNA sequencing methods or the polymerase chain reaction (PCR) amplification method, a generally recognised methodology for the identification of probiotic yeast. This method was ring-trial validated and became the CEN technical specification CEN/TS 15790. For the identification of Lacticaseibacillus rhamnosus NBRC 3425 at strain level the EURL recommends for official control DNA sequencing methods or Pulsed-Field Gel Electrophoresis (PFGE) (CEN/TS 17697). For the enumeration of Saccharomyces cerevisiae NBRC 0203 in the feed additive the Applicant proposed for official control the recently revised ring-trial validated EN 15789 method dedicated for the enumeration of Saccharomyces cerevisiae in feedingstuffs (additives, premixtures and compound feeds excluding mineral feeds) that contain Saccharomyces cerevisiae as a single microorganism component or in a mixture with other microorganisms. The following performance characteristics are reported in the frame of the ring-trial validation studies when using pour plate method with YGC agar, after logarithmic transformation of CFU values ranging from 7.13 to 7.48 log₁₀ CFU/g: a standard deviation for repeatability (S_r) ranging from 0.17 to 0.36 log₁₀ CFU/g and a standard deviation for reproducibility (S_R) ranging from 0.55 to 0.60 log₁₀ CFU/g. Based on the performance characteristics available, the EURL recommends for official control the ring-trial validated EN 15789 method for the enumeration of Saccharomyces cerevisiae NBRC 0203 in the feed additive. For the enumeration of Lacticaseibacillus rhamnosus NBRC 3425 in the feed additive the Applicant proposed for official control the recently revised ring-trial validated EN 15787 method dedicated for the enumeration of lactobacilli spp. in feedingstuffs (additives, premixtures and compound feeds excluding mineral feeds) that contain lactobacilli as a single microorganism component or in a mixture with other microorganisms. The following performance characteristics, expressed in terms of precision, are reported in the frame of the ring-trial validation studies after logarithmic transformation of the CFU values ranging from 7.40 to 8.03 log₁₀ CFU/g: a standard deviation for repeatability (S_r) ranging from 0.10 to 0.26 log₁₀ CFU/g and a standard deviation for reproducibility (S_R) ranging from 0.18 to 0.39 log₁₀ CFU/g. Based on the performance characteristics available, the EURL recommends for official control the ring-trial validated EN 15787 method for the enumeration of Lacticaseibacillus rhamnosus NBRC 3425 in the feed additive. As the unambiguous determination of Saccharomyces cerevisiae NBRC 0203 and Lacticaseibacillus rhamnosus NBRC 3425 added to silage is not achievable by analysis, the Applicant did not provide any specific method. Therefore, the EURL cannot evaluate nor recommend any method for official control to enumerate Saccharomyces cerevisiae NBRC 0203 and Lacticaseibacillus rhamnosus NBRC 3425 in silage. Further testing or validation of the methods to be performed through the consortium of National Reference Laboratories as specified by Article 10 (Commission Regulation (EC) No 378/2005, as last amended by Regulation (EU) 2015/1761) is not considered necessary.