Saccharomyces cerevisiae NCYC R618

In the current application an authorisation is sought under Article 4 for Saccharomyces cerevisiae NCYC R618 under the category / functional group 4 (b) "zootechnical additives" / "gut flora stabilisers", according to Annex I of Regulation (EC) No 1831/2003. The authorisation is sought for the use of the feed additive for chickens for fattening and all other avian species reared for laying and fattening.
The active substance of the feed additive is consisting of viable cells of Saccharomyces cerevisiae strain NCYC R618 with a minimum content of 4.0 x 1012 Colony Forming Unit (CFU) / kg feed additive.
The feed additive is intended to be used directly in compound feed or through premixtures. The Applicant did not propose any inclusion levels of the additive or the active substance in compound feed, however the recommended levels of the feed additive are ranging from 1 to 2 g / kg compound feed.
For the identification of Saccharomyces cerevisiae NCYC R618, the Applicant applied sequencing of the variable D1/D2 region of the nuclear encoded 26S ribosomal DNA. However, the EURL recommends for official control 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 enumeration of Saccharomyces cerevisiae NCYC R618 in the feed additive, premixtures and compound feed the Applicant proposed the ring-trial validated EN 15789 method, which was recently revised by CEN resulting in updated method dedicated for the enumeration of Saccharomyces cerevisiae in feed additives, premixtures and compound feed (with exclusion of mineral feed) containing Saccharomyces cerevisiae as a single microorganism 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 (Sr) ranging from 0.17 to 0.36 log10 CFU/g and a standard deviation for reproducibility (SR) ranging from 0.55 to 0.60 log10 CFU/g. In addition, depending on whether pour or spread plate methods are used, the lowest limit of quantification (LOQ) of 1x105 CFU and 4x105 CFU / kg compound feed, respectively can be derived following the protocol of EN 15789 standard method and applying the provisions of EN ISO 7218 and EN 15789 methods. 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 NCYC R618 in the feed additive, premixtures and compound feed.

Note: The EN 15789 method is not applicable to mineral feeds containing at least 40 % (w/w) of crude ash. For these matrices laboratories may consider the validated 28.2.6 VDLUFA method.

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.