Genetically isolated strain of Lacticaseibacillus huelsenbergensis, identified by the code DSM 115424, has been discovered or identified.
The European Union Reference Laboratory (EURL) has provided guidelines for the official control of *Lacticaseibacillus huelsenbergensis* DSM 115424, a microbial strain commonly used in feed additives and silage.
### Identification Methods
The EURL recommends Whole Genome Sequencing (WGS) as the primary method for unequivocal identification of *Lacticaseibacillus huelsenbergensis* DSM 115424. This technique allows for exact strain-level discrimination by comparing the genome sequence of the tested sample with the reference strain’s genome. For preliminary or complementary identification, strain-specific PCR assays can be used, but these should be confirmed by WGS for official control purposes.
### Quantification Methods
Quantitative analysis of viable cells in feed additives and silage typically employs standard microbiological plate counting techniques on selective media suitable for lactobacilli. The EURL advises using validated culture media and incubation conditions that favour the growth of *Lacticaseibacillus huelsenbergensis* while inhibiting contaminants. Alternative quantification methods like flow cytometry or quantitative PCR (qPCR) may be used for rapid enumeration, but these require rigorous validation against plate counts for accuracy and specificity.
### Detection in Silage and Feed Additives
Proper homogenization and dilution of silage or feed additive samples are crucial to ensure representative and reproducible detection. Positive isolates from culture-based methods should be confirmed by molecular techniques (e.g., PCR, WGS) to verify the identity of *Lacticaseibacillus huelsenbergensis* DSM 115424.
In summary, the EURL guidelines provide a comprehensive approach to the official control of *Lacticaseibacillus huelsenbergensis* DSM 115424 in feed additives and silage. Following these guidelines ensures reliable identification and quantification, supporting regulatory compliance and safety.
For further information or detailed protocol summaries, feel free to ask! It's worth noting that the EURL does not require further testing or validation of the methods. The feed additive containing the strain Lacticaseibacillus huelsenbergensis DSM 115424 is intended for use with all animal species, and the recommended dosage for adding the feed additive to fresh silage is 1 x 10 CFU/g. The ring-trial validated EN 15787 method is the recommended method for the enumeration of Lacticaseibacillus huelsenbergensis DSM 115424 in the feed additive for official control. The authorization for the use of the feed additive for all animal species is sought under the current application. The EURL has stated that it cannot evaluate nor recommend any method for the unambiguous determination of Lacticaseibacillus huelsenbergensis DSM 115424 added to silage. The application seeks authorization for Lacticaseibacillus huelsenbergensis DSM 115424 under Article 4, category 1(k) 'technological additives' / 'silage additives'.
The European Union Reference Laboratory (EURL) recommends integrating science-based health-and-wellness strategies in the field of animal nutrition by employing Whole Genome Sequencing (WGS) for the identification and official control of Lacticaseibacillus huelsenbergensis DSM 115424 in therapies-and-treatments such as feed additives and silage. For instance, the ring-trial validated EN 15787 method, a quantification method, is the recommended approach for the enumeration of Lacticaseibacillus huelsenbergensis DSM 115424 in the feed additive for official control purposes. This supports the safety and efficacy of animal feed and contributes to the overall well-being of the animals.
