Silage additives: Lentilactobacillus buchneri DSM 32651 (1k21903) authorised for all species — at least 1×10¹¹ CFU/g, dose 1×10⁸ CFU/kg of easy and moderately difficult to ensile forage; enumeration on MRS agar (EN 15787), identification by ERIC-PCR, sequencing or PFGE
Commission Implementing Regulation (EU) 2025/720, published on 16 April 2025, authorises until 6 May 2035 a preparation of Lentilactobacillus buchneri DSM 32651 as a technological additive in the functional group of silage additives for all animal species. It is based on the EFSA opinion of 18 September 2024: the strain is safe for animals, consumers and the environment, and at a dose of at least 1×10⁸ CFU/kg fresh material it can improve the aerobic stability of silage from material with a dry matter content of 28 % to 45 %.
- Conditions of the annex: composition at least 1×10¹¹ CFU/g additive (solid form), active substance — viable cells of the strain. The additive is to be used only in fresh plant material that is easy to ensile (more than 3 % soluble carbohydrates in fresh material) or moderately difficult (1.5–3.0 %), according to Regulation (EC) No 429/2008; minimum dose without other microorganisms 1×10⁸ CFU/kg. The additive is considered a potential skin and respiratory sensitiser — the act requires skin, eye and respiratory protection where procedures do not eliminate the risk.
- Analytical methods: strain identification — ERIC-PCR (enterobacterial repetitive intergenic consensus), DNA sequencing or pulsed-field gel electrophoresis (PFGE) according to CEN/TS 17697; enumeration in the additive — spread plate or pour plate on MRS agar according to EN 15787. According to EFSA, identity was established by digital DNA–DNA hybridisation (dDDH) on WGS data: 99.2 % similarity to the L. buchneri type strain DSM 20057T; no antimicrobial resistance genes above EFSA thresholds were found in the genome, and MIC values were below the cut-offs.
- Characterisation according to EFSA: five batches averaged 1.3×10¹¹ CFU/g (1.2–1.4×10¹¹); cadmium 0.011–0.012 mg/kg, lead 0.022–0.026 mg/kg, arsenic 0.013–0.014 mg/kg, mercury below the LOQ of 0.01 mg/kg, mycotoxins below the LOD. Dusting potential by the Stauber-Heubach method 1 039–11 395 mg/m³. Stability: no losses (below 0.5 log) for 24 months at −18 °C and 4 °C and for the first month at 20 °C; after 5 months at 20 °C two of three batches lost 0.9 and 1 log.
- Efficacy trials: six laboratory trials in minisilos (2.7 L or 1.75 L, five replicates, 20 °C, 90–103 days), doses 5.1×10⁷–1.0×10⁸ CFU/kg; aerobic stability was measured by the Honig method — as the time until the temperature rose 3 °C above the ambient 20 °C. According to EFSA, the additive improved it in a grass-legume mixture (45.0 % DM; 3.6 → 9.0 days) and in three trials with maize (28.3–33.9 % DM), and acetic acid rose in all treated silages; the range of 28–45 % DM follows from these materials. The act restricts use by carbohydrates, not dry matter — both criteria side by side.