Bacillus paralicheniformis DSM 33902 and Bacillus subtilis DSM 33903 for dairy ruminants (4b1896) until 1 January 2036: enumeration on tryptone soya agar to EN 15784, 3.8 × 10⁸ CFU/kg feed or 7.4 × 10⁷ CFU/l water and 9.6 × 10⁹ CFU/animal/day; erythromycin MIC > 16 mg/l without acquired genes
Commission Implementing Regulation (EU) 2025/2511, published on 12 December 2025, authorises until 1 January 2036 a preparation of spores of two Bacillus strains (holder: Chr. Hansen A/S, product Bovacillus™) as a gut flora stabiliser for ruminants for milk production or reproduction, also in water for drinking. In its opinion of 9 April 2025 EFSA found it safe and potentially efficacious in dairy cows; it does not irritate skin or eyes but is a skin and respiratory sensitiser. For water EFSA proposed a dose per animal, because no fixed feed-to-water ratio can be set for ruminants — the act gives both a concentration in water and a daily dose.
- Methods in the annex: enumeration in the additive, compound feed and water for drinking — spread plate on tryptone soya agar (EN 15784); identification — DNA sequencing or PFGE (CEN/TS 17697). Additive: at least 3.2 × 10¹⁰ CFU/g Bacillus spp. in a 1:1 ratio; minimum 3.8 × 10⁸ CFU/kg complete feed or 7.4 × 10⁷ CFU/l water, and in water a dose of at least 9.6 × 10⁹ CFU/animal/day. Information on stability to heat treatment and in water is required; respiratory and skin protection.
- Strains: B. paralicheniformis from soil (ANI 98.6 % with the type strain KJ-16T; spores pasteurised), B. subtilis from soybean mash (ANI 97.7 % with B. subtilis 168T). MICs for B. paralicheniformis: chloramphenicol and clindamycin one dilution above the cut-off, erythromycin > 16 against 4 mg/l; analysis of the hits in ResFinder and NCBI (four and two) found no acquired resistance genes. Cytotoxicity test on Vero cells — no lysis; the B. paralicheniformis supernatant did not inhibit the reference strains, which rules out bacitracin at levels of concern.
- Two forms: Bovacillus™ 10 (calcium carbonate carrier, for feed) — 4.6 × 10¹⁰ CFU/g on average, arsenic 0.48, lead 0.77, cadmium 0.13 mg/kg, dusting potential 1886 mg/m³ (943–2480); Bovacillus™ WS (maltodextrin, for water) — 4.3 × 10¹⁰ CFU/g, dusting potential 1149 mg/m³. Pelleting at 75, 85 and 95 °C for 30 s — losses < 0.5 log; homogeneity CV in feed pelleted at 85 °C — 15 %; in water at 25 °C for 48 h no losses. Irritation: OECD TG 404 and TG 438 for form 10, for WS a conclusion by analogy.
- Efficacy: three trials in cows (Holstein-Friesian and crosses with Swedish Red, 12–15 weeks, 68–76 cows) — in trial 1 better ECM efficiency (1.72 vs 1.67), in trial 2 higher milk yield (41.3 vs 40.1 kg/d) and feed efficiency (1.52 vs 1.48), in trial 3 feed efficiency 1.59 vs 1.54; no effect on milk composition. Significance was set at p < 0.10, and the calculated feed concentrations were 3.08–3.41 × 10⁸ CFU/kg against the intended 3.8 × 10⁸.