Probiotic Promise, Safety Snag: EFSA Gives Mixed Verdict on Multi-Strain Dog Feed Additive

Not all that glitters in the world of pet probiotics is gold—and sometimes, even a blend of well-known “good bacteria” can carry hidden risks. On December 9, 2025, the European Food Safety Authority (EFSA) delivered a nuanced scientific opinion on FlorEquilibre® Chien, a multi-strain feed additive intended to support canine gut health. While parts of the formulation passed safety scrutiny, a critical red flag emerged—casting doubt not only on its approval but also on how microbial safety is assessed in companion animal nutrition.

Developed as a zootechnical additive in the functional category of gut flora stabilisers, FlorEquilibre® Chien contains five live bacterial strains:

• Lactobacillus acidophilus CNCM I-3231
• Ligilactobacillus salivarius CNCM I-3233
• Lactiplantibacillus plantarum CNCM I-3232
• Lacticaseibacillus rhamnosus CNCM I-4427
• Bifidobacterium animalis subsp. lactis CNCM I-3993

Four of these—all the lactobacilli—were deemed suitable for EFSA’s Qualified Presumption of Safety (QPS) approach. Their identities were confirmed, and crucially, no acquired antimicrobial resistance (AMR) genes were detected. For these strains, the FEEDAP Panel concluded they are presumed safe for dogs and the environment.

But the fifth strain—Bifidobacterium animalis subsp. lactis CNCM I-3993—told a different story. The panel found that this widely used probiotic harbours an acquired antimicrobial resistance gene, raising serious concerns. As a result, its use is considered unsafe for the target species (dogs), users, and the environment. This single finding undermines the entire product’s safety profile, since additives must be safe in their complete formulation.

Adding to the caution, EFSA flagged significant occupational hazards: the additive is an eye irritant and a skin and respiratory sensitizer. Exposure via any route—inhalation, skin contact, or eye contact—is considered a risk, demanding strict handling protocols for manufacturers and veterinarians alike.

Perhaps most telling is what EFSA didn’t say: it could not conclude on the efficacy of the additive for dogs. Despite marketing claims about gut balance and digestive support, the submitted data failed to demonstrate a measurable benefit. In regulatory terms, that means even if safety issues were resolved, the product would still lack proof of function—a double setback.

This opinion highlights a growing tension in pet nutrition: the rush to commercialize human-inspired probiotics without rigorous species-specific validation. While B. animalis subsp. lactis is common in human yogurts and supplements, its genetic stability and AMR status in veterinary contexts cannot be assumed safe by association. EFSA’s stance reaffirms a core principle: every strain, in every application, must prove its safety independently.

For pet owners seeking gut health solutions, the message is clear: not all probiotics are created equal, and “natural” doesn’t automatically mean “safe.” For regulators, it’s a reminder that microbial additives—especially those crossing from human to animal use—demand genomic vigilance.

In the end, FlorEquilibre® Chien stands as a case study in complexity: a blend of beneficial microbes shadowed by one problematic strain, approved science meeting commercial ambition, and the ever-present need to put safety before trend—even when the label says “probiotic.”