<p>Biofilm-related infections pose a critical challenge in veterinary medicine, driving antimicrobial resistance (AMR) and undermining livestock, poultry, and aquaculture productivity. Conventional antibiotics are often ineffective against biofilms, highlighting the need for novel alternatives. Bacteriocins, ribosomally synthesized antimicrobial peptides produced mainly by lactic acid bacteria, offer broad-spectrum activity, stability, and minimal cytotoxicity. This review outlines their multifaceted mechanisms, ranging from inhibition of microbial adhesion and quorum sensing to disruption of membranes and extracellular matrices, which make them promising tools against biofilm-forming pathogens. Evidence across veterinary sectors demonstrates their potential to mitigate mastitis, swine enteric diseases, poultry colibacillosis, and aquaculture infections. Synergistic applications with antibiotics, nanoparticles, and other antimicrobials further enhance efficacy and reduce antibiotic dependence. This article critically synthesizes cross-sector evidence from livestock, poultry, and aquaculture while also introducing a unique mechanistic classification of bacteriocin action against biofilms. By integrating veterinary and One Health perspectives, it highlights translational gaps and practical pathways that have not been systematically addressed before. However, translation into practice remains limited by the absence of standardized biofilm models, insufficient in vivo validation, gaps in pharmacokinetics, and scarce farm-level trials. A structured pipeline from discovery to commercialization, embedded within the One Health framework, will be essential to advance bacteriocins as sustainable biotherapeutics for veterinary and public health.</p>