Antimicrobial Resistance in Enterococci of Dairy Origin—A Review

Enterococci are ubiquitous lactic acid bacteria frequently detected in dairy environments, where they represent an important component of the non-starter lactic acid bacteria community, particularly in artisanal cheeses produced from raw milk. Due to their metabolic versatility, enterococci may contribute to cheese ripening and the development of characteristic sensory attributes; however, their technological relevance is accompanied by growing concern regarding their role as opportunistic pathogens and reservoirs of antimicrobial resistance. This review critically summarizes current knowledge on antimicrobial resistance in enterococci isolated from milk and dairy products, with emphasis on both intrinsic and acquired resistance traits and their reported prevalence across different dairy matrices and geographical regions. Particular attention is given to artisanal cheeses, in which heterogeneous and region-specific resistance patterns have been described. Advances in whole-genome sequencing have substantially improved understanding of the genetic basis of antimicrobial resistance in dairy enterococci and have largely corroborated earlier findings obtained through phenotypic antimicrobial susceptibility testing combined with targeted resistance gene detection. Nevertheless, available data remain fragmented due to variability in study design, analytical approaches, and reporting practices. Overall, the evidence highlights the need for harmonized surveillance strategies integrating phenotypic and genomic data within a One Health framework to improve risk assessment and to better understand the role of dairy enterococci in the dissemination of antimicrobial resistance along the food chain.