RT Journal Article T1 Antimicrobial activity, molecular typing and in vitro safety assessment of Lactococcus garvieae isolates from healthy cultured rainbow trout (Oncorhynchus mykiss, Walbaum) and rearing environment A1 Contente, Diogo A1 Campanero, Cristina A1 Arbulu, Sara A1 Saralegui, Claudia A1 Del Campo, Rosa A1 Feito Hermida, Javier A1 Gómez Sala, Beatriz A1 Dias Araújo, Carlos Alexandre A1 Peña Vidal, Nuria A1 Muñoz Atienza, Estefanía A1 Borrero Del Pino, Juan A1 Hernández Cruza, Pablo Elpidio A1 Cintas Izarra, Luis Miguel AB Lactococcus garvieae is the aetiological agent of lactococcosis, an ichthyopathology affecting rainbow trout (Oncorhynchus mykiss, Walbaum) farming and having recently been considered as a potential food-borne zoonotic agent. This work aims to characterise a population of 53 L. garvieae isolates from healthy cultured rainbow trout and rearing environment by using microbiological, biochemical and genetic assays to unveil the potential impact that their presence may have, not only for fish, but also for consumers. The lactococci exhibited a broad antimicrobial spectrum against Gram-negative ichthyopathogens, likely due to production of organic acids. The 53 L. garvieae isolates were grouped into two and five genetic clusters by PFGE and ERIC-PCR, respectively. All the lactococcal isolates produce α-haemolysis and harbour, at least, 10 putative virulence factors (hly-1, hly-2, hly-3, NADH oxidase, sod, pgm, adhPsaA, eno, LPxTG-3 and adhCI). While all the lactococci were resistant to streptomycin and clindamycin, no resistance genes were found. The manuscript concludes that the non-existence of active lactococcosis does not guarantee the absence of potentially virulent L. garvieae, which also exhibit a great capacity for adaptation and persistence in the environment. Furthermore, the antibiotic resistance profile shown may lead to re-evaluate the treatments of choice in human patients. PB Elsevier SN 0023-6438 YR 2022 FD 2022 LK https://hdl.handle.net/20.500.14352/108721 UL https://hdl.handle.net/20.500.14352/108721 LA eng NO Feito, J., Araújo, C., Gómez-Sala, B., Contente, D., Campanero, C., Arbulu, S., Saralegui, C., Peña, N., Muñoz-Atienza, E., Borrero, J., Del Campo, R., Hernández, P. E., & Cintas, L. M. (2022). Antimicrobial activity, molecular typing and in vitro safety assessment of Lactococcus garvieae isolates from healthy cultured rainbow trout (Oncorhynchus mykiss, Walbaum) and rearing environment. LWT, 162, 113496. https://doi.org/10.1016/j.lwt.2022.113496 NO Ministerio de Ciencia, Innovación y Universidades (España) NO Universidad Complutense de Madrid NO Comunidad de Madrid NO Fundación Mutua Madrileña DS Docta Complutense RD 22 abr 2025