J Appl Microbiol. 2022 Jan 22. doi: 10.1111/jam.15461. Online ahead of print.
ABSTRACT
AIMS: Worldwide, studies regarding antimicrobial resistance in rabbits are scarce. In addition, it seems that rearing conditions have important impact on emergence and spread of antimicrobial resistant bacteria. Thus, the authors sought to 1.) assess the role of rabbits residing across diverse ecosystems as potential reservoirs of antimicrobial-resistant enterococci and 2.) investigate the genetic background of detected resistances.
METHODS AND RESULTS: Faecal samples from 60 healthy farmed rabbits (one farm), 35 laboratory rabbits, and 31 wild rabbits were analyzed. Overall, 97 enterococci isolates were accumulated, as follows: 44 E. faecium, 37 E. faecalis, 7 E. gallinarum, 5 E. durans, and 4 E. avium. E. faecalis isolates were statistically associated with farm rabbits and wild rabbits (P < 0.05). High rates of resistance were observed for tetracycline [60.8%; tetM (n = 48; 81.3%), tetO (n = 7; 11.8%), and tetL (n = 1; 1.7%)], erythromycin [43.3%; msr(A) (n = 14; 33.3%) and ermB (n = 13; 31%)], ampicillin [29.9%], streptomycin [26.8%; ant(6)-Ia (n = 3, 11.5%)] , and vancomycin [21.6%; vanA (one E. faecium + one E. faecalis; 9.5%)]. Low frequencies of resistance were observed for teicoplanin [9.2%], linezolid [8.2%], ciprofloxacin [7.2%], and gentamicin [1%; aac(6′)-Ie-aph(2″)-Ia]. Resistance to ampicillin, and vancomycin was associated with laboratory rabbits (P < 0.05). Int-Tn (Tn916/1545) was detected in 27 (27.8%) isolates, of which ten isolates co-harbored tetM and ermB genes, while 16 comprised tetM.
CONCLUSION: Findings indicate that clinically relevant enterococci species isolated from rabbits are frequently resistant to antimicrobials and harbor a range of genes associated with the Tn916/1545 family.
SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlights high rates of antimicrobial-resistant enterococci from rabbits and the occurrence of both vancomycin- and linezolid- resistant isolates, potentially representing a very serious threat to human and animal health.
PMID:35064986 | DOI:10.1111/jam.15461
