Resistance to β-lactam antibiotics in Aeromonas hydrophila isolated from rainbow trout (Onchorhynchus mykiss) Authors Maria José Saavedra Department of Veterinary Sciences, CECAV-University of Trás-os- Montes e Alto Douro, Portugal Sandra Guedes-Novais Department of Veterinary Sciences, CECAV-University of Trás-os- Montes e Alto Douro, Portugal Anabela Alves Department of Veterinary Sciences, CECAV-University of Trás-os- Montes e Alto Douro, Portugal Paulo Rema Department of Animal Production, University of Trás-os-Montes e Alto Douro and CIMAR, University of Porto, Portugal Marta Tacão Department of Biology, Center for Cell Biology, University of Aveiro, Portugal António Correia Department of Biology, Center for Cell Biology, University of Aveiro, Portugal Antonio Martínez-Murcia Molecular Diagnostics Center (Biomolecular Technologies, S.L.); and University Miguel Hernández, Orihuela, Alicante, Spain Keywords: Aeromonas hydrophila, antibiotic resistance in fish, rainbow trout (Oncorhynchus mykiss) Abstract Bacterial infections caused by members of the genus Aeromonas, with a relatively high antibiotic resistance, are among the most common and troublesome diseases of fish raised in ponds with recirculation systems. In this study, carried out at an experimental aquaculture station in northern Portugal, 51 strains identified as belonging to the genus Aeromonas were isolated from 20 rainbow trout (Oncorhynchus mykiss) skin and kidney samples, as well as from raceway water samples. Macro- and microscopic examination of the fish tissues revealed lesions or cellular alterations in skin and kidney that seemed to correlate with the presence of those isolates. The sensitivity of all isolated strains to different groups of β-lactam antibiotics (penicillins, cephalosporins, monobactams and carbapenems) was evaluated using the disc diffusion method. The highest rates of resistance were to amoxicillin, carbenicillin and ticarcillin. Unexpected resistance to imipenem, an antibiotic of clinical usage, was also detected, which suggests that resistance may have been transferred to the Aeromonas population from the environment. [Int Microbiol 2004; 7(3):207–211] Downloads PDF Published 2010-02-28 Issue Vol. 7 No. 3 (2004) Section Research Articles License Submission of a manuscript to International Microbiology implies: that the work described has not been published before, including publication in the World Wide Web (except in the form of an Abstract or as part of a published lecture, review, or thesis); that it is not under consideration for publication elsewhere; that all the coauthors have agreed to its publication. The corresponding author signs for and accepts responsability for releasing this material and will act on behalf of any and all coauthors regarding the editorial review and publication process.If an article is accepted for publication in International Microbiology, the authors (or other copyright holder) must transfer to the journal the right–not exclusive–to reproduce and distribute the article including reprints, translations, photographic reproductions, microform, electronic form (offline, online) or any other reproductions of similar nature. Nevertheless, all article in International Microbiology will be available on the Internet to any reader at no cost. The journal allows users to freely download, copy, print, distribute, search, and link to the full text of any article, provided the authorship and source of the published article is cited. The copyright owner's consent does not include copying for new works, or resale. In these cases, the specific written permission of International Microbiology must first be obtained.Authors are requested to create a link to the published article on the journal's website. The link must be accompanied by the following text: "The original publication is available on LINK at <http://www.im.microbios.org>. Please use the appropiate URL for the article in LINK. Articles disseminated via LINK are indexed, abstracted, and referenced by many abstracting and information services, bibliographic networks, subscription agencies, library networks, and consortia.
