Detection of ESBL-producing strains at the veterinary necropsy environment1

Abstract

- Pinto L.B., Holmström T.C.M., David L.A., Mendes M.B., Makita M.T., Rochade-Souza C.M., Brito M.F., Melo D.A. & Souza M.M.S. 2025. Detection of ESBL-producing strains at the veterinary necropsy environment. Pesquisa Veterinária Brasileira 45:e07501, 2025. Laboratório de Bacteriologia Veterinária, Departamento de Microbiologia e Imunologia Veterinária, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Rodovia BR-465 Km 7, Seropédica, RJ 23890-000, Brazil. E-mail: theresseholmstrom@yahoo.com.br The emergence and spread of resistance to antimicrobials is one of the three main threats to public health in the 21st century. It must be analyzed using an integrated One Health approach, as it is a health risk shared by people, animals, and the environment. Among these, the necropsy space represents a point of cohesion, being an extremely relevant place for research and understanding the circulation of the bacterial microbiota and its resistance genes. The present study evaluated the occurrence of superbugs in samples from animals necropsied at the Federal Rural University of Rio de Janeiro, considering the priority criteria established by the World Health Organization (WHO). Of the 198 samples collected from 45 animals, 20 pet animals, 20 production animals and three wild animals, 325 strains were isolated, of which 51.38% (167/325) were Enterobacterales, 31.69% (103/325) Staphylococcus spp., 12.62% (41/325) Enterococcus spp., 2.46% (8/325) Streptococcus spp. and 1.85% (6/325) non-fermenting Gram-negative bacilli (NFGNB). In 29.13% (30/103) of Staphylococcus spp., the blaZ gene was detected, and in enterobacteria, the presence of blaSHV was detected in 10.18% (17/167), blaTEM in 6.59% (11/167) and blaCTX-M-1 in 4.19% (7/167). These results reveal the occurrence of species characterized as critical superbugs by the WHO in the necropsy environment and reinforce the need to monitor these strains in the veterinary environment not only for the adoption of appropriate control and treatment measures for animals but also for the implementation of protocols safe for the disposal of their carcasses.