Wild birds as reservoirs of multidrug-resistant enterobacteria in Mulungu, Brazil

Beleza, A. J. F.; Maciel, W. C.; Carreira, A. S.; Marques, A. R.; Nogueira, C. H. G.; Pascoal Filho, N. M.; Lima, B. P.; Silva, I. N. G. d.; Vasconcelos, R. H.; Ribeiro, L. R.; Teixeira, R. S. d. C.

doi:10.1101/2021.11.04.467336

bioRxiv · 10.1101/2021.11.04.467336

Wild birds as reservoirs of multidrug-resistant enterobacteria in Mulungu, Brazil

Beleza, A. J. F.·Maciel, W. C.·Carreira, A. S.·Marques, A. R.·Nogueira, C. H. G.·Pascoal Filho, N. M.·Lima, B. P.·Silva, I. N. G. d.·Vasconcelos, R. H.·Ribeiro, L. R.·Teixeira, R. S. d. C.

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Abstract

Caatinga is a biome unique to Brazil that is degraded by anthropogenic actions, which lead to the loss of biodiversity putting many species at risk of extinction. The Ceara State is located in the Caatinga and has a rich avifauna comprised of 433 species including 13 species that are threatened with extinction, which are found in the Baturite Massif. The aim of this study was to investigate the frequency and diversity of enterobacteria in wild birds and to determine their susceptibility to antimicrobials. Cloacal swab samples were collected from 50 individuals of 28 different species, including the Ceara Gnatheter (Conopophaga cearae) and Red-necked Tanager (Tangara cyanocephala cearensis), which are classified as vulnerable (VU) by the Brazilian Ministry of the Environment. A total of 55 isolates belonging to 14 different species of Enterobacteriaceae were identified. Among these, Pantoea agglomerans and Escherichia coli were the most prevalent species with isolation rates of 36% and 26%, respectively. The highest rate of antimicrobial resistance found was to ampicillin (41.8%), followed by nalidixic Acid (36.3%) and amoxicillin associated with clavulanic acid (32.7%). The drugs with the best efficacy were tobramycin (96.4%), ciprofloxacin (92.6%) and tetracycline (90.9%). Multidrug resistance was observed in 23.5% of the analyzed strains. This research provides important information about the composition of the cloacal microbiota of wild birds in Mulungu, Brazil, as well as their health status. In addition, these results demonstrate that they harbor multidrug-resistant strains of Enterobacteriaceae.

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Beleza, A. J. F., Maciel, W. C., Carreira, A. S., Marques, A. R., Nogueira, C. H. G., Pascoal Filho, N. M., Lima, B. P., Silva, I. N. G. d., Vasconcelos, R. H., Ribeiro, L. R., Teixeira, R. S. d. C.. 2021-11-04. Wild birds as reservoirs of multidrug-resistant enterobacteria in Mulungu, Brazil. https://doi.org/10.1101/2021.11.04.467336

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