Escherichia coli and Antibiotic Resistance in Swine Farming: Implications for Public Health
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Rui Cordeiro
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Microbiology and Antibiotic Resistance Team (MicroART), Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro (UTAD)
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LAQV-REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade Nova de Lisboa, Caparica, Portugal
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Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
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Functional Genomics and Proteomics Unit, University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal.
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Microbiology and Antibiotic Resistance Team (MicroART), Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
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Functional Genomics and Proteomics Unit, University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
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Intergados, SA, Av. de Olivença, S/N 2870-108 Montijo, Portugal
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REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto
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Chemistry Research Centre (CQ-VR), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal.
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National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections (NRL-AMR/HAI), Department of Infectious Diseases, National Institute of Health Dr Ricardo Jorge
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Centre for the Studies of Animal Science, Institute of Agrarian and Agri-Food Sciences and Technologies, Oporto University
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CECAV – Veterinary and Animal Research Centre, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
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Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), Portugal
Academic Editor: Marc Maresca
Abstract: In swine farming, E. coli plays a critical role in transmitting multi-drug resistance (MDR). Antibiotic use in swine management promotes antibiotic-resistant bacteria emergence, limiting treatment options and spread through food-chain. The aim of this study is investigating the role of E. coli, focusing on MDR, genotypic analysis, Multi-Locus Sequence Typing (MLST), and phylogenetic analysis from different pig farms.
Fifty-nine swine fecal samples were obtained from 12 pig farms, yielding 47 E. coli isolates. Of these, 44 were from breeding pigs, distributed as different compartments. Eight samples from fattening pigs yielded two E. coli strains. Antibiotic resistance was observed in all 46 E. coli isolates tested, with high resistance to tetracycline (100%), ampicillin (97.8%), tobramycin (97.8%), and trimethoprim-sulfamethoxazole (95.7%). MDR was common, with 9 isolates resistant to four antibiotic classes, 18 to five, 13 to six, and 6 to seven classes. In genotypic analysis, ampC gene was predominant (86.95%), followed by blaTEM (60.86%), sul3 (60.86%). For MLST, we selected 7 strains resulting in the identification of 6 STs: ST101, ST5229, ST48, ST5757, ST10, and ST1147. Phylogroup A dominated at 60.8%, followed by B1 at 30.4%, and D at 8.69%.
High rates of resistance were observed and MDR was widespread, with resistant to multiple antibiotic classes. Overall, this study highlights the urgent need for surveillance and intervention strategies to mitigate the transmission of antibiotic-resistant E. coli from swine to humans, protecting both animal and public health in the context of swine farming practices.
Keywords: Antimicrobial resistance; swine herds; multidrug-resistance; food-safety
