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Bacterial resistance is a public and one health problem. Free‐living birds can be reservoirs of multidrug‐resistant bacteria and resistance genes. This study aimed to characterize the antimicrobial resistance of Escherichia coli isolated from free‐living urban pigeons (Columba livia) in South Brazil. Ninety‐two animals were sampled, and one isolate was obtained from each one. The isolates were characterized, and the antimicrobial resistance profile and beta‐lactam and colistin resistance genes were investigated. The isolates were classified as phylogroups B1 (35%), B2 (33%), A (16%) and D (16%), and 14% of the strains had the eae virulence gene. All isolates were resistant to at least one antimicrobial, and 63% of them were multidrug‐resistant. Geographical location where the pigeons were captured and presence of the eae gene were associated with multidrug resistance. blaVIM and mcr‐1 genes were detected in one and two isolates, respectively. This is the first report of these genes in E. coli of pigeons. The blaVIM‐positive isolate was classified as Shiga toxin‐producing E. coli, and the isolates with mcr‐1 were classified as Enterohaemorrhagic E. coli and Enteropathogenic E. coli, which raise additional concerns related to public health since these are zoonotic pathotypes. The results reveal that pigeons carry multidrug‐resistant pathogenic E. coli, which may interest public health. Nonetheless, further studies on whether these animals are sources of contamination for humans must be performed to understand their role in spreading antimicrobial resistance.

Mycobacterium tuberculosis var. bovis is the etiologic agent of animal tuberculosis (aTB), a neglected zoonotic disease. Animal tuberculosis can affect many species, including swine. aTB-consistent granulomas in these animals lead to carcass disposal, generating economic losses and posing risks to human health. In the present study, an aTB outbreak was identified at an intensive swine farming operation in Southern Brazil. Inspection during swine slaughter revealed aTB-suspected lesions, which were collected for diagnosis by histology, PCR, and bacterial isolation. The animals had no clinical signs of tuberculosis. Granulomatous lesions were identified in 0.73% (59/8,071) of the slaughtered swine, and were confirmed by histology. Nine samples were further examined by PCR and bacterial isolation, with 44.4% and 55.5% positive results, respectively. Data from abattoirs subjected to federal surveillance show an aTB prevalence in Brazil of <0.001%. The present data thus indicate a swine aTB outbreak in intensive breeding. Swine infection can be related to exposure to infected animals or to contaminated food or environment. Biosecurity measures must be taken to avoid aTB transmission. Although certified swine breeding farms adopt such measures, this report indicates that constant monitoring is crucial, and greater control in swine breeding and finishing units is required to prevent outbreaks and spread of tuberculosis.

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