Detection of bacteria and fungi and assessment of the molecular aspects and resistance of Escherichia coli isolated from confiscated passerines intended for reintroduction programs

• A high occurrence of Enterobacteria was observed.
• Staphylococcus, Micrococcus, Escherichia coli and Klebsiella were most frequently isolated.
• E. coli showed multidrug-resistance and low occurrence of genes encoding virulence factors.
• Risks related to the dissemination of Salmonella, Cryptococcus and Candida were low.
• These animals may represent a low risk for the transmission of EPEC, APEC, UPEC and NMEC.

Many native bird species are currently considered rare in Brazil because they have been indiscriminately collected by animal traffickers and commercialized, leading to dwindling numbers in their natural habitats. Confiscated animals are at times destined for reintroduction programs that must ensure these animals do not pose a risk to native populations. Healthy or sick wild passerines may carry a great diversity of microorganisms. Therefore, knowledge of the sanitary status of confiscated animals destined for reintroduction is critical to assess whether these animals act as microorganism carriers and to investigate the epidemiology of transmissible diseases, a crucial aspect for animal and human health preservation. This study examined the occurrence of aerobic and facultative anaerobic bacteria and fungi in cloacal swabs collected from wild confiscated passerines intended for reintroduction programs. In vitro susceptibility tests of the most frequent isolates as well as studies of the molecular aspects of Escherichia coli isolates were also performed. There was microorganism growth in 62.5% of 253 samples. The microorganisms that were most frequently isolated were Staphylococcus spp. (15.0%), Micrococcus spp. (11.5%), E. coli (10.7%) and Klebsiella spp. (10.7%). Fifteen bacteria genera and seven fungi genera were isolated. Multidrug-resistance to antimicrobials was observed in Staphylococcus spp., Micrococcus spp., E. coli and Klebsiella spp. isolates. The high occurrence of Enterobacteria observed is possibly related to the sanitary conditions in which confiscated animals are usually kept. One E. coli sample (out of 27 isolates) was positive for the S-fimbrial adhesion encoding gene (sfa). Considering the low occurrence of genes that encode virulence factors, confiscated passerines may represent a low risk for the potential transmission of EPEC, APEC, UPEC and NMEC isolates to other animals or humans. The potential risk of intra- or inter-specific transmission of multidrug-resistant isolates and the introduction of these microorganisms into the environment must be considered, although there are still therapeutic alternatives for treatment of these animals among the antimicrobials which were tested. The stress and poor hygiene conditions imposed on animals during trafficking may have caused their contamination by multidrug-resistant agents transmitted by humans or by the precarious environment to which they were subjected. Risks related to the dissemination of Salmonella spp., Cryptococcus spp. and Candida spp. are low when reintroduction programs are considered.