CTX-M-producing Escherichia coli Isolated from urban pigeons (Columba livia domestica) in Brazil.

INTRODUCTION: Worldwide urban pigeons (Columba livia domestica) are an important reservoir of pathogenic and multidrug-resistant bacteria (MDR). Plasmids are key genetic elements in the dissemination of antimicrobial drug resistance in bacteria, including beta-lactams and quinolones, which are the most important classes of drugs for treatment of Enterobacteriaceae infections in human and veterinary medicine. The aim of this study was to determine the presence of Escherichia coli (E. coli) harboring plasmids containing extend-spectrum (ESBL) and pAmpC beta-lactamases, also plasmid-mediated quinolone resistance (PMQR) genes in urban pigeons from São Paulo State, Brazil. METHODOLOGY: A collection of 107 isolates of E. coli from urban pigeons from four cities was screened by antimicrobial resistance phenotypic and PCR for genes encoding ESBL, pAmpC and PMQR genes. Clonality was evaluated by ERIC-PCR. RESULTS: We found three strains positive for blaCTX-M genes. In two clonally related CTX-M-8-producing strains, the gene was associated with IncI1 plasmids. An MDR strain harboring blaCTX-M-2, the plasmid could not be transferred. No strain was positive for PMQR genes. CONCLUSION: These results indicate that CTX-M-2 and CTX-M-8-producing E. coli are present in urban pigeons, which could serve as a reservoir for ESBL-producing E. coli in Brazil.

Arcobacter spp. in fecal samples from Brazilian farmed caimans (Caiman yacare, Daudin 1802).

The aim of this study was to perform the identification and molecular characterization of Arcobacter cryaerophilus and Arcobacter butzleri isolated from caiman (Caiman yacare), kept at a production farm, in Brazil. Forty fecal samples were analyzed. After isolation and identification, 21/40 strains of A. butzleri and 19/40 strains of A. cryaerophilus were subjected to PCR for potential virulence gene detection. The results of the PCR showed 38/40 strains positive for the cadF, cj1349, ciaB, and tlyA genes, 39/40 strains positive for the pldA gene, and 40/40 strains positive for the mviN gene. None of the strains presented the irgA gene. Hemagglutinin (hecA gene) and hemolysin (hecB) genes were detected in 21/40 and 16/40 strains, respectively. The SE-AFLP showed a great genetic diversity, but some clonally groups were disseminated in various tanks. These data reveal that the strains presented the same virulence traits described from Arcobacter isolated from food-borne disease in humans.

High-virulence CMY-2- and CTX-M-2-producing avian pathogenic Escherichia coli strains isolated from commercial turkeys.

This study reports the high-virulence phylogenetic backgrounds of CMY-2- and CTX-M-2-producing avian pathogenic Escherichia coli strains isolated from turkeys sent to slaughter and condemned by airsacculitis in Brazil. Among 300 air sac samples, seven E. coli strains produced plasmid-mediated CMY-2-type AmpC, of which three carried also the blaCTX-M-2 Extended Spectrum Beta-Lactamase encoding gene. Interestingly, the transfer of the blaCMY-2 gene was positive for three E. coli strains, being associated with the presence of IncI1 plasmids. The complete sequence of the representative pJB10 plasmid revealed that the blaCMY-2 gene was within a transposon-like element in the classical genetic environment consisting of tnpA-blaCMY-2-blc-sugE structure. This plasmid with 94-kb belonged to the sequence type (ST) 12 among IncI1 plasmids, which has been associated with the worldwide spread of blaCMY-2 among Salmonella enterica and E. coli. Furthermore, to the best of our knowledge, this is the first complete sequence of a CMY-2-encoding plasmid derived from an Escherichia coli isolated from food-producing animals in Latin America.

Prebiotic effects of inulin extracted from burdock (Arctium lappa) in broilers / Efeito prebiótico da inulina extraída da bardana (Arctium lappa) em frangos de corte

The aim of this study was to evaluate the prebiotic effect of burdock (Arctium lappa) in commercial poultry. Four experiments were conducted to evaluate the performance parameters and the protection after challenge with Salmonella Enteritidis and Salmonella Kedougou, with and without Bifidobacterium probiotic. In two trials, the chickens were fed with flour burdock 1% during 42 days. In the other two, the chickens were fed with fructan extracted from burdock (inulin), by gavage, at a concentration of 100 mg/bird, during the first three days of life. The results showed that the broilers treated with burdock flour showed underperformed, with less weight gain from the second week, and the worst results in the fattening stage. The treated birds had diarrhea and impaired intestinal integrity. However, the groups treated with the flour had a lower rate of intestinal colonization by Salmonella Kedougou, after challenge. No statistically significant differences were detected in the performance parameters of broilers receiving the inulin, and the morphometric analysis showed no lesions in the intestinal villi. However, there was no protection in the challenge with Salmonella Enteritidis, regardless of association with probiotic. These results demonstrated that the manner of administration has influence on the prebiotic effect of burdock. The burdock flour was administered for 42 days, which may have influenced intestinal mucosal injury. Instead, the inulin was given only in the first three days, which may have been insufficient for protection against Salmonella. New experiments are needed to determine an able formulation for a protective effect, without negative impact on growth, weight gain and feed conversion of the supplemented animals.(AU)

Este projeto teve por objetivo avaliar o efeito prebiótico da bardana (Arctium lappa) em aves comerciais. Foram realizados quatro experimentos para avaliar os parâmetros zootécnicos e o grau de proteção após o desafio com Salmonella Kedougou e Salmonella Enteritidis, com e sem a adição de probióticos à base de Bifidobacterium. Em dois experimentos, as aves receberam a farinha de bardana 1% na ração, durante 42 dias. Nos outros dois, as aves receberam o frutano extraído da bardana (inulina), por gavagem, na concentração de 100 mg/ave, nos três primeiros dias de vida. Os resultados demonstraram que os frangos tratados com farinha de bardana apresentaram desempenho zootécnico inferior ao controle, com menor ganho de peso a partir da segunda semana e piores resultados na fase de engorda. As aves tratadas apresentaram diarreia e comprometimento da integridade intestinal. Em contrapartida, os grupos tratados com a farinha tiveram menor taxa de colonização intestinal por Salmonella Kedougou, após o desafio. Não foram detectadas diferenças estatisticamente significativas nos parâmetros zootécnicos dos frangos que receberam a inulina, e a análise morfométrica não evidenciou lesões nas vilosidades intestinais. No entanto, não houve proteção no desafio por Salmonella Enteritidis, independentemente da associação com probiótico. Esses resultados demonstraram que o modo de administração tem influência sobre o efeito prebiótico da bardana. A farinha de bardana foi administrada por 42 dias, o que pode ter causado a lesão da mucosa intestinal. Em contrapartida, a inulina foi administrada apenas nos primeiros três primeiros dias, o que pode ter sido insuficiente para proteção contra Salmonella. Novos experimentos são necessários para determinar uma formulação capaz de promover efeito protetor, sem impacto negativo no crescimento, ganho de peso e conversão alimentar dos animais suplementados.(AU)

Virulence profiles, phylogenetic background, and antibiotic resistance of Escherichia coli isolated from turkeys with airsacculitis.

Avian Pathogenic Escherichia coli (APEC) has been studied for decades because of its economic impact on the poultry industry. Recently, the zoonotic potential of APEC and multidrug-resistant strains have emerged. The aim of this study was to characterize 225 APEC isolated from turkeys presenting airsacculitis. The results showed that 92% of strains presented a multidrug-resistance (MDR), and the highest levels of resistance were to sulfamethazine (94%) and tetracycline (83%). Half of these strains were classified in phylogenetic group B2, followed by B1 (28.6%), A (17.1%), and D (4.8%). The prevalence of virulence genes was as follows: salmochelin (iroN, 95%), increased serum survival (iss, 93%), colicin V (cvi/cva, 67%), aerobactin (iucD, 67%), temperature-sensitive haemagglutinin (tsh, 56%), iron-repressible protein (irp2, 51%), invasion brain endothelium (ibeA, 31%), vacuolating autotransporter toxin (vat, 24%), K1 antigen (neuS, 19%), enteroaggregative heat-stable cytotoxin (astA, 17%), and pilus associated with pyelonephritis (papC, 15%). These results demonstrate that the majority of the investigated strains belonged to group B2 and were MDR. These data suggest that turkeys may serve as a reservoir of pathogenic and multidrug-resistance strains, reinforcing the idea that poultry plays a role in the epidemiological chain of ExPEC.

Salmonella Agona em Perus (Meleagris gallopavo) de criações comerciais no Brasil / Salmonella Agona in Turkeys (Meleagris gallopavo) in commercial farms from Brazil

Salmonella spp. é um dos principais agentes envolvidos em casos de doenças de origem alimentar em humanos, responsável por perdas significativas na avicultura. O presente trabalho investigou a presença de Salmonella spp. em fezes de perus comerciais no Brasil. Foram colhidos suabes fecais de 14 lotes de perus comerciais (pool de seis aves/lote). Os suabes foram submetidos aos procedimentos de isolamento bacteriológico convencionais e a detecção de DNA do agente foi realizada com a técnica de PCR. Salmonella spp. foi detectada em um total de nove lotes dos 14 avaliados. As amostras foram negativas na identificação molecular dos sorovares Enteritidis e Typhimurium. Os isolados foram encaminhados ao laboratório de referência para sorotipagem e identificados como S. Agona; um patógeno considerado emergente em vários países.

Abstract Salmonella spp. is one of the major players involved in cases of foodborne diseases in humans and is responsible for significant losses in the poultry industry. The aim of this study was to investigate the presence of Salmonella spp. in feces of commercial turkeys from Brazil. Fecal swabs from 14 turkey farms (pool of six poults/flocks) were collected. The swabs were subject to the conventional bacteriological isolation procedures and to DNA detection of the agent trough PCR. Salmonella spp. was present in a total of nine from 14 turkey farms evaluated. The samples were negative on molecular identification for serovars Enteritidis and Typhimurium. Isolated strains submitted to the reference laboratory for serotyping were identified as S. Agona that has been described as emergent pathogen in several countries.