Avian pathogenic Escherichia coli (APEC) causes extraintestinal infections in birds, leading to an increase in the cost of poultry production. The ColV plasmid-linked genes iroN, ompT, hlyF, iss, and iutA have previously been suggested to be predictors of the virulence of APEC. In this research, we analyzed the frequencies of these genes in a Brazilian collection of E. coli isolated from birds with colibacillosis (APEC) and from apparently healthy birds (avian fecal [A(fecal)]), as well as from the litter of poultry houses of apparently healthy flocks (avian litter [A(litter)]). All the isolates that harbored ompT also harbored hlyF, so they were considered as one trait for statistical analysis. The relationship between in vivo virulence in 1-day-old chicks, expressed as a pathogenicity score, and the number of genes in each isolate showed that isolates with less than two of the four genes were rarely pathogenic, while most pathogenic isolates contained two or more genes. Nevertheless, about half of the nonpathogenic isolates also harbored two or more genes, in agreement with previous observations that commensal E. coli isolates from the birds' microbiota can serve as a reservoir of virulence genes. Thus, the pentaplex polymerase chain reaction can be used to indicate that a strain carrying none or only one gene would be nonpathogenic, but it cannot be used to indicate that a strain with two to four genes would be an APEC. Isolates allocated to phylogenetic group B2, which is frequently associated with extraintestinal infections, had the highest pathogenicity scores, while isolates allocated to group B1 had the lowest.

The environment, human, and animals play an important role in the spread of antibiotic-resistant bacteria. Enterococci are members of the gastrointestinal tracts of humans and animals and represent important reservoirs of antibiotic resistance genes. Until today, few studies have examined antibiotic susceptibility in enterococci isolated from primates. Therefore, the present study investigated species distribution, antibiotic susceptibility, and resistance genes in enterococci isolated from wild and captive black capuchins monkeys (Sapajus nigritus) in Rio Grande do Sul, South Brazil. A total of 24 swabs/fecal samples were collected, including 19 from wild monkeys living in two forest fragments [São Sebastião do Caí (SSC) and Santa Cruz do Sul (SCS)], and five in captive [Parque Zoológico da Fundação Zoobotânica (ZOO)], between August 2016 and November 2017. Fifteen colonies were randomly selected from each sample. Enterococci were identified by MALDI-TOF, tested for susceptibility to 12 antibiotics; and screened for tet(S), tet(M), tet(L), msrC, and erm(B) genes by PCR. Two-hundred ninety-six enterococci were isolated (SSC n = 137; SCS n = 86; ZOO n = 73) and differences in Enterococcus species distribution were detected on three monkey groups, with low abundance in SCS (1 - D = 0.2), followed by ZOO (1 - D = 0.68), and SSC (1 - D = 0.73). The enterococci frequently recovered include the following: Enterococcus faecalis (42.6%), E. hirae (29.1%), and E. faecium (15.9%). Antibiotic-nonsusceptible was observed in 202 (67.9%) strains. The rate of non-susceptibility to rifampicin, tetracycline, erythromycin, nitrofurantoin, chloramphenicol, and ampicillin was 46%, 26%, 22% and 19%, 13%, 0.3%, and 0.3%, respectively. All strains were susceptible to vancomycin, streptomycin, gentamycin, and linezolid. Forty-three (14.52%) isolates were identified as multidrug resistant (MDR), and the highest number of MDR enterococci were E. faecium recovered from wild monkeys living close to a hospital and water treatment plant. Elevated rates of antibiotic resistance genes msrC and tet(L) were isolates from ZOO. In conclusion, differences in the frequency of enterococci species, antibiotic-nonsusceptible and antibiotic resistance genes in all groups of monkeys were identified. These data suggest that anthropogenic activities could have an impact in the resistome of primate gut enterococci communities.

This study discussed the use of antimicrobials in the commercial chicken production system and the possible factors influencing the presence of Extended-spectrum β-lactamase (ESBL)/AmpC producers strains in the broiler production chain. The aim of this study was to perform longitudinal monitoring of ESBL-producing and fosfomycin-resistant Escherichia coli from poultry farms in southern Brazil (Paraná and Rio Grande do Sul states) and determine the possible critical points that may be reservoirs for these strains. Samples of poultry litter, cloacal swabs, poultry feed, water, and beetles (Alphitobius sp.) were collected during three distinct samplings. Phenotypic and genotypic tests were performed for characterization of antimicrobial resistant strains. A total of 117 strains were isolated and 78 (66%) were positive for ESBL production. The poultry litter presented ESBL positive strains in all three sampled periods, whereas the cloacal swab presented positive strains only from the second period. The poultry litter represents a significant risk factor mainly at the beginning poultry production (odds ratio 6.43, 95% confidence interval 1–41.21, p < 0.05). All beetles presented ESBL positive strains. The predominant gene was blaCTX–M group 2, which occurred in approximately 55% of the ESBL-producing E. coli. The cit gene was found in approximately 13% of the ESBL-producing E. coli as AmpC type determinants. A total of 19 out of 26 fosfomycin-resistant strains showed the fosA3 gene, all of which produced ESBL. The correlation between fosA3 and blaCTX–M group 1 (blaCTX–M55) genes was significant among ESBL-producing E. coli isolated from Paraná (OR 3.66, 95% CI 1.9–9.68) and these genetic determinants can be transmitted by conjugation to broiler chicken microbiota strains. Our data revealed that poultry litter and beetles were critical points during poultry production and the presence of fosfomycin-resistant strains indicate the possibility of risks associated with the use of this antimicrobial during production. Furthermore, the genetic determinants encoding CTX-M and fosA3 enzymes can be transferred to E. coli strains from broiler chicken microbiota, thereby creating a risk to public health.

The study aimed to evaluate the antimicrobial susceptibility of 109 samples of Escherichia coli (E. coli) of environmental origin and to characterize these isolates according to the degree of pathogenicity in vivo, verifying a possible relationship between this variable and susceptibility to the active principles tested. The isolates were subjected to disc diffusion test to 14 antibiotics. From 16.5% to 90% of the samples were sensitive; 1 - 28.5% showed intermediate degree of susceptibility and between 9 to 78% of E. coli analyzed were resistant. The highest resistance percentages were seen in the class of quinolones and tetracyclines (>75%), and for sensitivity in the class of amphenicols (68.8%). By inoculating 1- day - old chicks, the isolates were classified as highly pathogenic (2.7%), intermediate (10.1%), low (42.2%) and apathogenic (45%). It was observed a wide variation in the susceptibility profile of isolates in relation to antimicrobials. It was also found that most of the samples had pathogenic potential (55%), thus being considered as APEC (avian pathogenic E. coli). No relationship between pathogenicity and antimicrobial susceptibility (P≤0.05) was observed.

The aim of present study is to characterize the resistance and virulence profile of enterococci isolated from aquaculture excavated ponds and masonry tanks (6 samples) in southern Brazil. Samples were cultured in selective medium, 10 colonies were randomly selected from each sample, which were identified by MALDI-TOF and tested against 13 antimicrobials. The presence of resistance (tetL, tetM, tetS, ermB and msrC) and virulence (ace, esp, agg, cylA and gelE) genes were determined by PCR. A total of 79 enterococci were identified, and Entecococcus faecalis (44.3%) and E. casseliflavus (36.7%) were the most prevalent species isolated. Sixty-five strains (82.3%) were resistant to at least one of the antimicrobials tested, whereas 27 (34.2%) strains were multiresistant. The overall percentages of antimicrobial resistant isolates were: 58.2% to rifampicin, 40.5% to fluoroquinolones, 36.7% to erythromycin and 30.4% to tetracycline. The tetL and tetM genes were found in 57.7% of the tetracycline-resistant strains; and msrC in 31.01% of erythromycin-resistant strains. The most frequently detected virulence factors were ace and gelE genes. Although limited to a single farm, these data suggest that aquaculture may be a reservoir of resistant and virulent enterococci. This study is the first step towards enhancing our understandingof distribution, resistance and virulence profile in enterococci isolated from fish farming environments in the south Brazil.

Diarrheagenic (DEC) and avian pathogenic Escherichia coli (APEC) are associated with intestinal and extra-intestinal infections (ExPEC), respectively. We aimed to analyze the antimicrobial susceptibility, gene encoding virulence factors associated to DEC and APEC, and phylogenetic classification in E. coli isolated from 320 samples of feed and ingredients. Antimicrobial susceptibility was performed using the disk diffusion method and Multiple Antibiotic Resistance (MAR) Index and Multi-Drug Resistance (MDR) were calculated. Phylogenetic classification was performed on samples harboring DEC and/or APEC virulence-associated genes. A total of 110 E. coli strains were isolated in 15% (49/320) of the evaluated inputs (n=13 vegetable meal; n=33 animal meal, n=3 feed). In general, the isolates showed the highest rates of antimicrobial resistance to sulfonamide and cefazolin and 18% (20/110) were multi-drug resistant. MAR index of feed samples was the highest (0.467). Six and five strains had APEC and DEC virulence-associated genes, respectively, and belonging to phylogenetic groups A and B1. These findings point to the need for strict microbiological control during the production process of these foods.

No abstract

RESUMO.-[Primeira análise filogenética de Avipoxvirus (APV) no Brasil.] Este trabalho representa a primeira aná-lise filogenética de Poxvirus aviário detectado em perus no Brasil. Os distúrbios clínicos relacionados com bouba aviá-ria aqui descritos ocorreram em um sistema de alojamento de perus. As aves apresentaram lesões características de varíola observadas no pescoço, pálpebras e bico das aves. Quatro perus com sinais característicos foram escolhidos aleatoriamente, sacrificados e submetidos à autópsia. This study represents the first phylogenetic analysis of avian poxvirus recovered from turkeys in Brazil. The clinical disorders related to fowlpox herein described occurred in a turkey housing system. The birds displaying characteristic pox lesions which were observed on the neck, eyelids and beak of the turkeys. Four affected turkeys were randomly chosen, euthanized and necropsied. Tissues samples were submitted for histopathological analysis and total DNA was further extracted, amplified by conventional PCR, sequenced and phylogenetically analyzed. Avian poxviruses specific PCR was performed based on P4b core protein gene sequence. The histological analysis revealed dermal inflammatory process, granulation tissue, hyperplasia of epithelial cells and inclusion bodies. The P4b gene was detected in all samples. Sequencing revealed a 100% nucleotide and amino acid sequence identity among the samples, and the sequences were deposited in GenBank ® . The four Avian poxviruses fragments sequenced in this study clustered along the A1 clade of avipoxviruses, and were classified as Avipoxvirus (APV). Additional studies, such as virus isolation, PCR and sequencing includinga large number of specimens from the Brazilian turkey production must be conducted due to the hazardous risk that poxvirus infections may cause to the Brazilian poultry production scenario, given that Brazil's turkey production attracts attention due to its economic importance worldwide. Our findings point to the need to identify the prevalence of APV in Brazilian turkey production, to perform risk assessment studies and continued surveillance of APV infections in both wild and commercial avian species. . Estudos adicionais, como isolamento viral, PCR e sequenciamento, incluindo um grande número de perus da produção brasileira devem ser conduzidos devido ao grave risco que a infecção por poxvírus pode causar ao cenário de produção avícola brasileira, tendo em vista que a produção brasileira de perus atrai atenção devido a sua importância mundial. Nossos resultados apontam para a necessidade de identificar a prevalência da APV na produção de peru no Brasil, para realizar estudos de avaliação de risco e continuada monitoração de infecções por APV nas espécies de aves comerciais e silvestres.