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Salmonellosis is a disease caused by a bacterium Salmonella, a gram negative bacilli found in many environments, responsible for significant economic losses in poultry, and of great impact on public health. Among more than 2500 serovars, S. Heidelberg seems to be more invasive causing disease of greater severity than other serovars. The objective of this study was to investigate, through real-time PCR (qPCR), differences in the expression of a virulent gene (invA) and an antibiotic resistance gene (blaCTXM-2) of S. Heidelberg isolated from poultry meat (slaughterhouses) and drag swabs (field). Even though all isolates showed the presence of the invA gene, there were differences in the expression among the isolates, where isolates from the field showed greater expression of invA compared to samples isolated from meat products. On the other hand, isolates from the slaughterhouses showed greater expression of the blaCTX-M2 than those isolated from field samples.

Objetivou-se avaliar a qualidade do leite da região Oeste de Santa Catarina através da contagem bacteriana total, contagem de células somáticas e da quantificação de parâmetros físicoquímicos relacionados com as exigências da legislação brasileira (MAPA - Instrução Normativa nº 62/2011), ao longo dos anos de 2009 e 2010. Os parâmetros de qualidade avaliados foram gordura, proteína, lactose, sólidos não gordurosos, índice crioscópico, contagem bacteriana total (CBT) e contagem de células somáticas (CCS). Os resultados indicaram variações entre os anos, sendo que os teores de proteína, lactose e sólidos não gordurosos mantiveram-se superiores na maior parte de 2010, ao contrário do observado para o índice crioscópico. A CBT ficou acima do valor máximo permitido pela legislação em todo o período avaliado, com valores mais elevados no outono de ambos os anos avaliados. A CCS foi elevada e acima do padrão, na maioria dos meses de 2010. Além disso, foram observadas variações relativas nos períodos sazonais, com picos na CCS no verão de 2009 e 2010. O aumento observado nos níveis físico-químicos entre os anos de 2009 e 2010 pode estar relacionado ao pagamento de bônus pela qualidade do leite, que tem sido amplamente aplicado pela indústria laticinista para os produtores da região. Altas CCS e CBT indicam problemas na saúde dos rebanhos e de higiene no manejo e na ordenha, além de interferir na qualidade do leite e dos produtos lácteos.

Made available in DSpace on 2019-10-06T15:18:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-10 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The objective of this study was to verify the presence of antimicrobial resistant strains of Escherichia coli in pig farms and to use it as a biomarker to evaluate phenotypic and genotypic profiles of antimicrobial susceptibility, as well as the presence of Extended Spectrum Beta-lactamases (ESBLs) and fluoroquinolone resistance genes. Several samples (n = 306) collected from swine farms (n = 100) of Southern Brazil were used for E. coli isolation: 103 of swine feces, 105 of water, and 98 of soil. E. coli isolates were submitted to the disk-diffusion test to verify their antimicrobial susceptibility, to disk-approximation test to detect ESBL-producers, and to PCR analysis to search for ESBLs genes (blaCTY-M2, blaSHV-1, blaTEM-1, blaCTX-M2, blaOXA-1, blaPSE-1) and quinolone resistance genes (qnrA, qnrB and qnrS). The percentage of E. coli isolates found in feces, water and soil samples was 66.02%, 30.48% and 35.71%, respectively. The highest percentages of resistance were obtained for sulfamethoxazole associated with trimethoprim (63.70%), colistin (45.19%) and enrofloxacin (39.26%). Regarding the levels of multidrug resistance, 37.04% of the isolates were resistant to three or more classes of antimicrobials. The most common profile (16%) of multirresistance was GEM-SUT-ENO-COL. The index of multiple resistance to antimicrobials (IRMA) was above 0.2 in 78% of the multiresistant isolates. Out of 135 E. coli isolates, 7.41% was ESBL-producers, of which 50% showed the blaCMY-M2 gene, 40% the blaTEM-1 and 70% the qnrS gene. Of non-ESBL-producing strains resistant to enrofloxacin, 13.04% were positives for qnrS gene. These results demonstrated the presence of fecal contamination in the environment, in addition to high resistance indexes for several antimicrobials, including beta-lactams and fluoroquinolones, which was confirmed by the genetic detection of ESBLs and qnr genes. Post Graduation Program in Animal Science State University of Santa Catarina (UDESC) Western Center of Education Graduate in Animal Science State University of Santa Catarina (UDESC) Western Center of Education Department of Animal Science State University of Santa Catarina (UDESC) Western Center of Education Department of Mathematics Paulista State University Júlio de Mesquita Filho (UNESP) Department of Mathematics Paulista State University Júlio de Mesquita Filho (UNESP)

Bacteria of the genus Salmonella may infect humans and domestic animals, causing a serious public health problem worldwide. Nowadays, Salmonella enterica serovar Heidelberg (SH) is among the top three serovars isolated from people with salmonellosis and it is present in the poultry production chain. Moreover, it seems to be more invasive than other serotypes that cause enteritis. The overall status of the antimicrobial resistant of Brazilian strains of SH is still unknow. The bacterium may use similar mechanisms of resistance to antibotics, as well as disinfectants such as the efflux system and enzymatic degradation of chemical compounds. Thus, the objective of this study was to identify the Minimal Inhibitory Concentration (MIC) for ceftiofur of SH isolated from different materials of poultry origin, as well as to verify the relation between antibiotic resistance and disinfectant resistance. In addition, the screening efflux system was performed, using ethidium bromide to determine the presence of this mechanism of resistance. MIC results indicated high levels of SH resistance to ceftiofur, indicating the need for alternative drugs to treat salmonellosis. The concentration of ceftiofur needed to eliminate SH resistant isolates were 32 times higher than the therapeutic dose. Regarding disinfectants, most of the disinfectants tested were efficient to eliminate SH, however one isolate was resistant to glutaraldehyde-quaternary ammonia. All isolates were negatives in the screening efflux system, which suggest a different mechanism of resistance. It is possible to conclude that SH shows a real threat to poultry production, and caution should be taken when choosing the right antibiotic and disinfectant against this serovar. Bactérias do gênero Salmonella podem infectar o homem e animais domésticos, causando sérios problemas de saúde pública no mundo todo. Hoje, a Salmonella enterica serovar Heidelberg (SH) está entre os três sorovares mais comumente isolados de pessoas com salmonelose, e presente na cadeia produtiva avícola. Além disso, SH parece ser mais invasiva que outros sorovares que causam enterite. O perfil geral de resistência aos antimicrobianos de cepas brasileiras de SH ainda é desconhecido. Esta bactéria parece usar mecanismos de resistência aos antibióticos similares aos usados para desinfetantes, tais como a bomba de efluxo e a degradação enzimática de compostos químicos. Por isso, o objetivo deste trabalho foi de identificar a Concentração Mínima Inibitória (CMI) para o ceftiofur de isolados de SH oriundas de produtos avícolas diversos, bem como de verificar a relação entre resistência a antibióticos e desinfetantes. Além disso, o sistema de bomba de efluxo foi realizado usando o brometo de etídio para determinar se esse era o mecanismo de resistência utilizado. Os resultados do MIC indicaram altos níveis de resistência para ceftiofur, demonstrando a necessidade de formas alternativas para o tratamento da salmonelose. Desinfetantes routineiramente utilizados pela indústria avícola foram eficientes no combate da SH, porém um isolado mostrou-se resistente ao desinfetante glutaraldeído associado à amônia quaternária. Todos os isolados foram negativos para o sistema de bomba de efluxo, sugerindo que há outro mecanismo de resistência envolvido. É possível concluir que os isolados brasileiros de SH representam uma ameaça para a avicultura, e cautela deveria ser tomada na hora da escolha do antibiótico e do desinfetante a ser utilizado contra este sorovar.

Background: The development of antimicrobial resistance in bacteria is a serious public health issue worldwide. Salmonella spp. is considered a leader cause of gastrointestinal disease in animals and humans, and poultry products have been reported as an important reservoir of the bacterium. S. Heidelberg became lately one of the most prevalent serovars found in several countries. However, hardly any information is available about the epidemiology and the resistance profile of it. Therefore, the objective of this study was to determine the antibiotic resistance profile of S. Heidelberg (SH) and to compare to S. Enteritidis (SE) and S. Typhimurium (ST) isolated from the Southern part of Brazil.Materials, Methods & Results: A total of 162 Salmonella isolates of poultry origin serotyped as SH (54), SE (54), and ST (54) were submitted to the disk-diffusion test with disks containing 10 antibiotics of 7 different classes, routinely used in veterinary and human medicine such as: enrofloxacin, ciprofloxacin, norfloxacin, gentamicin, ceftiofur, ceftriaxone, nalidixic acid, tetracycline, sulfamethoxazole-trimethoprim, and chloramphenicol. In addition, the Multi-drug Resistance Pattern (MDRP) and the Multiple-Drug Resistance Index (MDRI) were determined. The Chi-square (χ2) test with 1% of significance level was used to statistically evaluate the results. All isolates were susceptible to norfloxacin, enrofloxacin, and ciprofloxacin. The majority of the isolates were resistant to the quinolone class (68%), more specifically to nalidixic acid, which is considered a synthetic quinolone, followed by penicillin (47%) and cephalosporin (16%). Overall, SH isolates showed higher resistance compared to ST and SE (18, 16.5, and 9.6%, respectively). SH isolated from field samples, mainly drag swabs, showed higher resistance levels (24.2%) than those isolated from slaughterhouses (5.6%). SH showed the highest percentage of resistance to ceftiofur (31.5%), ceftriaxone (9.3%), and tetracycline (64.8%) in comparison to the other two serotypes. Most of the SH isolates were resistant to at least two (66.7%), three or more antibiotics (33.3%). A different scenario was observed for ST and SE, where 25.9 and 9.3% were susceptible to at least one drug, respectively. The most common pattern of resistance (MDRP) was C (gentamicin - nalidixic acid - tetracycline) for 14 SH isolates, and A (ceftiofur - nalidixic acid - tetracycline) for 12 SH isolates. MDRI indicated that 22.8% of all isolates were multidrug resistant. SH was the isolate with the largest variety of resistance patterns compared to ST and SE, where 11.7% of the isolates were resistant to more than three antibiotics. In addition, SH showed the greatest MDRI (0.25) ranging from 0.2 to 0.5.Discussion: SH was resistant to almost all antibiotics tested and showed multi-drug resistant profile, therefores, it showed a potential for horizontal transmission of resistance genes. Additionally, SH showed a higher resistance profile for ceftiofur, an important antibiotic used in poultry, which can cross-resist to ceftriaxone, commonly used to treat salmonellosis in children. Our results showed that SH is a real challenge regarding antimicrobial resistance. This scenario leads to the need for rational and judicious use of antimicrobials in poultry and, as an alert to the medical community.