Exploring bacterial diversity and antimicrobial resistance gene on a southern Brazilian swine farm.

The bacterial composition of and the circulation of antimicrobial resistance genes (ARGs) in waste from Brazilian swine farms are still poorly understood. Considering that antimicrobial resistance (AMR) is one of the main threats to human, animal, and environmental health, the need to accurately assess the load of ARGs released into the environment is urgent. Therefore, this study aimed to characterize the microbiota in a swine farm in southern Brazil and the resistome in swine farm wastewater treated in a series of waste stabilization ponds (WSPs). Samples were collected from farm facilities and the surrounding environment, representing all levels of swine manure within the treatment system. Total metagenomic sequencing was performed on samples from WSPs, and 16S-rDNA sequencing was performed on all the collected samples. The results showed increased bacterial diversity in WSPs, characterized by the presence of Caldatribacteriota, Cloacimonadota, Desulfobacterota, Spirochaetota, Synergistota, and Verrucomicrobiota. Furthermore, resistance genes to tetracyclines, lincosamides, macrolides, rifamycin, phenicol, and genes conferring multidrug resistance were detected in WSPs samples. Interestingly, the most abundant ARG was linG, which confers resistance to the lincosamides. Notably, genes conferring macrolide (mphG and mefC) and rifamycin (rpoB_RIF) resistance appeared in greater numbers in the late WSPs. These drugs are among the high-priority antibiotic classes for human health. Moreover, certain mobile genetic elements (MGEs) were identified in the samples, notably tnpA, which was found in high abundance. These elements are of particular concern due to their potential to facilitate the dissemination of ARGs among bacteria. In summary, the results indicate that, in the studied farm, the swine manure treatment system could not eliminate ARGs and MGEs. Our results validate concerns about Brazil's swine production system. The misuse and overuse of antimicrobials during animal production must be avoided to mitigate AMR.

Multidrug Efflux System-mediated resistance in Staphylococcus aureus under a One Health approach.

The aim of the study was to track the spread of antimicrobial resistance among the different sectors of One Health through the detection of Multidrug-Efflux-System in multidrug-resistant Staphylococcus aureus isolates. Multidrug-resistant (MDR) and methicillin-resistant (MRSA) S. aureus isolates were selected: 25 of human, one of animal and eight of food origin. The efflux system genes norA, norB, norC, LmrS, tet38 and msrA were screened by PCR. The activity of the efflux systems was determined by the minimum inhibitory concentration (MIC) of tetracycline and ciprofloxacin in the presence and absence of CCCP and in the quantification of ethidium bromide efflux. Furthermore, biofilm formation was determined in the presence and absence of the CCCP. The molecular epidemiology of the isolates was traced with the aid of PFGE. The gene norC was the most prevalent, detected in all isolates and msrA was the least prevalent, detected in only two isolates from humans. There was no difference in the MICs of tetracycline and ciprofloxacin in the presence of CCCP, but 55.9% of isolates showed ethidium bromide efflux. The presence of CCCP decreased the biofilm formation. Regarding the molecular epidemiology, in three clusters was a mixture of the isolates from different origins. Therefore, S. aureus MDR with active multidrug efflux systems are circulating between One Health domains and it is necessary to consider strategies to decrease this circulation in order to prevent the dissemination of resistance mediated by MES.

Comparative genomic analysis of ovine and other host associated isolates of Staphylococcus aureus exhibit the important role of mobile genetic elements and virulence factors in host adaptation.

Staphylococcus aureus is the main etiological agent of mastitis in small ruminants worldwide. This disease has a difficult cure and possible relapse, leading to significant economic losses in production, milk quality and livestock. This study performed comparative genomic analyses between 73 S. aureus genomes from different hosts (human, bovine, pig and others). This work isolated and sequenced 12 of these genomes from ovine. This study contributes to the knowledge of genomic specialization and the role of specific genes in establishing infection in ovine mastitis-associated S. aureus. The genomes of S. aureus isolated from sheep maintained a higher representation when grouped with clonal complexes 130 and 133. The genomes showed high genetic similarity, the species pan-genome consisting of 4200 genes (central = 2008, accessory = 1559 and unique = 634). Among these, 277 unique genes were related to the genomes isolated from sheep, with 39.6 % as hypothetical proteins, 6.4 % as phages, 6.4 % as toxins, 2.9 % as transporters, and 44.7 % as related to other proteins. Furthermore, at the pathogen level, they showed 80 genes associated with virulence factors and 19 with antibiotic resistance shared in almost all isolates. Although S. aureus isolated from ovine showed susceptibility to antimicrobials in vitro, ten genes were predicted to be associated with antibiotic inactivation and efflux pump, suggesting resistance to gentamicin and penicillin. This work may contribute to identifying genes acquired by horizontal transfer and their role in host adaptation, virulence, bacterial resistance, and characterization of strains affecting ovine.

First report and whole-genome sequencing of Pseudochrobactrum saccharolyticum in Latin America.

The Brucellaceae family comprises microorganisms similar both phenotypically and genotypically, making it difficult to identify the etiological agent of these infections. This study reports the first isolation, identification, and characterization of Pseudochrobactrum saccharolyticum (strain 115) from Latin America. Strain 115 was isolated in 2007 from a bovine in Brazil and was initially classified as Brucella spp. by classical microbiological tests and bcsp31 PCR. The antimicrobial susceptibility of strain 115 was tested against drugs used to treat human brucellosis by minimal inhibitory concentration test. Subsequently, the whole genome of the strain was sequenced, assembled, and characterized. Phylogenetic trees built from 16S rRNA and recA gene sequences enabled the classification of strain 115 as Pseudochrobactrum spp. Phylogenomic analysis using Single Nucleotide Polymorphisms and Average Nucleotide Identity allowed the classification of the strain as P. saccharolyticum. Additionally, a Tetra Correlation Search identified one related genome from the same species, which was compared with strain 115 by analyzing genomic islands. This is the first identification and whole-genome sequence of P. saccharolyticum in Latin America and highlights a challenge in the diagnosis of bovine brucellosis, which could be solved by including the sequencing of 16S rRNA and recA genes in routine diagnostics.

Prototheca bovis in goats: Experimental mastitis and treatment with polypyrrole.

Prototheca bovis has been associated with several cases of mastitis in cattle but no record of intramammary infections has been reported in goats. This infection does not respond to available treatments and the disposal recommendation of affected animals cause great damage to the dairy industry. Alternatives for dealing with infections caused by Prototheca spp. are required worldwide. In vitro results suggest polypyrrole as promising molecule for combating this alga, because an algaecide effect was observed on tested Prototheca spp. isolates. Thus, this study evaluated goats as an experimental model for intramammary infection by P. bovis and a protocol for treating these animals with an intramammary polypyrrole solution. The possibility of P. bovis promoting an intramammary infection in goats was experimentally proven, demonstrating this species as an important model for studies involving algae mastitis. Furthermore, polypyrrole reduced the counts of Prototheca sp. in the analyzed samples, showing potential to fight this microorganism also in vivo. The results obtained in this study demonstrate the ability of P. bovis to colonize breast tissue in lactating goats and the highly soluble molecule of polypyrrole has potential use for the treatment of protothecosis.

Bacteriocin Producing Streptococcus agalactiae Strains Isolated from Bovine Mastitis in Brazil.

Antibiotic resistance is one of the biggest health challenges of our time. We are now facing a post-antibiotic era in which microbial infections, currently treatable, could become fatal. In this scenario, antimicrobial peptides such as bacteriocins represent an alternative solution to traditional antibiotics because they are produced by many organisms and can inhibit bacteria, fungi, and/or viruses. Herein, we assessed the antimicrobial activity and biotechnological potential of 54 Streptococcus agalactiae strains isolated from bovine mastitis. Deferred plate antagonism assays revealed an inhibition spectrum focused on species of the genus Streptococcus-namely, S. pyogenes, S. agalactiae, S. porcinus, and S. uberis. Three genomes were successfully sequenced, allowing for their taxonomic confirmation via a multilocus sequence analysis (MLSA). Virulence potential and antibiotic resistance assessments showed that strain LGMAI_St_08 is slightly more pathogenic than the others. Moreover, the mreA gene was identified in the three strains. This gene is associated with resistance against erythromycin, azithromycin, and spiramycin. Assessments for secondary metabolites and antimicrobial peptides detected the bacteriocin zoocin A. Finally, comparative genomics evidenced high similarity among the genomes, with more significant similarity between the LGMAI_St_11 and LGMAI_St_14 strains. Thus, the current study shows promising antimicrobial and biotechnological potential for the Streptococcus agalactiae strains.

Impact of polymorphisms in blaZ, blaR1 and blaI genes and their relationship with ß-lactam resistance in S. aureus strains isolated from bovine mastitis.

There is not a consensus between the presence of the genotypic resistance marker gene and the phenotypic resistance to ß-lactams in Staphylococcus aureus, which means, positive S. aureus blaZ isolates demonstrating sensitivity to ß-lactams. The present study aimed to characterize the blaZ, blaR1 and blaI genes, identify and evaluate single nucleotide polymorphisms (SNPs) and their relationship with ß-lactam resistance in samples of Staphylococcus aureus obtained from cases of bovine mastitis. Five isolates (two resistant and three sensitive to oxacillin) of Staphylococcus aureus with detected production of beta-lactamase, previously evaluated as containing the blaZ gene and negative for the mecA and mecC genes, had the bla operon completely sequenced. Impacts on the protein sequence due to the detected polymorphisms were evaluated by modeling the proteins encoded by the blaZ, blaR1 and blaI genes using a three-dimensional model structure obtained from the Protein Data Bank (PDB) database. Fifteen SNPs were detected in the blaZ gene, 30 in the blaR1 gene and three in the blaI gene. These SNPs caused alterations in amino acid sites. Deleterious mutations were detected in the blaZ gene (E146G, P218S, Y221C) and the blaR1 gene (K481E). Molecular docking analysis revealed that polymorphisms in the blaZ gene may explain the phenotypic sensitivity in isolates that contain the resistance marker gene. Although sensitive and resistant isolates encode beta-lactamase, these proteins are functionally altered due to a change in the binding site with the antibiotic.

Virulence Factors in Staphylococcus aureus and Quality of Raw Milk from Dairy Cows in a Semiarid Region of Northeastern Brazil

Background: Milk quality is considered unsatisfactory in Brazil due to factors of a social, economic, cultural, and climatic nature. Mastitis is the main disease that affects dairy herds. Microorganisms of the genus Staphylococcus are the most frequently isolated pathogens in cases of mastitis in bovines. Staphylococcus aureus requires more attention because they have the ability to develop resistance to antimicrobials used in the treatment of mastitis. Thus, the aim of the present study was to evaluate virulence factors in isolates of S. aureus as well as analyze the hygienic-sanitary quality of raw milk produced on dairy farms in a semiarid region of northeastern Brazil.Material, Methods & Results: Samples were taken from milk containers at 44 properties. Fifty-eight isolates of Staphylococcus spp. were analyzed and genotypically identified as S. aureus. In the phenotypic characterization, 56.8% (33/58) of the isolates demonstrated moderate biofilm production. In the genotypic characterization (icaA, icaD and bap genes), icaA was the most representative among the isolates. No resistance to cephalothin or oxacillin was found, but 62% (36/58) of the isolates exhibited resistance to ampicillin, amoxicillin, and penicillin. In the genotypic evaluation in response to -lactam antibiotics, 50% (29/58) of the isolates exhibited the blaZ gene. Total bacterial counts were determin

Virulence Factors in Staphylococcus aureus and Quality of Raw Milk from Dairy Cows in a Semiarid Region of Northeastern Brazil

Background: Milk quality is considered unsatisfactory in Brazil due to factors of a social, economic, cultural, and climatic nature. Mastitis is the main disease that affects dairy herds. Microorganisms of the genus Staphylococcus are the most frequently isolated pathogens in cases of mastitis in bovines. Staphylococcus aureus requires more attention because they have the ability to develop resistance to antimicrobials used in the treatment of mastitis. Thus, the aim of the present study was to evaluate virulence factors in isolates of S. aureus as well as analyze the hygienic-sanitary quality of raw milk produced on dairy farms in a semiarid region of northeastern Brazil.Material, Methods & Results: Samples were taken from milk containers at 44 properties. Fifty-eight isolates of Staphylococcus spp. were analyzed and genotypically identified as S. aureus. In the phenotypic characterization, 56.8% (33/58) of the isolates demonstrated moderate biofilm production. In the genotypic characterization (icaA, icaD and bap genes), icaA was the most representative among the isolates. No resistance to cephalothin or oxacillin was found, but 62% (36/58) of the isolates exhibited resistance to ampicillin, amoxicillin, and penicillin. In the genotypic evaluation in response to -lactam antibiotics, 50% (29/58) of the isolates exhibited the blaZ gene. Total bacterial counts were determin

Virulence Factors in Staphylococcus aureus and Quality of Raw Milk from Dairy Cows in a Semiarid Region of Northeastern Brazil

Background: Milk quality is considered unsatisfactory in Brazil due to factors of a social, economic, cultural, and climatic nature. Mastitis is the main disease that affects dairy herds. Microorganisms of the genus Staphylococcus are the most frequently isolated pathogens in cases of mastitis in bovines. Staphylococcus aureus requires more attention because they have the ability to develop resistance to antimicrobials used in the treatment of mastitis. Thus, the aim of the present study was to evaluate virulence factors in isolates of S. aureus as well as analyze the hygienic-sanitary quality of raw milk produced on dairy farms in a semiarid region of northeastern Brazil.Material, Methods & Results: Samples were taken from milk containers at 44 properties. Fifty-eight isolates of Staphylococcus spp. were analyzed and genotypically identified as S. aureus. In the phenotypic characterization, 56.8% (33/58) of the isolates demonstrated moderate biofilm production. In the genotypic characterization (icaA, icaD and bap genes), icaA was the most representative among the isolates. No resistance to cephalothin or oxacillin was found, but 62% (36/58) of the isolates exhibited resistance to ampicillin, amoxicillin, and penicillin. In the genotypic evaluation in response to -lactam antibiotics, 50% (29/58) of the isolates exhibited the blaZ gene. Total bacterial counts were determin

Virulence Factors in Staphylococcus aureus and Quality of Raw Milk from Dairy Cows in a Semiarid Region of Northeastern Brazil

Background: Milk quality is considered unsatisfactory in Brazil due to factors of a social, economic, cultural, and climatic nature. Mastitis is the main disease that affects dairy herds. Microorganisms of the genus Staphylococcus are the most frequently isolated pathogens in cases of mastitis in bovines. Staphylococcus aureus requires more attention because they have the ability to develop resistance to antimicrobials used in the treatment of mastitis. Thus, the aim of the present study was to evaluate virulence factors in isolates of S. aureus as well as analyze the hygienic-sanitary quality of raw milk produced on dairy farms in a semiarid region of northeastern Brazil.Material, Methods & Results: Samples were taken from milk containers at 44 properties. Fifty-eight isolates of Staphylococcus spp. were analyzed and genotypically identified as S. aureus. In the phenotypic characterization, 56.8% (33/58) of the isolates demonstrated moderate biofilm production. In the genotypic characterization (icaA, icaD and bap genes), icaA was the most representative among the isolates. No resistance to cephalothin or oxacillin was found, but 62% (36/58) of the isolates exhibited resistance to ampicillin, amoxicillin, and penicillin. In the genotypic evaluation in response to -lactam antibiotics, 50% (29/58) of the isolates exhibited the blaZ gene. Total bacterial counts were determin

Virulence Factors in Staphylococcus aureus and Quality of Raw Milk from Dairy Cows in a Semiarid Region of Northeastern Brazil

Background: Milk quality is considered unsatisfactory in Brazil due to factors of a social, economic, cultural, and climatic nature. Mastitis is the main disease that affects dairy herds. Microorganisms of the genus Staphylococcus are the most frequently isolated pathogens in cases of mastitis in bovines. Staphylococcus aureus requires more attention because they have the ability to develop resistance to antimicrobials used in the treatment of mastitis. Thus, the aim of the present study was to evaluate virulence factors in isolates of S. aureus as well as analyze the hygienic-sanitary quality of raw milk produced on dairy farms in a semiarid region of northeastern Brazil.Material, Methods & Results: Samples were taken from milk containers at 44 properties. Fifty-eight isolates of Staphylococcus spp. were analyzed and genotypically identified as S. aureus. In the phenotypic characterization, 56.8% (33/58) of the isolates demonstrated moderate biofilm production. In the genotypic characterization (icaA, icaD and bap genes), icaA was the most representative among the isolates. No resistance to cephalothin or oxacillin was found, but 62% (36/58) of the isolates exhibited resistance to ampicillin, amoxicillin, and penicillin. In the genotypic evaluation in response to -lactam antibiotics, 50% (29/58) of the isolates exhibited the blaZ gene. Total bacterial counts were determin

Aeromonas hydrophila in tilapia (Oreochromis niloticus) after the intake of aflatoxins

The objectives of this study were to assess the effect of the intake of aflatoxin on the development of tilapia and to evaluate the impact of inoculation with Aeromonas hydrophila on performance parameters, so these two individual tests were performed. One hundred and twenty fingerlings aged 35 days old, with mean weight of 1.55 ± 0.005 g and mean length of 5 cm were used in each test, distributed in 20 tanks. Each experimental unit consisted of a 60 L tank with six fingerlings. In the first experiment, increasing levels of aflatoxin (0.350, 0.757, 1.177 mg.kg feed-1) were used as treatments and, for the control group, a diet without aflatoxin was used in a completely randomized design with four treatments and five replicates. In the second experiment, a control group of Nile tilapia fingerlings was used and received a diet without aflatoxin, inoculated with saline solution (group 1) and Aeromonas hydrophila (group 2), as well as groups of animals fed on diets containing 0.350 mg.kg feed-1of aflatoxin (group 3), 0.757 mg.kg feed-1of aflatoxin (group 4) and 1.177 mg.kg feed-1of aflatoxin (group 5), and these groups were inoculated with Aeromonas hydrophila. The survival rate and the total length of fingerlings were influenced by the treatments (p 0.05). The synergistic action of aflatoxins and Aeromonas hydrophila was effective and caused the death of experimental fish, thus affecting feed conversion and length.

Os objetivos deste estudo foram analisar o consumo de aflatoxinas sobre o desenvolvimento de alevinos de tilápia e avaliar o efeito da inoculação de Aeromonas hydrophilasobre os parâmetros de desempenho produtivo dos animais. Para isso, dois testes individuais foram realizados. Foram utilizados 120 alevinos com 35 dias e 1,55 ± 0,005 g de peso médio em cada ensaio, distribuídos em 20 aquários. Cada unidade experimental foi constituída por um aquário de 60 L com seis alevinos. No primeiro ensaio, como tratamentos foram utilizados níveis crescentes de inclusão de aflatoxina (0,350; 0,757; 1,177 mg.kg ração-1) e um grupo controle com ração sem aflatoxina, em um delineamento inteiramente randomizado com quatro tratamentos e cinco repetições. No segundo ensaio, utilizou-se um grupo controle que recebeu ração livre de aflatoxina, o qual foi inoculado com solução salina (grupo 1) e Aeromonas hydrophila (grupo 2), bem como grupos de animais que receberam ração contendo 0,350 mg.kg feed-1 de aflatoxina (grupo 3); 0,757 mg.kg feed-1 de aflatoxina (grupo 4); e 1,177 mg.kg ração-1de aflatoxina (grupo 5), sendo estes grupos inoculados com Aeromonas hydrophila. A sobrevivência e o comprimento total dos alevinos foram influenciados pelos tratamentos (p 0,05). A ação sinérgica de aflatoxinas e Aeromonas hydrophila mostrou-se eficaz ao provocar a morte dos alevinos e influenciar a conversão alimentar e comprimento.

Phenotypic and molecular characterization of isolates of Staphylococcus spp. obtained from sheep milk Chapecó-SC / Caracterização fenotípica e molecular de isolados de Staphylococcus spp. obtidos de leite de ovelhas do Município de Chapecó-SC

This study aimed to determine the antimicrobial susceptibility profile and to assess the presence of mechanisms of antimicrobial resistance in Staphylococcus spp. (n=36) isolated from mastitis in sheeps Chapecó-SC. The potential for biofilm production was determined by phenotypic tests of Congo Red Agar, DAPI and Gentian Violet and by PCR for the detection of icaD gene. To evaluate the antimicrobial resistance testing was performed disk diffusion and detection of resistance genes blaZ, mecA, ermA, ermB and ermC and msrA also performed by PCR.The pump test was conducted by efuxo crop growth Muller Hinton agar containing ethidium bromide. The results showed that 1 (2,78%), 36 (100%) and 10 (27,78%) isolates were considered to produce a biofilm on Congo Red Agar test, Gentian Violet and DAPI, respectively, while the gene icaD was observed in only 2 (5.55%) isolates. The lowest percentage of sensitivity was observed for ampicillin (58.33%) and penicillin (58.33%). All strains tested were negative for the mecA, ermA, ermB and ermC genes. However, the isolates were positive for other resistance genes, being the blaZ and the msrA, with percentages of positivity of 58.33% and 11.11% respectively. Only one sample was positive for efflux pump test.

O presente trabalho teve como objetivos determinar o perfil de sensibilidade aos antimicrobianos e avaliar a presença de mecanismos de resistência antimicrobiana em Staphylococcus spp. (n=36) isolados de mastite em ovelhas do município de Chapecó-SC. O potencial para produção de biofilme foi determinado pelos testes fenotípicos de Agar Vermelho Congo, DAPI e Violeta de Genciana e por teste molecular pela técnica de PCR para a detecção do gene icaD. Para determinar o perfil de resistência aos antimicrobianos, foi realizado o teste de difusão em disco e detecção dos genes de resistência blaZ, mecA, erm (A, B e C) e msrA. O teste da bomba de efuxo foi realizado através do crescimento das culturas em Agar Muller Hinton contendo brometo de etídio. Os resultados mostraram que 1 (2,78%), 36 (100%) e 10 (27,78%) isolados foram considerados produtores de biofilme pelos testes de Agar Vermelho Congo, DAPI e Violeta de Genciana, respectivamente, enquanto que o gene icaD foi observado em apenas 2 (5,55%) isolados. O menor percentual de sensibilidade foi observado para ampicilina (58,33%) e penicilina (58,33%). Os isolados avaliados foram positivos para os genes de resistência blaZ (58,33%) e msrA (11,11%). Nenhum isolado apresentou os genes de resistência erm (A, B, C) e apenas uma amostra foi positiva para o teste da bomba de efluxo.

Phenotypic and molecular characterization of isolates of Staphylococcus spp. obtained from sheep milk Chapecó-SC / Caracterização fenotípica e molecular de isolados de Staphylococcus spp. obtidos de leite de ovelhas do Município de Chapecó-SC

This study aimed to determine the antimicrobial susceptibility profile and to assess the presence of mechanisms of antimicrobial resistance in Staphylococcus spp. (n=36) isolated from mastitis in sheeps Chapecó-SC. The potential for biofilm production was determined by phenotypic tests of Congo Red Agar, DAPI and Gentian Violet and by PCR for the detection of icaD gene. To evaluate the antimicrobial resistance testing was performed disk diffusion and detection of resistance genes blaZ, mecA, ermA, ermB and ermC and msrA also performed by PCR.The pump test was conducted by efuxo crop growth Muller Hinton agar containing ethidium bromide. The results showed that 1 (2,78%), 36 (100%) and 10 (27,78%) isolates were considered to produce a biofilm on Congo Red Agar test, Gentian Violet and DAPI, respectively, while the gene icaD was observed in only 2 (5.55%) isolates. The lowest percentage of sensitivity was observed for ampicillin (58.33%) and penicillin (58.33%). All strains tested were negative for the mecA, ermA, ermB and ermC genes. However, the isolates were positive for other resistance genes, being the blaZ and the msrA, with percentages of positivity of 58.33% and 11.11% respectively. Only one sample was positive for efflux pump test.

O presente trabalho teve como objetivos determinar o perfil de sensibilidade aos antimicrobianos e avaliar a presença de mecanismos de resistência antimicrobiana em Staphylococcus spp. (n=36) isolados de mastite em ovelhas do município de Chapecó-SC. O potencial para produção de biofilme foi determinado pelos testes fenotípicos de Agar Vermelho Congo, DAPI e Violeta de Genciana e por teste molecular pela técnica de PCR para a detecção do gene icaD. Para determinar o perfil de resistência aos antimicrobianos, foi realizado o teste de difusão em disco e detecção dos genes de resistência blaZ, mecA, erm (A, B e C) e msrA. O teste da bomba de efuxo foi realizado através do crescimento das culturas em Agar Muller Hinton contendo brometo de etídio. Os resultados mostraram que 1 (2,78%), 36 (100%) e 10 (27,78%) isolados foram considerados produtores de biofilme pelos testes de Agar Vermelho Congo, DAPI e Violeta de Genciana, respectivamente, enquanto que o gene icaD foi observado em apenas 2 (5,55%) isolados. O menor percentual de sensibilidade foi observado para ampicilina (58,33%) e penicilina (58,33%). Os isolados avaliados foram positivos para os genes de resistência blaZ (58,33%) e msrA (11,11%). Nenhum isolado apresentou os genes de resistência erm (A, B, C) e apenas uma amostra foi positiva para o teste da bomba de efluxo. 

ANTIBACTERIAL EFFECT OF BRAZILIAN BROWN PROPOLIS IN DIFFERENT SOLVENTS AGAINST Staphylococcus spp. ISOLATED FROM CAPRINE MASTITIS / AÇÃO ANTIBACTERIANA DA PRÓPOLIS MARROM BRASILEIRA EM DIFERENTES SOLVENTES CONTRA Staphylococcus spp. ISOLADOS DE CASOS DE MASTITE CAPRINA

The purpose of the present study was to evaluate the antimicrobial activity of propolis extracts diluted in different solvents against bacteria from Staphylococcus genus. The study was performed in the Immunology and Microbiology Laboratory from Universidade Federal do Vale do São Francisco. The propolis extracts were prepared using brown propolis diluted in different solvents such as chloroform, methanol, ethyl acetate and grain alcohol. In order to determine the antimicrobial potential of extracts, agar well diffusion method was used, with controls for each diluent. After that, Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) methods were used. All tests were performed in triplicate. In the agar well diffusion test, the measurements of the inhibition zone for propolis extract were as follows:  grain alcohol and propolis (2.88mm), methanol and propolis (2.41mm), chloroform and propolis (2.40mm) and ethyl acetate and propolis (0.83mm). The MBC of propolis extracts in different solvents were 93.75 ?g/mL for grain alcohol, 375 ?g/mL for chloroform and methanol and 3,000 ?g/ml for ethyl acetate. Statistically significant differences were achieved comparing the inhibition zones of propolis diluted in grain alcohol and ethyl acetate (2.88 and 0.83 mm, respectively). Considering the low cost of therapy and the activity of the propolis against caprin

O objetivo deste trabalho foi estudar a ação antimicrobiana do extrato da própolis em diferentes diluentes sobre bactérias do gênero Staphylococcus. Os extratos foram preparados utilizando-se diferentes diluentes, sendo eles o álcool de cereais, clorofórmio, acetato de etila e metanol. Foi utilizado o método de difusão em ágar por meio de poço, sendo utilizados controles para cada diluente. Em seguida, foi empregada a técnica da Concentração Inibitória Mínima (MIC) e da Concentração Bactericida Mínima (CBM). Todos os ensaios foram realizados em triplicata. No método de difusão em ágar, utilizando-se poço, observaram-se as seguintes médias para o halo de inibição: álcool de cereais (2,88 mm), álcool metílico (2,41 mm), clorofórmio (2,40 mm) e acetato de etila (0,83 mm). Foram obtidas as seguintes médias nos testes da CBM: 93,75 µg/mL para o extrato com álcool de cereais, 375 µg/ml para o extrato com clorofórmio e com metanol e 3.000 µg/mL para o extrato com acetato de etila. Foram observadas diferenças estatísticas significativas entre as médias de halo de inibição para a própolis diluída em álcool de cereais e aquela diluída em acetato de etila (2,88 e 0,83 mm, respectivamente). Considerando o baixo custo dessa terapia e a atividade da propolis contra esses patógenos da mastite, estudos in vivo e a caracterização química devem ser realizados, além da determinação dos aspectos t

Molecular identification of Clostridium chauvoei from common filter paper / Molecular identification of Clostridium chauvoei from common filter paper

Background: Blackleg is an acute and often fatal infection in bovine caused by the bacterium Clostridium chauvoei. The absence of conclusive diagnosis of blackleg usually occurs due to absence of practical and economical methods to send samples to microbiology laboratory. The goal of this work was to verify the possibility of using ordinary fi lter paper as a practical and economically feasible method for collecting, storing and shipping material to the laboratory to be used in a rapid and direct PCR approach to detect Clostridium chauvoei DNA.Materials, Methods & Results: The PCR technique for the diagnosis of blackleg from common fi lter paper was tested for specifi city, sensitivity and feasibility. To test the specifi city, the papers were impregnated with a suspension of the following microorganisms: C. chauvoei, C. perfringens, C. septicum, Bacillus anthracis, Staphylococcus aureus, and Escherichia coli. To test the sensitivity different concentration of C. chauvoei (ATCC 10092) were pipetted on common fi lter paper. To both test, DNA extraction of impregnated ordinary fi lter paper and their respective controls followed the method previously described and tested under different storage times (0 h, 24 h, 72 h and a week later). To test the feasibility, 12 bovine livers were collected and tissues samples were impregnate on common fi lter paper with suspension of C. cha

Background: Blackleg is an acute and often fatal infection in bovine caused by the bacterium Clostridium chauvoei. The absence of conclusive diagnosis of blackleg usually occurs due to absence of practical and economical methods to send samples to microbiology laboratory. The goal of this work was to verify the possibility of using ordinary fi lter paper as a practical and economically feasible method for collecting, storing and shipping material to the laboratory to be used in a rapid and direct PCR approach to detect Clostridium chauvoei DNA.Materials, Methods & Results: The PCR technique for the diagnosis of blackleg from common fi lter paper was tested for specifi city, sensitivity and feasibility. To test the specifi city, the papers were impregnated with a suspension of the following microorganisms: C. chauvoei, C. perfringens, C. septicum, Bacillus anthracis, Staphylococcus aureus, and Escherichia coli. To test the sensitivity different concentration of C. chauvoei (ATCC 10092) were pipetted on common fi lter paper. To both test, DNA extraction of impregnated ordinary fi lter paper and their respective controls followed the method previously described and tested under different storage times (0 h, 24 h, 72 h and a week later). To test the feasibility, 12 bovine livers were collected and tissues samples were impregnate on common fi lter paper with suspension of C. cha

Antibacterial activity of essential oil of cinnamon and trans-cinnamaldehyde against Staphylococcus spp. Isolated from clinical mastitis of cattle and goats / Antibacterial activity of essential oil of cinnamon and trans-cinnamaldehyde against Staphylococcus spp. isolated from clinical mastitis of cattle and goats

Background: Milk production plays a role as a source of protein and constitutes an important socioeconomic factor for small farms. The lack of planning of the creators, together with the lack of specialized technical assistance, and the precarious hygienic and sanitary management, are barriers that hinder the development of the activity. Bovine and caprine mastitis is an infl ammation process of the mammary gland caused by microorganisms. Staphylococcus spp. is the main causative agent of mastitis, with higher prevalence in cases of clinical and subclinical manifestations. The most common treatment is based on intramammary infusion of antibacterial agents. However, cure rates obtained with such drugs are not always effectives, because it may determine the emergence of resistant bacteria as well increase amounts of antibiotic residues in milk. Nevertheless, the treatment of bovine subclinical mastitis caused by Staphylococcus spp. in the lactation can be economically unviable. Alternative treatments of bovine mastitis with plant derived compounds have been described. The investigation of its antimicrobial activity against bacterial agents of mastitis is justifi able.Materials, Methods & Results: This study evaluated the antimicrobial activity of essential oil (EO) of Cinnamomum zeylanicum (cinnamon) and the fraction trans-cinnamaldehyde (TC) against 65 isolates of Staphyloco

Background: Milk production plays a role as a source of protein and constitutes an important socioeconomic factor for small farms. The lack of planning of the creators, together with the lack of specialized technical assistance, and the precarious hygienic and sanitary management, are barriers that hinder the development of the activity. Bovine and caprine mastitis is an infl ammation process of the mammary gland caused by microorganisms. Staphylococcus spp. is the main causative agent of mastitis, with higher prevalence in cases of clinical and subclinical manifestations. The most common treatment is based on intramammary infusion of antibacterial agents. However, cure rates obtained with such drugs are not always effectives, because it may determine the emergence of resistant bacteria as well increase amounts of antibiotic residues in milk. Nevertheless, the treatment of bovine subclinical mastitis caused by Staphylococcus spp. in the lactation can be economically unviable. Alternative treatments of bovine mastitis with plant derived compounds have been described. The investigation of its antimicrobial activity against bacterial agents of mastitis is justifi able.Materials, Methods & Results: This study evaluated the antimicrobial activity of essential oil (EO) of Cinnamomum zeylanicum (cinnamon) and the fraction trans-cinnamaldehyde (TC) against 65 isolates of Staphyloco

ANTIBACTERIAL EFFECT OF BRAZILIAN BROWN PROPOLIS IN DIFFERENT SOLVENTS AGAINST Staphylococcus spp. ISOLATED FROM CAPRINE MASTITIS / AÇÃO ANTIBACTERIANA DA PRÓPOLIS MARROM BRASILEIRA EM DIFERENTES SOLVENTES CONTRA Staphylococcus spp. ISOLADOS DE CASOS DE MASTITE CAPRINA

The purpose of the present study was to evaluate the antimicrobial activity of propolis extracts diluted in different solvents against bacteria from Staphylococcus genus. The study was performed in the Immunology and Microbiology Laboratory from Universidade Federal do Vale do São Francisco. The propolis extracts were prepared using brown propolis diluted in different solvents such as chloroform, methanol, ethyl acetate and grain alcohol. In order to determine the antimicrobial potential of extracts, agar well diffusion method was used, with controls for each diluent. After that, Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) methods were used. All tests were performed in triplicate. In the agar well diffusion test, the measurements of the inhibition zone for propolis extract were as follows:  grain alcohol and propolis (2.88mm), methanol and propolis (2.41mm), chloroform and propolis (2.40mm) and ethyl acetate and propolis (0.83mm). The MBC of propolis extracts in different solvents were 93.75 ?g/mL for grain alcohol, 375 ?g/mL for chloroform and methanol and 3,000 ?g/ml for ethyl acetate. Statistically significant differences were achieved comparing the inhibition zones of propolis diluted in grain alcohol and ethyl acetate (2.88 and 0.83 mm, respectively). Considering the low cost of therapy and the activity of the propolis against caprin

O objetivo deste trabalho foi estudar a ação antimicrobiana do extrato da própolis em diferentes diluentes sobre bactérias do gênero Staphylococcus. Os extratos foram preparados utilizando-se diferentes diluentes, sendo eles o álcool de cereais, clorofórmio, acetato de etila e metanol. Foi utilizado o método de difusão em ágar por meio de poço, sendo utilizados controles para cada diluente. Em seguida, foi empregada a técnica da Concentração Inibitória Mínima (MIC) e da Concentração Bactericida Mínima (CBM). Todos os ensaios foram realizados em triplicata. No método de difusão em ágar, utilizando-se poço, observaram-se as seguintes médias para o halo de inibição: álcool de cereais (2,88 mm), álcool metílico (2,41 mm), clorofórmio (2,40 mm) e acetato de etila (0,83 mm). Foram obtidas as seguintes médias nos testes da CBM: 93,75 µg/mL para o extrato com álcool de cereais, 375 µg/ml para o extrato com clorofórmio e com metanol e 3.000 µg/mL para o extrato com acetato de etila. Foram observadas diferenças estatísticas significativas entre as médias de halo de inibição para a própolis diluída em álcool de cereais e aquela diluída em acetato de etila (2,88 e 0,83 mm, respectivamente). Considerando o baixo custo dessa terapia e a atividade da propolis contra esses patógenos da mastite, estudos in vivo e a caracterização química devem ser realizados, além da determinação dos aspectos t

Antibacterial activity of essential oil of cinnamon and trans-cinnamaldehyde against Staphylococcus spp. Isolated from clinical mastitis of cattle and goats / Antibacterial activity of essential oil of cinnamon and trans-cinnamaldehyde against Staphylococcus spp. isolated from clinical mastitis of cattle and goats

Background: Milk production plays a role as a source of protein and constitutes an important socioeconomic factor for small farms. The lack of planning of the creators, together with the lack of specialized technical assistance, and the precarious hygienic and sanitary management, are barriers that hinder the development of the activity. Bovine and caprine mastitis is an infl ammation process of the mammary gland caused by microorganisms. Staphylococcus spp. is the main causative agent of mastitis, with higher prevalence in cases of clinical and subclinical manifestations. The most common treatment is based on intramammary infusion of antibacterial agents. However, cure rates obtained with such drugs are not always effectives, because it may determine the emergence of resistant bacteria as well increase amounts of antibiotic residues in milk. Nevertheless, the treatment of bovine subclinical mastitis caused by Staphylococcus spp. in the lactation can be economically unviable. Alternative treatments of bovine mastitis with plant derived compounds have been described. The investigation of its antimicrobial activity against bacterial agents of mastitis is justifi able.Materials, Methods & Results: This study evaluated the antimicrobial activity of essential oil (EO) of Cinnamomum zeylanicum (cinnamon) and the fraction trans-cinnamaldehyde (TC) against 65 isolates of Staphyloco

Background: Milk production plays a role as a source of protein and constitutes an important socioeconomic factor for small farms. The lack of planning of the creators, together with the lack of specialized technical assistance, and the precarious hygienic and sanitary management, are barriers that hinder the development of the activity. Bovine and caprine mastitis is an infl ammation process of the mammary gland caused by microorganisms. Staphylococcus spp. is the main causative agent of mastitis, with higher prevalence in cases of clinical and subclinical manifestations. The most common treatment is based on intramammary infusion of antibacterial agents. However, cure rates obtained with such drugs are not always effectives, because it may determine the emergence of resistant bacteria as well increase amounts of antibiotic residues in milk. Nevertheless, the treatment of bovine subclinical mastitis caused by Staphylococcus spp. in the lactation can be economically unviable. Alternative treatments of bovine mastitis with plant derived compounds have been described. The investigation of its antimicrobial activity against bacterial agents of mastitis is justifi able.Materials, Methods & Results: This study evaluated the antimicrobial activity of essential oil (EO) of Cinnamomum zeylanicum (cinnamon) and the fraction trans-cinnamaldehyde (TC) against 65 isolates of Staphyloco