# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 2429 | 0 | 1.0000 | Antimicrobial resistance and toxigenic profiles of bacteria isolated from tropical shrimps (Farfantepenaeus notialis and Penaeus monodon) in Cameroun. OBJECTIVE: Post-harvest shrimp losses are a big problem due to the proliferation of spoilage bacteria. Presence and multiplication of these bacteria promotes the emergence of food-borne diseases. This study was carried out to characterize some spoilage bacteria from tropical brackish water shrimps and black tiger shrimps stored in ambient temperature (25 °C). RESULTS: 22 isolates of Bacillus spp; 09 isolates of Coagulase Negative Staphylococci (CNS) and 04 isolates of enterobacteria such as Pantoea spp (01); Serratia plymutica (01) and Serratia rubidaea (02) have been identified. Resistance and virulence genes were then detected. All isolates expressed resistance to at least three of antibiotics tested. 03 isolates of enterobacteria were susceptible to cetfazidim and amoxicillin-clavulanic acid. Bacillus spp showed total susceptibility to cefixim, ertapenem and cetfazidim. Staphylococci were susceptible to clindamycin. Pantoea spp was resistant to all antibiotics but exhibited intermediate susceptibility to amoxicillin-clavulanic acid. 04 isolates of Staphylococci were positive to mecA resistances genes. All the enterobacteria harbor no tetracycline resistance genes. All the isolates of Bacillus exhibited the presence of enterotoxin genes. Also, a high prevalence of 21 isolates to hemolytic enterotoxins was noted. 17 isolates from them kept ability to cell-lyse factor production like sphingomyelinase activities. The majority of Bacillus isolates identified by the present study poses a potential risk of food poisoning due to the prevalence of toxin genes found. | 2020 | 32727545 |
| 2388 | 1 | 0.9997 | Antibiotic resistance in lactic acid bacteria isolated from some pharmaceutical and dairy products. A total of 244 lactic acid bacteria (LAB) strains were isolated from 180 dairy and pharmaceutical products that were collected from different areas in Minia governorate, Egypt. LAB were identified phenotypically on basis of morphological, physiological and biochemical characteristics. Lactobacillus isolates were further confirmed using PCR-based assay. By combination of phenotypic with molecular identification Lactobacillus spp. were found to be the dominant genus (138, 76.7%) followed by Streptococcus spp. (65, 36.1%) and Lactococcus spp. (27, 15%). Some contaminant organisms such as (Staphylococcus spp., Escherichia coli, Salmonella spp., mould and yeast) were isolated from the collected dairy samples but pharmaceutical products were free of such contaminants. Susceptibility of LAB isolates to antibiotics representing all major classes was tested by agar dilution method. Generally, LAB were highly susceptible to Beta-lactams except penicillin. Lactobacilli were resistant to vancomycin, however lactococci and streptococci proved to be very susceptible. Most strains were susceptible to tetracycline and showed a wide range of streptomycin MICs. The MICs of erythromycin and clindamycin for most of the LAB were within the normal range of susceptibility. Sixteen Lactobacillus, 8 Lactococcus and 8 Streptococcus isolates including all tetracycline and/or erythromycin resistant strains were tested for the presence of tetracycline and/or erythromycin resistant genes [tet(M) and/or erm(B)]. PCR assays shows that some resistant strains harbor tet(M) and/or erm(B) resistance genes. | 2014 | 24948910 |
| 2406 | 2 | 0.9997 | Prevalence of antibiotic resistance genes in staphylococci isolated from ready-to-eat meat products. Prevalence of mecA, blaZ, tetO/K/M, ermA/B/C, aph, and vanA/B/C/D genes conferring resistance to oxacillin, penicillin, tetracycline, erythromycin, gentamicin, and vancomycin was investigated in 65 staphylococcal isolates belonging to twelve species obtained from ready-to-eat porcine, bovine, and chicken products. All coagulase negative staphylococci (CNS) and S. aureus isolates harbored at least one antibiotic resistance gene. None of the S. aureus possessed more than three genes, while 25% of the CNS isolates harbored at least four genes encoding resistance to clinically used antibiotics. In 15 CNS isolates the mecA gene was detected, while all S. aureus isolates were mecA-negative. We demonstrate that in ready-to-eat food the frequency of CNS harboring multiple antibiotic resistance genes is higher than that of multiple resistant S. aureus, meaning that food can be considered a reservoir of bacteria containing genes potentially contributing to the evolution of antibiotic resistance in staphylococci. | 2012 | 22844699 |
| 2400 | 3 | 0.9996 | Antimicrobial susceptibility and distribution of antimicrobial-resistance genes among Enterococcus and coagulase-negative Staphylococcus isolates recovered from poultry litter. Data on the prevalence of antimicrobial resistant enterococci and staphylococci from the poultry production environment are sparse in the United States. This information is needed for science-based risk assessments of antimicrobial use in animal husbandry and potential public-health consequences. In this study, we assessed the susceptibility of staphylococci and enterococci isolated from poultry litter, recovered from 24 farms across Georgia, to several antimicrobials of veterinary and human health importance. Among the 90 Enterococcus isolates recovered, E. hirae (46%) was the most frequently encountered species, followed by E. faecium (27%), E. gallinarum (12%), and E. faecalis (10%). Antimicrobial resistance was most often observed to tetracycline (96%), followed by clindamycin (90%), quinupristin-dalfopristin (62%), penicillin (53%), erythromycin (50%), nitrofurantoin (49%), and clarithromycin (48%). Among the 110 staphylococci isolates recovered, only coagulase-negative staphylococci (CNS) were identified with the predominant Staphylococcus species being S. sciuri (38%), S. lentus (21%), S. xylosus (14%) and S. simulans (12%). Resistance was less-frequently observed among the Staphylococcus isolates for the majority of antimicrobials tested, as compared with Enterococcus isolates, and was primarily limited to clarithromycin (71%), erythromycin (71%), clindamycin (48%), and tetracycline (38%). Multidrug resistance (MDR) phenotypes were prevalent in both Enterococcus and Staphylococcus; however, Enterococcus exhibited a statistically significant difference in the median number of antimicrobials to which resistance was observed (median = 5.0) compared with Staphylococcus species (median = 3.0). Because resistance to several of these antimicrobials in gram-positive bacteria may be attributed to the shuttling of common drug-resistance genes, we also determined which common antimicrobial-resistance genes were present in both enterococci and staphylococci. The antimicrobial resistance genes vat(D) and erm(B) were present in enterococci, vgaB in staphylococci, and mobile genetic elements Tn916 and pheromone-inducible plasmids were only identified in enterococci. These data suggest that the disparity in antimicrobial-resistance phenotypes and genotypes between enterococci and staphylococci isolated from the same environment is, in part, because of barriers preventing exchange of mobile DNA elements. | 2007 | 18251398 |
| 2407 | 4 | 0.9996 | Antibiotic resistance genes and identification of staphylococci collected from the production chain of swine meat commodities. Staphylococci harbouring antibiotic resistance (AR) genes may represent a hazard for human health and, as other resistant food-related bacteria, they contribute to the spread of AR. In this study, we isolated resistant staphylococci from an entire swine production chain and investigated the occurrence of 11 genes [aac(6')Ie-aph(2'')Ia, blaZ, mecA, vanA, vanB, ermA, ermB, ermC, tet(M), tet(O) and tet(K)] encoding resistance to some antibiotics largely used in clinical practice. The 66 resistant staphylococcal isolates were identified as Staphylococcus epidermidis (27 isolates), Staphylococcus aureus (12), Staphylococcus xylosus (12), Staphylococcus simulans (5), Staphylococcus pasteuri (4), Staphylococcus carnosus (3), Staphylococcus lentus (2) and Staphylococcus sciuri (1). Specific-PCR detection of AR genes showed the prevalence of the tet(K) gene in most of the isolates (89.4%), followed by tet(M) and ermC (about 75%); mecA was detected in more than half of S. aureus and S. epidermidis isolates. The genes vanA and vanB were not retrieved. It was found that a high proportion of coagulase-positive and -negative isolates are multidrug-resistant and some of them carry up to six AR genes. Our findings show that the swine production chain is a source of antibiotic-resistant staphylococci suggesting the importance of resistance surveillance in the food production environment. | 2008 | 17993395 |
| 5538 | 5 | 0.9996 | Phenotypic and genotypic antimicrobial susceptibility pattern of Streptococcus spp. isolated from cases of clinical mastitis in dairy cattle in Poland. Mastitis of dairy cattle is one of the most frequently diagnosed diseases worldwide. The main etiological agents of mastitis are bacteria of the genus Streptococcus spp., in which several antibiotic resistance mechanisms have been identified. However, detailed studies addressing this problem have not been conducted in northeastern Poland. Therefore, the aim of our study was to analyze, on phenotypic and genotypic levels, the antibiotic resistance pattern of Streptococcus spp. isolated from clinical cases of mastitis from dairy cattle in this region of Poland. The research was conducted using 135 strains of Streptococcus (Streptococcus uberis, n = 53; Streptococcus dysgalactiae, n = 41; Streptococcus agalactiae, n = 27; other streptococci, n = 14). The investigation of the antimicrobial susceptibility to 8 active substances applied in therapy in the analyzed region, as well as a selected bacteriocin (nisin), was performed using the minimum inhibitory concentration method. The presence of selected resistance genes (n = 14) was determined via PCR. We also investigated the correlation between the presence of resistance genes and the antimicrobial susceptibility of the examined strains in vitro. The highest observed resistance of Streptococcus spp. was toward gentamicin, kanamycin, and tetracycline, whereas the highest susceptibility occurred toward penicillin, enrofloxacin, and marbofloxacin. Additionally, the tested bacteriocin showed high efficacy. The presence of 13 analyzed resistance genes was observed in the examined strains [gene mef(A) was not detected]. In most strains, at least one resistance gene, mainly responsible for resistance to tetracyclines [tet(M), tet(K), tet(L)], was observed. However, a relationship between the presence of a given resistance gene and antimicrobial susceptibility on the phenotypic level was not always observed. | 2017 | 28601447 |
| 2885 | 6 | 0.9996 | Antimicrobial susceptibility of Streptococcus gallolyticus isolated from humans and animals. Susceptibilities to some antimicrobial agents and distribution of genes associated with resistance were examined in a total of 66 Streptococcus gallolyticus isolates and reference strains from various sources. All the tested bacteria were susceptible to vancomycin, penicillin G, and ampicillin. Most of the erythromycin-resistant isolates were observed in human clinical samples. Tetracycline and doxycycline resistance was prevalent in the isolates from human patients, diseased animals, and healthy broiler chickens, while the prevalence was significantly lower in the isolates from healthy mammals. All the isolates resistant to tetracycline possessed tet(M) and/or tet(L) and/or tet(O) genes. However, most isolates from healthy animals, which were susceptible to tetracycline, possessed the above-cited resistance genes, implying the potential ability for resistance under exposure to the corresponding antimicrobial agents. | 2013 | 23883848 |
| 2398 | 7 | 0.9996 | Antimicrobial-Resistant Enterococcus spp. in Wild Avifauna from Central Italy. Bacteria of the genus Enterococcus are opportunistic pathogens, part of the normal intestinal microflora of animals, able to acquire and transfer antimicrobial resistance genes. The aim of this study was to evaluate the possible role of wild avifauna as a source of antimicrobial-resistant enterococci. To assess this purpose, 103 Enterococcus spp. strains were isolated from the feces of wild birds of different species; they were tested for antimicrobial resistance against 21 molecules, vancomycin resistance, and high-level aminoglycosides resistance (HLAR). Furthermore, genes responsible for vancomycin, tetracycline, and HLAR were searched. E. faecium was the most frequently detected species (60.20% of isolates), followed by E. faecalis (34.95% of isolates). Overall, 99.02% of the isolated enterococci were classified as multidrug-resistant, with 19.41% extensively drug-resistant, and 2.91% possible pan drug-resistant strains. Most of the isolates were susceptible to amoxicillin/clavulanic acid (77.67%) and ampicillin (75.73%), with only 5.83% of isolates showing an ampicillin MIC ≥ 64 mg/L. HLAR was detected in 35.92% of isolates, mainly associated with the genes ant(6)-Ia and aac(6')-Ie-aph(2″)-Ia. Few strains (4.85%) were resistant to vancomycin, and the genes vanA and vanB were not detected. A percentage of 54.37% of isolates showed resistance to tetracycline; tet(M) was the most frequently detected gene in these strains. Wild birds may contribute to the spreading of antimicrobial-resistant enterococci, which can affect other animals and humans. Constant monitoring is essential to face up to the evolving antimicrobial resistance issue, and monitoring programs should include wild avifauna, too. | 2022 | 35884106 |
| 2702 | 8 | 0.9996 | Assessment of the presence of multidrug-resistant Escherichia coli, Salmonella and Staphylococcus in chicken meat, eggs and faeces in Mymensingh division of Bangladesh. The emergence of bacteria that is resistant to several drugs of clinical importance poses a threat to successful treatment, a phenomenon known as multidrug resistance that affects diverse classes of antibiotics. The purpose of this study was to evaluate the prevalence of multidrug-resistant Escherichia coli, Salmonella spp. and Staphylococcus aureus in chicken egg, meat and faeces from four districts of Bangladesh. A total of 120 chicken samples were collected from different poultry farms. Conventional culture and molecular detection methods were used for identification of bacterial isolates from the collected samples followed by antibiotic susceptibility test through the disc diffusion method, finally antibiotic resistant genes were detected by PCR. E. coli, Salmonella spp. and Staphylococcus aureus were detected in meat, egg and faecal samples. Antimicrobial susceptibility results revealed isolates from faeces were 100 % resistant to amoxicillin, while all S. aureus and Salmonella sp. from faeces were resistant to doxycycline, tetracycline and erythromycin. Salmonella spp. isolates from eggs indicated 100 % resistance to erythromycin, amoxycillin, while E. coli were 100 % resistant to erythromycin. E. coli and S. aureus from meat were 100 % resistant to amoxicillin and erythromycin. However, Salmonella spp. from eggs were 100 % susceptible to doxycycline, gentamicin, levofloxacin and tetracycline. The mecA and aac(3)-IV genes were only found in S. aureus and E. coli, respectively. The Sul1, tetB, and aadA1 were highest in Salmonella spp. and S. aureus, while the sul1, tetA and bla (SHV) were higher in E. coli. Isolates from all samples were multidrug resistant. These findings indicate a high risk of transmission of resistance genes from microbial contamination to food of animal origin. The study emphasizes the need for effective biosecurity measures, responsible antibiotic use, and strict regulations in poultry production to prevent the spread of antibiotic resistance. | 2024 | 39281621 |
| 2700 | 9 | 0.9996 | Prevalence of Salmonella Typhimurium and Salmonella Enteritidis isolated from poultry meat: virulence and antimicrobial-resistant genes. Salmonellosis, a zoonotic disease, is one of the leading causes of foodborne illness worldwide. It is responsible for most infections caused by consumption of contaminated food. In recent years, a significant increase in the resistance of these bacteria to common antibiotics has been observed, posing a serious threat to global public health. The aim of this study was to investigate the prevalence of virulent antibiotic-resistant Salmonella spp. strains in Iranian poultry markets. A total of 440 chicken meat samples were randomly selected from meat supply and distribution facilities in Shahrekord and tested for bacteriological contamination. After culturing and isolating the strains, identification was performed using the classical bacteriological method and PCR. To determine antibiotic resistance, a disc diffusion test was performed according to the recommendations of the French Society of Microbiology. PCR was used to detect resistance and virulence genes. Only 9% of the samples were positive for Salmonella. These were Salmonella typhimurium isolates. All Salmonella typhimurium serotypes tested positive for the rfbJ, fljB, invA and fliC genes. Resistance to TET, cotrimoxazole, NA, NIT, piperacillin/tazobactam and other antibiotics was found in 26 (72.2%), 24 (66.7%), 22 (61.1%) and 21 (58.3%) isolates, respectively. The sul1, sul2 and sul3 genes were present in 20, 12 and 4 of 24 cotrimoxazole-resistant bacteria, respectively. Chloramphenicol resistance was found in six isolates, but more isolates tested positive for the floR and cat two genes. In contrast, 2 (33%) of the cat three genes, 3 (50%) of the cmlA genes and 2 (34%) of the cmlB genes were all positive. The results of this investigation showed that Salmonella typhimurium is the most common serotype of the bacterium. This means that most of the antibiotics commonly used in the livestock and poultry industries are ineffective against most Salmonella isolates, which is important for public health. | 2023 | 37322421 |
| 2658 | 10 | 0.9996 | Rapid detection of major enterotoxin genes and antibiotic resistance of Staphylococcus aureus isolated from raw milk in the Yazd province, Iran. INTRODUCTION: Raw milk is a nutrient-rich food, but it may harbour harmful bacteria, such as enterotoxigenic Staphylococcus aureus (S. aureus), which can cause staphylococcal food poisoning. Antibiotic resistance of S. aureus in raw milk can increase the risk of such infections, particularly among susceptible individuals. OBJECTIVE: This study aimed to investigate the prevalence of enterotoxin genes a, d, g, i and j and the antibiotic resistance of S. aureus isolated from raw milk samples. METHODS: During a 6-month sampling period, 60 raw milk specimens were obtained from diverse locations in Yazd province, Iran. Antibiogram profiling was conducted via the disc diffusion method. In addition, staphylococcal enterotoxin (SE) genes a, d, g, i, and j were detected through real-time PCR analysis. RESULTS: Bacteriological assays confirmed the presence of S. aureus in 11 samples (18.3%). All isolates demonstrated 100% resistance to penicillin G but exhibited sensitivity to vancomycin, while resistance to other antibiotics ranged from 36.4% to 45.5%. The prevalence of enterotoxin genes in these strains showed variable distribution, with sea being the predominant SE (45.5%), followed by sed (36.4%), seg (18.2), sej and sei (9.1% each). CONCLUSIONS: This study discovered the presence of multiple enterotoxins in S. aureus strains obtained from raw milk samples. These strains also demonstrated resistance to a variety of antibiotics. Since enterotoxigenic S. aureus is known to cause human food poisoning, monitoring food hygiene practices, especially during raw milk production, is critical. | 2024 | 38519836 |
| 2391 | 11 | 0.9996 | Antimicrobial resistance and presence of virulence factor genes in Arcanobacterium pyogenes isolated from the uterus of postpartum dairy cows. Arcanobacterium pyogenes is considered the most significant bacterium involved in the pathogenesis of metritis in cattle. Infections caused by antimicrobial-resistant bacteria are a great challenge in both human and veterinary medicine. The purpose of this study was to present an overview of antimicrobial resistance in A. pyogenes isolated from the uteruses of postpartum Holstein dairy cows and to identify virulence factors. Seventy-two A. pyogenes isolates were phenotypically characterized for antimicrobial resistance to amoxicillin, ampicillin, ceftiofur, chloramphenicol, florfenicol, oxytetracycline, penicillin, spectinomycin, streptomycin and tetracycline by the broth microdilution method. Presence of virulence factor genes of A. pyogenes was investigated. Isolates exhibited resistance to all antimicrobial agents tested; high levels of resistance were found to amoxicillin (56.9%); ampicillin (86.1%), chloramphenicol (100%), florfenicol (59.7%), oxytetracycline (54.2%), penicillin (86.1%) and tetracycline (50%). Of all isolates, 69 (95.8%) were resistant to at least 2 of the antimicrobial agents tested and multidrug resistance (resistant to at least 3 antimicrobials) was observed in 64 (88.9%) of the A. pyogenes isolates. The major multidrug resistance profile was found for chloramphenicol-ampicillin-penicillin-florfenicol-amoxicillin-tetracycline, which was observed in 21 (29.2%) multidrug resistant isolates. No isolate was resistant to all nine antimicrobial agents tested but four isolates (5.6%) were resistant to eight antimicrobials. The information highlights the need for prudent use of specific antimicrobial agents. All four virulence factor genes occurred in isolates from normal puerperium and clinical metritis; however, the fimA gene was present in significantly higher frequency in isolates from metritis cows. | 2010 | 20346602 |
| 2677 | 12 | 0.9996 | Detection of Staphylococcus Isolates and Their Antimicrobial Resistance Profiles and Virulence Genes from Subclinical Mastitis Cattle Milk Using MALDI-TOF MS, PCR and Sequencing in Free State Province, South Africa. Staphylococcus species are amongst the bacteria that cause bovine mastitis worldwide, whereby they produce a wide range of protein toxins, virulence factors, and antimicrobial-resistant properties which are enhancing the pathogenicity of these organisms. This study aimed to detect Staphylococcus spp. from the milk of cattle with subclinical mastitis using MALDI-TOF MS and 16S rRNA PCR as well as screening for antimicrobial resistance (AMR) and virulence genes. Our results uncovered that from 166 sampled cows, only 33.13% had subclinical mastitis after initial screening, while the quarter-level prevalence was 54%. Of the 50 cultured bacterial isolates, MALDI-TOF MS and 16S rRNA PCR assay and sequencing identified S. aureus as the dominant bacteria by 76%. Furthermore, an AMR susceptibility test showed that 86% of the isolates were resistant to penicillin, followed by ciprofloxacin (80%) and cefoxitin (52%). Antimicrobial resistance and virulence genes showed that 16% of the isolates carried the mecA gene, while 52% of the isolates carried the Lg G-binding region gene, followed by coa (42%), spa (40%), hla (38%), and hlb (38%), whereas sea and bap genes were detected in 10% and 2% of the isolates, respectively. The occurrence of virulence factors and antimicrobial resistance profiles highlights the need for appropriate strategies to control the spread of these pathogens. | 2024 | 38200885 |
| 2679 | 13 | 0.9996 | Detection and Molecular Characterization of Staphylococci from Eggs of Household Chickens. Eggs are a healthy and nutritious food source, but may be contaminated by bacteria. Previous studies have reported the presence of staphylococci in eggs of farmed chickens, but no study has evaluated the staphylococcal population of eggs from household chickens. In this study, staphylococci from eggs (n = 275) of household chickens collected from November 2016 to March 2017 from different villages of Khyber Pakhtunkhwa province, Pakistan, were characterized. Seven species of staphylococci were identified from 65 eggs, including the predominant species, Staphylococcus xylosus (49/275; 17.8%). S. xylosus isolates (n = 73) were tested for antimicrobial susceptibility, presence of resistance genes, genetic relatedness, and inhibitory activity against other bacteria. The majority of isolates were resistant to oxacillin (83.6%) and tetracycline (24.7%), but also exhibited resistance to daptomycin and linezolid (5.5% each). Of the 10 resistance genes tested, isolates were only positive for mecA (35.6%; 26/73), mecC/C1 (2.7%; 2/73), and tet(K) (14/73; 19%). Using pulsed-field gel electrophoresis (PFGE), nine clusters had identical PFGE patterns. Isolates produced inhibitory activity against a broad spectrum of bacteria; 20.5%, 19.2%, 17.8%, and 16.4% of S. xylosus were able to inhibit growth of Salmonella enterica serotype Typhi, methicillin-susceptible Staphylococcus aureus, Escherichia coli, and methicillin-resistant Staphylococcus aureus, respectively. This study demonstrated the presence of genetically related antimicrobial-resistant S. xylosus from eggs from household chickens. Like table eggs, eggs of household chickens also contain staphylococci that may be resistant to antimicrobials used to treat human infections. These data will allow comparison between staphylococci from eggs from different sources and may indicate the relative safety of eggs from household chickens. Further study of these egg types and their microbial composition is warranted. | 2019 | 31009262 |
| 5601 | 14 | 0.9996 | Presence of Staphylococcus spp. carriers of the mecA gene in the nasal cavity of piglets in the nursery phase. The presence of Staphylococcus spp. resistant to methicillin in the nasal cavity of swine has been previously reported. Considering the possible occurrence of bacterial resistance and presence of resistance genes in intensive swine breeding and the known transmissibility and dispersion potential of such genes, this study aimed to investigate the prevalence of resistance to different antibiotics and the presence of the mecA resistance gene in Staphylococcus spp. from piglets recently housed in a nursery. For this, 60 nasal swabs were collected from piglets at the time of their housing in the nursery, and then Staphylococcus spp. were isolated and identified in coagulase-positive (CoPS) and coagulase-negative (CoNS) isolates. These isolates were subjected to the disk-diffusion test to evaluate the bacterial resistance profile and then subjected to molecular identification of Staphylococcus aureus and analyses of the mecA gene through polymerase chain reaction. Of the 60 samples collected, 60 Staphylococcus spp. were isolated, of which 38 (63.33%) were classified as CoNS and 22 (36.67%) as CoPS. Of these, ten (45.45%) were identified as Staphylococcus aureus. The resistance profile of these isolates showed high resistance to different antibiotics, with 100% of the isolates resistant to chloramphenicol, clindamycin, and erythromycin, 98.33% resistant to doxycycline, 95% resistant to oxacillin, and 85% resistant to cefoxitin. Regarding the mecA gene, 27 (45%) samples were positive for the presence of this gene, and three (11.11%) were phenotypically sensitive to oxacillin and cefoxitin. This finding highlights the importance of researching the phenotypic profile of resistance to different antimicrobials and resistance genes in the different phases of pig rearing to identify the real risk of these isolates from a One Health perspective. The present study revealed the presence of samples resistant to different antibiotics in recently weaned production animal that had not been markedly exposed to antimicrobials as growth promoters or even as prophylactics. This information highlights the need for more research on the possible sharing of bacteria between sows and piglets, the environmental pressure within production environments, and the exposure of handlers during their transport, especially considering the community, hospital, and political importance of the presence of circulating resistant strains. | 2023 | 36634542 |
| 2886 | 15 | 0.9996 | Comparison of antimicrobial resistance patterns in enterococci from intensive and free range chickens in Australia. Resistance to antimicrobials in enterococci from poultry has been found throughout the world and is generally recognized as associated with antimicrobial use. This study was conducted to evaluate the phenotypic and genotypic profile of enterococcal isolates of intensive (indoor) and free range chickens from 2008/09 and 2000 in order to determine the patterns of antimicrobial resistance associated with different management systems. The minimum inhibitory concentrations in faecal enterococci isolates were determined by agar dilution. Resistance to bacitracin, ceftiofur, erythromycin, lincomycin, tylosin and tetracycline was more common among meat chickens (free range and intensive) than free range egg layers (P<0.05). Isolates were evaluated by polymerase chain reaction for bacitracin (bcrR), tylosin (ermB), tetracycline (tet(L), tet(M), tet(O), tet(S), and tet(K)), gentamicin (aac6-aph2), vancomycin (vanC and vanC2), ampicillin (pbp5) and integrase (int) genes. Resistance to bacitracin, erythromycin and tetracycline were found to be correlated with the presence of bcrR, ermB, and tet genes in most of the isolates collected from meat chickens. Most bacteria encoding ermB gene were found to express cross-resistance to erythromycin, tylosin and lincomycin. No significant difference was found in these resistance genes between isolates sampled in 2000 and 2008/09 (P<0.5). Unlike the enterococcal strains sampled in 2000, the 2008/09 isolates were found to be susceptible to vancomycin and virginiamycin. This study provides evidence that, despite strict regulation imposed on antibiotic usage in poultry farming in Australia, antimicrobial resistance is present in intensively raised and free range meat chickens. | 2013 | 23391181 |
| 5902 | 16 | 0.9996 | Antimicrobial Resistance Profiles of Listeria monocytogenes and Listeria innocua Isolated from Ready-to-Eat Products of Animal Origin in Spain. The objective of this work was to investigate the antimicrobial resistance in Listeria spp. isolated from food of animal origin. A total of 50 Listeria strains isolated from meat and dairy products, consisting of 7 Listeria monocytogenes and 43 Listeria innocua strains, were characterized for antimicrobial susceptibility against nine antimicrobials. The strains were screened by real-time PCR for the presence of antimicrobial resistance genes: tet M, tet L, mef A, msr A, erm A, erm B, lnu A, and lnu B. Multidrug resistance was identified in 27 Listeria strains, 4 belonging to L. monocytogenes. Resistance to clindamycin was the most common resistance phenotype and was identified in 45 Listeria strains; the mechanisms of resistance are still unknown. A medium prevalence of resistance to tetracycline (15 and 9 resistant and intermediate strains) and ciprofloxacin (13 resistant strains) was also found. Tet M was detected in Listeria strains with reduced susceptibility to tetracycline, providing evidence that both L. innocua and L. monocytogenes displayed acquired resistance. The presence of antimicrobial resistance genes in L. innocua and L. monocytogenes indicates that these genes may be transferred to commensal and pathogenic bacteria via the food chain; besides this, antibiotic resistance in L. monocytogenes could compromise the effective treatment of listeriosis in humans. | 2017 | 28355096 |
| 2909 | 17 | 0.9996 | Determination of the prevalence of antimicrobial resistance genes in canine Clostridium perfringens isolates. Clostridium perfringens is a well documented cause of a mild self-limiting diarrhea and a potentially fatal acute hemorrhagic diarrheal syndrome in the dog. A recent study documented that 21% of canine C. perfringens isolates had MIC's indicative of resistance to tetracycline, an antimicrobial commonly recommended for treatment of C. perfringens-associated diarrhea. The objective of the present study was to further evaluate the antimicrobial susceptibility profiles of these isolates by determining the prevalence of specific resistance genes, their expression, and ability for transference between bacteria. One hundred and twenty-four canine C. perfringens isolates from 124 dogs were evaluated. Minimum inhibitory concentrations of tetracycline, erythromycin, tylosin, and metronidazole were determined using the CLSI Reference Agar Dilution Method. All isolates were screened for three tetracycline resistance genes: tetA(P), tetB(P) and tetM, and two macrolide resistance genes: ermB and ermQ, via PCR using primer sequences previously described. Ninety-six percent (119/124) of the isolates were positive for the tetA(P) gene, and 41% (51/124) were positive for both the tetA(P) and tetB(P) genes. No isolates were positive for the tetB(P) gene alone. Highly susceptible isolates (MIC< or = 4 microg/ml) were significantly more likely to lack the tetB(P) gene. One isolate (0.8%) was positive for the ermB gene, and one isolate was positive for the ermQ gene. The tetM gene was not found in any of the isolates tested. Two out of 15 tested isolates (13%) demonstrated transfer of tetracycline resistance via bacterial conjugation. Tetracycline should be avoided for the treatment of C. perfringens-associated diarrhea in dogs because of the relatively high prevalence of in vitro resistance, and the potential for conjugative transfer of antimicrobial resistance. | 2006 | 16330169 |
| 2684 | 18 | 0.9996 | Prevalence, characterization and antimicrobial resistance of Listeria monocytogenes isolated from beef meat in Meknes city, Morocco. INTRODUCTION: Listeria monocytogenes is one of the most pathogenic bacteria related to the consumption of contaminated food. This study aims to determine the prevalence of L. monocytogenes in raw beef meat in Meknes city of Morocco, to evaluate its pathogenicity and resistance to antimicrobials. METHODS: During four seasons, a total of 140 samples were collected from supermarkets, butcheries and Souk (weekly traditional market). The PCR method was used to examine the presence of specific and virulence genes in the isolated strains, and also to identify their serotypes. The antimicrobial resistance was determined. RESULTS: The results show a prevalence of 7.14% which depends on retail sites and also on the season's variation. The majority of the strains were detected in butcheries (6 strains), and supermarkets (4 strains). Moreover, the majority of strains were detected during summer (50%). Concerning virulence genes, the seven researched genes were detected in 100% of isolated strains. The majority of strains were of the (1/2a, 1/2c, 3a and 3c) serogroup (70%), while two of them were of the (1/2b, 3b, 4b and 4d) serogroup (20%). All isolates were resistant to at least one antimicrobial, while three strains were resistant to nine tested antimicrobials. However, they were highly susceptible to amikacin, imipenem, gentamicin, sulfamethoxazole and chloramphenicol. CONCLUSIONS: According to results, isolated L. monocytogenes from analyzed beef meat shows a high level of pathogenicity and resistance to the most used antimicrobials in listeriosis therapy, which calls for the severe application of quality systems at the slaughterhouses and retail sites level. | 2020 | 32656103 |
| 5534 | 19 | 0.9996 | Antibiotic resistance in faecal microbiota of Greek healthy infants. Increasing use of antibiotics for the treatment of infectious diseases and also for non-therapeutic reasons (agriculture, animal husbandry and aquaculture) has led to the increasing incidence of antibiotic resistance and the ineffectiveness of antimicrobial treatment. Commensal intestinal bacteria are very often exposed to the selective pressure of antimicrobial agents and may constitute a reservoir of antibiotic resistance determinants that can be transferred to pathogens. The present study aimed to investigate the antibiotic susceptibility profile and the presence of selected resistance genes in cocci isolated from the faecal microbiota of 35 healthy, full-term infants at 4, 30 and 90 days after delivery. A total of 148 gram-positive, catalase-negative cocci were isolated and tested for susceptibility to 12 different antibiotics by disk-diffusion technique. Multiplex PCR analysis was performed for the identification of Enterococcus spp. isolates and the simultaneous detection of vancomycin-resistance genes. PCR-based methodology was used also for identification of tetracycline and erythromycin resistance determinants. Identification results indicated E. faecalis as the predominant species (81 strains), followed by E. faecium, E. casseliflavus/E. flavescens and E. gallinarum. High prevalence of resistance to tetracycline (39.9%), erythromycin (35.1%), vancomycin (19.6%) and to nucleic acid synthesis inhibitors was detected. PCR data revealed 24 out of 52 erythromycin-resistant isolates carrying the ermB gene and 32 out of 59 tetracycline-resistant strains carrying tet genes, with tet(L) determinant being the most frequently detected. Only intrinsic vancomycin resistance (vanC1 and vanC2/C3) was reported among tested isolates. In conclusion, erythromycin and tetracycline acquired resistant traits are widespread among faecal cocci isolates from Greek, healthy infants under no apparent antimicrobial selective pressure. | 2010 | 21831766 |