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Molecular analysis of virulence genes stx1, stx2, eaeA and hlyA in Escherichia coli isolated from cloacal samples in wild pigeons (Columba livia) and determination of their antibiotic resistance
2017
Mohammadzadeh, Abdolmajid | Mahmoodi, Pezhman | Ashrafi tamai, Iradj | Sharifi, Aram
BACKGROUND: Pigeons can be carriers for some human and animal pathogens, one of the most important of which is Escherichia coli. OBJECTIVES: This bacterium is responsible for outbreaks of many human diseases. Our objective was to determine the prevalence of Escherichia coli in cloacal area of pigeons in Tehran city (Iran), and determine the prevalence of some virulence genes and also antibiotics resistance pattern of isolates. METHODS: Altogether 117 samples of pigeon feces were collected from cloacal swab. The identification of bacteria was done by culture on differential culture media. Then antibiotic susceptibility test was performed by disk diffusion method. Isolates were tested for the presence of virulence genes stx1, stx2, eae and hlyA using multiplex polymerase chain reaction. RESULTS: Escherichia coli were detected in 82.9% of 277 samples from pigeons. Sulfamethoxazole was the least effective drug (85.6% resistance), followed by tetracycline (83.5%). No resistance was detected to co-amoxiclav. The prevalence of stx1, stx2 and eaeA is 3.09%, 6.18% and 2.06% respectively and hlyA was not found in any of isolates. CONCLUSIONS: The frequency of stx1 and stx2 distribution in animals and birds is not well understood as yet. Due to the close relationship of humans with birds like pigeons and presence of STEC strains in apparently healthy birds, necessitates considering precise regulations to restrict and prevent the prevalence of this life- threatening virus in Iran.
显示更多 [+] 显示较少 [-]Microbiome and antimicrobial resistance genes in microbiota of cloacal samples from European herring gulls (Larus argentatus)
2017
Merkeviciene, Lina | Ruzauskaite, Neda | Klimiene, Irena | Siugzdiniene, Rita | Dailidaviciene, Jurgita | Virgailis, Marius | Mockeliunas, Raimundas | Ruzauskas, Modestas
Introduction: The aim of the study was to determine microbiota in the cloacal samples of European herring gulls (Larus argentatus) and to compare a variety of genes encoding antimicrobial resistance in cultivable and non-cultivable bacteria. Material and Methods: Cloacal samples from European herring gulls were collected from a Kaunas city dump. Cultivable microbiota were isolated, their microbial susceptibility was tested, and genes encoding antimicrobial resistance were detected. Additionally, a metagenomic study was performed using Next-Generation Sequencing (NGS). Results: In total, 697 different operational taxonomic units at genus level were detected; however, only 63 taxonomic units were detected at the amount of ≥0.1% of the total number of DNA copies. Catellicoccus marimammalium was found to have the highest prevalence. The bacterial amount of other genera was up to 5% with the most highly prevalent being Psychrobacter (4.7%), Helicobacter (4.5%), unclassified Enterococcaceae (3.2%), Pseudomonas (2.9%), and Brachyspira (2.6%). Conclusions: C. marimammalium are predominant microbiota in the cloacal samples of Larus argentatus. This species of gulls is a reservoir of bacteria carrying a wide-spectrum of genes encoding antimicrobial resistance. The same genes were detected in both cultivable microbiota and in the total DNA of the samples.
显示更多 [+] 显示较少 [-]Toxinotyping and antimicrobial resistance of Clostridium perfringens isolated from processed chicken meat products
2017
Hamza, Dalia | Dorgham, Sohad | Ḥakīm, Ashraf
Introduction: The toxinotyping and antimicrobial susceptibility of Clostridium perfringens strains isolated from processed chicken meat were determined. Material and Methods: Two hundred processed chicken meat samples from luncheon meats, nuggets, burgers, and sausages were screened for Clostridium perfringens by multiplex PCR assay for the presence of alpha (cpa), beta (cpb), epsilon (etx), iota (ia), and enterotoxin toxin (cpe) genes. The C. perfringens isolates were examined in vitro against eight antibiotics (streptomycin, amoxicillin, ampicillin, ciprofloxacin, lincomycin, cefotaxime, rifampicin, and trimethoprim-sulfamethoxazole) Results: An overall of 32 C. perfringens strains (16%) were isolated from 200 processed chicken meat samples tested. The prevalence of C. perfringens was significantly dependent on the type of toxin genes detected (P = 0.0), being the highest in sausages (32%), followed by luncheon meats (24%), burgers (6%), and nuggets (2%). C. perfringens type A was the most frequently present toxinotype (24/32; 75%), followed by type D (21.9 %) and type E (3.1%). Of the 32 C. perfringens strains tested, only 9 (28%) were enterotoxin gene carriers, with most representing type A (n = 6). C. perfringens strains differed in their resistance/susceptibility to commonly used antibiotics. Most of the strains tested were sensitive to ampicillin (97%) and amoxicillin (94%), with 100% of the strains being resistant to streptomycin and lincomycin. It is noteworthy that the nine isolates with enterotoxigenic potential had a higher resistance than the non-enterotoxigenic ones. Conclusion: The considerably high C. perfringens isolation rates from processed chicken meat samples and resistance to some of the commonly used antibiotics indicate a potential public health risk. Recent information about the isolation of enterotoxigenic C. perfringens type E from chicken sausage has been reported.
显示更多 [+] 显示较少 [-]Presence of methicillin-resistant Staphylococcus aureus in slaughterhouse environment, pigs, carcasses, and workers
2017
Ivbule, Meldra | Miklaševičs, Edvīns | Čupāne, Liene | Bērziņa, Laima | Bālinš, Andris | Valdovska, Anda
Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) is a highly resistant and difficult to cure zoonotic microorganism, which makes up a large part of food toxic infections and has shown high prevalence among pig population all over the world. The aim of the study was to establish the occurrence of MRSA in slaughterhouses, evaluate its antimicrobial resistance, and verify whether there are any differences or similarities with reference to other European countries. Material and Methods: A total of 100 pigs, 105 carcasses, 19 workers, and 24 samples from the environment of several slaughterhouses were examined by conventional microbial and molecular methods. Results: In total, 78 MRSA isolates were found. MRSA prevalence in slaughtered pigs varied from 8.0% to 88.6% depending on the slaughterhouse, reaching higher prevalence in slaughterhouses with higher slaughter capacity. In total, 21.1% of all workers were carriers of MRSA and 6.7% of carcasses were contaminated with MRSA. The 98.2% of MRSA isolates were resistant to penicillin, 89.1% to tetracycline, 60.1% to erythromycin, 65.5% to gentamycin, and 15 different spa types were found, among which spa type t01333 was most widespread. Conclusion: The study indicated that MRSA prevalence and spa types differed according to slaughterhouse slaughter capacity and good hygiene practices. Quite high MRSA occurrence among slaughterhouse workers is one of the main factors which increase pork contamination risk.
显示更多 [+] 显示较少 [-]Direct repeat unit (dru) typing and antimicrobial resistance of methicillin-resistant Staphylococcus pseudintermedius isolated from dogs in Atlantic Canada
2017
Saab, M. E. | Weese, J. S. | McClure, J. T.
There are few reports investigating the characterization of methicillin-resistant Staphylococcus pseudintermedius (MRSP) in dogs in Canada and none from Atlantic Canada. The objectives of this study were to strain type MRSP isolates cultured at a regional diagnostic laboratory using direct repeat unit (dru) typing and to describe their antimicrobial resistance profiles. Ninety-four isolates recovered from dogs between 2010 and 2012 had dru typing, cluster analysis, and antimicrobial susceptibility testing done. The majority of isolates belonged to type dt11a (30.9%), dt10h (24.5%), dt9a (18.1%), and dt11af (10.6%) with the remaining 15.9% of isolates distributed among 13 dru types. The predominant dru types identified were similar in Ontario; however, cluster 9a appears to be less common in Atlantic Canada. A significant difference in the distribution of clusters among Atlantic provinces was detected (P = 0.01). Resistance to ≥ 2 non-β-lactam antimicrobials was observed in 71.4% of the isolates. The MRSP isolates from this study were notably less resistant than those reported in the literature. A more comprehensive study of the MRSP dru types could help further elucidate the distribution of this pathogen in Canada.
显示更多 [+] 显示较少 [-]Patterns of antibiotic resistance in Escherichia coli isolated from fresh and recycled poultry litter
2017
Sung, H.W., Kangwon National University, Chuncheon, Republic of Korea | Choi, K.S., Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea | Kwon, H.M., Kangwon National University, Chuncheon, Republic of Korea | Lee, Y.J., Kyungpook National University, Daegu, Republic of Korea
The isolation rate of Escherichia (E.) coli in poultry litter was investigated at 44 broiler farms, 20 that used fresh litter and 24 that used recycled litter. The patterns of resistance to antibiotics of the E. coli isolates were compared. In litter sampled before the rearing period, the isolation rate of E. coli was higher at farms that used fresh litter; E. coli was present in the litter in 94.5% (35 out of 37 flocks tested) of the farms that used fresh litter vs. 51.2% (21 out of 41 flocks) of the farms that used recycled litter. The susceptibility of the 93 isolates of E. coli to 13 antibiotics was studied. Before the rearing period, E. coli isolates from the farms that recycled litter showed higher resistance rates than isolates from farms that replaced litter with fresh litter. Comparing the antibiotic resistance patterns of isolates from litter sampled before and at the end of the rearing period, the antibiotic resistance rates at the end of the rearing period increased dramatically compared with rates before the rearing period.
显示更多 [+] 显示较少 [-]Alterations in conjunctival bacteria and antimicrobial susceptibility during topical administration of ofloxacin after cataract surgery in dogs
2017
OBJECTIVE To evaluate changes in conjunctival bacteria and antimicrobial susceptibility of bacteria after cataract surgery in dogs. ANIMALS 16 client-owned dogs. PROCEDURES Samples for aerobic and anaerobic culture were obtained from the conjunctival fornices of both eyes of dogs 24 hours before (week 0) and 1, 3, and 6 weeks after cataract surgery. Topical administration of ofloxacin (every 6 hours) was initiated 12 hours before surgery and continued for 3 weeks. In vitro antimicrobial susceptibility was determined by Kirby-Bauer disk diffusion and a commercially available test for ofloxacin. RESULTS Frequency of positive culture results was significantly higher at week 6 than at weeks 0 and 1. Bacterial load was more likely to be moderate or high at weeks 3 and 6 than at weeks 0 and 1. The most frequently cultured organism was Staphylococcus pseudintermedius (21/78 [26.9%]), followed by coagulase-negative Staphylococcus spp (19/78 [24.4%]). Staphylococcus pseudintermedius was the organism most frequently cultured at weeks 0 (5/12), 1 (4/12), and 6 (8/19), whereas frequency of this organism was lowest at week 3 (1/20). In contrast, coagulase-negative Staphylococcus spp were the most frequently cultured organisms at week 3 (10/20). There was a significant increase in the proportion of organisms resistant to ofloxacin at week 3, compared with the proportion at week 0. CONCLUSIONS AND CLINICAL RELEVANCE The number of bacterial organisms increased and the population of conjunctival bacteria was altered and had a higher proportion resistant to ofloxacin during the 6 weeks after cataract surgery for dogs treated by use of this protocol.
显示更多 [+] 显示较少 [-]Phylogenetic analysis of Escherichia coli isolated from broilers with colibacillosis based on gyrA gene sequences
2017
Shamsi, H. | Mardani, K. | Ownagh, A.
Escherichia coli isolates from chickens with colibacillosis were assigned to phylogenetic groups based on multiplex polymerase chain reaction (PCR) and antibacterial resistance of E. coli belonging to these groups was examined. Furthermore, the gyrA gene of isolates was sequenced and a phylogenetic tree was generated. A total of 84 E. coli isolates were grouped using multiplex PCR of TSPE4.C2, chuA, yjaA, and gadA molecular markers. Four phylogenetic groups were identified with strains divided as follows: 16 in group A (19.05%), 17 in group B1 (20.24%), 23 in group B2 (27.38%), and 28 in group D (33.33%). Escherichia coli isolates belonging to phylogenetic groups B2 and D were resistant to Soltrim and Flumequine unlike the majority of E. coli isolates that belonged to groups A and B1, and which were susceptible to these antibiotics. The phylogenetic results based on gyrA gene sequences from multiplex PCR revealed that E. coli phylogenetic grouping was in accordance with the clusters obtained in the phylogenetic tree. In conclusion, the comparative sequence analysis of gyrA sequences provides a firm framework for an accurate classification of E. coli and related taxa and may constitute a pertinent phylogenetic marker for E. coli.
显示更多 [+] 显示较少 [-]Identification of microbiome with 16S rRNA gene pyrosequencing and antimicrobial effect of egg white in bovine mastitis
2017
Kim, D., Seoul National University, Seoul, Republic of Korea | Kim, E.K., Seoul National University, Seoul, Republic of Korea | Seong, W.J., Seoul National University, Seoul, Republic of Korea | Ro, Y., Seoul National University, Seoul, Republic of Korea | Ko, D.S., Seoul National University, Seoul, Republic of Korea | Kim, N.H., Institutes of GreenBio Science Technology, Pyeongchang, Republic of Korea | Kim, J.H., Institutes of GreenBio Science Technology, Pyeongchang, Republic of Korea | Kwon, H.J., Seoul National University, Seoul, Republic of Korea
Bovine mastitis is an important microbial disease in the dairy industry. We investigated the frequencies of bacterial pathogens in 62 farms and pathogen antibiotic resistance from mastitis samples (n = 748). We tested the antimicrobial activity of chicken and duck egg white and lysozyme purified from chicken egg white. Moreover, we compared the microbiomes of normal and mastitic raw milk obtained by 16S rRNA gene pyrosequencing and culture methods. The results showed that the frequencies of Gram-positive pathogens (Enterococcus faecalis 37% and Staphylococcus aureus 36%) were higher than that of a Gram-negative pathogen (Escherichia coli 15%). Resistance frequencies to ampicillin and norfloxacin were lowest in Staphylococcus aureus (21%), Enterococcus faecalis (23%), and Escherichia coli (33%), and the antimicrobial activity of chicken egg white was higher than those of lysozyme and duck egg white. Pyrosequencing results revealed clear differences between the microbiomes of mastitic and normal raw milk samples and revealed a slightly similar, but clearly different, composition of pathogens compared to that from the culture method. Thus, pyrosequencing may be useful for elucidating changes in microbiomes during mastitis progression and treatment. A chicken egg white and antibiotic combination may help with mastitis treatment; however, further studies are needed.
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