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1.
Epidemiologically unrelated non-typhoid Salmonella isolates from humans (n = 56) and animal origin (n = 241, from faeces, carcasses and meat) in Vietnam were investigated. Salmonella Typhimurium, S. Anatum, S. Weltevreden, S. Emek, and S. Rissen were the most prevalent serovars. S. Typhimurium phage type 90 was predominant among S. Typhimurium isolates. The serotype and phage type distribution of the Salmonella isolates was different from that in Europe and America. Many sero- and phage types found in humans were also found in cattle, pigs, and poultry suggesting that food producing animals are an important source of human non-typhoid Salmonella infection in Vietnam.  相似文献   

2.
1. We analysed Salmonella isolates by conventional sero- and phage-typing, as well as by molecular techniques within the broiler production chain in two integrated companies. The most prevalent serovars were selected for genetic fingerprinting. 2. Isolates were first screened by plasmid profiling; subsequently, the most common plasmid types within the prevalent zoonotic serovars (enteritidis and typhimurium) and S. agama were further characterised by PstI-SphI ribotyping, and XbaI pulsed field gel electrophoresis (PFGE). 3. Salmonella binza, S. kedougou, and S. 4,12:d:- were endemic in the feed mills over long periods of time, and a variety of plasmid types for each of the serovars were found in the premises. 4. A similar situation was found with S. binza and S. senftenberg within the hatchery in company B. The Salmonella serovars which were resident in those locations were also the ones most widely distributed throughout the broiler flocks. 5. Plasmid profiling was useful to subdivide clusters of isolates within serovars, but for each serovar a high percentage (36 to 79%) of the isolates tested fall within a prevalent plasmid type. 6. A more detailed genetic analysis of the isolates by a multiple typing approach allowed for further strain differentiation, and allowed some epidemiological conclusions to be drawn.  相似文献   

3.
During 2000-2002 the National Veterinary Reference Laboratory for Salmonella (NRL-Salm) in Germany typed 11,911 isolates from animals, food, feed and the environment. All of them were tested for their susceptibility to 17 anti-microbial agents. Sixty-three per cent of all isolates were resistant and 40% were multiresistant (resistant against more than one anti-microbial). This general resistance level was strongly influenced by those specific serotypes which dominate the Salmonella epidemiology in Germany. Salmonella Typhimurium DT104 isolates from pig and cattle, and their resulting food products, were multiresistant in 98 and 94% of the cases respectively. During the period 2000-2003 an increasing quinolone resistance especially in Salmonella isolates from poultry and poultry meat (to 26%) and in S. Paratyphi B D-tartrate positive isolates (to 64%) could be observed. This increase was accompanied by a shift towards higher minimal inhibitory concentrations for ciprofloxacin.  相似文献   

4.
Salmonella isolates (n = 209) obtained from food animals and foods in Alberta during 1996 through 1999 were tested for sensitivity to 17 antimicrobials. Of the 3553 antimicrobial susceptibility tests on Salmonella isolates, 11.8% were positive for resistance. These isolates were commonly resistant to tetracycline (35.4%), streptomycin (32.5%), sulfamethoxazole (28.7%), ticarcillin (27.3%), and ampicillin (26.8%). Resistance to at least 1 antimicrobial was observed in 112 isolates (53.6%). Salmonella Typhimurium, S. Typhimurium var. Copenhagen, and S. Heidelberg were the most common serovars among isolates resistant to individual antimicrobials and multiple antimicrobials. The most common profile of multiple-antimicrobial resistance was that which included resistance to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, tetracycline, and ticarcillin. The proportions of isolates that were resistant to antimicrobials were greater among bovine isolates of Salmonella than among poultry isolates, and this difference was greater among isolates from veterinary diagnostic sources than among those from monitoring sources.  相似文献   

5.
The present report deals with Salmonella strains received at the German National Reference Laboratory for Salmonella (NRL-Salm) for routine diagnostic in the year 2009. Hence, the working group continues the previous report from Friedrich et al. (2010) about the documentation on the serovar distribution of Salmonella received at the NRL-Salm in the years 2004-2008. As in the recent years, most of the Salmonella strains originated from livestock and food. In the year 2009 the NRL-Salm received 4765 isolates, most of them (85,1 %) were routine diagnostic. Salmonella ser. Typhimurium, its monophasic variant S. enterica subspecies enterica serovar 1,4,[5],12:i:- and Salmonella ser. Enteritidis were the most prevalent serovars. The number of S. enterica subsp. enterica serovar 1,4,[5],12:i:- isolates increased in 2009, in comparison to the years 2004-2008, and became the second most prevalent serovar serotyped at the NRL-Salm.  相似文献   

6.
The aim of the present study was to determine the bacteriological prevalence of subclinical non-typhi Salmonella infections in zoo animals and to determine the most frequently isolated serovars of the bacteria. A total of 267 samples were analyzed, including fecal samples from zoo animals and rodents, insects (Musca domestica and Periplaneta americana) and samples of the zoo animal's food. Salmonella was detected in 11.6% of the samples analyzed. Characterization of the isolates was performed with serotyping and pulsed-field gel electrophoresis. The following serovars were isolated: S. San Diego, S. Oranienburg, S. Weltevreden, S. Braenderup, S. Derby, S. 6,7, H:en x:- and S. 3,10, H:r:-. The isolates showed seven pulsed-field gel electrophoresis patterns with a Jaccard coefficient ?0.75 indicating a possible common origin. The prevalence of asymptomatic infections caused by Salmonella spp. in zoo animals was high. These findings demonstrate the diversity of Salmonella serovars in several captive wild animal species.  相似文献   

7.
为了解上海市农贸市场肉鸽群体中沙门氏菌流行血清型和耐药情况,本试验于2011-2014年间从上海市各区农贸市场采集肉鸽新鲜粪便样本92份,用XLD平板和沙门氏菌属显色培养基分离疑似沙门氏菌,革兰氏染色镜检并进行生化试验,共获得沙门氏菌24株,分离率为26.1%。采用Kauffmann-White法和K-B纸片法对24株沙门氏菌进行血清型鉴定和16种抗生素的药敏试验。血清型鉴定显示,24株沙门氏菌可分为鼠伤寒（66.7%）、阿贡纳（25.0%）和科瓦利斯（8.3%）3种血清型。药敏试验结果显示,有75.0%（18株）的分离株表现出不同程度耐药,其中分离株对四环素和磺胺异唑耐药率最高,均达到62.5%,其次为链霉素（58.3%）、萘啶酸（50.0%）、氨苄西林（20.8%）。多重耐药菌株15株（62.5%）,耐4种抗菌药物的菌株最多,占16.7%（7株）。另外,分离菌株对头孢吡肟、头孢噻肟、头孢噻甲羧肟、亚胺培南、氧氟沙星等5种药物的敏感率为100.0%,对奥格门丁和环丙沙星有12.5%的中介敏感率。本研究结果表明,上海市肉鸽中沙门氏菌的携带率较高,且菌株多重耐药现象较严重,这为食品中沙门氏菌的防控工作带来较大的挑战和风险,肉鸽沙门氏菌的流行和耐药情况应值得密切关注。  相似文献   

8.
Two hundred faecal samples, collected from pigs at a Budapest abattoir, were examined for the presence of salmonellae. Ninety-six isolates, belonging to 7 different serotypes, were obtained. Salmonella derby (70.8%) was the most prevalent serotype. The other serotypes isolated were S. typhimurium (8.33%), S. bredeney (4.16%), S. agona (2.08%), S. infantis (9.22%), S. london (3.12%), and S. panama (2.08%). A modified rapid presumptive test to detect salmonellae in food and food ingredients was described by Hoben et al. (1973). This test medium was evaluated to determine its efficacy in detecting salmonellae in pig faecal samples. The test gave an efficiency of 88.67%. However, the incidence of false positive results was rather high (9.43%). The public health importance of the isolates obtained and the application of the rapid presumptive test at the farm level are discussed.  相似文献   

9.
The purpose of this study was to investigate the molecular types and antimicrobial resistance of Salmonella isolated from pigeon in Shanghai from 2011 to 2014. A total of 92 fecal samples were collected from markets. XLD plate and Salmonella chromogenic medium were used to isolate suspected Salmonella colonies, and then determined the number of Salmonella through gram staining and biochemical tests. Among them, 24(26.1%) were positive for Salmonella. Kauffmann-White method and the K-B method were used respectively for serotype identification and susceptibility testing. In result, serological identification showed that 24 isolates from pigeon could be divided into 3 serotypes including S.typhimurium (66.7%), S.agona (25.0%) and S.corvallis (8.3%). Drug susceptibility test showed that 75.0% of the isolates were resistant to one antibiotic at least. The highest level resistance were found for tetracycline as well as sulfisoxazole (62.5%), followed by streptomycin (58.3%), nalidixic acid (50.0%) and ampicillin (20.8%). Multi-drug resistant strains accounted for 62.5% (15), in which the largest number of strains (7, 16.7%) were resistant to four drugs. In addition, isolates were 100.0% susceptible to cefepime, cefotaxime, ceftazidime, imipenem and ofloxacin, but 12.5% were moderately sensitive to the amoxicillin/clavulanic acid and ciprofloxacin. The study showed that Salmonella had a high separation rate of pigeon in Shanghai farmers market and performed serious multidrug resistance, which would bring great challenges and risks to the prevention and control of Salmonella in food, so that the prevalence and drug resistance of Salmonella in pigeon deserved close attention.  相似文献   

10.
Salmonella continues to be a significant human health threat, and the objective of this study was to identify microorganisms with the potential to improve porcine food-safety through their antagonism of Salmonella. Anaerobic culture supernatants of 973 bacterial isolates from the gastrointestinal tract and feces of swine were screened for their capacity to inhibit the growth of Salmonella enterica serovar Typhimurium. Growth inhibition of 1000-fold or greater was observed from 16 isolates, and 16S rRNA sequencing identified the isolates as members of the genera Mitsuokella, Escherichia/Shigella, Anaerovibrio, Selenomonas, and Streptococcus. Four isolates were identified as Mitsuokella jalaludinii, and the mechanism of Salmonella Typhimurium growth inhibition by M. jalaludinii was further investigated. M. jalaludinii stationary phase culture supernatants were observed to significantly inhibit growth, and featured the production of lactic, succinic, and acetic acids. Aerobic and anaerobic S. Typhimurium growth was restored when the pH of the culture supernatants (pH 4.6) was increased to pH 6.8. However, S. Typhimurium growth in fermentation acid-free media was the same at pH 4.6 and pH 6.8 - indicating a synergistic effect between fermentation acid production and low pH as the cause of S. Typhimurium growth inhibition. Furthermore, exposure of S. Typhimurium to M. jalaludinii culture supernatants inhibited Salmonella invasion of HEp-2 cells by 10-fold. The results identify M. jalaludinii as a possible inhibitor of Salmonella growth and invasion in swine, and thus a potential probiotic capable of improving food safety.  相似文献   

11.
The present study was carried out to report the occurrence Salmonella spp., Salmonella Enteritidis, and Salmonella Typhimurium in chicken abattoirs. Samples of feces; feathers; scald, evisceration, and chiller water; and rinse water of non-eviscerated, eviscerated, and chilled carcass were collected from six chicken abattoirs. Salmonella isolates were identified by a multiplex-PCR using three sets of primers targeting the invA, pefA, and sefA gene sequences from Salmonella spp., S. Typhimurium and S. Enteritidis, respectively. Salmonella spp. was detected in 10% (29/288) of the samples, whereas serovars Enteritidis and Typhimurium were identified in 62% (7/288), respectively. The results indicate the need to improve hygiene and sanitary standards in poultry slaughter lines, besides the education of food handlers and information to consumers.  相似文献   

12.
Salmonella pullorum is the cause of pullorum disease, which is characterized by white diarrhea and a high mortality rate in poultry. During the 1990s, the serologic "pullorum" test has occasionally failed to detect infected birds during the early stage of disease. To determine if any recent genetic changes have taken place in S. pullorum to account for poor seroconversion sometimes observed in infected flocks, S. pullorum from 1990s outbreaks and strains isolated prior to the 1980s were typed by random amplified polymorphic DNA (RAPD). Of 40 S. pullorum isolates typed by this method, eight distinct DNA patterns were identified with one of three RAPD polymerase chain reaction primers. Sixty-two percent of S. pullorum isolates shared the same RAPD DNA pattern, and a major proportion of these strains were from recent flock infections. The RAPD patterns for S. pullorum were clearly distinct from the avian Salmonella group B isolates included in this analysis. The distribution of Salmonella virulence genes among avian Salmonella isolates was also examined. Eighty-five percent of the S. pullorum isolates had both the virulence plasmid gene, spvB, and the invasion gene, invA, with the same percentage positive for the Salmonella enteriditis fimbrial gene, sef. However, significant variability was observed among S. pullorum in their ability to invade avian epithelial cells, despite the presence of the Salmonella invasion gene in these isolates.  相似文献   

13.
OBJECTIVE: To investigate Salmonella enterica infections at a Greyhound breeding facility. DESIGN: Cross-sectional study. ANIMAL AND SAMPLE POPULATIONS: 138 adult and juvenile dogs and S. enterica isolates recovered from the dogs and their environment. PROCEDURES: The investigation was conducted at the request of a Greyhound breeder. Observations regarding the environment and population of dogs were recorded. Fecal, food, and environmental specimens were collected and submitted for Salmonella culture. Isolates were serotyped and tested for susceptibility to 16 antimicrobials. Isolates underwent genetic analyses by use of pulsed-field gel electrophoresis and ribotyping. RESULTS: S. enterica was recovered from 88 of 133 (66%) samples of all types and from 57 of 61 (93%) fecal samples. Eighty-three (94.3%) of the isolates were serotype Newport, 77 (87.5%) of which had identical resistance phenotypes. Genetic evaluations suggested that several strains of S. enterica existed at the facility, but there was a high degree of relatedness among many of the Newport isolates. Multiple strains of Salmonella enterica serotype Newport were recovered from raw meat fed on 1 day. CONCLUSIONS AND CLINICAL RELEVANCE: S. enterica infections and environmental contamination were common at this facility. A portion of the Salmonella strains detected on the premises was likely introduced via raw meat that was the primary dietary constituent. Some strains appeared to be widely disseminated in the population. Feeding meat that had not been cooked properly, particularly meat classified as unfit for human consumption, likely contributed to the infections in these dogs.  相似文献   

14.
Fecal samples were collected from 200 feeder-calves on farms in Tennessee, after assembly at a Tennessee auction market, and after transport to a Texas feedyard. A final fecal sample was collected from each calf after 30 days of feedyard confinement. The fecal samples were cultured for the presence of Salmonella spp. Salmonella isolates were serotyped and antimicrobial drug-resistance patterns determined. The number of calves fecal culture-positive for Salmonella spp increased from 0 on the Tennessee farms and auction market to 3/200 (1.5%) at entry into the Texas feedyard, and 16/200 (8%) after 30 days of feedyard confinement. Salmonella serotypes isolated and the number of isolates of each serotype were S reading (8), S cerro (4), S newbrunswick (3), S anatum (2), and S typhimurium (copenhagen; 2). All Salmonella isolates were resistant to 5 or more of 13 antimicrobial drugs tested. Salmonella reading isolates were resistant to 10 or 11 of 13 antimicrobial drugs. The results indicated that the calves could have been infected with Salmonella spp prior to or during the course of the study, and that marketing stress as they moved from farm through feedyard may have induced fecal excretion of salmonellae. In addition, the pattern of antimicrobial drug resistance in the Salmonella isolates was broad.  相似文献   

15.
Prevalence and persistence of Salmonella in broiler chicken flocks.   总被引：2，自引：0，他引：2  
Cecal contents of 2,345 broiler chickens consisting of 28 flocks originated from 12 farms were examined for the prevalence of Salmonella to know the actual status of infection with Salmonella in the chicken flocks. Salmonella was isolated from 336 (14.3%) samples. From these isolates, eight serovars were identified. Of the 336 Salmonella isolates, 242 (72.0%) were serotyped as S. Blockley, 60 (17.9%) S. Hadar, 15 (4.5%) S. Bredeney, nine (2.7%) S. Schwarzengrund, four (1.2%) S. Anatum, three (0.9%) S. Enteritidis, two (0.6%) S. Ohio, and one (0.3%) S. Livingstone. The same serovars of Salmonella were repeatedly found in the chickens from the same farms. S. Typhimurium and S. Enteritidis were detected in pooled broken eggshell samples collected from the hatchery. Analysis of plasmid profiles revealed 11 patterns of S. Blockley and seven patterns of S. Hadar. Strains of the same plasmid profiles of S. Blockley were isolated repeatedly from the same farm over one year after the first isolation.  相似文献   

16.
A genetic probe encoding a virulence gene from Salmonella typhimurium was useful in the detection of Salmonella from feces during an outbreak of salmonellosis at a local dairy. A 3.2-kb BamHI restriction endonuclease fragment of the S. typhimurium virulence plasmid, pStSR100, has been useful as a DNA probe for both detection of Salmonella sp. and characterization of virulence plasmids from numerous field isolates. This virA probe hybridizes to a highly conserved gene carried on the large virulence plasmids of invasive Salmonella isolates. Colony blots prepared from feces directly plated onto MaConkey's agar failed to detect low numbers of Salmonella sp. However, hybridization of the VirA probe to vacuum blots or colony blots prepared from feces in tetrathionate enrichment broth incubated for 16 hours at 37 C was effective for detecting Salmonella sp. and resulted in an 85.9% correlation with culture results. The probe also demonstrated the highly conserved nature (96%) of the virulence gene among S. cholerae-suis isolate plasmids detected using Southern blot analysis.  相似文献   

17.
Salmonella belonging to 47 serotypes was isolated from animals at the University of California Veterinary Medical Teaching Hospital during the years 1974 to 1983. Salmonella belonging to 12 serotypes accounted for 89% of the 725 isolates. Salmonella typhimurium (including var copenhagen) was the most commonly isolated serotype, but during 1981 to 1983, S krefeld and S saint-paul were predominant. Certain serotypes seemed to be isolated more frequently from extraintestinal sources (S typhi-suis, S dublin). Although resistance to ampicillin, kanamycin, neomycin, streptomycin, and sulfonamides was common (greater than 60% of the isolates were resistant), resistance to chloramphenicol, gentamicin, and trimethoprim-sulfonamides was infrequent, except for isolates of S krefeld and S saint-paul.  相似文献   

18.
为了解食品动物源沙门氏菌质粒介导喹诺酮类耐药性(Plasmid-mediated quinolone resistance,PMQR),采用微量肉汤稀释法和PCR方法,检测了316株食品动物源沙门氏菌对20种抗菌药物的敏感性,以及菌株中PMQR基因的携带率.结果显示:316株沙门氏菌对20种抗菌药物呈不同程度的耐药性,95.57％菌株为多重耐药菌;316株菌中未检出qnrA、qnrC、qnrD、qnrS和qepA基因,7.91％菌株检出qnrB基因,15.19％菌株检出aac(6 ′ )-Ib-cr基因,7.91％菌株检出oqxA基因,8.86％菌株检出oqxB基因,这是首次在沙门氏菌中发现oqxAB基因;98.11％PMQR阳性菌同时携带2种及以上的耐药基因,呈8～17耐的多重耐药性,其中以qnrB和aac(6′)-Ibcr基因型为主;53株PMQR阳性菌分属于5种不同的基因型,耐药表型或耐药基因型不同的菌株却有相同的PFGE谱型.本次检测的316株食品动物源沙门氏菌耐药较为严重;菌株主要携带qnrB、aac(6 ′ )-Ib-cr及oqxAB基因;不同来源菌株存在同一耐药克隆株的流行.  相似文献   

19.
OBJECTIVE: To determine whether Salmonella spp could be isolated from the environment of free stall dairies in Wisconsin without any history of clinical salmonellosis and determine the serotype and antimicrobial susceptibility of any Salmonella isolates recovered from the environment. DESIGN: Cross-sectional study. STUDY POPULATION: 20 free stall dairies with no history of clinical salmonellosis. PROCEDURES: Dairy owners completed a questionnaire regarding management and production practices. Multiple swab samples were obtained from throughout the free stall facilities and submitted for bacterial culture for Salmonella spp. Odds ratios were calculated to compare herd-level risk factors between dairies from which Salmonella organisms were isolated and herds from which Salmonella organisms were not isolated. RESULTS: Salmonella organisms were isolated from 9 of the 20 (45%) dairies. Salmonella serotype Meleagridis was isolated from 4 dairies, S. Meleagridis and S. Kentucky were isolated from 2 dairies, S. Meleagridis and S. Cyprus were isolated from 1 dairy, S. Cerro was isolated from 1 dairy, and S. Corvallis was isolated from 1 dairy. All isolates were susceptible to all antimicrobial agents tested. None of the potential risk factors analyzed demonstrated a significant association with an increased likelihood of isolating Salmonella spp. CONCLUSIONS AND CLINICAL RELEVANCE: Environmental Salmonella contamination was demonstrated on free stall dairies with no history of clinical salmonellosis.  相似文献   

20.
From November 2000 to July 2002, 112 fecal samples from pet reptiles, including 18 turtles, 71 lizards and 23 snakes, sold at a pet shop were examined for the prevalence of Salmonella spp. in Japan. Salmonella spp. were isolated from 83 (74.1%) of 112 samples, and a total of 112 Salmonella isolates were identified as subspecies I to IV. The majority of isolates (62.5%) belonged to subspecies I and 54 isolates could be identified as any of 28 serovars. The predominant serovars were found to be S. Bardo, S. Newport and S. Panama, which cause human salmonellosis. These results indicate that pet reptiles may be a potential infectious source of human salmonellosis in Japan.  相似文献   

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