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1.
新疆绵羊及其环境中李氏杆菌的生态分布多样性调查   总被引：1，自引：0，他引：1  
对新疆健康绵羊及其相关环境如青贮饲料、饮水、土壤、鸟粪中李氏杆菌(Listeria)种群采用改良国标法(4789.30-2010)进行生态分布多样性调查,并对分离的单核细胞增多性李氏杆菌(L.monocytogenes)采用PCR方法进行溶血素基因(hly)和血清型检测。结果:514份样本中,共检出阳性样本26份,平均阳性率为5.1%,其中羊体分离率为6.2%(22/353),饮水分离率为33%(2/6),鸟粪分离率为3.0%(2/67),其余样本均为阴性;26份阳性样品中,检出单核细胞增多性李氏杆菌5株,塞氏李氏杆菌(L.seeligeries)21株,且5株单核细胞增多性李氏杆菌均检出溶血素基因,血清型为1/2a。  相似文献   

2.
At the Danish Veterinary Laboratory Streptococcus suis infections in pigs were diagnosed in 114 cases in 1995 and in 151 cases in 1996. Isolates were serotyped using specific antisera against type 1 through 28 and a total of 67 cases from 1995 and 113 cases in 1996 were tested for resistance to 11 antimicrobial agents. The majority of cases were lung diseases (57%), followed by septicaemia (16%), meningitis (15%) and endocarditis (8%). Almost 96% of the isolates could be typed using the 28 antisera. The most common serotype was serotype 2 (29%), followed by serotype 7 (17%), and serotypes 3, 4 and 8 (9–10%). The remaining serotypes were observed in frequencies of less than 5%. Serotype 7 was more commonly isolated from septicaemia than the other serotypes. Serotype 2 was more commonly isolated from pigs older than 4 weeks compared to the other serotypes. Most isolates were susceptible to amoxycillin+clavulanate, ampicillin, ceftiofur, enrofloxacin, penicillin, spectinomycin, tiamulin and trimethoprim+sulphadiazine. A high frequency (>30%) of resistance to tetracycline was observed. Among isolates of serotype 2, 9.7% were resistant to lincomycin and 12.9% to spiramycin. Among other serotypes 56.8% were resistant to lincomycin and spiramycin. The differences in susceptibility between isolates of serotype 2 and the other serotypes were statistically significant. Compared to a previous Danish study the distribution of serotypes of S. suis causing infections among pigs in Denmark has changed during the last 15 years.  相似文献   

3.
A survey using tube agglutination test was conducted to determine the antibody prevalence to Listeria monocytogenes serotypes 1/2a, 1/2b, 1/2c, 3a and 4b in 1,190 serum samples of 8 animals species from various sources in Kano and Kaduna states of Nigeria. Following absorption with Staphylococcus aureus antigen to remove cross-reacting agglutinins, 52 (68.4 p. 100) of the horse samples were positive. Twenty-six (36.1 p. 100) pig, 52 (20.8 p. 100) cattle, 50 (20.0 p. 100) goat, 20 (20.0 p. 100) dog, serum samples were also positive. Free-ranging chickens had an antibody prevalence of 18 (32.1 p. 100) while those intensively managed had 3 (6.8 p. 100), a difference found to be statistically significant (P less than or equal to 0.01; X2). Sheep sera collected from Zaria abattoir had a prevalence of 30 (14.7 p. 100) while those from Ahmadu Bello University, Veterinary Teaching Hospital had 6 (13.0 p. 100) prevalence. The prevalence in camel was 4 (4.3 p. 100). Overall, of the 1,190 serum samples tested, 26 (21.9 p. 100) were sero-positive for L. monocytogenes agglutinins. Each species of animal tested for L. monocytogenes was positive for all five serotypes, except camel which was negative for serotype 3a. Fourty-four (53.0 p. 100) samples were positive at a titre of greater than or equal to 480 for serotypes 1/2a, 60 (58.3 p. 100) for 1/2b, 57 (52.3 p. 100) for 1/2c, 7 (13.7 p. 100) for 3a and 23 (39.0 p. 100) for 4b. It is concluded that L. monocytogenes infection is widespread in domestic animals in Nigeria.  相似文献   

4.
Between 1991 and 1993, the intestinal contents and feces of wild animals in Japan were examined for the presence of Listeria. The wild animals examined included 623 mammals (11 species) and 996 birds (18 species). Listeria species were isolated from 38 (6.1%) of the 623 mammalian samples and 133 (13.4%) of 996 bird samples. The highest incidence of Listeria in the mammals was found in Japanese monkeys (20.0%) and that in birds was found in crows (43.2%). The incidence of Listeria in Japanese monkeys varied from 0 to 40.0% depending on the capture area. L. monocytogenes was isolated from II of these positive samples. Serovars 1/2a and 4b predominated in eight serotyped L. monocytogenes isolates.  相似文献   

5.
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6.
Retail pork (38 samples), cod (10 samples) and herring (10 samples) were obtained from 12 stores in the area of Lund in southern Sweden during September and October 1990. Erysipelothrix rhusiopathiae was isolated from 50% of the pork samples, 60% of the cod samples and from 30% of the samples from herring. Serotype 2 dominated on retail pork as well as on fish samples constituting 53% of the pork isolates (10 strains) and 33% of the cod isolates (2 strains). All E. rhusiopathiae isolates originating from herring were serotype 2 (3 strains). Serotypes 1b, 6, and 8 were isolated from retail pork only (6, 2 and 1 strains, respectively). Serotype 5 was isolated from cod only (3 strains) and so was serotype 9 (1 strain). The public health hazards with the occurrence of virulent strains of Erysipelothrix rhusiopathiae in retail pork and fish are discussed.  相似文献   

7.
We attempted to isolate Listeria monocytogenes from skin, contents of large intestines and carcasses of cattle introduced to a slaughterhouse in order to identify source of contamination for this pathogen. Sixty skin samples, 60 samples of the contents of large intestines and 30 carcass samples were colleted in June, August and November 2003 for use in this study. Listeria spp. and L. monocytogenes were isolated from 30 (50%) and 3 (5%) of the cattle skin samples, respectively. However, no Listeria spp., including L. monocytogenes, were isolated from intestinal contents or carcasses. Seven isolates were obtained, of which five and two strains were serotypes 1/2a and 1/2b, respectively. Genetic analysis suggested that there was persistent inhabitation of the pathogen around the area investigated in this study.  相似文献   

8.
A total of 1,705 fecal specimens or ileo-cecal contents of cattle, pigs, dogs, cats, chicken and rats were submitted for the isolation of Listeria monocytogenes by the use of the combination of Oxford-LPM agar plates after the cold enrichment in PBS at 4 degrees C for 4-6 weeks. Prevalence of L. monocytogenes was found to be 1.9% in cattle, 0.6% in pigs, 0.9% in dogs and 6.5% in rats. However, none of L. monocytogenes was isolated from chicken or cats. Among 26 isolates of L. monocytogenes, 13 strains (50%) were classified into types 1/2a (3 strains), 1/2b (5 strains) and 4b (5 strains) and were often associated with human listeriosis. The majority of the Listeria spp. other than L. monocytogenes isolated from these animals was found to be L. innocua.  相似文献   

9.
In order to compare the plate count method for quantitating Listeria, as published in the "Official Collection of Testing Methods" in section 35 LMBG (L. 00.00-22), to an MPN-method for Listeria based on the same mediums, these two detection methods for Listeria were tested in three sets of experiments and a routine sample status evaluation. A pure broth culture of L. monocytogenes, artificially with L. monocytogenes contaminated ground meat, artificially contaminated and cold stored ground meat as well as 77 ground beef samples from Berlin retail food stores were used in the four trials. The detection limit of the MPN-method is about 66% lower than the plate count method allowing detection of a clearly greater number of Listeria-positive samples from naturally contaminated ground meat. The MPN-method yielded more Listeria spp.-positive samples (rel. 43%) and more L. monocytogenes-positive samples (rel. 21%) versus the colony count method based on the results from the field trial using ground beef samples from retail food stores in Berlin. Nevertheless the standardized colony count method is preferred over the MPN-method for routine use because of its slightly higher productivity and much smaller variation in the results. However, the MPN-method is preferable for epidemiological studies because of the significance of the lower detection level. The random sampling evaluation of ground beef from retail stores indicated that 39% of the samples were Listeria spp.-positive and 31% were L. monocytogenes-positive when using the colony count method. A total of 56% of the meat samples were found to be Listeria spp.-positive and 38% L. monocytogenes-positive when the MPN-method was used. Population levels ranged from 10 to 580 cfu/g (Listeria spp.-positive samples) and from 10 to 270 cfu/g (L. monocytogenes-positive samples) for the colony count method. The MPN-method yielded population levels of 3.6 to 930 MPN/g for Listeria spp.-positive samples and 3.6 to 150 MPN/g for L. monocytogenes-positive samples. L. monocytogenes strains isolated using the colony count method belonged to the following serovars: 1/2a (46%), 1/2b (13%), 1/2c (33%), 3b (4%) and 4c (4%). A similar serovar isolation pattern was found for L. monocytogenes-positive MPN-tubes. The most common serotype was 1/2a (43%), followed by 1/2c (32%) and 1/2b (14%). The serotypes 3c, 4b and 4c were all isolated 4% of the time.  相似文献   

10.
The aim of this study was to determine the simultaneous occurence of Salmonella spp., L. monocytogenes, verotoxigenic E. coli (VTEC), and Campylobacter spp. in slaughtered cattle and in beef meat subjected for human consumption. A total of 406 bovine hides and 406 corresponding carcasses were used to collect the samples with a swab method after exsanguination and evisceration of animals, respectively. Furthermore, 362 beef meat samples were purchased in local retail shops over the same period of time as for the bovine samples. Food-borne bacterial pathogens were identified with standard ISO methods with some modification by the use of PCR for VTEC. The isolated bacteria were then molecularly speciated (Campylobacter), serotyped (L. monocytogenes) and characterized for the presence of several virulence marker genes (VTEC and Campylobacter). It was found that 49 hide (12.1%) and 3 (0.7%) carcass samples were contaminated with more than one bacterial pathogen tested. Most of the hides were positive for Campylobacter spp. and VTEC (27 samples) and Campylobacter spp. together with L. monocytogenes (12 samples). Eight bovine hides contained L. monocytogenes and VTEC while L. monocytogenes and Salmonella spp. were detected in one sample. Furthermore, 3 pathogens (Campylobacter spp., L. monocytogenes and VTEC) were simultaneously identified in one bovine hide tested. In case of bovine carcasses 2 samples contained Campylobacter spp. and VTEC whereas one carcass was positive for L. monocytogenes and VTEC. On the other hand, 10 out of 362 (2.8%) minced beef samples were contaminated with at least two pathogens tested. The majority of these samples were contaminated with L. monocytogenes and Salmonella spp. (6 samples). It was noticed that equal number of C. jejuni and C. coli were found, irrespective of the origin of the samples. Most of the strains possessed more than one pathogenic factor as identified by PCR. Molecular serotyping of L. monocytogenes revealed that the majority of the isolates (27 out of 31; 87.1%) belonged to 1/2a serogroup. It was found that most of the VTEC isolates possessed the Shiga toxin stx2 gene (12 strains) whereas only 2 strains were str1-positive. The eneterohemolysin and intimin markers were identified only in 7 and 2 isolates, respectively. PCR analysis revealed that 4 VTEC belonged to O91 serogroup, 2 strains were O145 and 1 isolate was identified as O113. None of the VTEC detected in the study was O157 serogroup.  相似文献   

11.
Two juvenile scimitar-horned oryx (Oryx dammah) at the Wild Animal Park Planckendael died from acute septicemia caused by Listeria monocytogenes serovar 4b. Subsequently, Listeria spp. were isolated from the feces, food, and environment of seven antelope species and examined using a two-stage enrichment procedure in Fraser Broth, followed by isolation on PALCAM agar. A total of 40/170 samples (23.5%) was positive for Listeria spp. No organisms were cultured in 83/170 samples (48.8%), and 47 samples (27.6%) were overgrown with Bacillus spp. Nonpathogenic Listeria spp. were isolated from 16/70 fecal samples, 22/40 soil samples, and 2/60 feed samples. Listeria monocytogenes serovar 1/2b was isolated from two soil samples collected in the enclosure of the scimitar-horned oryx.  相似文献   

12.
Qualitative and quantitative contamination of ready-to-eat food-stuffs with the pathogen Listeria monocytogenes was studied in 1586 samples collected from 103 supermarkets (n = 946) and 61 households (n = 640) in Vienna, Austria. Seventeen groups of ready-to-eat foods were classified into three risk categories for contamination (CP1-CP3). Three to four samples were randomly collected at the retail level from each CP. Regarding the households, the sampling procedure was started with food items of CP1, and if not available, was continued with sampling of food items of CP2 and finally of CP3. Additionally, 184 environmental samples (swabs from the kitchen area, dust samples from the vacuum cleaner) and faecal samples (household members and pet animals) were included. One-hundred and twenty-four (13.1%) and 45 (4.8%) samples out of 946 food samples collected from food retailers tested positive for Listeria spp. and L. monocytogenes, respectively, with five smoked fish samples exceeding the tolerated limit of 100 CFU/g food. Food-stuffs associated with the highest risk of contamination were twice as frequently contaminated with L. monocytogenes as food-stuffs associated with a medium risk of contamination. Products showing the highest contamination rate were fish and seafood (19.4%), followed by raw meat sausages (6.3%), soft cheese (5.5%) and cooked meat products/patés (4.5%). The overall contamination rate of foods collected at the household level was more than two times lower. Only 5.6% and 1.7% of 640 food-stuffs analysed tested positive for Listeria spp. and L. monocytogenes, respectively. However, CP1 foods were rarely collected. Pulsed-field gel electrophoresis (PFGE) typing of the collected L. monocytogenes isolates revealed a high degree of diversity between the isolates, with some exceptions. PFGE typing of isolates harvested from green-veined cheese revealed a match among strains, although the manufacturer seemed to be distinguishable. Typing of household strains revealed an epidemiological link within one family. In this case, food-stuffs and the kitchen environment were contaminated by an indistinguishable isolate. In addition, the same isolate was collected from a pooled faecal sample of the household members suggesting that consumption of even low contaminated food items (<100 CFU/g) results in Listeria shedding after the passage through the gut.  相似文献   

13.
A synthetic deoxyribonucleotide probe for virulent Listeria monocytogenes, designated ADO7, was evaluated for its ability to identify restriction fragments of L. monocytogenes with nucleic acid sequences homologous with the beta-hemolysin gene by Southern blot hybridization of clinical and food isolates. The synthetic probe hybridized with three restriction fragments (approximately 1.1, 0.86, and 0.76 kb) of the serotype 1/2A isolates. Southern blot hybridization of the serogroup 4B isolates indicated that the nucleic acid sequences homologous with the beta-hemolysin gene probe were limited to a single restriction fragment of approximately 1 kb.  相似文献   

14.
This is the first report of molecular characterization of US erysipelas field isolates and vaccine strains of Erysipelothrix rhusiopathiae by pulsed-field gel electrophoresis (PFGE). Erysipelas in pigs is mainly caused by E. rhusiopathiae serotypes 1a, 1b, and 2. In 2001, erysipelas reemerged as a clinical problem in pigs in the midwestern United States. In this work 90 erysipelas isolates (58 recent and 28 archived field isolates as well as 4 live-vaccine strains) were genetically characterized. Because of the limited availability of antiserum, 74/90 isolates (44/58 recent isolates) were serotyped. The serotype of the majority (79.6%) of the 44 recent isolates tested was determined to be 1a, 13.6% were serotype 1b, and 6.8% of recent isolates were serologically untypeable. Among all 90 isolates, 23 different PFGE patterns were identified. There were 43 isolates identified as serotype 1a with 4 genetic patterns: 38/43, 1A(I); 3/43, 1A(III); 1/43, 1B(V); and 1/43, 3B. Sixteen serotype 1b isolates had 11 unique genetic patterns: 4/16 were genotype 1B(III), 2/16 were genotype 3A(I), and 1/16 was in genotype groups 1A(V), 1A(VI), 1A(VII), 1B(I), 1B(IV), 1B(VII), 2, 4, and 5. Six genetic patterns were distinguished among the 10 serotype 2 isolates: 1A(IV) (1/10), 1A(V) (1/10), 1B(VI) (1/10), 2 (4/10), 7 (1/10), and 8 (2/8). Erysipelas vaccine strains (modified live) were similar to each other but different from current field strains, sharing 78.6% identity with the most prevalent genotype 1A(I) based on the PFGE-SmaI pattern. Compared with serotyping, PFGE genotyping is a more distinguishing technique, easy to perform and not dependent on the limited availability of antiserum.  相似文献   

15.
An outbreak of listeric meningo-encephalitis occurred in a population of 1800 fallow deer (Dama dama) in a park during the winter and early spring of 1985 to 1986. Listeriosis was diagnosed in 41 of 42 fallow deer that showed the typical central nervous system signs of circling disease or were found dead. The diagnosis was verified by bacteriological examination of the brains of 35 animals. In five of the seven remaining cases listeriosis was diagnosed by histological examination, and in one animal by clinical signs alone. Listeria monocytogenes was isolated in three of 23 soil samples taken from the park. In addition, L monocytogenes was isolated from the intestinal contents of apparently normal fallow deer. Fifty isolates from animals and soil were serotyped and all of them belonged to serovar 4b except one from brain (serovar 1/2b) and three from intestinal contents (serovar 1/2a). In phage typing of 54 isolates, the 35 isolates from the brain and spleen of diseased animals belonged to the same lysovar, as did most isolates from other sources, but strains from intestinal contents belonged to three other phage types. No external source of L monocytogenes was demonstrated in the outbreak and stress due to the poor beech-mast crop, an increased stocking rate and a sudden change in the weather are suspected as predisposing factors.  相似文献   

16.
This study surveys 2,593,348 cattle slaughtered between 1996 and 2000, and further investigates 571 (0.02%) animals found to have tuberculous lesions. Culture of 346 randomly selected tissue samples from animals younger (n = 215) and older (n = 131) than 2 years, isolated mycobacteria from 91 animals (26.3%). These included 74 Mycobacterium avium subsp. avium isolates of IS901+ and IS1245+ genotype and serotype 2, 13M. avium subsp. hominissuis isolates of IS901- and IS1245+ genotype and serotypes 8 (n = 7) and 4 (n = 6), two M. chelonae, one M. avium subsp. paratuberculosis (RFLP type B-C1), and one M. terrae. Culture of mesenteric lymph node samples obtained 66 isolates of M. avium complex (MAC) and four isolates of other mycobacterial species. M. bovis was significantly absent from all samples. Mycobacteria were more frequently (P = 0.01) isolated from tissues of animals under 2 years (34.4%) than animals over 2 years (13.0%). IS901 and IS1245 RFLP methods were used to type 17 randomly selected MAC isolates, virulent after intramuscular inoculation of pullets, from 17 different cattle herds. These revealed 11 distinct IS901 RFLP types and three IS1245 RFLP profiles. Polyclonal infection of individual animals was detected by IS901/IS1245 typing in 2 of the 17 selected isolates.  相似文献   

17.
This study was undertaken to determine the prevalence, capsular serotype, and antimicrobial susceptibility of Streptococcus suis isolated from slaughter pigs. Capsular serotype and antimicrobial susceptibility were determined by coagglutination test and agar dilution minimum inhibitory concentration, respectively. Streptococcus suis was isolated from 55 of the 406 palatine tonsillar samples tested (13.8%) and 14 of the 29 sampled herds (48.3%). Of the 55 isolates recovered from slaughter pigs, 26 (47.3%) were untypeable. Of the remaining 29 isolates, capsular serotypes 9 (9 isolates) and 16 (4 isolates) were the most common, followed by capsular serotypes 4 (3 isolates) and 7 (3 isolates). Every capsulated isolate was typeable and no palatine tonsillar sample yielded more than one serotype. Most of isolates were susceptible to low concentrations (MIC90) of amoxicillin (2 microg/mL), ceftiofur (1 microg/mL), and penicillin (1 microg/mL). No correlation was found between antimicrobial susceptibility and capsular serotype.  相似文献   

18.
In the autumn of 1995 the first outbreaks of enterohemorrhagic Escherichia coli O157:H7 including ca 100 human cases were reported in Sweden. From outbreaks in other countries it is known that cattle may carry these bacteria and in many cases is the source of infection. Therefore, the present study was performed to survey the Swedish bovine population for the presence of verotoxin-producing E. coli (VTEC) of serotype O157:H7. Individual faecal samples were collected at the 16 main Swedish abattoirs from April 1996 to August 1997. Of 3071 faecal samples, VTEC O157 were found in 37 samples indicating a prevalence of 1.2% (CI95% 0.8-1.6). All 37 isolates carried genes encoding for verotoxin (VTI and/or VT2), intimin, EHEC-haemolysin and flagellin H7 as determined by PCR. Another 3 strains were of serotype O157:H7 but did not produce verotoxins. The 37 VTEC O157:H7 strains were further characterised by phage typing and pulsed-field gel electrophoresis. The results clearly show that VTEC O157:H7 is established in the Swedish bovine population and indicate that the prevalence of cattle carrying VTEC O157:H7 is correlated to the overall geographical distribution of cattle in Sweden. Results of this study have formed the basis for specific measures recommended to Swedish cattle farmers, and furthermore, a permanent monitoring programme was launched for VTEC O157:H7 in Swedish cattle at slaughter.  相似文献   

19.
为鉴定分离自新疆北疆绵羊单核细胞增生李斯特氏菌,本研究采用多重PCR方法,鉴定来自病发地区部分羊场的发病绵羊、健康绵羊、羊舍环境和乌鸦粪分离的30株李斯特氏菌分离株的8株单核细胞增生李斯特氏菌分离株血清型。结果为4株发病绵羊株有3株鉴定为单核细胞增生李斯特氏菌,血清型为1/2a或4b,1株为非单核细胞增生李斯特氏菌;5株健康绵羊株血清型为1/2a;其余来自羊舍水源的3株、乌鸦粪的2株及健康绵羊16株为非单核细胞增生李斯特氏菌,表明来自发病绵羊、健康绵羊及参考菌株LM血清型之间具有相关性。  相似文献   

20.
Resistance to 16 antimicrobial agents was monitored in 109,125 Salmonella cultures isolated from animals, their environment and feedstuffs between 1988 and 1999. The sensitivity of the 6512 isolates of Salmonella enterica enterica serotype Dublin to all the antimicrobial agents tested varied from 98.2 per cent in 1997 to 99.7 per cent in 1990 and 1996. In contrast, among 28,053 isolates of Salmonella enterica enterica serotype Typhimurium, there was a marked decrease in their sensitivity to all the antimicrobial agents tested, from 57.4 per cent in 1992 to 7.6 per cent in 1995, owing to the widespread occurrence in farm animals of S Typhimurium isolates of the definitive type DT104, resistant to ampicillin, sulphonamides, streptomycin, chloramphenicol and tetracyclines, although the percentage of sensitive isolates increased to 18.4 per cent in 1999, when the incidence of DT104 had decreased. Some isolates of DT104 also showed an increase in resistance to potentiated sulphonamides (2.4 per cent in 1989 to 19.2 per cent in 1999) and nalidixic acid (0 per cent in 1992, 3.8 per cent in 1995 to a peak of 16.9 per cent in 1998). In 1996, 5.1 per cent of 1086 isolates of S Typhimurium from cattle and 35.9 per cent of 192 isolates of S Typhimurium from poultry showed resistance to nalidixic acid. Of the other 74,528 Salmonella isolates, the percentage of strains sensitive to all the antimicrobials tested decreased slightly from 88.2 per cent in 1988 to 70.6 per cent in 1996 and then increased slightly to 73.7 per cent in 1999. The commonest of these other Salmonella serotypes was Salmonella Enteritidis (20,982), which remained predominantly susceptible (ranging from 81.4 to 97.4 per cent) during the study period. Few isolates were resistant to commonly used veterinary antimicrobials, for example, furazolidone, the use of which was banned in 1990, and the aminoglycoside, apramycin.  相似文献   

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