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1.
A total of 314 clinical and non-clinical isolates of the genus Staphylococcus was tested for coagulase production and glucose and mannitol fermentation. The isolates were tested for thermonuclease production and agglutination by sera 17H and 61218, which were specific for human and canine S. aureus biotypes, respectively. All produced coagulase and fermented glucose. A majority fermented mannitol anaerobically except for the canine isolates. A majority of human isolates produced thermonuclease (64.3%) and most were agglutinated by serum 17H. There was good correlation between thermonuclease production and agglutination by serum 17H of human and bovine clinical isolates (86.6 and 80%, respectively). This was also true of clinical canine isolates agglutinated by serum 61218, of which 75% were thermonuclease-positive. Over half of canine isolates (52.8%) were thermonuclease-positive and most were agglutinated by serum 61218. Bovine and caprine isolates were 34.1 and 25% thermonuclease-positive, respectively, while ovine isolates were only 14.2% thermonuclease-positive. Isolates from these ruminant sources were also poorly agglutinated by either serum. It was concluded that a greater number of clinical human and canine biotypes of S. aureus produced thermonuclease than their non-clinical isolates, and that a majority of other animal isolates were negative for thermonuclease. Therefore, the thermonuclease test may not be very useful for confirming the animal origin of S. aureus isolates.  相似文献   

2.
Comparisons were made among rapid latex agglutination tests and conventional biochemical tests used to identify Streptococcus agalactiae and Staphylococcus aureus. Ninety-eight streptococci and 149 staphylococci isolated from bulk tank milk were tested. Sensitivity and specificity for the latex agglutination test used for identification of Str agalactiae were 97.6 and 98.2%, respectively. Sensitivity and specificity for the latex agglutination test used for identification of S aureus were 90.2 and 67.5%, respectively. Of 25 staphylococci considered false-positive by the latex agglutination test, 14 (56%) were considered tube coagulase-positive. Fifteen staphylococci considered false-positive by latex agglutination test had biotypes representative of S hyicus of S xylosus.  相似文献   

3.
Three rapid agglutination assays for the identification of Staphylococcus aureus Monostaph (Bionor A/S, Skien, Norway), Staphyslide-Test (BioMerieux, Lyon, France) and Staph-Rapid-Test (Roche, Basel, Switzerland), were compared. A total of 104 Gram-positive, catalase positive cocci were tested: Nineteen Staphylococcus reference strains comprising 15 spp. (4 strains were coagulase positive), and 7 Micrococcus reference strains comprising 4 spp.; 22 food isolates comprising 13 S. aureus, 8 coagulase positive Staphylococcus spp., and 1 Micrococcus sp.; 56 animal isolates comprising 11 S. aureus, 9 S. hyicus subsp. hyicus, 2 S. intermedius, 15 coagulase positive and 19 coagulase negative Staphylococcus spp. Totally 54 strains were coagulase positive. Considering agglutination of a coagulase positive strain as a correct identification, Monostaph, Staph-Rapid-Test, and Staphyslide-Test correctly identified 52 (96.3%), 47 (87.0%) and 48 (89.0%) of the coagulase positive staphylococci, respectively. Monostaph, Staph-Rapid-Test and Staphyslide-Test showed 1 (2.0%), 4 (8.0%) and 4 (8.0%) false positive reactions respectively. Monostaph, Staph-Rapid-Test and Staphyslide-Test gave 0 (0.0%), 6 (5.8%) and 7 (6.7%) non-interpretable reactions, respectively. Monostaph may be a good alternative to the tube-coagulase test for rapid and reliable identification of coagulase positive staphylococci from both food and veterinary sources. However, false negative reactions may occur with coagulase positive strains of S. hyicus subsp. hyicus and S. intermedius.  相似文献   

4.
Fifty-one coagulase-positive staphylococcal isolates from canine urinary calculi or from the urine of dogs with documented urolithiasis, and 17 coagulase-positive staphylococcal isolates from human beings and cattle were identified by a commercially available tray micromethod, as well as by conventional methods. Canine isolates had previously been classified as Staphylococcus aureus on the basis of a positive tube coagulase test. After 5 hours' incubation, the tray method identified all 51 canine urolithiasis isolates as S intermedius, rather than S aureus. All human and bovine isolates were identified as S aureus. Conventional methods supported these findings.  相似文献   

5.
Two hundred and ninety-three isolates of Staphylococcus aureus obtained from 127 bulk-tank milk samples of goats and sheep from Switzerland were characterised by pheno- and genotypic traits. Of the 293 S. aureus isolates, 193 (65.9%) were egg yolk-negative and 15 (5.1%) were negative for clumping factor and/or protein A determined by a latex agglutinating test system. For 285 isolates, PCR amplification of the 3' end of the coagulase gene showed a single amplicon. Five differently sized PCR products of 500, 580, 660, 740 and 820 bp were distinguished. In 191 isolates (n = 293) staphylococcal enterotoxin (SE) genes were detected: 123 isolates tested positive for SEC gene, 31 for SEG gene, 28 for SEA gene, 26 for SEJ gene, 24 for SEI gene, 4 for SEB gene and 4 for SED gene. Furthermore, 126 isolates were positive for the gene encoding the toxic shock syndrome toxin 1. Coagulase gene restriction profile analysis of the 145 isolates harbouring SEA or SEC genes revealed six different patterns using AluI and five different patterns using HaeIII. In summary, within these two groups, high genotypic uniformity within the different sized coagulase gene amplicons was demonstrated. This is the first study providing comprehensive characterisation data of S. aureus strains originating from bulk-tank milk samples of goats and sheep. Remarkable differences in phenotypic traits between S. aureus originating from goats and sheep and bovine milk were found. Moreover, the high prevalence of toxin-producing S. aureus may be important as it is relevant to food hygiene.  相似文献   

6.
Methicillin resistance rates of 41% for Staphylococcus aureus, 16% for S. intermedius, and 40% for S. schleiferi have recently been reported in canine patients. These were deemed to be reflective of referral and clinician-selection biases, which would imply significantly lower methicillin-resistant staphylococcal carriage rates in less-biased canine populations. In this study, swabs for bacterial culture were collected from five cutaneous sites on each of 50 healthy dogs and 59 dogs with inflammatory skin disease to determine prevalence of carriage and relative frequency of methicillin resistance in coagulase-positive staphylococci and S. schleiferi ssp. schleiferi. These were identified morphologically and by Gram's staining, catalase and coagulase testing, and biochemical speciation. Coagulase-positive staphylococci and S. schleiferi ssp. schleiferi were isolated from 88% (52 of 59) of affected dogs. Species identified in the culture-positive dogs were: S. aureus in 12%, S. intermedius (92%), S. schleiferi ssp. schleiferi (10%), and S. schleiferi ssp. coagulans (10%) with methicillin resistance rates of 17%, 8%, 20% and 20%, respectively. Coagulase-positive staphylococci were isolated from 74% (37 of 50) of healthy dogs: S. aureus (16%), S. intermedius (92%) and S. schleiferi ssp. coagulans (5%). Methicillin resistance rates were 0%, 3% and 50%, respectively. Of total methicillin-resistant isolates, 11 of 13 were positive for PBP2a via latex agglutination. Methicillin-resistant S. intermedius and S. schleiferi ssp. schleiferi isolates were all positive for the mecA gene via PCR. There was no significant difference in staphylococcal isolation or methicillin resistance between study groups. While present, methicillin-resistant coagulase-positive staphylococci are significantly less common in these less-biased populations than in the clinical isolates previously reported from this institution which provided the impetus for this study.  相似文献   

7.
Milk and dairy products are frequently contaminated with enterotoxigenic Staphylococcus aureus, which is often involved in staphylococcal food poisoning. The distribution of genes encoding staphylococcal enterotoxins (SE) in S. aureus isolated from bovine, goat, sheep and buffalo milk and dairy products was verified by the presence of the corresponding SE production. A total of 112 strains of S. aureus were tested for SE production by immuno-enzymatic (SEA-SEE) and reversed passive latex agglutination (SEA-SED) methods, while multiplex-PCR was applied for SE genes (sea, sec, sed, seg, seh, sei, sej and sel). Of the total strains studied, 67% were detected to have some SE genes (se), but only 52% produced a detectable amount of the classic antigenic SE types. The bovine isolates frequently had enterotoxin SEA, SED and sej, while SEC and sel predominated in the goat and sheep strains. The results demonstrated (i) marked enterotoxigenic S. aureus strain variations, in accordance with strain origin and (ii) the two methods resulted in different information but concurred on the risk of foodstuff infection by S. aureus.  相似文献   

8.
This study was conducted to investigate polymorphism of the coagulase gene of Staphylococcus aureus causing bovine mastitis. One hundred eighty-seven strains of S. aureus were isolated from bovine mastitic milk samples obtained from 187 different Danish dairy farms. The isolates were characterised for restriction fragment length polymorphism (RFLP) of the coagulase gene. A variable region of the coagulase gene was amplified using the polymerase chain reaction (PCR) followed by AluI restriction enzyme digestion. A total of 15 different RFLP patterns were observed. The predominant pattern was found in 35% of the isolates. The ease of analysing coagulase gene polymorphisms among a large number of strains, and the multiple distinct polymorphic patterns generated, supports the use of this technique in epidemiological investigations of bovine mastitis. The predominating variants may have predelection for causing intramammary infections.  相似文献   

9.
One hundred and sixty-six Staphylococcus aureus isolates from mastitic milk samples from different cows on 26 farms were investigated for staphylococcal enterotoxins(SEs) and toxic shock syndrome toxin-1(TSST-1) by polymerase chain reaction(PCR) and reverse passive latex agglutination assay(RPLA). SEs and the TSST-1 gene were detected in thirty-seven isolates based on a multiplex PCR; SEA was detected in 32 isolates, SEB in 3 isolates, SEC in 1 isolate, and SEA and the TSST-1 gene in 1 isolate. Of the 37 enterotoxigenic isolates, thirty-three isolates were enterotoxigenic according to RPLA, where 29 isolates produced SEA, 3 isolates produced SEB, and 1 isolate produced SEC. The enterotoxin-producing S. aureus isolates were further characterized by pulsed-field gel electrophoresis(PFGE). A macrorestriction analysis revealed 11 PFGE patterns. Among the 33 enterotoxigenic S. aureus isolates, 45.4% exhibited the same PFGE pattern I. Accordingly, although the enterotoxin-producing S. aureus isolates from bovine mastitis were genetically diverse, 1 common genotype prevailed on the farms, indicating that PFGE pattern I isolates may be the most disseminated in Korea.  相似文献   

10.
In this study, bacterial cultures were collected from five sites on each of 50 healthy cats and 48 cats with inflammatory skin disease (ISD), to determine prevalence of carriage and relative frequency of methicillin resistance in coagulase-positive staphylococci and Staphylococcus schleiferi ssp. schleiferi. Latex agglutination testing for penicillin-binding protein 2a (PBP2a) and pulsed field gel electrophoresis (PFGE) were performed on all methicillin-resistant (MR) isolates. Polymerase chain reaction (PCR) for the mecA gene was performed on MR S. intermedius and S. schleiferi isolates. Staphylococcal chromosomal cassette (SCCmec) typing was performed on all MR S. aureus isolates. Coagulase-positive staphylococci and S. schleiferi ssp. schleiferi were isolated from 24 of 48 cats with ISD: Staphylococcus aureus (14 of 24, 58%), Staphylococcus intermedius (11 of 24, 46%), Staphylococcus schleiferi ssp. schleiferi (1 of 24, 4%), and Staphylococcus hyicus (1 of 24, 4%). Prevalence of MR was 7% for S. aureus, 0% for S. intermedius, 100% for S. schleiferi ssp. schleiferi, and 0% for S. hyicus. Coagulase-positive staphylococci were isolated from 17 of 50 healthy cats: S. aureus (10 of 17, 59%), S. intermedius (11 of 17, 65%), and S. schleiferi ssp. coagulans (1 of 17, 6%). Prevalence of MR was 20% for S. aureus, 18% for S. intermedius, and 0% for S. schleiferi ssp. coagulans. All MR isolates were positive for PBP2a via latex agglutination. Methicillin-resistant S. intermedius and S. schleiferi ssp. schleiferi isolates were also positive for the mecA gene via PCR. Methicillin-resistant S. aureus isolates were identified as SCCmec type II. Results of PFGE indicated heterogeneity among isolates. There was no significant difference in staphylococcal isolation or methicillin resistance between study groups. While present, MR coagulase-positive staphylococci are significantly less common in these study populations.  相似文献   

11.
A total number of 640 staphylococci isolated from cows' milk were tested by latex agglutination and coagulase tests. About 50% of coagulase positive and 5% of coagulase negative staphylococci were positive to the latex agglutination tests. Latex agglutination tests were found to be not satisfactory for determining the coagulase status of staphylococci isolated from cows' milk.  相似文献   

12.
The present study was designed to comparatively investigate 25 Staphylococcus aureus strains isolated from bovine subclinical mastitis. The S. aureus strains, obtained from six different farms at five locations in one region of Germany, were characterized by phenotypic and genotypic methods. The S. aureus could be identified and further characterized by their cultural, biochemical and hemolytic properties. To analyze the epidemiological relationship the isolates were subjected to DNA fingerprinting by macrorestriction analysis of their chromosomal DNA, by PCR amplification of the gene encoding the 16S-23S rRNA intergenic spacer, by PCR amplification of the gene encoding the IgG binding region and the X region of protein A and by amplifying, and subsequent, digestion of the gene encoding staphylococcal coagulase. The macrorestriction analysis revealed five DNA restriction patterns with DNA patterns I, III and IV occurring in three, four, and three different farms, respectively. In addition, clones with different DNA patterns could be found within one herd. The PCR products for the spacer DNA, the spa gene encoding the X region of protein A and the coa gene encoding coagulase corresponded mostly to the pattern observed by DNA fingerprinting. Amplification of the gene encoding the IgG binding region revealed sizes of 620 bp for 20 of the isolates and 280 bp for four isolates indicating, for the latter, a deletion of segments in this region. These findings show, that single, widely distributed clones seemed to be responsible for cases of bovine subclinical mastitis found in one region of Germany.  相似文献   

13.
Exfoliative toxin A (ETA), produced by Staphylococcus aureus, is the causative agent of staphylococcal scalded-skin syndrome (SSSS) in children. Recently, we reported that ETA was detected by reverse passive latex agglutination in three isolates of S. aureus from cow's milk, but that these ETA-positive isolates did not cause the so-called Nikolsky sign in neonatal mice. In this study, therefore, the eta gene encoding ETA and regulatory genes of these bovine isolates were analyzed by the polymerase chain reaction (PCR) and sequencing. The eta gene was amplified from three bovine isolates by PCR and their resulting nucleotide sequences found to correspond to the eta gene from the human isolate, except for three nucleotides in the upstream region of the eta open reading frame (ORF). An accessory gene regulator (agr), which is a global regulatory locus, was detected in these bovine isolates by PCR amplification. In addition, the ORF (J-4), located 120 bp upstream from the eta ORF of the human isolate, was also amplified from these bovine isolates, with their nucleotide sequences differing at 32 positions from the human isolate. Bovine and human ORF J-4 equally enhanced production of ETA in the recombinants of the eta gene, suggesting that the variation in bovine ORF J-4 may be not be the cause of the difference in amount of ETA produced by bovine and human isolates.  相似文献   

14.
Staphylococcus aureus is a frequent cause of animal and human infections. The aim of the present study was to test diversity of the populations of S. aureus colonising cattle and humans sharing an infected environment. Eighty-six S. aureus isolates obtained from dairy cows, from people coming into contact with dairy cows on the farm and the other farm personnel were characterized by restriction fragment length polymorphism of the coagulase gene. Molecular analyses identified ten polymorphism types with prevalent presentation of type II in isolates from cow's milk and type IV in isolates from people coming into contact with dairy cows on the farm (the cattlemen) and the other farm personnel. Seven further genotypes were identified among the isolates from the cattlemen. The results indicate that the strains dominating in human population did not equate to the causative agents of bovine mastitis.  相似文献   

15.
从奶牛分离得到耐甲氧西林金黄色葡萄球菌（methieillin—resistant Staphylococcus aureus,MRSA）。按常规方法复苏菌株,用血浆凝固酶试验鉴定SA。用KB法、琼脂筛选法、生化鉴定法（VITEK32）、聚合酶链反应等鉴定MRSA。常规分离鏊定的葡萄球菌468株,其中凝固酶阴性葡萄球菌（coagulase negative Staphylococcus,CNS）361株,检出率为77．149,6,金黄色葡萄球菌（Staphylococcus aureus,SA）105株,检出率为22．44％,MRSA36株检出率为34．29％,2株未定型,占0．42％。而MRSA在乳房炎奶样中检出率高达34．29％,表明新疆兵团部分垦区牛场MRSA已经呈蔓延趋势。  相似文献   

16.
OBJECTIVE: To determine the methicillin-resistant profile of staphylococcal isolates from the skin of dogs with pyoderma. ANIMALS: 90 dogs with pyoderma. PROCEDURE: Staphylococci isolated from dogs with pyoderma were tested for susceptibility to methicillin by use of a standard disk diffusion test with oxacillin disks. The DNA extracted from the isolates was tested for the mecA gene that encodes the penicillin-binding protein 2a (PBP2a) by use of a polymerase chain reaction (PCR) assay. The expression of PBP2a was determined with a commercial latex agglutination assay. Species of staphylococcal isolates were identified by use of morphologic, biochemical, and enzymatic tests. RESULTS: Most of the isolated staphylococci were methicillin-susceptible, coagulase-positive Staphylococcus intermedius isolates. Whereas only 2 of 57 S. intermedius isolates were resistant to methicillin, approximately half of the isolates had the mecA gene and produced PBP2a. Staphylococcus schleiferi was the second most common isolate. Widespread resistance to methicillin was found among S. schleiferi isolates. More coagulase-negative S. schleiferi isolates were identified with mecA gene-mediated resistance to methicillin, compared with coagulase-positive S. schleiferi isolates. CONCLUSIONS AND CLINICAL RELEVANCE: The latex agglutination assay for the detection of PBP2a expression coupled with the PCR assay for the mecA gene may provide new information about emerging antimicrobial resistance among staphylococcal isolates.  相似文献   

17.
Three slide agglutination tests for identification of Staphylococcus aureus were compared. The agglutination tests used for evaluation were Staphaurex (Wellcome Diagnostics), Staphyslide-Test (BioMerieux), and ANI S. aureus TEST (Ani Biotech Oy). A total of 347 isolates were analyzed, including 288 strains of S. aureus, 49 of S. epidermis, 11 of S. intermedius, 12 strains of other staphylococci and 14 non-staphylococcal strains. One hundred of the S. aureus strains were isolates from cases of food poisoning, 129 from mastitis and 59 from other clinical cases. The sensitivities of the tests were also compared using diluted suspensions of S. aureus strains and with purified Protein A dilutions. The results showed that the sensitivities of the tests were 98.6%, 97.9% and 99.0% for Staphaurex, Staphyslide-test and ANI S. aureus TEST, respectively. The specificities were 100% for the Staphyslide test and 98.8% for both the ANI S. aureus TEST and the Staphaurex test. The sensitivities measured with diluted S. aureus strain suspensions and Protein A solutions were equal with the Staphaurex and ANI S. aureus TEST. All the agglutination tests studied proved to be practical, easy to use and accurate for the rapid identification of S. aureus strains from culture isolates.  相似文献   

18.
The species distribution, susceptibility to 19 antimicrobial agents and presence of selected genes encoding resistance to macrolides, streptogramins and tetracyclines were examined among 118 staphylococcal isolates from infections of poultry in Denmark. Isolates were identified using a combination of conventional biochemical testing and 16S rDNA sequencing. The most common species were Staphylococcus aureus (83), Staphylococcus hyicus (11), Staphylococcus xylosus (9) and Staphylococcus cohnii (6). The isolates were susceptible to most antimicrobials tested. A high frequency of S. aureus (30%) was resistant to ciprofloxacin. Only six (7%) S. aureus isolates and one Staphylococcus saprophyticus were penicillin resistant. Resistance to sulphamethoxazole was observed among 16 (19%) of S. aureus isolates and two coagulase negative staphylococci (CNS). Twenty (24%) of the S. aureus isolates were resistant to erythromycin and 19 of these isolates contained the ermA gene, whereas the remaining isolate contained the ermC gene. Eleven (48%) of the novobiocin resistant CNS were resistant to erythromycin and all these isolates contained the ermA gene. Two isolates identified as S. xylosus, were found to be resistant to streptogramins and both contained the vatB- and the vgaB-genes. Thirty-nine (47%) of the S. aureus isolates, three of nine S. hyicus and eight of the 23 novobiocin resistant CNS were tetracycline resistant and all contained the tet(K) gene. A single S. aureus isolate also contained the tet(M) gene. The present study showed a frequent occurrence of resistance to fluoroquinolones, tetracycline and macrolides among staphylococci isolated from broilers in Denmark, whereas the occurrence of resistance to other antimicrobial agents remains low. Similar genes, encoding resistance to erythromycin, tetracycline and streptogramins to those previously observed, were detected.  相似文献   

19.
Two hundred thirty one Staphylococcus aureus isolates from bovine mastitic milk were discriminated into 60 patterns and 16 lineages by pulsed-field gel electrophoresis (PFGE). The tested isolates were also investigated using coagulase and capsule serotyping and PCR for possession of genes that encode staphylococcal enterotoxins (sea to sei), enterotoxin-like toxins (selj to selr), and toxic shock syndrome toxin (tst). One hundred seventy three of the isolates (74.9%) possessed one or more toxin genes, while no egg-yolk factor was detected in most of them. The most common combinations of toxin genes possessed by the tested isolates were sec, seg, sei, sell, and tst, or seg and sei, or sec, seg, sei, sell, seln, and tst. Two hundred and ten of the isolates (91.0%) serotyped coagulase VI, and 207 of the isolates (89.6%) expressed serotype 5 or 8 capsules. These results suggested that isolates belonging to two major lineages have spread all over Hokkaido as bovine mastitic isolates. Additionally, no remarkable difference was recognized in the identification ratio of the isolates that belonged to the two major lineages between mastitis of subclinical origin and mastitis of clinical origin.  相似文献   

20.
Coagulase gene restriction fragment length polymorphism (RFLP) patterns were analyzed to determine the phylogenetic relationship among isolates of Staphylococcus aureus from the Czech Republic (n = 27), France (n = 48), Korea (n = 115) and the United States (n = 278). A total of 468 isolates of S. aureus were subtyped into 41 coagulase genotypes. Cluster analysis placed the 41 types into nine clusters. Eighteen API Staph profiles were determined for 102 S. aureus isolates representing 1 to 4 isolates of each coagulase type. The results of the study suggest that based on coagulase gene RFLP analysis, several genetic variants of S. aureus are prevalent. Comparison of coagulase and API Staph profiles indicated that the two identification system were independent of each other.  相似文献   

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