Evaluation of three slide agglutination tests for rapid identification of Staphylococcus aureus.

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.     

唾液乳杆菌的生长特性及抑菌作用

为了探讨唾液乳杆菌的生长特性及抑菌作用,测定2株唾液乳杆菌的生长曲线,并选用口腔变形链球菌、牙龈卟啉单胞菌及金黄色葡萄球菌为指示菌,采用牛津杯法进行体外抑菌实验.结果表明:2株唾液乳杆菌分别在接种2h和4h进入对数生长期,8h进入对数生长末期,14h和16h进入稳定期;2株唾液乳杆菌菌液及代谢产物对口腔变形链球菌、牙龈卟啉单胞菌及金黄色葡萄球菌均有抑菌作用,对口腔变形链球菌及牙龈卟啉单胞菌的抑菌作用强于金黄色葡萄球菌;2株唾液乳杆菌菌体及调整pH值为7.0的代谢产物没有抑菌作用;2株唾液乳杆菌的抑菌能力主要来自菌体的代谢产物,代谢产物中起抑菌作用的成分为酸或酸依赖性物质.     

Prevalence of oxacillin- and multidrug-resistant staphylococci in clinical samples from dogs: 1,772 samples (2001-2005)

OBJECTIVE: To determine whether resistance to oxacillin and other antimicrobials in 3 Staphylococcus spp commonly isolated from dogs increased from 2001 to 2005. DESIGN: Retrospective case series. SAMPLE POPULATION: 1,772 clinical samples of various types obtained from dogs examined at the University of Tennessee Veterinary Teaching Hospital or at regional veterinary hospitals and submitted to the bacteriology and mycology laboratories associated with the teaching hospital. PROCEDURES: Samples were submitted by attending veterinarians to the bacteriology and mycology laboratories for routine aerobic microbial culture. Identification and antimicrobial susceptibility procedures were performed on all isolates. Susceptibility reports for each antimicrobial and Staphylococcus spp were determined from aggregate electronically archived test results. Oxacillin and multidrug resistance for Staphylococcus intermedius was analyzed by reviewing disk diffusion zone measurements. RESULTS: Oxacillin resistance increased among S. intermedius isolates during the past 5 years, and the increase was associated with multidrug resistance. In 2005, 1 in 5 Staphylococcus spp isolates from canine clinical samples was resistant to oxacillin. The most common staphylococcal species isolated were S. intermedius (n = 37), Staphylococcus schleiferi (21), and Staphylococcus aureus (4), and frequencies of oxacillin resistance in isolates of these species were 15.6%, 46.6%, and 23.5%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Veterinarians should be aware of the potential for empiric drug treatment failures in instances where Staphylococcus spp infections are common (eg, pyoderma). Judicious use of bacterial culture and susceptibility testing is recommended.     

Identification of coagulase-positive staphylococci isolated from bovine milk

A total of 414 coagulase-positive staphylococcal strains obtained at the mastitis laboratory, National Veterinary Institute, Uppsala, Sweden, were studied. One hundred and seventy seven strains were used for a frequency study. Ninety-seven per cent were identified as Staphylococcus aureus, 2% as Staphylococcus intermedius and 1% as Staphylococcus hyicus. Two hundred and thirty seven strains with atypical hemolysis reactions on bovine blood agar were randomly selected, with the aim to increase the number of S. intermedius and S. hyicus strains available for testing. Eight different characteristics, including physiological, enzymatical and biochemical properties, were used to identify the coagulase-positive Staphylococcus species. The results of this study suggest that the following tests should be included for correct identification of the 3 different species of coagulase-positive staphylococci: P agar supplemented with acriflavin, beta-galactosidase and hemolytic reaction on chocolate agar. These 3 tests are simple and quick to perform and enable accurate for easy differentiation of the 3 coagulase-positive Staphylococcus species.     

Relations Between Udder Infection and Somatic Cells in Camel (Camelus dromedarius) Milk

Quarter milk samples (n = 391) from 101 camels were examined to study the occurrence and causes of mastitis in traditionally managed camels in eastern Sudan and to evaluate the value of the California Mastitis Test (CMT), somatic cell count (SCC) and adenosine triphosphate (ATP) in the detection of subclinical mastitis in the camel.One hundred and seventy (43.5%) of the quarter milk samples yielded pathogenic bacteria. Streptococcus agalactiae, other Streptococcus spp., Staphylococcus aureus, coag–ulase–negative staphylococci, and Escherichia coli were isolated from milk. Thirty–two (8.2%) quarter milk samples yielded mixed cultures, and 189 (48.3%) yielded no growth.Mean values for CMT, SCC and ATP were higher for quarters infected with major pathogens. However, a significant number of quarter milk samples had elevated values in these tests but were from quarters from which no bacteria were isolated. The ability of the tests to predict a positive bacteriology increased slightly when 2 or 3 tests were combined. kw|Keywords|k]inflammation; k]diagnostic tests; k]Mastitis; k]CMT; k]ATP; k]bacteriology; k]Sudan     

Comparison of three commercial rapid agglutination test kits for identification of coagulase positive staphylococci from foods and animals.

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.     

山羊皮下脓肿的病原分离与鉴定

为了解引起山羊皮下脓肿的主要病原,本研究从四川乐至县、金堂县和蓬溪县3个山羊养殖场无菌采集患皮下脓肿病羊脓液样本19份,通过细菌分离培养、生化试验及特异性PCR方法对其病原进行检测和鉴定,并通过药敏试验测定分离病原的药物敏感性。结果显示,PCR扩增法共检测出病原菌19株,其中伪结核棒状杆菌、金黄色葡萄球菌及化脓隐秘杆菌分离率分别为57.9%(11/19)、26.3%(5/19)及15.8%(3/19);采用细菌分离培养法分离到3种形态不同的病原菌共计17株,其中革兰氏阳性短杆菌经鉴定为伪结核棒状杆菌,分离率57.9%(11/19),革兰氏阳性球菌经鉴定为金黄色葡萄球菌,分离率为21.1%(4/19),革兰氏阳性杆菌经鉴定为化脓隐秘杆菌,分离率为10.5%(2/19),PCR鉴定较细菌分离培养法灵敏度更高。3种病原菌对丁胺卡那、氟苯尼考等多种药物敏感。结果表明,伪结核棒状杆菌是引起该地区山羊皮下脓肿的主要病原,金黄色葡萄球菌和化脓隐秘杆菌同样可引起山羊皮下脓肿,特异性PCR方法较细菌分离培养更为高效、准确。本研究结果可为后续进一步分析其生物学特性,以及四川地区山羊皮下脓肿的综合性防制提供依据。     

Antibiotic resistance of staphylococci from humans, food and different animal species according to data of the Hungarian resistance monitoring system in 2001

Based on data of the Hungarian resistance monitoring system the antibiotic resistance of Staphylococcus strains of human and animal origin was studied. No methicillin-resistant staphylococci harbouring mecA gene were isolated from animals in 2001. Penicillin resistance, mediated by penicillinase production, was the most frequent among Staphylococcus aureus strains isolated from humans (96%), from bovine mastitis (55%), from foods (45%) and from dogs. In staphylococci isolated from animals low resistance percentages to aminoglycosides (0-2%), fluoroquinolones (0.5-3%) and sulphonamides (0.5-4%) were found but in strains isolated humans these figures were higher (1-14%, 5-18% and 3-31%, respectively). The most frequent antibiotic resistance profiles of strains isolated from animals and food were penicillin/tetracycline, penicillin/lincomycin and penicillin/lincomycin/tetracycline. Penicillin/tetracycline resistance was exhibited by strains from mastitis (3), samples from the meat industry (31), poultry flocks (1), poultry industry (1), noodle (1) and horses (2). Penicillin/lincomycin resistance was found in 10 Staphylococcus strains from mastitis, 1 from the dairy industry, 1 from the meat industry and 6 from dogs. Isolates from mastitis (2), from the dairy industry (2), from pigs (1), from the meat industry (1) and from poultry (1) harboured penicillin/lincomycin/tetracycline resistance pattern. Multiresistant strains were usually isolated only from one and sometimes from two animal species; therefore, the spread of defined resistant strains (clones) among different animal species could not be demonstrated. These results also suggest that the transfer of antibiotic resistance of S. aureus from animals to humans probably occurs less frequently than is generally assumed.     

Determination of beta-lactamase production in strains of Staphylococcus aureus isolated from the milk of cows

Determination of sensitivity to penicillin G by a standard disk assay diffusion method was compared with a iodometric method of test papers to determine beta-lactamase production after Jorgensen in Staphylococcus aureus strains isolated from cow's milk from different farms. Out of 179 test strains, 32 strains 17.8%) were found to be well sensitive in the diffusion test; eight of these strains (25.0%) were demonstrated to produce beta-lactamase. 54 strains (30.2%) were sensitive. 27 strains (50%) of this group produced beta-lactamase. 93 strains (51.9%) were resistant to penicillin G in the diffusion test. 86 strains (92.5%) were found to produce beta-lactamase and seven strains were negative in this test. Using the diffusion test of sensitivity in these cultures, 86 strains were sensitive (48.1%) and 93 strains were resistant (51.9%). Beta-lactamase was produced by 121 strains (67.6%) and no beta-lactamase production was recorded in 58 strains (32.4%). Differences in the results of both tests were manifest mainly in the set of strains qualified as sensitive (inhibition zone diameter 24 to 16 mm) and well sensitive (inhibition zone diameter larger than 25 mm). The results indicate that the currently performed diffusion test of sensitivity to penicillin G should be accompanied by an assay of beta-lactamase production. The iodometric method of test papers is simple, rapid and cheap and can be made in any bacteriological laboratory. The high resistance of Staphylococcus aureus strains to penicillin G documents that this antibiotic is little efficient in the treatment of mastitis of this etiology in the given region.     

金黄色葡萄球菌毒力及其免疫原性评价方法研究

为建立评价金黄色葡萄球菌毒力和用于筛选免疫保护性菌株的技术方法,选取小鼠腹腔攻毒方法确定的强毒力和弱毒力菌株各3株,经小鼠后腿肌肉注射不同剂量,比较20 d的临床病变差异,确定小鼠后腿内侧肌肉注射0.25 mL、OD600=0.6的剂量可以评价不同金黄色葡萄球菌的毒力。利用该方法比较了6株强毒力菌株的毒力差异,并用于2株免疫保护性菌株的筛选。结果证明建立的金黄色葡萄球菌毒力评价方法可以精确、客观比较不同菌株毒力差异,并可用于免疫保护性菌株的筛选。     

宁夏地区奶牛乳房炎金黄色葡萄球菌耐药性分析

为了解宁夏地区奶牛乳房炎金黄色葡萄球菌的耐药情况,采用药敏纸片扩散法,测定了50株奶牛乳房炎金黄色葡萄球菌对常用的17种抗茵药物的耐药性.同时采用产色头孢菌素法进行β-内酰胺酶的检测,并采用苯唑西林纸片法进行耐甲氧西林金黄色葡萄球菌(MRSA)的检测.结果表明,所有菌株除了对利福平、万古霉素100％敏感以外,对其他15...     

Reinfection of bovine mammary glands following dry-cow antibiotic therapy

Dry-cow antibiotic therapy (DCT) was administered to quarters with Staphylococcus aureus or streptococcal infections and the quarters were closely monitored for the presence of new or reactivated mammary infections throughout the dry period and the following lactation. Strains of S. aureus were characterized using a selection of biotyping tests to allow a comparison of S. aureus strains isolated before and after DCT. Cows with 3-4 quarters infected prior to DCT had a high susceptibility to reinfection in the following year. In contrast, for cows with 1-2 quarters infected prior to DCT and for heifers with no previous history of infection, the susceptibility to reinfection or new infection was very low. The majority of the S. aureus infections appearing in the lactation following DCT were due to S. aureus strains which differed from strains isolated prior to DCT, suggesting that these were new infections. Histopathological examination of quarters which had had recurrent S. aureus infections revealed lesions typical of chronic S. aureus mastitis, including extensive lobular fibrosis and atrophy.     

牛源耐甲氧西林金黄色葡萄球菌的分离鉴定

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。     

青海地区奶牛乳房炎葡萄球菌的分离鉴定与药敏试验

为了掌握导致青海地区奶牛乳房炎的最主要病原菌——葡萄球菌流行情况及其对常用药物的敏感性,从而为奶牛乳房炎的治疗提供参考依据,本试验在青海地区18个奶牛场共采集243份乳房炎乳样。应用传统方法进行葡萄球菌的分离培养;通过试管法血浆凝固酶试验与生化鉴定方法,本次共分离出金黄色葡萄球菌43株,木糖葡萄球菌与产色葡萄球菌各6株,腐生葡萄球菌5株,松鼠葡萄球菌、表皮葡萄球菌和人葡萄球菌各4 株,头葡萄球菌和模仿葡萄球菌各2株;经K-B纸片扩散法对葡萄球菌耐药性检测结果显示,该地区葡萄球菌主要对头孢类、林可霉素、阿米卡星比较敏感,部分菌株对恩诺沙星与庆大霉素敏感,从而为该地区奶牛乳房炎的有效预防和治疗提供科学依据。     

Phenotypic and genotypic properties of Staphylococcus aureus subsp. anaerobius isolated from lymph node abscesses of goats

In the present study 20 staphylococci isolated from lymph node abscesses of 19 goats of two herds in Western Poland could be identified as Staphylococcus aureus subsp. anaerobius. All 20 strains grew under microaerobic conditions, were negative in the catalase test, showed the typical phenotypic properties of 5. aureus and could genotypically be identified by a positive sa442, 235 rDNA, nuc, coa and spa PCR reaction. The variable regions of the coa and spa gene of the 20 strains appeared with uniform amplicon sizes, respectively. All 20 strains were negative for 12 additionally investigated enterotoxin encoding genes, tst and ssl7 and positive for the gene cap8. Identical properties could be observed for S. aureus subsp. anaerobius DSM 20714. Amplification and sequencing of kat gene of a single Staphylococcus aureus subsp. anaerobius strain of the present study and S. aureus subsp. anaerobius DSM 20714 revealed a complete identity of the kat sequences of both strains and a katB sequence obtained from GenBank (AJ000471). The bacteria were additionally investigated for relatedness by macrorestriction analysis of chromosomal DNA with subsequent pulsed-field gel electrophoresis (PFGE), yielding, corresponding to the above mentioned PCR results, identical PFGE patterns for all 20 Staphylococcus aureus subsp. anaerobius strains isolated in Western Poland and the S. aureus subsp. anaerobius reference strain DSM 20714.This indicates the clonal identity of the strains isolated in Western Poland and the S. aureus subsp. anaerobius reference strain. The route of infection of the two herds in Western Poland with a bacterial clone originally isolated in Spain remains unclear.     

Indications for both host-specific and introduced genotypes of Staphylococcus aureus in marine mammals

Staphylococcus aureus is present in the marine environment and causes disease in marine mammals. To determine whether marine mammals are colonized by host-specific strains or by strains originating from other species, we performed multi-locus sequence typing on ten S. aureus strains isolated from marine mammals in the U.K., the Netherlands, and the Antarctic. Four new sequence types of S. aureus were discovered. S. aureus strains from a southern elephant seal (n=1) and harbour porpoises (n=2) did not cluster with known S. aureus strains, suggesting that they may be host species-specific. In contrast, S. aureus strains from harbour seals (n=3), other harbour porpoises (n=3), and a grey seal (n=1) clustered with S. aureus strains previously isolated from domestic ruminants, humans, or birds, suggesting that these S. aureus strains in marine mammals were introduced from terrestrial species.     

Antimicrobial susceptibility of Staphylococcus spp. isolated from mammary parenchymas of slaughtered dairy cows

The high prevalence of the great resistance to antimicrobials shown by the aetiological agents of infectious bovine mastitis, often leads to chronic recurrent mastitis, one of the main causes of early culling of dairy cows. The purpose of this study was to determine the in vitro susceptibility pattern of Staphylococcus spp. isolated from mammary parenchymas of slaughtered dairy cows, to different anti-microbials. A total of 45 Staphylococcus spp. strains [33 coagulase-negative Staphylococcus (CNS) and 12 Staphylococcus aureus (SA)] were used. These strains were tested with 12 different antimicrobials by the Kirby and Bauer standardized disc diffusion method; 84.44% and 86.66% of the 45 strains were resistant to ampicillin and penicillin, respectively. The highest sensitivity was to cephalothin (84.44%), gentamicin (80%) and to sulphazotrin (77.77%). CNS showed higher resistance (P < 0.05) than SA. The in vitro susceptibility pattern of Staphylococcus spp. strains isolated from mammary parenchymas studied in the present investigation was similar to that observed in recent studies of in vitro and in vivo susceptibility patterns of Staphylococcus spp. isolated from cases of bovine mastitis.     

江苏地区奶牛源葡萄球菌耐药性分析与红霉素诱导的克林霉素耐药检测

为指导江苏地区奶牛场奶牛乳房炎的临床用药,本研究对2015-2018年江苏地区部分奶牛场的牛奶样品进行细菌分离,使用基质辅助激光解析电离飞行时间质谱(MALDI-TOFMS)方法和纸片法对分离菌株进行鉴定和药物敏感性分析,对分离得到的葡萄球菌进行了葡萄球菌D环实验,并且使用PCR技术检测了D环实验阳性菌株携带的耐药基因...     

奶牛乳房炎金黄色葡萄球菌的分离鉴定

为检测江苏省某奶牛场中乳房炎是否为金黄色葡萄球菌所致,采取4份患病乳汁样本进行试验分离和鉴定,并针对金黄色葡萄球菌采用分离后鉴定,结果显示,分离到的2株致病菌为金黄色葡萄球菌,其他菌株还包括大肠杆菌、肠球菌等,为多种致病病原菌同时引起,主要为金黄色葡萄球菌感染。     

Isolation and Identification of Pathogenic Bacteria Causing Bovine Subclinical Mastitis in Eastern Hebei Province

In this study, the milk samples of 1 021 cows in eight dairy farms in Eastern Hebei Province were collected and detected with LMT reagent and somatic cell count for subclinical mastitis. Pathogenic bacteria in subclinical mastitis positive milk samples were isolated and identified.The results showed that 60.63%(619/1 021) of the sampled cows were diagnosed with subclinical mastitis, and mixed infections accounted for 88.21%(546/619) of the cases. In addition, 82 strains of 14 species were isolated from the subclinical mastitis positive milk samples, including 36 strains of Staphylococcus(43.90%), 33 strains of Streptococcus(40.24%), 8 strains of Enterobacteriaceae(9.76%) and 5 strains of Corynebacterium(6.10%), respectively. The results proved that Staphylococcus aureus and Streptococcus agalactiae are the main pathogenic bacteria causing bovine subclinical mastitis in Eastern Hebei Province.