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1.
The objective of the study was to investigate reservoirs and transmission of S. aureus in ewes and lambs in 3 meat sheep flocks. Repeated sampling of milk, teat skin, nasal- and vaginal mucous membranes was performed and samples were analysed for S. aureus. For comparison, samples were also collected from cows and young heifers in 3 dairy cattle herds. Selected isolates were compared by pulsed-field gel electrophoresis (PFGE). S. aureus was detected in 8 (1.5%) of 520 milk samples from ewes and in 38 (6.4%) of 588 milk samples from cows. From body site swabs, S. aureus was found in 394 (32.6%) of 1208 samples from sheep and in 67 (16.0%) of 420 samples from cattle. The proportion of S. aureus-positive nasal swabs from ewes and cows were 56.7% and 13.9%, respectively. From lambs, 58.2% of the nasal swabs were S. aureus-positive. In each flock, one S. aureus pulsotype predominated. Identical S. aureus pulsotypes were found in milk and from body sites. Paired S. aureus isolates from the nasal cavity of (i) ewes and their lambs, (ii) twins and (iii) from repeated swabs of individual ewes were compared by PFGE, and in the majority of cases the two isolates were identical. The results contribute new knowledge indicating frequent transmission of S. aureus between the dam and her lambs and within animals in a flock. In contrast to cattle, S. aureus is frequently present in the nose of sheep which may represent the primary reservoir of S. aureus in sheep flocks.  相似文献   

2.
Milk samples (10 ml) were collected aseptically from infected and healthy mammary glands of 20 range ewes in the early stages of unilateral acute mastitis. The ewes were on 5 different ranches in the Northern Rocky Mountain region of the United States. The samples were plated on tryptose blood agar and examined for bacteria of possible etiologic significance. Twelve of the 20 ewes were infected with Pasteurella haemolytica, 4 ewes with Staphylococcus aureus, and 1 ewe with both bacteria. Twelve of the P haemolytica infections were in pure culture as were 4 S aureus infections. The 13 isolates of P haemolytica represented 6 different serotypes. Isolates of P haemolytica from ewes on the same ranch were as serologically diverse as were isolates from ewes in different herds. The 5 isolates of S aureus were similar antigenically. Bacterial isolates were not obtained from the milk of clinically healthy mammae.  相似文献   

3.
The purpose of this study was to assess the prevalence of Staphylococcus aureus nasal carriage of dairy sheep in farms producing cheeses manufactured with raw ewe's milk. The study showed that 29% of ewes carried S. aureus in their nares. The genetic diversity of the 136 isolates recovered from the anterior nares of the ewes, from the ambient air of the milking parlour and from cheeses was investigated using pulsed-field gel electrophoresis (PFGE) of DNA SmaI digests. The genotyping results showed that 75 out of 106 isolates recovered from nasal carriage in dairy sheep belonged to a dominant pattern (previously named OV) and a genetically related pattern (named OV'). The same profile (OV or OV') was found in the ambient air and cheeses, suggesting a continuum between isolates within these different compartments.  相似文献   

4.
We investigated the genetic diversity of 179 Staphylococcus aureus isolates recovered from various sites in 10 farms producing cheeses manufactured with raw ewe's milk. Isolates were collected from handcrafted cheeses, bulk tank milk, milk from half-udders, skin abscesses on the udder if present, hands and anterior nares of farmers, and air of the milking area. The isolates were typed using pulsed-field gel electrophoresis (PFGE) of DNA SmaI digests and compared to other isolates of S. aureus isolated in different hosts or in different locations. The results showed that nine farms were contaminated by S. aureus isolates with identical banding patterns (named OV) or by genetically related isolates (named OV'). These dominant banding patterns were found in a variable proportion of the samples from each farm (range: 11-100%). Most of the strains isolated from nasal carriage or strains isolated from other regions or from other animal species had different PFGE patterns to OV or OV', except for three strains. These results show that a single clone of S. aureus is widely distributed both in infected mammary glands and in cheese produced from raw milk. This study confirms that infected mammary glands are the main source of the contamination of dairy products in sheep.  相似文献   

5.
Macrolide and lincosamide (ML) resistance and the related resistance genes of staphylococci were assessed from cases of bovine subclinical mastitis. Of the 104 Staphylococcus aureus and 62 coagulase negative staphylococcus (CoNS) isolates, 26 (25%) and 12 (19.4%) were resistant to ML, respectively. While constitutive ML resistance phenotype accounted for 15.4% (16/104) of S. aureus and 8.1% (5/62) of CoNS, inducible ML resistance phenotype accounted for 2.9% (3/104) of S. aureus and 3.2% (2/62) of CoNS. Among erythromycin-resistant isolates, single or various combination of different resistance genes were detected. The results of this study showed that ML resistance was prevalent among staphylococci from subclinical bovine mastitis cases in Hatay, Turkey. Therefore, a continuous surveillance is necessary to minimise the spread of antimicrobial-resistant staphylococci.  相似文献   

6.
为了解猪圆环病毒3型(PCV3)在云南省不同地区猪群中的流行情况,针对PCV3基因保守区域设计特异性引物,优化反应条件,建立PCR快速检测方法,并采用该方法对采自云南省不同地市431份样品进行检测,将获得的部分毒株全基因序列进行遗传进化分析。结果显示:本研究成功建立了一种快速、特异和灵敏的PCV3检测方法;云南省12个地(市)29县(区)中,8个地(市)12个县(区)检测出阳性样品;431份样品中有43份PCV3阳性样品,阳性率为9.98%;获得的3株PCV3全基因组序列与参考毒株之间的核苷酸同源性为98.6%~99.5%,进化树显示3株云南毒株形成一个小的进化分支,属于PCV3a基因型。本研究结果表明,PCV3在云南省多个地区呈一定的流行趋势,流行毒株以PCV3a基因型为主,有必要进一步开展云南地区PCV3流行病学调查,并提出防控对策。  相似文献   

7.
Staphylococcus aureus is a common pathogen which can colonise and infect not only man, but also domestic animals. Especially, infection of cattle is of high economic relevance as S. aureus is an important causal agent of bovine mastitis. In the present contribution, a DNA microarray was applied for the study of 144 different gene targets, including resistance genes and genes encoding exotoxins, in S. aureus isolated from cows. One hundred and twenty-eight isolates from Germany and Switzerland were tested. These isolates were assigned to 20 different strains and nine clonal complexes. The majority of isolates belonged either to apparently closely related clonal complexes 8, 25, and 97 (together 34.4%) or were related to the sequenced bovine strain RF122 (48.4%). Notable characteristics of S. aureus of bovine origin are the carriage of intact haemolysin beta (in 82% of isolates tested), the absence of staphylokinase (in 89.1%), the presence of allelic variants of several exotoxins such as toxic shock syndrome toxin and enterotoxin N, and the occurrence of the leukocidin lukF-P83/lukM (in 53.1%). Two isolates were methicillin-resistant S. aureus (MRSA). One of them was a clonal complex 8 MRSA related to the epidemic MRSA strain Irish 01. The other one belonged to ST398/spa-type 34 resembling a newly emerging MRSA strain which has been described to occur in humans as well as in domestic animals. The presence of these two strains highlights the possibility of transfers of S. aureus strains between different host species.  相似文献   

8.
Little information is available regarding the molecular epidemiology of Staphylococcus aureus-induced mastitis in dairy sheep. In this study, 4 different typing techniques were compared in typing 26 S. aureus isolates, predominantly from cases of subclinical mastitis in dairy ewes. The 4 techniques were pulsed-field gel electrophoresis (PFGE), restriction fragment length polymorphism (RFLP) on 2 genes (coagulase and clumping factor B), randomly amplified polymorphic DNA-polymerase chain reaction (PCR) (RAPD-PCR), and multilocus sequence typing (MLST). On the basis of discriminatory power as the key parameter of typing systems, MLST and PFGE were found to be the most powerful techniques. The MLST and PFGE could contribute to epidemiological surveillance and evaluation of mastitis control programs, by documenting prevalence and dissemination of endemic clones in infected populations. The results of this study show that a single clone of S. aureus is widely distributed in infected ewe mammary glands.  相似文献   

9.
A total of 444 samples of raw chicken meat (thighs, breasts, wings, livers, gizzards, hearts and ovaries) that retailed at 145 different supermarkets in 47 prefectures in Japan were examined for contamination with Staphylococcus aureus in association with its enterotoxigenicity. S. aureus was isolated from 292 (65.8%) of the samples, and from 131 of the 145 supermarkets. There was no significant difference in the detection rate of S. aureus according to the type of meat examined. About 80% of 714 isolates belonged to the poultry (57.1%) and human biotypes (22.1%). Seventy-eight (21.7%) of 360 isolates were enterotoxigenic and isolated from 78 samples in 53 supermarkets in 31 prefectures. Staphylococcal enterotoxins (SEs) produced were SEB (50 isolates), SEA (14), SEC (8), SED (2), SEA+SEB (2), and SEA+SEC (2). Most of the enterotoxigenic isolates belonged to the human and poultry biotypes, coagulase type VII, VIII or IV, and were lysed by phages of group III. Identical SE types, biotypes, coagulase types and pulsed-field gel electrophoresis (PFGE) patterns were shown in isolates from different types of meat at the same supermarket and from samples taken from different supermarkets in the same prefectures or in isolates from samples obtained from several different prefectures. Among the 50 SEB-producing isolates, 27 yielded three similar PFGE patterns that differed by only a few fragments, suggesting that they were closely related genetically. The three patterns were found in isolates of samples that retailed at 17 supermarkets in 11 prefectures, indicating that they may be disseminated among raw chicken meat in Japan.  相似文献   

10.
Mastitis caused by Staphylococcus aureus is a disease of major economic importance to the dairy industry. Transmission occurs during milking, with chronically-infected cows acting as the major reservoirs of infection. PCR-coagulase gene typing of 151 S. aureus isolates from seven farms generated only six PCR types, with 110 (73%) isolates assigned to PCR type 1 and 23 (15.2%) isolates assigned to type 2. PCR type 1 was the predominant type on five of the seven farms, including farms in geographically separated regions of Victoria, while type 2 predominated on two farms. With the exception of the 41 isolates from one farm, all isolates were resistant to penicillin, but susceptible to other antibiotics that are routinely used to manage mastitis in dairy cattle. Nine of 11 cows with chronic S. aureus infection showed evidence of persistence of a single PCR type for periods of up to 9 months. Two different PCR types of S. aureus were isolated from the other two cows over the same period.  相似文献   

11.
牛源金黄色葡萄球菌凝固酶基因的分型   总被引：3，自引：0，他引：3  
为了了解我国不同地区奶牛场金黄色葡萄球菌基因型的分布情况,采用凝固酶基因（Coa）扩增的分型方法,对在奶牛乳房炎奶样中所分离到的26株金黄色葡萄球菌进行了分型。结果显示,26株金黄色葡萄球菌共分为5个基因型,黑龙江省分离株以PCR 3型为主（10/16）。发现在同一牛群中的分离株可以存在相同的基因型,也可以存在不同的基因型;而不同牛群中的分离株也可属于同一基因型。这种结果提示,在某个或某些牛群中存在某一金黄色葡萄球菌的流行型,但也可能存在多个金黄色葡萄球菌的克隆。  相似文献   

12.
Since staphylococcal infections are the main pathological problem in rabbit does, the objective of this study was to characterize epidemiologically Staphylococcus aureus isolates from different lesion types in rabbits. Using 3 genetic markers (coagulase, staphylococcal protein A and clumping factor B genes), 22 different genotypes were identified among 301 isolates recovered from 259 rabbit does with 10 different kinds of chronic purulent lesions. These infected rabbits were obtained from 30 herds located in the Valencia province on the Spanish Mediterranean coast. The most frequent genotype was designated A1/II1/delta (coa/spa/clfB combination genotype) and represented 70.76% of the isolates. Although most genotypes were previously identified in other countries, novel types were also documented. No specificity between genotypes and nature of the pathologic process could be identified. After genetic comparison between strains from different origins, the results may suggest that rabbit, bovine and human S. aureus isolates are not clonally related, suggesting that specific host-dependent pathogenic factors may have evolved independently in these species. These differences indicate that a rational and effective strategy to control infections caused by rabbit-specific isolates may be advantageous.  相似文献   

13.
The 16S rRNA genes from eight isolates of Renibacterium salmoninarum with different origins and dates of isolation were sequenced to evaluate the possibility to construct a diagnostic PCR system with target sites within this gene. The sequences were found to be identical but for one single position in one of the isolates, and two regions with an adequate number of nucleotide differences as compared to closely related species were identified. Species-specific fluorescent PCR primers complementary to these regions were constructed as well as oligonucleotides for DNA preparation by sequence capture. A mimic molecule was constructed to be used as an internal control. The PCR was specific and allowed the detection of DNA equivalent to 1-10 R. salmoninarum genomes per reaction. The DNA preparation with sequence capture and analysis by PCR with a mimic was found to be a reliable method for analysis of kidneys from fish with BKD. The amount of PCR inhibiting substances present in the tissue was reduced, and the relevant DNA was concentrated in the capture step. Furthermore, the use of the mimic molecule in the system assured that false negative results could be identified.  相似文献   

14.
In a previous study we investigated pulsed-field gel electrophoresis (PFGE) genotype diversity and prevalence of the netB toxin gene in Clostridium perfringens (CP) isolates recovered from a broiler flock (flock 1) affected by necrotic enteritis (NE). In this follow-up work, we examined samples collected before placement of flock 1, to see if NE during rearing could be traced back to the cleaned and empty building or the day-old chicks. Litter from the next flock in the same building (flock 2) was also examined. We detected 25 different PFGE genotypes, five of which were found only in litter from flock 2. Six genotypes which had been found in flock 1 during rearing were detected in samples collected before placement. NetB positive isolates belonging to two of these genotypes had been recovered from NE lesions during rearing, suggesting that virulent strains were transmitted from the cleaned and disinfected broiler house. NetB frequency among isolates from the empty building was 45%, indicating that netB positive strains were prevalent in a building that previously had housed a healthy flock offered in-feed narasin (flock 0). NetB frequency among isolates from litter used by flock 2 was 22%, indicating that netB positive strains were present in the environment of a 14-days-old healthy flock offered in-feed narasin. Two prevalent genotypes were consistently either netB negative or netB positive. However, the presence of genotypes represented by both negative and positive isolates may suggest that the gene can spread horizontally among different CP strains.  相似文献   

15.
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   

16.
Twenty-nine Staphylococcus sciuri strains isolated from free-living insectivores and rodents were comparatively analysed for their biochemical capacities and their SmaI macrorestriction patterns. The 29 S. sciuri isolates represented 21 different biotypes and 22 different SmaI macrorestriction types. This observation confirmed that S. sciuri isolates obtained from insectivores and rodents living in natural environments constituted a heterogeneous population. Cluster analysis revealed that the macrorestriction patterns and the biochemical profiles matched in some cases. However, S. sciuri isolates that exhibited the same or closely related biochemical profiles were also found to be associated with different macrorestriction patterns. Analysis of the 29 S. sciuri isolates for their plasmid content and their sensitivity to antimicrobial agents showed that most of the isolates were plasmid-free and susceptible to all antimicrobial agents tested.  相似文献   

17.
Clinical specimens of small animals (n=869) were screened for the occurrence of methicillin-sensitive and methicillin-resistant Staphylococcus aureus (MSSA; MRSA) during routine microbiological examinations, and results were confirmed by a multiplex PCR strategy. The genetic relatedness of all mecA-positive S. aureus isolates was further investigated by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), PCR for Panton-Valentine leukocidine genes (PVL) and staphylococcal cassette chromosome mec-typing (SCCmec). A total of 61 S. aureus isolates were found during a 20-month period of investigation, 27 (44.3%) of them harbouring the mecA gene for methicillin-resistance. The majority of MRSA were isolated in specimens from dogs (n=18) and cats (n=4). One guinea pig and one rabbit were found to be positive for an MRSA infected site. Similarly, three exotic animals, a turtle, a bat and a parrot, were found to be infected with MRSA. PFGE and MLST analysis revealed a certain genotype ("A" and "A-1") dominating the isolate collection (23 of 27). Furthermore, one isolate showed homologous PFGE pattern to the German epidemic strain Barnim ("BE") and another one ("BE-1") was considered to be closely related. A third genotype ("B") was detected in two cases. Two different sequence types (ST) were identified among the 27 MRSA isolates. PFGE type "A" and both strains related to the Barnim epidemic strain were assigned to ST22, whereas ST239 was associated to PFGE profile "B". The present data show that certain MRSA genotypes are capable of infecting a wide spectrum of small and exotic animals, especially in clinical facilities.  相似文献   

18.
The aims of this study were to determine the existence of pvl gene, some toxin genes, and mecA gene in Staphylococcus aureus strains isolated from sheep milk and to examine antimicrobial resistance profiles in staphylococci from sheep and goats' milk. The milk samples were collected from 13 different small ruminant farms in Kirikkale province from February to August 2009. A total of 1,604 half-udder milk samples from 857 ewes and 66 half-udder milk samples from 33 goats were collected. Staphylococcus spp. were isolated and identified from the samples. Toxin genes and mecA gene among S. aureus strains were determined by PCR. Antimicrobial susceptibility of staphylococci was examined by the disk diffusion method on Mueller-Hinton agar, and interpreted according to the Clinical Laboratory Standards Institute (CLSI) guidelines. The prevalence of subclinical intramammary infection in both ewes and goats was 5.2%. The most prevalent subclinical mastitis agents were coagulase-negative staphylococci and S. aureus with prevalences 2.8% (n:46) and 1.3% (n = 21), respectively. The prevalence of resistances in isolated Staphylococcus spp. to penicilin G, tetracycline, erythromycin, gentamicin, and enrofloxacin were found as 26.9% (18), 7.5% (5), 6.0% (4), 3.0% (2), and 1.5% (1), respectively. Only 3 of the 21 S. aureus ewe isolates (13.4%) were shown to harbor enterotoxin genes being either seh, sej or sec. However, fourteen (66.6%) of the 21 S. aureus isolates had pvl gene while none of the isolates harbored mecA gene. In conclusion, Staphylococci were shown to be the most prevalent bacteria isolated from subclinical mastitis of ewes and goats and these isolates were susceptible to most of the antibiotics. In addition, S. aureus strains isolated from ewes were harboring few staphylococcal enterotoxin genes. However, Panton–Valentine leukocidin produced by S. aureus could be an important virulence factor and contribute to subclinical mastitis pathogenicity.  相似文献   

19.
Zhang S  Zhao L  Wang X  Zhang D  Zhao J  Zhang G 《Avian diseases》2011,55(3):476-479
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20.
Staphylococcal colonization was compared in healthy dogs and in dogs with atopic dermatitis. Bacterial swabs were collected from the nasal mucosa, ear and perineum of 43 healthy and 24 atopic dogs and also from potentially infected skin lesions of the atopic dogs. Coagulase positive staphylococcal isolates were identified to the species level. At the time of this study Staphylococcus intermedius was considered a single species but has since been recognized as comprising at least three species with canine isolates believed to belong to Staphylococcus pseudintermedius . Of atopic dogs, 87.5% were colonized with S. intermedius compared to only 37.2% of healthy dogs. The ear was the only carriage site that showed any significant difference in S. intermedius isolation between healthy and atopic dogs. The perineum represented the most frequently colonized mucosal site for both groups. Sampling the nasal mucosa alone identified 71.4% of atopic and 37.5% of healthy S. intermedius carriers. Inclusion of a perineal swab identified 100% of atopic and 93.8% of healthy carriers. S. intermedius was isolated from all the lesional sites sampled from atopic dogs. Significantly fewer dogs were colonized by Staphylococcus aureus than S. intermedius , and there was no significant difference between S. aureus colonization of atopic and healthy dogs. S. aureus was not recovered from any lesions in atopic dogs. The results show that S. intermedius carriage is more prevalent in atopic dogs compared to healthy dogs and that to identify staphylococcal carriers both the nasal mucosa and the perineum should be sampled.  相似文献   

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