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1.
The present study was carried out to genotypically characterize Staphylococcus aureus (S. aureus) isolated from bovine mastitis cases. A total of 37 strains of S. aureus were isolated during processing of 552 milk samples from 140 cows. The S. aureus strains were characterized phenotypically, and were further characterized genotypically by polymerase chain reaction using oligonucleotide primers that amplified genes encoding coagulase (coa), clumping factor (clfA), thermonuclease (nuc), enterotoxin A (entA), and the gene segments encoding the immunoglobulin G binding region and the X region of protein A gene spa. All of the isolates yielded an amplicon with a size of approximately 1,042 bp of the clfA gene. The amplification of the polymorphic spa gene segment encoding the immunoglobulin G binding region was observed in 34 isolates and X-region binding was detected in 26 isolates. Amplification of the coa gene yielded three different products in 20, 10, and 7 isolates. The amplification of the thermonuclease gene, nuc, was observed in 36 out of 37 isolates. All of the samples were negative for the entA gene. The phenotypic and genotypic findings of the present strategies might provide an understanding of the distribution of the prevalent S. aureus clones among bovine mastitis isolates, and might aid in the development of steps to control S. aureus infections in dairy herds.  相似文献   

2.
In the present study 13 Arcanobacterium pluranimalium strains isolated from various animal origin could successfully be identified phenotypically by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and genotypically by sequencing 16S rDNA and the pluranimaliumlysin encoding gene pla. The detection of mass spectra by MALDI-TOF MS and the novel genotypic approach using gene pla might help to identify A. pluranimalium in future and might elucidate the role this species plays in infections of animals.  相似文献   

3.
The present study was designed to characterize phenotypically and genotypically nine Arcanobacterium abortisuis strains collected from specimen of pigs in a period of nine years. All nine A. abortisuis strains and A. abortisuis reference strain DSM 19515 displayed a synergistic hemolytic reaction with Staphylococcus aureus β-hemolysin, Rhodococcus equi, and Arcanobacterium haemolyticum indicator strains and showed the typical biochemical properties of this species. The species identity could be confirmed by identification and sequencing of the 16S-23S rDNA intergenic spacer region (ISR), which appeared to be a useful target for genotypic characterization of this bacterial species. The A. abortisuis strains of the present study were isolated from specimen of pigs together with various other bacterial species indicating that the pathogenic importance of this newly described species remains to be elucidated.  相似文献   

4.
A total of 57 bacteria representing eight species of genus Arcanobacterium (A.) were investigated for hemolytic properties on blood agar containing sheep and rabbit blood and for CAMP-like reactions. An enhanced hemolysis on blood agar containing rabbit blood compared to sheep blood could be observed for A. haemolyticum, less pronounced for A. hippocoleae and A. pluranimalium.A synergistic hemolytic reaction with staphylococcal β-hemolysin appeared to be constantly visible for A. hippocoleae, A. pluranimalium and A. pyogenes, with Streptococcus agalactiae for A. phocae and A. haemolyticum, with Rhodococcus equi for A. phocae, A. haemolyticum, A. pluranimalium and A. pyogenes and with A. haemolyticum for A. hippocoleae, A. pluranimalium and A. pyogenes, respectively. A reverse CAMP-reaction in the zone of staphylococcal β-hemolysin could be observed for A. phocae and A. haemolyticum. In addition, a novel CAMP-like reaction could be noted between Psychrobacter phenylpyruvicus, identified by 16S rDNA sequencing, and A. phocae and A. haemolyticum. These synergistic or antagonistic hemolytic properties could possibly be used as additional criteria for identification of bacteria of genus Arcanobacterium.  相似文献   

5.
In the present study 320 milk samples collected from 160 apparently healthy camels of three different locations in Sudan were investigated for the presence of Staphylococcus aureus resulting in the isolation of this bacterial pathogen from 28 milk samples from 24 camels. Twenty-five S. aureus were identified phenotypically and by PCR mediated amplification of species-specific genes or gene segments. Investigation of the S. aureus for toxinogenic potential revealed that three S. aureus strains were positive for the enterotoxin encoding gene sec and the genes seg, sei, sem, sen and seo, representing the egc gene cluster. In addition all 25 S. aureus were positive for the superantigen-like encoding gene ssl7 (set1). Partial sequencing of gene sec of the three S. aureus strains yielded an almost complete sequence identity to the sequence of the sec variant sec2. However, all three sec2 genes of the present study showed a deletion of one base causing a frame shift and a corresponding earlier stop codon.According to the present results, the raw camel milk collected from three locations in Sudan seems to be, at least at this stage, of minor importance as vector causing staphylococcal food poisoning.  相似文献   

6.
Isolation of Arcanobacterium pyogenes from the Porcine Gastric Mucosa   总被引：3，自引：0，他引：3  
Arcanobacterium (Actinomyces) pyogenes is an inhabitant of the mucous membranes of the respiratory and genital tracts of a number of domestic animal species. However, following a precipitating physical or microbial insult, A. pyogenes can become an opportunistic pathogen, associated with suppurative infections. The isolation of A. pyogenes from the bovine ruminal wall indicated that this organism may also inhabit the gastrointestinal tract of, at least, cattle. To determine whether A. pyogenes was also present on the gastric mucosa of a monogastric animal, porcine stomachs were cultured for the presence of this organism. Of 13 stomachs samples. A. pyogenes was isolated from 5 (39%). The identity of the organism was confirmed by PCR with primers specific to the plo gene, which encodes the A. pyogenes haemolytic exotoxin pyolysin. In addition, an isolate from each positive stomach was subjected to 16S rRNA gene sequencing and the identification as A. pyogenes was confirmed. These data indicate that A. pyogenes may be resident on the gastric mucosa of pigs.  相似文献   

7.
In the present study four methicillin-resistant Staphylococcus pseudintermedius (MRSP) strains isolated from a dog (n = 3) and the anterior nares of the dog owner (n = 1) were investigated by conventional and molecular methods. The species identity of the four S. pseudintermedius strains was confirmed by conventional methods, by PCR mediated amplification of S. intermedius/S. pseudintermedius specific segments of thermonuclease encoding gene nuc and by restriction fragment length polymorphism analysis of phosphoacetyltransferase encoding gene pta. Investigation of the four S. pseudintermedius for toxinogenic potential revealed that all four strains were positive for the exfoliative toxin encoding gene siet and the leukotoxin encoding genes lukS, lukF. The oxacillin and penicillin resistance of the four S. pseudintermedius strains could be determined by cultivation of the strains on oxacillin resistant screening agar base, ChromID MRSA Agar and Brilliance MRSA Agar and by multiplex PCR detecting the resistance genes mecA and blaZ. The genetic relatedness of the strains was studied by macrorestriction analysis of their chromosomal DNA using pulsed field gel electrophoresis (PFGE). According to PFGE all four S. pseudintermedius strains represent an identical bacterial clone indicating a cross transmission between the dog and the dog owner.  相似文献   

8.
In the present study, Staphylococcus (S.) hyicus strains isolated in Russia (n = 23) and Germany (n = 17) were investigated for the prevalence of the previously described genes sheta and shetb. Sheta was detected in 16 S. hyicus strains. Sheta-positive strains were mainly found among strains isolated from exudative epidermitis, and frequently together with the exfoliative toxin-encoding genes exhD and exhC. Partial sequencing of sheta in a single S. hyicus strain revealed an almost complete match with the sheta sequence obtained from GenBank. None of the S. hyicus strains displayed a positive reaction with the shetb-specific oligonucleotide primer used in the present study. According to the present results, the exotoxin encoding gene sheta seems to be distributed among S. hyicus strains in Russia and Germany. The toxigenic potential of this exotoxin, which does not have the classical structure of a staphylococcal exfoliative toxin, remains to be elucidated.  相似文献   

9.
In the present study four methicillin-resistant Staphylococcus pseudintermedius (MRSP) strains isolated from a dog (n = 3) and the anterior nares of the dog owner (n = 1) were investigated by conventional and molecular methods. The species identity of the four S. pseudintermedius strains was confirmed by conventional methods, by PCR mediated amplification of S. intermedius/S. pseudintermedius specific segments of thermonuclease encoding gene nuc and by restriction fragment length polymorphism analysis of phosphoacetyltransferase encoding gene pta. Investigation of the four S. pseudintermedius for toxinogenic potential revealed that all four strains were positive for the exfoliative toxin encoding gene siet and the leukotoxin encoding genes lukS, lukF. The oxacillin and penicillin resistance of the four S. pseudintermedius strains could be determined by cultivation of the strains on oxacillin resistant screening agar base, ChromID MRSA Agar and Brilliance MRSA Agar and by multiplex PCR detecting the resistance genes mecA and blaZ. The genetic relatedness of the strains was studied by macrorestriction analysis of their chromosomal DNA using pulsed field gel electrophoresis (PFGE). According to PFGE all four S. pseudintermedius strains represent an identical bacterial clone indicating a cross transmission between the dog and the dog owner.  相似文献   

10.
Using three reference strains of Brachyspira hyodysenteriae (B204, B234, B169), one B. pilosicoli (P43/6/78), one B. murdochii (56-150), one B. intermedia (PWS/A), one B. innocens (B256) and ten Korean isolates, PCR-RFLP analysis of DNA encoding 23S rRNA was performed to establish a rapid and accurate method for characterizing porcine intestinal spirochetes. Consequently, B. hyodysenteriae and B. pilosicoli revealed different restriction patterns; however, the other three species shared the same pattern. These findings are not consistent with a prior report. Differences in 23S rRNA gene sequences, between two B. murdochii strains, 56-150 and 155-20, were observed. These results indicate that 23S rRNA PCR-RFLP could be used as an identification method for pathogenic Brachyspira spp. (B. hyodysenteriae and B. pilosicoli) as well as an epidemiological tool for characterizing spirochetes isolated from swine.  相似文献   

11.
In the present study a Trueperella (Arcanobacterium) bernardiae strain isolated from an anal swab of a three-day-old piglet could be identified phenotypically, by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and genotypically by sequencing the 16S rDNA, the 16S-23S rDNA intergenic spacer region (ISR) and by sequencing the superoxide dismutase A encoding gene sodA. The present study gives the first information about the presence of T. (A.) bernardiae in specimen of animals.  相似文献   

12.
The prevalence, virulence potential, and antibiotic resistance of ophthalmic Staphylococcus pseudintermedius (SP) isolated from dogs were examined. Sixty-seven Staphylococcus species were isolated from ophthalmic samples and surveyed for species-specific sequences in the Staphylococcus intermedius group (SIG) nuclease gene (SInuc), exfoliative toxin gene for SIG (siet), and antibiotic resistance genes (blaZ and mecA). PCR-restriction fragment length polymorphism analysis of the pta gene was also performed. Fifty isolates were identified as SIG strains, all of which were found to be SP. The blaZ gene was detected in 42 of the 50 SP strains and mecA gene was observed in 18 of the 50 SP strains. The 50 SP strains were most susceptible to amoxicillin/clavulanic acid (94%) and chlorampenicol (70%), and highly resistant to tetracycline (94%) and penicillin (92%). It was also found that 16 (88.9%) mecA-positive SP strains were resistant to oxacillin, tetracycline and penicillin. All mecA-positive SP were resistant to more than four of the eight tested antibiotics and therefore considered SP with multi-drug resistance (MDR). Our results indicate a high prevalence of antibiotic resistance genes in ophthalmic SP along with a close relationship between MDR SP strains and the mecA gene. Based on our findings, judicious administration of antibiotics to companion dogs is necessary.  相似文献   

13.
Exotoxins produced by Actinobacillus (A.) pleuropneumoniae (Apx) play major roles in the pathogenesis of pleuropneumonia in swine. This study investigated the role of ApxI in hemolysis and cellular damage using a novel apxIA mutant, ApxIA336, which was developed from the parental strain A. pleuropneumoniae serotype 10 that produces only ApxI in vitro. The genotype of ApxIA336 was confirmed by PCR, Southern blotting, and gene sequencing. Exotoxin preparation derived from ApxIA336 was analyzed for its bioactivity towards porcine erythrocytes and alveolar macrophages. Analysis results indicated that ApxIA336 contained a kanamycin-resistant cassette inserted immediately after 1005 bp of the apxIA gene. Phenotype analysis of ApxIA336 revealed no difference in the growth rate as compared to the parental strain. Meanwhile, ApxI production was abolished in the bacterial culture supernatant, i.e. exotoxin preparation. The inability of ApxIA336 to produce ApxI corresponded to the loss of hemolytic and cytotoxic bioactivity in exotoxin preparation, as demonstrated by hemolysis, lactate dehydrogenase release, mitochondrial activity, and apoptosis assays. Additionally, the virulence of ApxIA336 appeared to be attenuated by 15-fold in BALB/c mice. Collectively, ApxI, but not other components in the exotoxin preparation of A. pleuropneumoniae serotype 10, was responsible for the hemolytic and cytotoxic effects on porcine erythrocytes and alveolar macrophages.  相似文献   

14.
Ticks carry and transmit a remarkable array of pathogens including bacteria, protozoa and viruses, which may be of veterinary and/or of medical significance. With little to no information regarding the presence of tick-borne zoonotic pathogens or their known vectors in southern Africa, the aim of our study was to screen for Anaplasma phagocytophilum, Borrelia burgdorferi, Coxiella burnetii, Rickettsia species and Ehrlichia ruminantium in ticks collected and identified from ruminants in the Eastern Cape, Free State, KwaZulu-Natal and Mpumalanga Provinces of South Africa. The most abundant tick species identified in this study were Rhipicephalus evertsi evertsi (40%), Rhipicephalus species (35%), Amblyomma hebraeum (10%) and Rhipicephalus decoloratus (14%). A total of 1634 ticks were collected. DNA was extracted, and samples were subjected to PCR amplification and sequencing. The overall infection rates of ticks with the target pathogens in the four Provinces were as follows: A. phagocytophilum, 7%; C. burnetii, 7%; E. ruminantium, 28%; and Rickettsia spp., 27%. The presence of B. burgdorferi could not be confirmed. The findings of this study show that zoonotic pathogens are present in ticks in the studied South African provinces. This information will aid in the epidemiology of tick-borne zoonotic diseases in the country as well as in raising awareness about such diseases in the veterinary, medical and tourism sectors, as they may be the most affected.  相似文献   

15.

Background

The bacterial genus Staphylococcus consists of many species that causes infections in pet animals. Antimicrobial resistant staphylococci cause infections that are difficult to treat and they are important from the point of one health perspective. The aim of this study was to determine the prevalence of methicillin-resistant Staphylococcus (MRS) species, including methicillin-resistant S. aureus (MRSA) in diseased pet animals (Group A) and kennel dogs (Group B) in Lithuania and to characterize the isolates according to their antimicrobial resistance.

Results

Twenty-one MRS isolates were obtained from 395 clinical samples (5.3 %; CI 95 % 3.5-8.0) of Group A animals. Sixteen, four and one isolates were from dogs, cats and a pet rabbit, respectively. The mecA gene was present in 20 isolates, whereas one isolate was positive for the mecC gene. Twenty-one MRS isolates (20.0 %; CI 95 % 13.5-28.6) were obtained from the vagina of female dogs (n = 105) (Group B). All isolates carried the mecA gene. Twelve MRS species were isolated of which S. pseudintermedius was the most common (18/42) followed by S. haemolyticus (8/42) and S. lentus (4/42). MRSA was not found. All MRS strains were susceptible to vancomycin, linezolid, daptomycin and quinupristin/dalfopristin. Resistance to tetracycline (16/21), clindamycin (15/21) and erythromycin (14/21) was the most common types of resistance in Group A animals. Three isolates also demonstrated resistance to rifampin. Resistance toward gentamicin (16/21), ciprofloxacin (15/21), macrolides (15/21) and tetracycline (12/21) was the most common in kennel dogs (Group B). The most common genes encoding resistance to antimicrobials (excluding beta-lactams) in isolates from Group A pets were tetK (21/42), aph(3′)-IIIa (11/42) and aac(6'')-Ie-aph(2'''')-Ia (9/42).

Conclusions

A wide range of MRS species were found in pet animals in Lithuania. MRSA was not found.  相似文献   

16.
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.  相似文献   

17.
The prevalence of resistant genes against β-lactams in 119 Aeromonas strains was determined. A large number (99.2%) of the present fish strains were resistant to one or more β- lactams including ceftiofur, amoxicillin-clavulanic acid, ampicillin, piperacillin and cefpodoxime. Among antibiotic resistance phenotypes, the simultaneous resistance to all β-lactams occurred in 25.2% (n=30) of all strains, which consisted of 18 strains of A. dhakensis, 8 strains of A. caviae, 2 strains of A. hydrophila and only one strain of A. veronii. For exploring genetic background of the antibiotic resistances, multiple PCR assays were subjected to detect β-lactamase-encoding genes, blaTEM, blaOXA-B and blaCTX-M. In the results, the blaTEM-1 gene was harbored in all strains, whereas only 3 strains harbored blaOXA gene. In the case of blaCTX-M gene, the gene was detected in 21.0% (25 out of 119) of all strains, which countered with 80% (20 out of 25) of A. dhakensis, 8% (2 out of 25) of A. caviae and 12% (3 out of 25) of A. hydrophila. In addition, most of the blaCTX-M positive strains showed simultaneous resistance to all β-lactams (18 out of 30 strains). In sequence analysis for blaCTX-M genes detected, they were CTX-M group 1-encoding genes including blaCTX-M-33 from 3 eel strains of A. dhakensis. Therefore, A. dhakensis obtained from cultured fish could represent a reservoir for spreading genes encoding CTX-M group 1 enzymes and hence should be carefully monitored, especially for its potential risk to public health.  相似文献   

18.
Trueperella pyogenes can be found as a commensal or pathogenic bacterium among animals causing a variety of pyogenic infections in several species. The agent appears to act primarily as an opportunistic pathogen but may disseminate and produce metastatic abscesses accompanied or not by mastitis, metritis or pneumonia. In this study, 30 porcine T. pyogenes strains were identified by MALDI-TOF MS and 16S rRNA sequencing and further evaluated in relation to their resistance and genetic profiles through broth microdilution and single enzyme AFLP. All strains were susceptible to β-lactams, florfenicol, gentamicin, spectinomycin and tiamulin. The highest resistance rates were observed for sulfonamides, tetracyclines and clindamycin. All isolates could be characterized by SE-AFLP presenting more than 80% of similarity, despite their distinct origins. Four genotypes were detected with the segregation of T. pyogenes ATCC 19411 from Brazilian T. pyogenes strains. No correlation between genotypes and isolates origins and susceptibility profile was observed.  相似文献   

19.
Chlamydia pecorum (designated 22–58) was isolated in 2010 in HmLu-1 cells from the jejunum of a calf which died of necrotizing enterocolitis in Yamaguchi Prefecture, Japan. Immunohistochemical staining identified C. pecorum positive reactions in the jejunal villi. C. pecorum, designated 24–100, was isolated from the feces of a calf with diarrhea in another farm in Yamaguchi Prefecture in 2012. A significant increase in neutralizing antibody titers against C. pecorum was confirmed in paired sera. Nucleotide sequence identities of omp1 genes of the 2 isolates were 100%. The isolates were genetically and antigenically more closely related to C. pecorum Bo/Yokohama strain isolated from cattle with enteritis in Japan than to the other prototype strains, Bo/Maeda isolated from cattle with pneumonia and Ov/IPA isolated from sheep with polyarthritis. These results indicate that C. pecorum strains similar to 22–58 and 24–100 might be endemic in Yamaguchi Prefecture and cause enteric disease in cattle.  相似文献   

20.
Chlamydophila pecorum found in the intestine and vaginal mucus of asymptomatic ruminants has also been associated with different pathological conditions in ruminants, swine and koalas. Some endangered species such as water buffalos and bandicoots have also been found to be infected by C. pecorum. The persistence of C. pecorum strains in the intestine and vaginal mucus of ruminants could cause long-term sub-clinical infection affecting the animal’s health. C. pecorum strains present many genetic and antigenic variations, but coding tandem repeats have recently been found in some C. pecorum genes, allowing C. pecorum strains isolated from sick animals to be differentiated from those isolated from asymptomatic animals. This review provides an update on C. pecorum infections in different animal hosts and the implications for animal health. The taxonomy, typing and genetic aspects of C. pecorum are also reviewed.  相似文献   

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