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1.
Coagulase-negative Staphylococcus (CNS) isolates (n=168) obtained from milk from heifers and dairy cows were screened for minimum inhibitory concentration (MIC) to antimicrobials used commonly for mastitis therapy. Of the 10 CNS species included in the study, the predominant species were Staphylococcus chromogenes (n=61), Staphylococcus epidermidis (n=37), Staphylococcus hyicus (n=37), and Staphylococcus simulans (n=16). The majority of CNS was susceptible to ampicillin, oxacillin, cephalothin, and ceftiofur. Erythromycin and pirlimycin were also very effective in vitro inhibitors of CNS. The only exception was observed with S. epidermidis. Of 37 S. epidermidis evaluated, 13 (35%) exhibited efflux-based resistance to erythromycin (> or =16 microg/ml) encoded by msrA and one isolate carried ermC encoding ribosomal methylase-based resistance to both erythromycin (> or =64 microg/ml) and pirlimycin (> or =64 microg/ml). A total of 17 S. epidermidis, 11 S. chromogenes, and one S. hyicus exhibited phenotypic resistance to ampicillin (> or =0.5 microg/ml). Constitutive beta-lactamase production was observed in all ampicillin resistant isolates except 4 S. epidermidis that exhibited inducible beta-lactamase production. Induced beta-lactamase production was also observed in 13 S. epidermidis that were phenotypically susceptible to the entire MIC panel. All isolates that produced beta-lactamase either constitutively or by induction carried blaZ. S. epidermidis (n=12, 32%) that were resistant to methicillin (oxacillin > or =0.5 microg/ml) carried low affinity penicillin-binding protein encoded by mecA. Most multi-drug resistant (MDR) S. epidermidis (> or =2 resistance genes) were resistant to ampicillin, erythromycin and methicillin. All except one MDR S. epidermidis had icaAB, which encodes for polysaccharide intercellular adhesion. Based on pulsed field gel electrophoresis, MDR S. epidermidis were closely related genotypically, and were isolated from different cows on the same farm suggesting clonal dissemination. Bovine S. epidermidis share antimicrobial resistance patterns and virulence determinants of strains observed in human infections. Studying CNS at the species level can provide valuable information about species-specific differences that can be vital data for effective mastitis therapy and management.  相似文献   

2.
为了查明我国奶牛乳房炎无乳链球菌对抗生素耐药情况,指导临床合理用药,从我国部分地区奶牛场采集的临床型奶牛乳房炎病乳中分离鉴定出无乳链球菌115株,采用K-B纸片法测定了这些菌株对抗生素的耐药情况。结果表明,无乳链球菌对目前临床上使用的大部分抗生素,如头孢唑啉、头孢噻肟、丁胺卡那霉素、卡那霉素、庆大霉素、四环素、强力霉素、麦迪霉素、林可霉素、氟苯尼考、多黏菌素B、环丙沙星、氟哌酸、氨苄青霉素/舒巴坦、头孢噻肟/棒酸和头孢他啶/棒酸均比较敏感;但对青霉素G、氨苄青霉素、链霉素、恩诺沙星、阿莫西林/棒酸和复方新诺明等有一定耐药性,其耐药率达50%～100%。  相似文献   

3.
【目的】研究内蒙古地区部分奶牛养殖场乳房炎生鲜乳样本及环境样本致病菌种类和耐药性,为乳房炎的防控提供临床用药指导和参考。【方法】采用平板划线法对内蒙古地区4个规模化养殖场468份(乳房炎生鲜乳样本199份,乳房炎奶牛饲养环境样本269份)样本进行细菌分离培养,采用形态学观察、革兰氏染色镜检以及16S rDNA测序对分离出的细菌进行鉴定,且对引发乳房炎的主要致病菌进行药敏性试验。【结果】高盐甘露醇培养基上呈现出小、白且偏黄色的菌落,经16S rDNA测序比对,与金黄色葡萄球菌高度相似的菌株共56株,分离率为11.97%;在伊红-美蓝培养基上呈现出黑紫色泛有金属光泽的菌落,经16S rDNA测序比对,与大肠杆菌高度相似的菌株共44株,分离率为9.40%。在199份生鲜乳样本中,金黄色葡萄球菌和大肠杆菌的分离率最高,分别为21.11%和17.09%;在269份环境样本中,金黄色葡萄球菌和大肠杆菌的分离率分别为5.20%和3.72%。药敏试验结果显示,金黄色葡萄球菌对青霉素、磺胺异噁唑、氨苄西林、阿莫西林/克拉维酸的耐药性相对较高,耐药率分别为90.63%、78.13%、75.00%、68.75%;对庆大霉素、环丙沙星、复方新诺明的敏感性较高。大肠杆菌对氨苄西林、头孢噻吩、磺胺异噁唑存在明显耐药性,耐药率分别为100%、94.29%、45.71%;对链霉素、卡那霉素、庆大霉素、多粘菌素E、美罗培南、阿莫西林/克拉维酸以及利福昔明表现出较高敏感性。【结论】内蒙古地区引发奶牛乳房炎的主要致病菌为金黄色葡萄球菌、大肠杆菌;金黄色葡萄球菌对青霉素、磺胺异噁唑、氨苄西林、阿莫西林/克拉维酸的耐药性相对较高;大肠杆菌对氨苄西林、头孢噻吩、磺胺异噁唑存在明显的耐药性。  相似文献   

4.
Swab specimens obtained from skin lesions of 45 cats were cultured bacteriologically for staphylococci. Thirty-two staphylococcal isolates were recovered from 30 cats and were biotyped, using biochemical tests contained in a staphylococcal identification system. Of 23 isolates considered coagulase-positive, 16 were identified as Staphylococcus aureus, 5 as S intermedius, and 2 as S hyicus. Of 9 isolates considered coagulase-negative, 6 were identified as S simulans, 2 as S epidermidis, and 1 as S xylosus. Antimicrobial susceptibility tests were done on all staphylococcal isolates, using a disk-diffusion method. Staphylococcal isolates were susceptible to clavulanic acid-amoxicillin, cloxacillin, cephalothin, chloramphenicol, gentamicin, erythromycin, and trimethoprim-sulfamethoxazole. Resistance to penicillin G, ampicillin, and tetracycline was frequent.  相似文献   

5.
Strains of Staphylococcus species isolated from bovine mastitic milk at 66 dairy farms in Japan during the period from November 1988 to May 1989 were identified, and examined for their drug susceptibility and beta-lactamase production in order to clarify an epidemiological aspect of bovine mastitis caused by staphylococci. The results of bacteriological identification showed that the most predominant species was S. xylosus. Other major species isolated were S. aureus, S. sciuri and S. hyicus. Thirty-eight (71.7%) isolates of S. xylosus, 21 (45.7%) of S. aureus and 5 (71.4%) of S. epidermidis were positive for beta-lactamase production. Most of the beta-lactamase-producers of S. aureus were classified as high producers, although all of the beta-lactamase-positive S. xylosus isolates remained to be low producers. All isolates of S. aureus were sensitive to methicillin and cloxacillin at 6.25 micrograms/ml and 1.56 micrograms/ml, respectively, and none of methicillin-resistant S. aureus were detected. Isolates of other species were considered to be susceptible to 6 beta-lactams, in contrast to human isolates, but antibacterial activities of penicillin G and ampicillin were affected more strongly by beta-lactamase than those of methicillin, cloxacillin, cefazolin and cefoperazone.  相似文献   

6.
A total of 522 strains belonging to streptococci, enterococci and staphylococci isolated from sub-clinical and clinical cases of bovine mastitis from the west littoral region of Uruguay were analysed for their susceptibility to several antimicrobial agents. The susceptibility patterns were studied by agar disk diffusion methods (ADDM) and broth micro-dilution to determine the minimum inhibitory concentration (MIC). The concentration that inhibits 90% (MIC90) of the analysed strains reported in micrograms per millilitre, for Staphylococcus aureus were > 8, 8, < or = 0.5, < or = 4, < or = 1, < or = 0.5, > 64, < or = 0.25, 0.5, < or = 1 and < or = 1 to penicillin, ampicillin, oxacillin, cephalotin, gentamicin, erythromycin, oxitetracycline, enrofloxacin, trimethoprim/sulfamethoxazole, neomycin, and clindamycin, respectively. Coagulase-negative staphylococci (CNS) had different values for penicillin (4) and ampicillin (2), while the other antimicrobial agents had the same MIC90 values as reported for S. aureus. The MIC90 values for streptococci were 0.12, 0.25, < or = 4, 16, < or = 0.25, 0.5, 0.25 for penicillin, ampicillin, cephalotin, gentamicin, erythromycin, oxytetracycline and trimethoprim-sulfamethoxazole, whereas MIC90 for enterococci were 4, 4, 4, < or = 0.5, 2, > 8 for penicillin, ampicillin, gentamicin, erythromycin, oxytetracycline and trimethoprim-sulfamethoxazole, respectively. Of 336 strains of S. aureus, 160 (47.6%) were resistant to penicillin. For 41 CNS strains, 10 (27%) presented penicillin-resistance. All the streptococcal strains were susceptible to penicillin, while 3 (7%) of the 43 enteroccocal strains were resistant. Non significant statistical differences were found between the results obtained by ADDM and broth micro-dilution for classifying bacterial isolates as susceptible or resistant according to the National Committee of Clinical Laboratory Standards.  相似文献   

7.
For control of the udder health status of milk sheep the minimal inhibitory concentration of mastitis causing pathogens to 12 different chemotherapeutics was determined by means of Sensititre microplate method. 73 staphylococci- and 8 streptococci-strains was examined. Following staphylococci-strains were found: S. aureus (11), S. epidermidis (34), S. chromogenes and S. xylosus (6 each), S. hyicus and S. warneri (each 5) as well as S. sciuri and S. simulans (3 each). MIC-values to penicillin, amoxycillin and ampicillin of 2 penicillinase-positive S. aureus-strains were more than 4.0 micrograms/ml. The remaining isolates and the major part of coagulase-negative staphylococci displayed MIC-values up to 1.0 microgram/ml to beta-lactamantibiotics except cloxacillin. Against cephalosporines, cephalexin excluded, and aminoglycosides very low MIC-values concerning staphylococci were observed. In case of spiramycin MIC-levels more or less than 8.0 micrograms/ml were determined. Streptococci exhibited MIC-values in the range of 0.06 to 0.5 microgram/ml against beta-lactamantibiotics with exclusion of cloxacillin, cefoperazone and cefquinome and spiramycin as well.  相似文献   

8.

Background

The goal of this study was to estimate the distribution of udder pathogens and their antibiotic resistance in Estonia during the years 2007-2009.

Methods

The bacteriological findings reported in this study originate from quarter milk samples collected from cows on Estonian dairy farms that had clinical or subclinical mastitis. The samples were submitted by local veterinarians to the Estonian Veterinary and Food Laboratory during 2007-2009. Milk samples were examined by conventional bacteriology. In vitro antimicrobial susceptibility testing was performed with the disc diffusion test. Logistic regression with a random herd effect to control for clustering was used for statistical analysis.

Results

During the study period, 3058 clinical mastitis samples from 190 farms and 5146 subclinical mastitis samples from 274 farms were investigated. Positive results were found in 57% of the samples (4680 out of 8204), and the proportion did not differ according to year (p > 0.05). The proportion of bacteriologically negative samples was 22.3% and that of mixed growth was 20.6%. Streptococcus uberis (Str. uberis) was the bacterium isolated most frequently (18.4%) from cases of clinical mastitis, followed by Escherichia coli (E. coli) (15.9%) and Streptococcus agalactiae (Str. agalactiae) (11.9%). The bacteria that caused subclinical mastitis were mainly Staphylococcus aureus (S. aureus) (20%) and coagulase-negative staphylococci (CNS) (15.4%). The probability of isolating S. aureus from milk samples was significantly higher on farms that had fewer than 30 cows, when compared with farms that had more than 100 cows (p < 0.005). A significantly higher risk of Str. agalactiae infection was found on farms with more than 600 cows (p = 0.034) compared with smaller farms. The proportion of S. aureus and CNS isolates that were resistant to penicillin was 61.4% and 38.5%, respectively. Among the E. coli isolates, ampicillin, streptomycin and tetracycline resistance were observed in 24.3%, 15.6% and 13.5%, respectively.

Conclusions

This study showed that the main pathogens associated with clinical mastitis were Str. uberis and E. coli. Subclinical mastitis was caused mainly by S. aureus and CNS. The number of S. aureus and Str. agalactiae isolates depended on herd size. Antimicrobial resistance was highly prevalent, especially penicillin resistance in S. aureus and CNS.  相似文献   

9.
The occurrence and phenotypic, and genotypic properties of 24 Staphylococcus isolates from canine dermatitis were investigated. The predominant staphylococcal species was Staphylococcus intermedius. The other species such as Staphylococcus chromogenes, Staphylococcus sciuri, Staphylococcus aureus, Staphylococcus saprophyticus, Staphylococcus epidermidis, and Staphylococcus capitis were only occasionally isolated. The study showed low level biochemical diversity among S. intermedius isolates. Resistance to antibiotics was frequently observed, with 87.5% of the isolates showing resistance to at least one drug. The most active antimicrobial agents against all staphylococci were amoxicillin/clavulanic acid, cephalexin and gentamicin. Resistance to carbenicillin, amoxicillin, ampicillin, cephadroxil, erythromycin, clinadmaycin and neomycin was common. No correlation was observed between antibiotic resistance and plasmid profile. PFGE analysis revealed a high degree of genetic polymorphism of S. intermedius, even among isolates collected in a restricted area over a short time.  相似文献   

10.
Specimens obtained from pyogenic skin lesions of 210 dogs were culturally examined for staphylococci. A total of 215 isolates of staphylococci were biotyped, using the biochemical tests contained in a commercial staphylococcal identification system. Of 201 coagulase-positive isolates, 197 were identified as Staphylococcus intermedius, 3 as S aureus, and 1 as S hyicus. Of 14 coagulase-negative isolates, 5 were identified as S epidermidis, 5 as S xylosus, 3 as S simulans, and 1 as S hominis. Antimicrobial susceptibility tests were done on all staphylococcal isolates, using the standard disk-diffusion method. Staphylococcus intermedius isolates were susceptible to cephalothin, methicillin, and gentamicin. Resistance to ampicillin, penicillin G, and tetracycline was frequent. Antibiotic resistance was not associated with the depth of skin infection. Resistance to ampicillin, penicillin, tetracycline, and trimethoprim-sulfamethoxazole was not associated with previous antibiotic use. Increased resistance to chloramphenicol, clindamycin, and erythromycin was associated with previous antibiotic therapy. Antimicrobial susceptibilities of the other Staphylococcus species isolated are reported, but the small numbers of these species precluded making meaningful comparison with S intermedius.  相似文献   

11.
试验旨在研究无乳链球菌的生物学特性,为防治无乳链球菌引起的奶牛乳房炎提供理论依据。根据细菌分子生物学分离鉴定无乳链球菌,参考GenBank登录的牛源无乳链球菌16S rRNA、菌属特异性cfb （CAMP因子）、毒力基因和耐药基因序列,运用Oligo 6.0和Primer Premier 5.0软件设计14对引物,建立PCR快速检测方法,并进行20种常见抗生药物的耐药试验。结果显示,试验成功鉴定出17株牛源无乳链球菌,毒力基因与NCBI上已报道的无乳链球菌相应序列具有高度同源性,均≥99%;共检测到6种耐药基因;分离菌株对青霉素、红霉素、林可霉素、克林霉素、万古霉素、氨苄西林、新生霉素、磺胺异噁唑的耐药率均较高,耐药率依次为100.0%、94.1%、94.1%、94.1%、94.1%、82.3%、82.3%和47.1%,对青霉素严重耐药;而对氨基糖苷类、四环素类、头孢菌素类、喹诺酮类耐药率均较低,耐药率分别为15.7%、14.7%、7.7%和3.9%。本研究结果表明,建立的PCR快速检测方法灵敏可靠,云南地区无乳链球菌已对部分β-内酰胺类、大环内酯类、磺胺类等抗生素出现多重耐药性。  相似文献   

12.
Attempts were made to identify 900 species of staphylococci or micrococci recovered from samples of bovine milk examined for mastitis pathogens. The presence and identity of haemolysins was recorded together with results of disc diffusion antibiotic sensitivity tests. The occurrence of clinical mastitis was also noted and somatic cell counts (SCC) were performed on milk samples which were normal in appearance. Eight hundred and thirty-one coagulase positive staphylococci were obtained, of which 810 were S. aureus and 21 were S. intermedius. Of 65 coagulase negative staphylococci the species of 19 could not be determined by the identification systems used. The remainder were identified as S. hyicus sub sp. hyicus (1), S. hyicus sub sp. chromogenes (19), S. haemolyticus (17), S. hominis (3), S. epidermidis (4), S. capitis (1) and either S. hominis or S. warneri (1). Four other isolates could not clearly be assigned to the genus Staphylococcus or Micrococcus and were designated irregular strains. No micrococci were identified. The presence of alpha, beta, or delta haemolysins occurring singly or in various combinations was identified in 98.3% of coagulase positive staphylococci and in 60% of coagulase negative staphylococci. Epsilon haemolysin was detected in 47.6% of the coagulase negative staphylococci and in 9.5% of S. intermedius. All staphylococci were sensitive to tetracycline (30 microg), novobiocin (1.6 microg), nafcillin (30 microg), methicillin (10 microg) and cephalothin (30 microg) and variable numbers of each species were sensitive to penicillin (2 iu) and streptomycin (10 microg). One non-identified species of coagulase negative staphylococcus was sensitive to erythromycin (0.4 microg) the remaining staphylococci were resistant. Each of the four irregular strains was sensitive to erythromycin and novobiocin. Clinical mastitis was associated with 30.6% of coagulase positive staphylococci, 15.3% of coagulase negative staphylococci, and two of the four irregular strains (50%). Subclinical mastitis as determined by SCC of 500 x 10(3) or greater was associated with 92.7% of coagulase positive and 37.5% of coagulase negative staphylococci.  相似文献   

13.
The possibility of adherence of Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli or Streptococcus agalactiae to the epithelium of the mammary gland was investigated by inoculating them into this gland of mice. S. aureus, S. epidermidis and E. coli did not adhere to alveolar epithelium in suckling or non-suckling mice. S. agalactiae adhered to alveolar epithelium in non-suckling mice but adhesion was not sufficiently strong to withstand suckling. Bacterial adherence probably does not play a significant role in the establishment of mastitis by these organisms.  相似文献   

14.
从患乳房炎和子宫内膜炎奶牛的奶或子宫黏液中分离菌株,鉴定后选取金黄色葡萄球菌105株、表皮葡萄球菌20株、大肠埃希氏菌20株、链球菌38株(其中停乳链球菌8株,无乳链球菌30株)和牛源多杀巴氏杆菌5株,在体外用重组溶葡萄球菌酶、苯唑西林、氨苄西林、庆大霉素按照微量肉汤稀释法进行了杀菌试验。结果表明,重组溶葡萄球菌酶对奶牛乳房炎和子宫内膜炎分离的金黄色葡萄球菌和表皮葡萄球菌具有良好抑杀效果,对链球菌(包括无乳链球菌和停乳链球菌)和牛源多杀巴氏杆菌具有一定的抑杀效果,对大肠杆菌作用较差;苯唑西林、氨苄西林、庆大霉素都有一定量的耐药菌株产生,而重组溶葡萄球菌酶对苯唑西林、氨苄西林、庆大霉素耐药菌株同样具有良好抑杀效果。  相似文献   

15.
This study was carried out to determine the prevalence of coagulase-negative staphylococci in clinical and subclinical mastitis in commercial and small-scale farms in Zimbabwe. Thirty five quarter milk samples from clinical mastitis cases and 371 quarter milk samples from cows with subclinical mastitis were cultured for bacterial pathogens. The most frequent pathogens isolated in clinical mastitis were the enteric bacteria (31.4%), followed by coagulase negative staphylococci (22.9%) and then Staphylococcus aureus (17.1%), whereas in subclinical mastitis S. aureus (34.2%) and coagulase-negative staphylococci were (33.2%) the most common. Bacillus species were only isolated in milk samples from subclinical mastitis. Coagulase-negative staphylococci were observed in mixed infections with other bacteria in only 2.2 of the 406 milk samples from clinical and subclinical mastitis where they were isolated together with Bacillus species in 6 of the 9 mixed infection cases. About 95% of the milk samples from which 131 coagulase-negative staphylococci were isolated had correspondingly high somatic cell counts. The coagulase-negative staphylococci isolated most frequently were S. chromogenes (7.9%), S. epidermidis (7.4%) and S. hominis (5.9%). They were all associated with high somatic cell counts. All the coagulase-negative staphylococci isolates were susceptible to cloxacillin and erythromycin, and more than 90% of the isolates were susceptible to neomycin, penicillin and streptomycin. The highest resistance was to tetracycline (17.6%), followed by lincomycin (13.7%). About 8% of the isolates were resistant to both penicillin and streptomycin.  相似文献   

16.
通过细菌形态学和细菌生化特性,分离和鉴定了新疆地区患子宫内膜炎的21头奶牛子宫分泌物中的病原菌分别为蜡样芽孢杆菌(24.5%)、非溶血性链球菌(18.4%)、大肠杆菌(14.3%)、溶血性链球菌(10.2%)、表皮葡萄球菌(10.2%)、金黄色葡萄球菌(10.2%)、胎儿弯曲菌(10.2%)和不动杆菌等.其中革兰氏阳性菌检出率较高(73.5%).子宫内膜炎病原菌以单一菌株感染为主(47.6%).采用Kirby-Barer法测定了鉴定菌株对13种抗微生物药的体外药物敏感性.链球菌、大肠杆菌和葡萄球菌对氨苄西林不敏感,而对卡那霉素和庆大霉素敏感性较高;大肠杆菌对青霉素和氨苄西林全部耐药(100%),对四环素和多西环素耐药率较高(均为83.3%);溶血性链球菌对青霉素和四环素全部耐药,对链霉素耐药率为80%;相对而言,表皮葡萄球菌和金黄色葡萄球菌的耐药率较低;氟喹诺酮类对各种分离菌株比较敏感.  相似文献   

17.
This study characterized the antimicrobial susceptibility of 221 Staphylococcus aureus isolated from various species, and 60 canine Staphylococcus pseudintermedius isolated from 1986 through 2000 at the Western College of Veterinary Medicine (WCVM). Resistance of S. aureus was most common to penicillin (31%) and tetracycline (14%); resistance of S. pseudintermedius to penicillin was present in 8% and to tetracycline in 34% of isolates. Resistance to trimethoprim/sulfamethoxazole was only seen among S. pseudintermedius, and there was no resistance to amoxicillin/clavulanate, ampicillin/sulbactam, cephalothin, amikacin, gentamicin, enrofloxacin, chloramphenicol, or rifampin among any isolate. Inducible clindamycin resistance was found in both S. aureus and S. pseudintermedius, highlighting the need for careful interpretation of culture and susceptibility test results. There were significant differences in the minimum inhibitory concentrations of penicillin, ciprofloxacin, enrofloxacin, clindamycin, erythromycin, chloramphenicol, and tetracycline between avian, bovine, equine, and porcine isolates.  相似文献   

18.
Streptococcal species isolated from dairy cows with clinical mastitis were obtained from mastitis research workers in Florida, Louisiana, New York, Vermont, Washington, and West Virginia. Seventy-one streptococcal isolates were tested, including 39 strains of Streptococcus agalactiae, 21 strains of S dysgalactiae, and 11 strains of S uberis. The minimal inhibitory concentration of erythromycin, lincomycin, oxytetracycline, penicillin, spectinomycin, streptomycin, and tetracycline was determined for each isolate. Differences were not detected among strains with respect to geographic origin. None of the strains was resistant to penicillin. Lincomycin was the next most effective antimicrobial, with only 2 resistant strains of each streptococcal species. There were no differences among the streptococcal species with respect to resistance to either penicillin or lincomycin. Streptococcus uberis was more likely to be resistant to erythromycin than were S agalactiae and S dysgalactiae (P less than 0.02). Streptococcus agalactiae and S uberis had similar distributions for resistance to oxytetracycline, tetracycline, spectinomycin, and streptomycin. Strains of S dysgalactiae were more likely to have intermediate resistance to oxytetracycline and streptomycin than were strains of S agalactiae and S uberis, which were highly resistant to oxytetracycline and streptomycin (P less than 0.001). Differences were not detected among the streptococcal species with respect to resistance to spectinomycin. Resistance to multiple antimicrobials was observed in all streptococcal species tested. Although S dysgalactiae appeared to have a greater percentage of strains (73%) that were resistant to multiple antimicrobials than did S agalactiae (31%) or S uberis (45%), differences were not statistically significant.  相似文献   

19.
Antimicrobial susceptibility data (n = 1501) and bacterial isolates (n = 258) of important bacterial pathogens from animals were collected in collaboration with eight Swiss laboratories from May 1999 to February 2000. Using these data, the antimicrobial resistance situation could be assessed for the following bacterial species: Escherichia coli, Salmonella, Haemophilus parasuis, Actinobacillus pleuropneumoniae, Pasteurella multocida, Mannheimia haemolytica, Bordetella bronchiseptica, Campylobacter jejuni, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus intermedius, Streptococci, and enterococci. Differences in the distribution of resistance between animal species could be evidenced in E. coli and salmonella. Some resistance frequency data were compared with those obtained in 1980. A significant increase of resistance frequency was observed for several antibiotics. This includes in particular an increase of ampicillin, gentamicin, and cotrimoxazole resistance in E. coli. A similar increase was observed in salmonella for ampicillin, streptomycin, sulfonamides, and nalidixic acid. Staphylococci from dogs (S. intermedius and S. aureus) also presented a clear increase of resistance for penicillin, neomycin, sulfonamides, cotrimoxazole, and erythromycin. Finally, a comparison with data from abroad shows that the antibiotic resistance situation in Switzerland is relatively favorable.  相似文献   

20.
为了掌握辽宁地区奶牛乳房炎主要细菌性病原种类及致奶牛乳房炎大肠杆菌药物敏感性特征,本研究选取辽宁地区某大型奶牛场75头临床表现为乳房炎的奶样进行细菌培养与分离,通过生化方法对分离到的细菌进行鉴定,并对分离到的奶牛源大肠杆菌进行体外药物敏感性试验研究。结果发现,该场奶牛乳房炎细菌性病原主要为大肠杆菌、葡萄球菌和链球菌,其检出率分别为58.7%、64.0%和54.7%,存在二重感染和三重感染等混合感染的情况。大肠杆菌药物敏感性试验结果表明,该场分离株对磺胺类药物（耐药率>85%）及氯霉素类药物（耐药率>30%）耐药性较高,对氨苄西林（9.5%）、环丙沙星（9.5%）、头孢噻呋（7.1%）和氧氟沙星（4.8%）比较敏感。上述研究结果为该地区奶牛乳房炎的防制提供可靠的理论依据。  相似文献   

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