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1.
为分析分离自北京地区腹泻犬、健康犬粪便的粪肠球菌的耐药性,研究2种犬粪便来源优势分子型粪肠球菌重要毒力基因携带情况,在中国农业大学教学动物医院收集犬粪便,并分离得到腹泻犬粪便源粪肠球菌45株,健康犬粪便源粪肠球菌32株,采用琼脂稀释法测定分离菌株对12种抗生素的最小抑菌浓度,用多位点序列分型(MLST)技术进行分子分型,并利用PCR方法检测优势分子型粪肠球菌5种不同毒力基因携带情况。结果显示,腹泻犬源和健康犬源粪肠球菌对四环素、多西环素、米诺环素、红霉素、利福平耐药率较高。腹泻犬源分离株对氯霉素、氨苄西林、阿莫西林克拉维酸、呋喃妥因耐药率较低,集中于8.9%～17.8%,对万古霉素不耐药;健康犬源分离株对青霉素、呋喃妥因耐药率较低,分别为4.8%和14.3%,对氨苄西林、阿莫西林克拉维酸、万古霉素不耐药。45株腹泻犬源粪肠球菌共发现15种序列型(ST),优势ST为ST116、ST16、ST179,32株健康犬源粪肠球菌发现18种ST,优势ST为ST16和ST27,2种来源优势ST粪肠球菌agg、gelE、cylB、esp、efaAs毒力基因检出率差异不显著(P0.05)。表明北京地区腹泻犬、健康犬肠道粪肠球菌多重耐药现象严重,需加强抗生素使用的监控和管理;腹泻犬、健康犬肠道粪肠球菌毒力基因携带率差异不显著,都具有向人传播致病性粪肠球菌的风险,兽医临床医护人员和宠物犬饲养人应注意防护。  相似文献   

2.
以Caco-2细胞作为体外模型研究几株乳酸菌的黏附性能及其对大肠杆菌K88和鼠伤寒沙门氏菌的黏附抑制性能。采用荧光标记法评价这几株乳酸菌的黏附性能,并通过竞争、排斥和置换试验检测其对上述2株病原菌黏附的抑制作用。结果表明:1)除了乳酸乳球菌外,其他乳酸菌对Caco-2细胞的黏附率均高于这2株病原菌,且黏附率为乳杆菌(Lactobacillus)>肠球菌>致病菌>乳球菌。2)来源于健康鸡肠道的乳杆菌与分离于人肠道的鼠李糖乳杆菌(Lacto-bacillus rhamnosus)和食果糖乳杆菌(Lactobacillus fructivorans)的黏附率接近。3)大部分乳酸菌菌株能通过置换作用抑制大肠杆菌K88和鼠伤寒沙门氏菌的黏附。结果提示,这几株乳酸菌对肠上皮细胞均有较高的黏附率,尤其是乳杆菌,且它们的黏附有菌属特异性。乳酸菌抑制上述2种病原菌的黏附主要通过置换方式,但没有菌属特异性,且与其自身的黏附力也没有必然的联系。  相似文献   

3.
《中国兽医学报》2016,(1):40-47
通过革兰染色、菌落形态观察、生化分析鉴定、牛津杯抑菌试验、Caco-2细胞黏附试验对分离到的6株乳酸产生菌进行研究。结果显示:经16SrDNA序列测定,比对分析6株乳酸产生菌与鼠李糖乳杆菌、乳酸乳球菌乳亚种、唾液乳杆菌、乳链球菌、哥伦比亚肠球菌和鼠乳杆菌高度同源。6株乳酸菌抑菌试验检测显示:对大肠杆菌、沙门菌、蜡样芽胞杆菌和金黄色葡萄球菌具有很强的抑菌效应,以CM3菌株的抑菌效果最强。同时,这6株乳酸菌对Caco-2细胞均有一定的黏附能力。结果表明:6株番鸭肠道乳酸产生菌能够黏附于肠道模型Caco-2细胞上并具有较强的抑菌活性,但其黏附性能及保护机制还有待进一步研究。  相似文献   

4.
为了从猪粪便中分离出肠球菌,采用6.5%NaCl pH 9.6 TSB和麦康凯血平板两种方法分别对80个健康猪源样品和53个流行性腹泻猪源样品进行检测。结果显示,共分离出115株肠球菌,其中健康猪源肠球菌72株,包括粪肠球菌2株,屎肠球菌30株,其他肠球菌40株,检测率为90%;从流行性腹泻中共分离到43株肠球菌,其中粪肠球菌9株,屎肠球菌29株,其他肠球菌5株,检出率为81.1%,前者方法中其他肠球菌的检出率比较高,后者方法屎肠球菌的检出率比较高。两种方法各有侧重,为分离不同菌种的肠球菌提供依据。  相似文献   

5.
从克鲁伦河流域牧区24个牧民家庭37份乳及乳制品中,分离到16株乳酸球菌,其中嗜热链球菌4株,乳酸乳球菌乳酸亚种5株,其他棉子糖乳球菌、格氏乳球菌、盲肠球菌、鸡肠球菌、屎肠球菌、鸟肠球菌各1株,均属乳酸同型发酵菌,发酵糖的能力也较强.  相似文献   

6.
从克鲁伦河流域牧区24个牧民家庭37份乳及乳制品中，分离到16株乳酸球菌，其中嗜热链球菌4株，乳酸乳球菌乳酸亚种5株，其他棉子糖乳球菌、格氏乳球菌、盲肠球菌、鸡肠球菌、屎肠球菌、鸟肠球菌各1株，均属乳酸同型发酵菌，发酵糖的能力也较强。  相似文献   

7.
猪源大肠杆菌的分离和耐药性监测   总被引：1，自引：0，他引：1  
为了调查猪源大肠埃希氏菌的耐药性,从扬州大学动物医院送检的大肠杆菌病猪中,采取病料进行大肠杆菌的分离培养,共获得16株菌株。通过茵落的细菌形态学观察,革兰氏染色镜检和生化试验,确定分离的细菌为大肠杆菌。应用纸片扩散法对分离的大肠杆菌进行药物敏感性试验,结果表明分离得到的大肠杆菌对茵必治、痈特灵、丁氨卡那较敏感。通过本次试验可知,菌必治可作为送检地区防治致病性犬肠埃希氏菌的首选药物,丁胺卡那作为备选药,而痢特灵作为兽药禁用药由于使用很少,所以细菌对其敏感性较高。  相似文献   

8.
为了解北京市宠物源细菌的抗菌药物耐药情况,2022年,笔者对北京市四个城区的四家宠物医院的犬、猫共计50份样本的肛拭子进行了研究。试验对样品中的大肠杆菌和肠球菌首先进行了分离培养和质谱鉴定,然后采用微量肉汤稀释法分析分离菌株的耐药表型。结果共分离出大肠杆菌25株、肠球菌25株（屎肠球菌14株、粪肠球菌11株）。大肠杆菌耐药率最高的2种抗菌药为四环素和氨苄西林,多重耐药菌占44%;肠球菌耐药情况较严重,粪肠球菌耐药率最高的抗菌药物为磺胺异噁唑,屎肠球菌耐药率最高的抗菌药物为磺胺异噁唑、头孢西丁和红霉素,二者多重耐药菌占分离株总数的100%。综上,北京地区宠物源大肠杆菌、肠球菌的耐药情况较为严峻,且多重耐药现象突出,需要加强对宠物抗菌药使用的监督与管理。  相似文献   

9.
为了解不同动物源肠球菌耐药性,试验选用10种常用抗生素,采用统一材料、方法(KB法)和判断标准[美国临床实验室标准化协会(CLSI)2007年版]对从5种不同动物源(人、狗、鸡、牛、猪)粪便中分离得到的肠球菌进行耐药性检测。结果表明:共分离得到肠球菌646株,包括人源肠球菌146株、狗源肠球菌138株、鸡源肠球菌128株、牛源肠球菌111株、猪源肠球菌123株;各动物源肠球菌对四环素和利福平耐受性偏高,对青霉素G、万古霉素和高浓度庆大霉素耐受性偏低,其中耐万古霉素肠球菌47株,平均耐药率为7%;各动物源肠球菌的耐药性表现为鸡源肠球菌最强,猪源肠球菌、狗源肠球菌、人源肠球菌次之,牛源肠球菌最低。说明滥用抗生素已造成人和畜禽动物肠球菌较为普遍的耐药,应引起临床及畜禽业高度重视。  相似文献   

10.
为了解西昌地区猪源肠外致病性大肠杆菌的耐药情况,本试验对2016～2018年西昌地区21个猪场的106个病猪样本进行了大肠杆菌的分离鉴定和耐药性检测。通过培养特性、染色特点和形态观察以及PCR鉴定、致病性试验,共分离到28株肠外致病性大肠杆菌。采用K-B纸片法进行药敏试验,结果显示28株致病性大肠杆菌对阿莫西林、氨苄西林、强力霉素、四环素、庆大霉素、复方新诺明耐药严重,耐药率高于85%,对阿米卡星和头孢喹肟保持较高的敏感性,耐药率分别为14.3%和10.7%。28株大肠杆菌的多重耐药率高达100%,表明西昌地区猪源肠外致病性大肠杆菌的耐药性强、耐药谱广。  相似文献   

11.
Selected probiotic lactic acid bacteria (LAB) have been shown to elicit positive health effects particularly in humans. Competitive exclusion of pathogens is one of the most important beneficial health claims of probiotic bacteria. The effect of probiotic LAB on competitive exclusion of pathogens has been demonstrated in humans, chicken and pigs. In this study we evaluated the ability of certain LAB strains (Lactobacillus rhamnosus GG, Bifidobacterium lactis Bb12, Lactobacillus pentosus UK1A, L. pentosus SK2A, Enterococcus faecium M74 and E. faecium SF273) to inhibit the adhesion of selected canine and zoonotic pathogens (Staphylococcus intermedius, Salmonella Typhimurium ATCC 14028, Clostridium perfringens and Campylobacter jejuni) to immobilised mucus isolated from canine jejunal chyme in vitro. Adhesion of C. perfringens was reduced significantly by all tested LAB strains, between 53.7 and 79.1% of the control without LAB, the LAB of canine origin yielding the best reduction. The adhesion of S. Typhimurium and S. intermedius were not significantly altered by any of the LAB included in the study. Both enterococci tested significantly enhanced the adhesion of C. jejuni, to 134.6 and 205.5% of the control without LAB. E. faecium may thus favor the adhesion and colonization of C. jejuni in the dog's intestine, making it a potential carrier and possibly a source for human infection. Enhanced C. jejuni adhesion is a new potential risk factor of enterococci. Our results further emphasize the importance of safety guidelines to be established for the probiotics intended for animal use.  相似文献   

12.
Streptococcus faecium was fed to prevent colibacillosis in gnotobiotic pigs. Three strains of Escherichia coli were used. With strain O:K103, 987P:NM in pigs fed S faecium before the E coli challenge exposure, the pigs exhibited less severe diarrhea, recovered earlier, and produced better weight gains than did pigs given E coli only. Escherichia coli strains O157:K88ac:H19 and O8:K87, K88ab:H19 were more virulent. Pigs fed S faecium and challenge exposed with these 2 strains of E coli developed mild diarrhea; however, none of the pigs died, and they continued to eat well and gained weight. Pigs given E coli only developed severe diarrhea and lost weight, and 5 of 8 infected pigs died. Bacterial counts of E coli and S faecium from 3 areas of the small intestine and the cecum were all comparable among experimental groups. Histopathologic examinations demonstrated abundant colonization of the intestinal tract with S faecium. Seemingly, S faecium reduced the toxic effects of E coli and prevented generalized infection and death.  相似文献   

13.
Antimicrobial activities of 139 Enterococcus isolates (48 E. faecium and 91 E. faecalis) obtained from canine feces, boiler meat samples, swine feces, wild waterfowl feces, and human feces were examined against respective bacteria, including Streptococcus pyogenes, Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes, Salmonella Enteritidis, and Escherichia coli. Bacteriocin (BAC) production assay revealed that the antimicrobial activity against at least one of 6 indicator strains (BAC+ phenotype) was found in 51 (37%) isolates (29 E. faecium and 22 E. faecalis). Twenty-four of 46 isolates positive for at least one of the enterocin structural genes (entA, entB, entL50AB, and cylL) showed a BAC+ phenotype. The existence of other enterocins or nonenterocin factors was implied because the BAC+ phenotype was detected in a total of 27 Enterococcus isolates that had none of the enterocin genes tested. The antimicrobial activity against Gram-negative strains (Salmonella Enteritidis and E. coli) was detected in the 6 Enterococcus isolates that had either the entA, entB, entL50AB or cylL genes. Moreover, the proportion of the antimicrobial activity against L. monocytogenes among the cylL-positive E. faecalis isolates showing beta-hemolysis (10/16) was significantly (p<0.01) higher than among those lacking beta-hemolysis (2/15). The results suggested that certain characteristics are likely to be associated with the antimicrobial activity against specific organisms.  相似文献   

14.
The prevalence of strains of Staphylococcus aureus, coagulase-negative (CN) staphylococci, Listeria monocytogenes, Escherichia coli, Enterococcus faecalis, E. faecium and Bacillus cereus, was investigated in 111 bulk milk samples. Staphylococcus aureus was isolated from 38 samples, CN staphylococci from 63 samples, E. coli from 49 samples, E. faecalis or E. faecium from 107 samples, and L. monocytogenes from two samples. Bacillus cereus was not found in any of the samples and three samples were free of any of the selected species. Sensitivity to the anti-microbial drugs amikacin, ampicillin, ampicillin + sulbactam, cephalothin (CLT), cephotaxime, clindamycin, chloramphenicol (CMP), co-trimoxazole, erythromycin (ERY), gentamicin, neomycin, norfloxacin, oxacillin, penicillin, streptomycin (STR), tetracycline (TTC) and vancomycin was tested using the standard dilution technique. Minimum inhibitory concentration (MIC) characteristics (MIC50, MIC90, MIC range) were determined for each microbial species. Resistance against one or more anti-microbial drugs was found in 93% of S. aureus, 40% of CN staphylococci, 73% of E. coli, 88% of E.faecalis, 55% of E.faecium, and one L. monocytogenes strain. Most of the strains, particularly enterococci, were resistant to STR, TTC, and ERY (MIC50 4 microg/ml). A high percentage of staphylococci were resistant to beta-lactam antibiotics. High resistance to CLT was found in 11 strains of E. coli (MIC 256 microg/ml) and strains resistant to CMP (MIC90 16 microg/ml) were detected. The highest numbers of resistance phenotypes were found in E. coil (16) and CN staphylococci (12). Eighteen identical resistance phenotypes were demonstrated in indicator bacteria (E. coli, E. faecalis, E. faecium) and pathogens (S. aureus, CN staphylococci) isolated from the same bulk milk sample. The obtained resistance data were matched against the herd owners' information on therapeutic use of the drugs. This confrontation could not explain the findings of strains resistant to ERY or CMP. Our findings are evidence of selection of resistant strains among not only pathogenic agents, but also among indicator bacteria which can become significant carriers of transmissible resistance genes.  相似文献   

15.
The adhesive capacity of selected enterococci to human, canine and porcine intestinal mucus was investigated in order to select for potential probiotic strains with good adhesive properties for human or animal use. The adhesion to the human intestinal mucus of the tested strains was found to range from log10 3.8 to log10 8.6 cfu per microtitre plate well. The highest adhesion to the human intestinal mucus was found among strains from horse faeces, dog faeces and dog feed. The adhesion to canine mucus was observed to range from log10 3.8 to log10 8.3 cfu/well, with the highest adhesive capacity among strains from dog faeces, horse faeces and dog's feed; on average log10 7.9, 7.3 and 7.0 cfu/well, respectively. Isolates from dogs did not bind at higher levels to canine mucus than to human mucus. A strong correlation was observed for the adhesion to human and canine intestinal mucus (p < 0.0001) and also between porcine and canine or human mucus (p < 0.05 for both). When comparing the adhesion of Enterococcus faecium and E. faecalis, no statistical significant differences were observed for any of the tested mucus types. The tested Enterococcus strains were found to exhibit a strain dependent on in vitro adhesion to human, canine and porcine intestinal mucus and did not exhibit host specificity in their adhesion, though some sources appeared to contain more adhesive strains than others. To our knowledge, this is the first report on the in vivo adhesion to intestinal mucus of a large number of enterococci from different sources.  相似文献   

16.
Pyometra is a potentially life-threatening condition in bitches and is often caused by Escherichia coli infection. Both pathogenic and non-pathogenic E. coli strains commonly carry the genes for type 1 fimbriae that mediate bacterial adhesion onto host epithelium. To investigate whether the type 1 fimbrial adhesin, FimH, facilitates the binding of uropathogenic E. coli to canine endometrium, the fimH gene was insertionally inactivated in a pathogenic E. coli strain. The ability of E. coli to bind to canine endometrial epithelial cells was determined in vitro using canine uterine biopsies. Binding of the fimH mutant was only 0.3% of that of the wild type. Complementation of the mutation restored the phenotype to that of the parent. This study has developed an in vitro model that allows quantitative and qualitative assessment of bacterial binding to canine endometrium and has demonstrated that the fimH gene plays a role in adherence of pathogenic E. coli to canine endometrium.  相似文献   

17.
Escherichia coli is commonly isolated in canine pyometra, but little is known of the virulence factors that may be involved in the precipitation of this disease. The aim of this study was to compare the prevalence of uropathogenic virulence factor (UVF) genes in E. coli isolates from canine pyometra and from feces of healthy bitches to evaluate their role in the pathogenesis of pyometra. E. coli from 23 cases of canine pyometra and from the feces of 24 healthy bitches were analyzed, by polymerase chain reaction, for UVF genes associated with canine and human urinary tract infections (UTIs). The prevalences of UVFs in E. coli from canine pyometra were similar to that in canine and human uropathogenic E. coli. The prevalence of pap was greater (P=0.036) for E. coli from pyometra (52%) than for fecal isolates (21%), and the papGIII allele was present in all pap-containing isolates. The prevalences of genes for alpha-haemolysin and cytotoxic necrotising factor 1 were not significantly higher (P=0.075) in E. coli from pyometra than from feces. The proportion of pyometra strains with >or=3 UVFs was higher (P=0.039) than that of fecal strains, suggesting that possession of >or=3 UVF genes enhances the pathogenicity of the strain. Our findings demonstrate that E. coli associated with canine pyometra are similar to uropathogenic strains, and that operons that encode P fimbriae, alpha-haemolysin and cytotoxic necrotising factor 1 probably enhance the virulence and pathogenicity of the strain in the canine genital tract.  相似文献   

18.
The FimH subunit of type 1 pili mediates adhesion of Escherichia coli to epithelium in different animal hosts. In this study, we sequenced and analyzed the fimH genes of 24 E. coli strains from bovine and porcine clinical cases. The obtained sequences were compared among each other and also with 24 known fimH sequences from avian E. coli strains. This comparison revealed a substantial homology (>99%) among strains from the different animal species origins. Moreover, specific mutations were found, some of which were present more frequently in avian strains or in bovine and porcine strains.  相似文献   

19.
研究嗜酸乳杆菌、禽大肠杆菌O78、大肠杆菌ATCC 25922、鸡白痢沙门氏菌和鼠伤寒沙门氏菌与肉鸡不同肠段粘液糖蛋白的粘附性能,探讨嗜酸乳杆菌对四种病原菌的粘附排斥作用.结果表明,在不同的肠道部位,嗜酸乳杆菌、鸡白痢沙门氏菌和鼠伤寒沙门氏菌与肠粘液糖蛋白的粘附能力不同,而禽大肠杆菌O78、大肠杆菌ATCC 25922在各肠段粘液上的粘附性能相近;在相同的肠道部位,所试菌与肠粘液糖蛋白的粘附能力有差异,其中嗜酸乳杆菌的粘附作用最强;嗜酸乳杆菌对所试病原菌均有不同程度的粘附排斥作用,其中对鸡白痢沙门氏菌的粘附排斥较强,而对大肠杆菌ATCC25922的则较弱.  相似文献   

20.
Seven strains of Escherichia coli, originating from clinical cases of bovine mastitis, and one Salmonella typhimurium control strain were tested for their ability to adhere to, and invade, bovine mammary epithelial cells (MAC-T cells) in vitro. Four of the seven strains were isolated from cows with chronic intramammary infections with recurrent episodes of clinical mastitis and three strains were isolated from single cases of clinical mastitis. Both adhesion and invasion of all strains were dose and time dependent. The four E. coli strains isolated from recurrent cases of clinical mastitis invaded twice as frequently as and three times faster than the strains isolated from single cases of clinical mastitis. By contrast, there was no difference in the amount or speed of adhesion between the two types of strains of E. coli. Adhesion and invasion curves of E. coli resembled a two-step chain reaction, where invasion was the rate-limiting step. Although adhesion and invasion of E. coli has not been demonstrated in vivo yet, the results of the present study may contribute to an understanding of the pathogenesis of chronic intramammary infections caused by E. coli.  相似文献   

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