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1.
The occurrence of staphylococci and enterococci expressing increased resistance to erythromycin (ERY) and, in particular, to macrolide-lincosamide-streptogramin B (MLS(B) ) antibiotics was investigated in dairy cattle, pigs and turkeys. Three hundred rectal (cloacal) swabs of each animal species were examined. A total of 120 and 71 staphylococci and enterococci, respectively, with increased resistance to ERY were identified. These were most frequent in turkeys (42.3% of positive animals), followed by pigs and dairy cattle (6.7% and 6.0% of positive animals, respectively). Similarly, MLS(B) -resistant isolates colonized predominantly turkeys (29.7% of animals), while their occurrence in pigs and dairy cattle was only sporadic (0.8% of animals). At least one of the erm genes encoding for MLS(B) resistance was found in 56.7% and 69.0% of staphylococci and enterococci, respectively. The erm(C) gene prevailed in staphylococci while the erm(B) gene was predominant in enterococci. Macrolide efflux genes msr(A) and msr(C) were also frequent in staphylococci and enterococci, respectively. Macrolide inactivation gene mph(C) occurred mainly in staphylococci. In staphylococci, methicillin resistance was rarely detected (7.5% of isolates), but resistance to telithromycin (ketolides) was frequent in both staphylococci and enterococci (89.2% and 47.9% of isolates, respectively). This study showed that turkeys represent an important source of ERY (MLS(B) )-resistant cocci. In addition, resistance to ketolides was also frequent.  相似文献   

2.
Fifty-six Staphylococcus aureus isolates recovered between 1998 and 2003 from 31 rabbit farms with and without problems of chronic staphylococcosis, were screened for resistance to enrofloxacin, erythromycin, gentamicin, lincomycin, neomycin, penicillin and tetracyclines using the agar dilution test. For penicillin, a disk diffusion test was also performed. The detection of tetP(B), tet(K), tet(L), tet(M), tet(O), tet(T), tet(W), erm(A), erm(B), erm(C) and mec(A) genes was done via a PCR assay. Four isolates showed resistance to erythromycin and lincomycin. These isolates were positive for the erm(C) gene in the PCR. Eleven strains were resistant to tetracyclines and all harboured the tet(K) gene. In the agar dilution test, five isolates showed resistance to penicillin, whereas in the disk diffusion test 12 isolates showed resistance. None of these 12 resistant isolates carried the mec(A) gene. Only one strain showed resistance to gentamicin, and all strains were susceptible to enrofloxacin and neomycin. This study demonstrates that resistance to antimicrobial agents in S. aureus isolates originating from rabbits is relatively rare compared to resistance in S. aureus isolates originating from other animals and humans.  相似文献   

3.
A collection of 77 Staphylococcus intermedius isolates from dogs and cats in Switzerland was examined for resistance to erythromycin. Resistance profiles for 14 additional antibiotics were compared between erythromycin-resistant and susceptible isolates. A resistance prevalence of 27% for erythromycin was observed in the population under study. Complete correlation between resistance to erythromycin, and to spiramycin, streptomycin, and neomycin was observed. The erythromycin-resistant isolates all had a reduced susceptibility to clindamycin when compared to the erythromycin-susceptible isolates. Both constitutive and inducible resistance phenotypes were observed for clindamycin. Ribotyping showed that macrolide-aminoglycoside resistance was randomly distributed among unrelated strains. This suggests that this particular resistance profile is not related to a single bacterial clone but to the horizontal transfer of resistance gene clusters in S. intermedius populations. The erythromycin-resistant isolates were all carrying erm(B), but not erm(A), erm(C), or msr(A). The erm(B) gene was physically linked to Tn5405-like elements known as resistance determinants for streptomycin, streptothricin, neomycin and kanamycin. Analysis of the region flanking erm(B) showed the presence of two different groups of erm(B)-Tn5405-like elements in the S. intermedius population examined and of elements found in Gram-positive species other than staphylococci. This strongly suggests that erm(B) or the whole erm(B)-Tn5405-like elements in S. intermedius originate from other bacterial species, possibly from enterococci.  相似文献   

4.
From 1996 to 2001 a total of 467 Staphylococcus hyicus isolates from exudative epidermitis (EE) in pigs in Denmark were examined for susceptibility to 13 different antimicrobial agents. The presence of selected genes encoding macrolide (erm(A), erm(B) and erm(C)), penicillin (blaZ), streptogramin (vat, vga, vga(B), vat(B), vat(D) and vat(E)), streptomycin (aadE) and tetracycline resistance (tet(K), tet(L), tet(M) and tet(O)) were determined in selected isolates.The occurrence of erythromycin resistance increased from 33% in 1996 to a maximum of 62% in 1997 and decreased to 26% in 2001. Resistance to sulphametazole increased from 17% in 1996 to 30% in 1998 but has since decreased to 4% in 2001. Resistance to trimethoprim increased to 51% in 1997 and decreased to 21% in 2001. Resistance to tetracycline (21-31%) remained relatively constant during 1996-2000, but increased to 47% in 2001. Resistance to penicillin (54-75%) streptomycin (33-53%) and tetracycline (21-47%) remained relatively constant over the time investigated.All 48 penicillin resistant isolates examined contained the blaZ gene and 40 (85%) of the streptomycin resistant isolates the aadE gene. It was not possible to detect any streptogramin resistance gene in four streptogramin resistant isolates. Of the 55 erythromycin resistant isolates examined, five contained erm(A), 13 erm(B), 35 erm(C) and two both erm(A) and erm(C). The presence of erm(B) was confirmed by hybridization to plasmid profiles in all 13 PCR-positive isolates. Of 52 tetracycline resistant isolates examined, two contained tet(L), 38 tet(K) and 12 both tet(K) and tet(L).  相似文献   

5.
Recent reports suggest that methicillin-resistant strains of Staphylococcus schleiferi subspecies coagulans are now commonly isolated from dogs. Given the association of a potentially mobile SCCmec type IV element with lysogenic phage-encoded Panton Valentine Leukocidin (PVL) toxin genes in community-acquired methicillin-resistant Staphylococcus aureus strains we hypothesized that methicillin-resistant S. schleiferi ssp. coagulans strains may also encode PVL toxin genes. Forty S. schleiferi ssp. coagulans strains isolated from companion animals were studied. Susceptibility to oxacillin was determined by broth microdilution and all isolates were screened by PCR for the presence of the mecA gene. SCCmec typing was performed on 14 isolates. A real-time PCR assay was developed for the detection of the PVL genes using a SmartCycler. Pulsed-field gel electrophoresis (PFGE) was performed to determine whether S. schleiferi ssp. coagulans strains were homogeneous. Twenty-eight of the 40 isolates (70%) were resistant to oxacillin and 26/28 possessed the mecA gene by PCR. SCCmec IV was identified in seven strains; the other seven isolates were not typable by this technique. All 40 strains were negative for the PVL toxin gene. PFGE showed a heterogeneous population and 13 different profiles were determined. In conclusion, this study showed that PVL toxin genes were not detected in a heterogeneous population of methicillin-resistant S. schleiferi ssp. coagulans strains isolated from companion animals.  相似文献   

6.
OBJECTIVE: To isolate and characterize erythromycin-resistant methylase genes in multiple-antibiotic resistant staphylococci isolated from milk samples. ANIMALS: 300 lactating cows. PROCEDURE: 23 erythromycin-resistant staphylococci were isolated from milk samples of 300 lactating cows. The prevalence of erythromycin-resistant methylase (erm) genes, ermC and ermA genes, and the multicomponent macrolide efflux pump in staphylococci msrA genes were identified and characterized by use of multiplex polymerase chain reaction (PCR), Southern hybridization, restricted fragment length polymorphism (RFLP) analysis, and dot-blot hybridization. RESULTS: Biochemical characterization indicated that 3 of 23 (13%) isolates were coagulase-positive Staphylococcus aureus, and the rest were coagulase-negative. Multiplex PCR resulted in amplification of a 520-base pair (bp) region of the ermC gene from the cell lysates of a strain of S simulans M-21 and S sciuri M-28. The ermC gene in both isolates was found on a 3-kilobase plasmid. The ermA gene was found on the chromosome of 21 isolates, and 6 RFLP patterns were observed. None of the isolates harbored the msrA gene. CONCLUSIONS: Erythromycin-resistant Staphylococcus spp isolated from milk samples of lactating cows may serve as reservoirs of erm genes homologous to those described in human isolates. However, the chromosomal insert patterns and prevalence of these genes, the sizes of plasmids harboring the genes, and the number of inserts of the genes (copy number) may differ from that of human isolates.  相似文献   

7.
分析河南、陕西分离的14株鸡杆菌(Gallibacterium)之间的进化关系,及gyrB基因序列比较在该菌进化分析中的作用。PCR扩增鸡杆菌分离株的gyrB、16SrRNA和rpoB3个看家基因,PCR产物纯化后直接测序。将鸡杆菌分离株、国外参考株的3个看家基因序列进行比较分析,用Phylip 3.67软件构建进化树。结果表明,14株鸡杆菌与鸭源鸡杆菌(Gallibacterium anatis)模式株间的相似性为96.3%～98.0%(gyrB)、97.7%～99.6%(16SrRNA)和97.7%～99.0%(rpoB);14株鸡杆菌与鸡杆菌复合群1(Gallibacterium genomosp.1)参考株间的相似性为88.8%～89.9%(gyrB)、96.2%～97.5%(16SrRNA)和92.6%～93.6%(rpoB)。基于3个看家基因序列的进化分析,均显示14株鸡杆菌和鸭源鸡杆菌模式株形成单独的一个群。14株鸡杆菌分离株均属于鸭源鸡杆菌种;在3个看家基因位点,鸡杆菌河南株与陕西株之间、鸡杆菌输卵管炎病鸡分离株与健康鸡分离株之间均无明显遗传上的差异;gyrB基因序列分析可用于鸡杆菌分离株的种类鉴定,且对14株鸡杆菌与复合群1参考株的区别能力优于另外2个看家基因。  相似文献   

8.
The presence of the flaA, cadF, cdtB and iam genes of Campylobacter spp. was determined with the PCR method. The materials to investigate were 56 C. jejuni and 23 C. coli strains isolated from clinical samples (children and domestic animals). It was found that all of the Campylobacter spp. isolates from children with diarrhoea and domestic animals had cadF gene, responsible for adherence. The flaA gene was present in all Campylobacter spp. isolates derived from children and cats. Occurrence of flaA gene was confirmed in 100% of C. jejuni strains obtained from dogs. The high prevalence of the cdtB gene associated with toxin production was observed in this study (100%-Campylobacter spp. isolates obtained from dogs and cats, 97.9%-Campylobacter spp. isolates from children). The isolates showed a wide variation for the presence of iam gene. The lowest prevalence (23.5%) was detected in Campylobacter spp. obtained from dogs. The highest rates of iam detection (91.6%) were revealed in C. coli isolates from children.  相似文献   

9.
Domestic farm animals represent an important reservoir of infection for Shiga toxin-producing Escherichia coli (STEC). Nevertheless the bacterial factors required to colonise these hosts are poorly defined. In this study, the prevalence of a recently described fimbrial gene cluster, lpfO113, among human and animal isolates of STEC was investigated. lpfO113 has been shown to play a role in the adherence of STEC O113:H21 to epithelial cells. Here the presence of the lpfAO113 gene (predicted to encode a major fimbrial subunit) was examined by PCR in E. coli of serogroups O157 and O26 isolated from pigs (n=38), cattle (n=10), and humans (n=9). In addition, we tested for several other genetic virulence markers including Shiga toxin (stx), intimin (eae), the translocated intimin receptor (tir), EHEC-hemolysin (ehx) and F18 fimbriae (fedA). Overall 45 of the 57 strains (79%) possessed the lpfAO113 gene as determined by the presence of a 573 bp PCR product. Moreover, there was a close correlation between the presence of the lpfAO113 marker and the absence of the eae gene. lpfAO113 was found in all of pig isolates, suggesting a possible role in colonisation of the porcine host. In addition, several E. coli strains isolated from pigs had two fimbrial gene markers, fedA and lpfAO113. lpfAO113 was not present in strains of E. coli O157:H7 as described previously. Overall these results show that lpfAO113 is widely distributed among eae-negative E. coli isolates and thus may represent an important adherence factor in this group of pathogens.  相似文献   

10.
动物源性链球菌红霉素耐药基因的分布   总被引：6，自引：1，他引：6  
致病性链球菌可导致人和动物的各种化脓性疾病、肺炎、乳腺炎、败血症等，且部分致病性链球菌是重要的人畜共患病病原，对人畜健康均造成极大危害，已引起高度重视。大环内酯类抗生素作为青霉素药物的替代药物是治疗致病性链球菌感染的有效药物。国内外对人医重要的链球菌诸如肺炎球菌、化脓性链球菌的研究表明，临床分离株对大环内酯类抗生素的耐药率较高，  相似文献   

11.
乳房链球菌对克林霉素耐药基因的定位   总被引：3，自引：0，他引：3  
采用试管稀释法和纸片法测定9株乳房链球菌对克林霉素的耐药性，通过PCR反应检测克林霉素的耐药性基因，并进行测序比较。发现克林霉素对乳房链球菌的抗菌活力较强，克林霉素耐药基因同时存在于乳房链球菌的染色体和质粒上。  相似文献   

12.
The genetic variability of a gene coding for an outer membrane lipoprotein (omlA) was used to develop a PCR typing system for Actinobacillus pleuropneumoniae. Sequence differences in the middle region of the gene divided the A. pleuropneumoniae serotypes in five distinct groups. Group I included serotypes 1, 9, 11 and 12 (omlA l), Group II consisted of serotypes 2 and 8 (omlA II), Group III included serotypes 3, 6 and 7 (omlA III), Group IV (omlA IV) consisted of serotype 4 and Group V of serotypes 5a, 5b and 10 (omlA V). The sequence differences were utilized to construct PCR primers specific for each group, except of Group IV, as the amplicon of serotype 4 could be separated from Group III by size. Together with a PCR apx typing system, the omlA PCR typing system could discriminate the majority of A. pleuropneumoniae serotypes of biovar 1 except of serotypes 1, 9 and 11 and serotypes 2 and 8. The PCR typing system was tested on 102 field strains of A. pleuropneumoniae isolated from lungs of diseased pigs. The serotyping results of the investigated field strains were in agreement with the apx and omlA gene patterns found in the reference strains of the bacteria, with the exception of the omlA gene of five strains of serotype 8. To examine the apx and omlA gene pattern of tonsil isolates, the PCR typing system was tested on a total of 280 A. pleuropneumoniae field strains isolated from tonsils of pigs. Agreement between serotyping and DNA typing was found in 96% of the isolates using the apx gene patterns and in 89% of the isolates using the omlA gene. The same serotype specific apx/omlA gene pattern was thus found in the majority of the tonsil isolates and in isolates from diseased lungs. Most of the differences in the omlA gene were found in 18 tonsil isolates of serotype 12. The omlA/apx PCR typing system described in the present study makes it possible to determine the type specificity of the majority of A. pleuropneumoniae isolates by simple PCR technique and enables phenotype independent characterization of isolates non-typable by serotyping.  相似文献   

13.
The prevalence of qnr genes was investigated in veterinary clinical isolates of Escherichia coli in Guangdong province, China, and the aac (6')-Ib gene and the mutations in QRDRs of gyrase and topoisomerase IV were examined in qnr-positive strains. A total of 232 E. coli strains isolated from pig and poultry were screened for the presence of the qnrA, qnrB and qnrS genes by PCR and sequencing. The aac (6')-Ib gene was detected in qnr-bearing strains by PCR and sequencing. For all strains carrying qnr, MICs for six quinolones were determined. Mutations within the gyrase and topoisomerase were analyzed by PCR and sequencing for all the QRDRs of gyrA, gyrB, parC and parE. Among 232 E. coli isolates, 14 (6%) isolates were positive for the qnr gene, including one for qnrB, 13 for qnrS, but no qnrA was identified in this population. Detection of the aac (6')-Ib gene showed that one qnrS-positive isolate from pig and one qnrB-positive isolate from duck carried aac (6')-Ib gene, and both were the cr variant allele of aac (6')-Ib. All of the 14 isolates had MICs of ciprofloxacin more than 0.25 mg/L. Mutations in the QRDR of gyrA mutations were observed in 5 (35.7%) of the 14 strains. Three fluoroquinolone-resisting strains showed one mutation S83L of gyrA, while one S83I. One high-level resistance strains harboured gyrA S83L and A87N of gyrA. A singe mutation in site 58 of parC was detected in 3 (21.4%) strains. None mutations were found in QRDRs of gyrB and parE. The emergence of qnr genes in veterinary clinical E. coli isolates is described for the first time. This is also the first report of aac (6')-Ib-cr gene in E. coli isolates from food-producing animals.  相似文献   

14.
The distribution of many genes encoding virulence and virulence life-style (VL-S) factors in Brachyspira (B.) hyodysenteriae and other Brachyspira species are largely unknown. Their knowledge is essential e.g. for the improvement of diagnostic methods targeting the detection and differentiation of the species. Thus 121 German Brachyspira field isolates from diarrhoeic pigs were characterized down to the species level by restriction fragment length polymorphism analysis of the nox gene and subsequently subjected to polymerase chain reaction detecting VL-S genes for inner (clpX) and outer membrane proteins (OMPs: bhlp16, bhlp17.6, bhlp29.7, bhmp39f, bhmp39h), hemolysins (hlyA/ACP, tlyA), iron metabolism (ftnA, bitC), and aerotolerance (nox). For comparison, B. hyodysenteriae reference strains from the USA (n=7) and Australia (2) were used. Of all genes tested only nox was detected in all isolates. The simultaneous presence of both the tlyA and hlyA/ACP was restricted to the species B. hyodysenteriae. The hlyA infrequently occurred also in weakly hemolytic Brachyspira. Similarly to tlyA and hlyA all B. hyodysenteriae strains contained the ferritin gene ftnA which was also found in two Brachyspira intermedia isolates. OMP encoding genes were present in B. hyodysenteriae field isolates in rates of 0% (bhlp17.6, bhmp39h), 58.1% (bhlp29.7), and 97.3% (bhmp39f). Since the study revealed a high genetic heterogeneity among German B. hyodysenteriae field isolates differentiating them from USA as well as Australian strains, targets for diagnostic PCR were limited to the nox gene (genus specific PCR) as well as to the species specific nox(hyo) gene and the combination of hlyA and tlyA which allow to specifically detect B. hyodysenteriae.  相似文献   

15.
OBJECTIVE: To evaluate sensitivity and specificity of a multiplex polymerase chain reaction (PCR) assay for simultaneous detection of Rhodococcus equi and differentiation of strains that contain the virulence-associated gene (vapA) from strains that do not. SAMPLE POPULATION: 187 isolates of R equi from equine and nonequine tissue and environmental specimens and 27 isolates of bacterial species genetically or morphologically similar to R equi. PROCEDURE: The multiplex PCR assay included 3 gene targets: a universal 311-bp bacterial 16S ribosomal RNA amplicon (positive internal control), a 959-bp R equi-specific target in the cholesterol oxidase gene (choE), and a 564-bp amplicon of the vapA gene. Duplicate multiplex PCR assays for these targets and confirmatory singleplex PCR assays for vapA and choE were performed for each R equi isolate. An additional PCR assay was used to examine isolates for the vapB gene. RESULTS: Results of duplicate multiplex and singleplex PCR assays were correlated in all instances, revealing high specificity and reliability (reproducibility) of the vapA multiplex assay. Of the pulmonary isolates from horses with suspected R equi pneumonia, 97.4% (76/78) yielded positive results for vapA. Seven of 50 (14%) human isolates of R equi yielded positive results for vapA. Six human R equi isolates and 1 porcine isolate yielded positive results for vapB. No isolates with vapA and vapB genes were detected. CONCLUSIONS AND CLINICAL RELEVANCE: The multiplex PCR assay is a sensitive and specific method for simultaneous confirmation of species identity and detection of the vapA gene. The assay appeared to be a useful tool for microbiologic and epidemiologic diagnosis and research.  相似文献   

16.
为了解福州动物园动物细菌耐药现状,选用肠球菌为指示菌,采用琼脂平板筛选法(ADSP法)筛选高水平耐庆大霉素肠球菌(HLGRE)。根据美国临床实验室标准化协会(CLSI)推荐的微量肉汤稀释法测定耐药菌株对6种抗菌药物的耐药性,用PCR法对分离出的不同来源的高水平耐氨基糖苷类肠球菌进行菌种鉴定。从动物园圈养野生动物共分离出78株HLGRE,不同动物来源的分离率不同,其中草食动物HLGRE分离率最低,占55.56%;肉食动物HLGRE分离率最高,占84.38%。药敏试验结果显示,不同动物来源的HLGRE均对红霉素和土霉素的耐药率最高,分别为100%和96.1%,对氨苄西林和万古霉素的耐药率最低。  相似文献   

17.
The aim of this study was to investigate the resistance to fluoroquinolones and compound Chinese medicine, and control colibacillosis in fur-bearing animals.14 E.coli strains isolated from diseased fur-bearing animals were detected by PCR for the fluoroquinolone-resistant gyrA gene,and then the PCR fragment of gyrA gene was cloned,sequenced and analyzed for homology.Afterwards,the fragment was labeled with digoxigenin as DNA probe for dot-blot hybridization detection.The resistance to compound Chinese medicine was detected by Oxford-cup tests.The results demonstrated that the positive rates of PCR and dot-blot hybridization were 57.1% and 50.0%,respectively.Only 28.6% of the E.coli strains were resistant to compound Chinese medicine.The results indicated that the resistance to fluoroquinolones in E.coli strains from fur-bearing animals was severe,however,the isolates were much more sensitive to compound Chinese medicine.The results would provide basis for control of colibacillosis of fur-bearing animals.  相似文献   

18.
本试验旨在了解毛皮动物源大肠杆菌的耐药性,有效控制毛皮动物细菌病的发生.针对14株分离自毛皮动物的大肠杆菌,采用PCR方法检测氟喹诺酮类耐药基因gyrA的携带情况,并对扩增得到的gyrA基因进行克隆测序和同源性分析;进一步针对gyrA基因制备地高辛标记的核酸探针,使用斑点杂交检测大肠杆菌对氟喹诺酮类药物的耐药情况;使用牛津杯法检测了大肠杆菌分离株对复方中药的敏感性.结果显示,PCR检出gyrA基因的阳性携带率为57.1%,斑点杂交检出耐氟喹诺酮类大肠杆菌的阳性率为50.0%,对复方中药的耐药率为28.6%.结果表明,毛皮动物对氟喹诺酮类药物的耐药性非常严重,对中药表现较高的敏感性,研究结果将为临床毛皮动物大肠杆菌病的防制提供依据.  相似文献   

19.
食品动物源产超广谱β-内酰胺酶大肠杆菌的流行状况调查   总被引：1，自引：1，他引：0  
本研究旨在了解产超广谱β-内酰胺酶(ESBLs)大肠杆菌和CTX-M型耐药基因在食品动物的流行状况。对分离自养殖场的1273株大肠杆菌(健康动物源755株,患病动物源518株),采用双纸片协同试验筛选ESBLs阳性菌,并通过PCR法和基因测序鉴定阳性菌CTX-M型的基因型。1273株食品动物源大肠杆菌中筛选出产ESBLs阳性菌181株,阳性率为14.2%,其中患病动物阳性率比健康动物高,分别为19.9%和10.3%。151株(83.4%)产ESBLs大肠杆菌中检测到CTX-M型基因,占所有食品动物源大肠杆菌的11.8%,其中以CTX-M-9G为主,阳性率为79.5%(120/151),远高于CTX-M-1G的携带率25.8%(39/151),其中8株同时携带了CTX-M-1G和CTX-M-9G。产ESBLs的大肠杆菌在食品源动物中流行普遍,CTX-M是产ESBLs阳性菌中的主要流行基因型。  相似文献   

20.
The objective of this study was to design a multiplex PCR assay to identify Mannheimia haemolytica, Mannheimia glucosida and Mannheimia ruminalis. The multiplex PCR included primer sets HP, amplifying a DNA region from an unknown hypothetical protein, Lkt and Lkt2, amplifying different regions of the leukotoxinD gene, and 16S to amplify universal bacterial sequences of the 16S rRNA gene. Based on positive amplification, isolates were delineated as M. haemolytica (HP, Lkt, 16S), M. glucosida (HP, Lkt, Lkt2, 16S), or M. ruminalis (HP, 16S). The validity of the assay was examined against 22 reference strains within the family Pasteurellaceae and 17 field isolates (nasal) that had been collected previously from feedlot cattle and tentatively identified as M. haemolytica based on morphology and substrate utilization. Additionally, 200 feedlot cattle were screened for M. haemolytica using multiplex PCR. Forty-four isolates from 25 animals were identified as M. haemolytica. The PCR assay positively identified all M. haemolytica, as confirmed by phenotypic tests and clustering based upon cellular fatty acid methyl ester (FAME) profiles. Selected nasal isolates that exhibited evidence of haemolysis, but were M. haemolytica-negative based on PCR, were also confirmed negative by phenotypic and FAME analyses. The multiplex PCR assay required no additional phenotypic tests for confirmation of M. haemolytica, within the group of bacteria tested.  相似文献   

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