(1) Background: Bovine viral diarrhea virus (BVDV) is an economically important pathogen affecting cattle worldwide. The genetic diversity of BVDV-2 in buffalo remains poorly understood. This study aimed to elucidate the genomic and antigenic features of GX24, the first BVDV-2b isolate identified from dairy buffalo in China. (2) Methods: The virus was isolated from a rectal swab through three blind passages in MDBK cells and identified through immunofluorescence and RT-PCR. The near-complete genome was sequenced using the Illumina platform and subjected to phylogenetic and recombination analysis. B-cell epitopes and glycosylation sites were predicted using BepiPred-3.0, Epitope1D, DiscoTope-3.0, NetNGlyc-1.0, and NetO-Glyc-4.0. (3) Results: The 12,267-nt GX24 genome (GenBank: PX682047) was classified as BVDV-2b. Recombination analysis detected a putative recombination signal within the NS5A gene involving Chinese BVDV-2b and Italian BVDV-2a strains. Integrative analyses predicted conserved linear and conformational epitope clusters in the N- and C-terminal regions of the E2 protein. Spatial analysis indicated that several epitope residues may be masked by glycan shielding. (4) Conclusions: This study provides the first genomic evidence of a BVDV-2b isolate from dairy buffalo in China, suggesting that BVDV-2b may be present in this population. The putative recombination signal and antigenic characteristics offer valuable insights for the development of diagnostics and vaccine design in the future.

This study isolated and identified two novel Chinese bovine enterovirus (BEV) strains, designated as BEV-GX1901 and BEV-GX1902, from newly transported cattle with the diarrheal feces symptom. We also determined their complete genome sequences (7408 and 7405 nucleotides, respectively) and found both strains have a genome organization analogous to that of picornaviruses. To better understand these two novel strains, a detailed analysis was applied to both strains, including the time of the cytopathic effect (CPE) production, TCID50 measurement, trypsin sensitivity test, ether sensitivity test, chioroform sensitivity test, acid and alkali resistance test, and heat resistance test. Our results showed that these two strains are different in physical and chemical properties. Our study also characterized that BEV-GX1901 and BEV-GX1902, both belonging to the BEV-E4 subtype, were closely related to the Australian strains K2577 and SL305, and the Japanese strain IS1 based on their genome sequences and VP1 region characterizations. It is speculated that this may be related to cattle trade and transportation. Additionally, the gene-by-gene or amino acid-by-amino acid comparison of the two strains found they have differences between their 5'UTR, 3'UTR, VP2, VP1, 2A, 3C, and 3D regions. Our results provide an important update of the virus's presence in China and contribute to a better understanding of the distribution and characterization of BEVs in cattle.

Bovine enterovirus (BEV) is a significant pathogen affecting bovine intestinal health, posing challenges to cattle production and public health. Existing detection methods, such as RT-PCR, RT-qPCR, and LAMP, are time-consuming and dependent on specialized laboratory facilities, highlighting the need for rapid and field-deployable diagnostic tools. In this study, we developed a real-time reverse transcription recombinase-aided amplification (RT-RAA) assay designed for BEV detection, capable of delivering results within 20 min at 39℃. The real-time RT-RAA assay showed no cross-reactivity to other eight pathogens, including BCoV, BVDV, BKV, BRV, BAstV, STEC, FMDV, and PEV. The sensitivity assay revealed that the real-time RT-RAA method could reliably detect a minimum plasmid concentration of 5.50 × 10 ¹ copies/reaction. Clinical validation conducted with 780 field samples revealed performance comparable to those of conventional RT-PCR and RT-qPCR methods, achieving a positivity rate of 23.59 %. The RT-RAA method operates at low temperatures, requires minimal instrumentation, and reduces technical demands, making it ideal for resource-limited settings. Its portability, cost-effectiveness, and robustness position it as a transformative tool for BEV surveillance, enhancing outbreak control, livestock health management, and food safety.

To understand the situation of the main pathogenic bacteria of infectious pneumonia in goats in Guangxi and their resistance to antibiotics,573 samples of disease materials from 2017 to 2021 were detected by pathogen isolation,identification and PCR detection methods,respectively,then the drug sensitivity test was carried out for the main pathogenic bacteria.The results showed that 422 strains of 13 species were isolated and identified,with the infection rates of 75.92％(435/573).The Mycoplasma ovipneumoniae,Escherichia coli and Klebsiella pneumoniae were the main pathogen,with the detection rates of 60.7％(348/573),31.94％(183/573),and 15.2％(87/573),respectively.The infection rates of single infection,double infection,triple infection,quadruple in-fection and quintuple infection among the 435 samples were 52.41％(228/435),26.21％(114/435),11.03％(48/435),6.21％(27/435)and 4.14％(18/435),respectively.Mycoplasma ovipneu-moniae was detected in all the mixed infection samples except the double infection of Escherichia coli and Klebsiella pneumoniae.The results of drug sensitivity test showed that Mycoplasma ovi-pneumoniae was resistant to penicillin G,amoxicillin,cefoxitin,streptomycin,azithromycin and doxycycline,and the resistance rate was 60％to 100％.Escherichia coli was resistant to lincomy-cin,penicillin G and amoxicillin,and the resistance rate was 60％to 100％.Klebsiella pneumoniae was resistant to penicillin G,amoxicillin,doxycycline,flufenicol and lincomycin,and the resistance rate was 70％to 100％.This study showed that there were various pathogens causing goat pneu-monia in Guangxi,and Mycoplasma ovipneumoniae,Escherichia coli and Klebsiella pneumoniae were the main pathogens,and the isolates showed multiple drug resistance.

为了了解广西地区奶牛、肉牛的牛库布病毒(bovine Kobuvirus,BKV)感染情况及分子特征,试验采用RT-PCR的方法对从广西地区采集的奶牛粪便177份、肉牛粪便27份(共204份粪便,其中腹泻牛粪便82份,健康牛粪便122份)进行BKV和其他肠道病毒的检测,分析BKV与其他肠道病毒的共感染情况,以及不同地点和不同季节BKV的感染情况,同时对广西地区BKV的3D基因与国内外30株库布病毒的3D基因进行核苷酸序列同源性分析和遗传进化分析.结果表明:广西地区BKV的感染率为2.94％(6/204),均从腹泻牛粪便中检出,其中奶牛和肉牛的感染率分别为2.26％(4/177)、7.41％(2/27),将6株毒株分别命名为BKV-GXGG01(贵港株)、BKV-GXHC01(河池株)、BKV-GXHC02(河池株)、BKV-GXNN01(南宁株)、BKV-GXNN02(南宁株)和 BKV-GXNN03(南宁株);BKV与牛病毒性腹泻病毒、牛肠道病毒和牛星状病毒存在混合感染,感染率为66.67％(4/6),而单一感染率为33.33％(2/6);6株广西地区BKV毒株的3D基因间的核苷酸序列同源性为93.5％～100％,与国内外Aichivirus B类型参考毒株间的核苷酸序列同源性为89.9％～95.1％,与其他库布病毒参考毒株的核苷酸同源性为35.9％～75.2％;6株广西地区毒株在遗传进化分析中均属于Aichivirus B类型,毒株BKV-GXNN01与日本株K-35、河南株B4、内蒙古株H6和H18、山东株C2、黑龙江株SC7-5、辽宁株H9同属一分支,其余5株毒株BKV-GXGG01、BKV-GXHC01、BKV-GXHC02、BKV-GXNN02、BKV-GXNN03与北京株B1213、泰国株CMB02、日本株U-1同属一分支.说明在广西地区奶牛、肉牛的腹泻病例中均存在BKV感染,推测BKV可能与牛腹泻有关.

Background Extracellular vesicles (EVs) released by helminths play an important role in parasite-host communication. However, little is known about the characteristics and contents of the EVs of Fasciola gigantica, a parasitic flatworm that causes tropical fascioliasis. A better understanding of EVs released by F. gigantica will help elucidate the mechanism of F. gigantica-host interaction and facilitate the search for new vaccine candidates for the control and treatment of fascioliasis.Methods Two different populations of EVs (15k EVs and 100k EVs) were purified from adult F. gigantica culture media by ultracentrifugation. The morphology and size of the purified EVs were determined by transmission electron microscopy (TEM) and by the Zetasizer Nano ZSP high performance particle characterization system. With the aim of identifying diagnostic markers or potential vaccine candidates, proteins within the isolated 100k EVs were analyzed using mass spectrometry-based proteomics (LC-MS/MS). Mice were then vaccinated with excretory/secretory products (ESPs; depleted of EVs), 15k EVs, 100k EVs and recombinant F. gigantica heat shock protein 70 (rFg-HSP70) combined with alum adjuvant followed by challenge infection with F. gigantica metacercariae. Fluke recovery and antibody levels were used as measures of vaccine protection.Results TEM analysis and nanoparticle tracking analysis indicated the successful isolation of two subpopulations of EVs (15k EVs and 100k EVs) from adult F. gigantica culture supernatants using differential centrifugation. A total of 755 proteins were identified in the 100k EVs. Exosome biogenesis or vesicle trafficking proteins, ESCRT (endosomal sorting complex required for transport) pathway proteins and exosome markers, heat shock proteins and 14-3-3 proteins were identified in the 100k EVs. These results indicate that the isolated 100k EVs were exosome-like vesicles. The functions of the identified proteins may be associated with immune regulation, immune evasion and virulence. Mice immunized with F. gigantica ESPs, 15k EVs, 100k EVs and rFg-HSP70 exhibited a reduction in fluke burden of 67.90%, 60.38%, 37.73% and 56.6%, respectively, compared with the adjuvant control group. The vaccination of mice with F. gigantica 100k EVs, 15k EVs, ESP and rFg-HSP70 induced significant production of specific immunoglobulins in sera, namely IgG, IgG1 and IgG2a.Conclusion The results of this study suggest that proteins within the exosome-like vesicles of F. gigantica have immunomodulatory, immune evasion and virulence functions. This knowledge may lead to new strategies for immunotherapy, vaccination and the diagnosis of fascioliasis.

为探究马脓皮病的病原种类及特性,从病马的皮肤脓汁中分离到一株革兰氏阳性菌,经16SrDNA鉴定为金黄色葡萄球菌.经致病性试验、药敏试验、毒力基因和耐药基因等检测.结果显示,以浓度为9.3×108 CFU/mL菌液攻毒小鼠,致死率为40％;分离菌对氧氟沙星等14种药物高敏,具有fnbA、hly/hla、hysA、clfA和clfB等5个毒力基因和norA和gyrA 2个耐药基因.此结果可作为诊治马脓皮病用药参考.

为建立一种快速、准确并可定量检测溶血性曼氏杆菌的环介导等温扩增(LAMP)方法,本研究针对溶血性曼氏杆菌gcp基因设计5条特异性引物,在链置换DNA聚合酶的作用下,优化反应条件,并进行特异性和敏感性试验.特异性检测结果表明,建立的LAMP扩增方法可以在65 min内完成,并具有良好的特异性,检测化脓隐秘杆菌、肺炎克雷伯氏菌、大肠杆菌、牛支原体、鼠伤寒沙门菌、溶血性巴氏杆菌等其他6种常见牛呼吸道综合征致病菌和空白对照(水)时结果均为阴性;灵敏性检测结果表明,建立的LAMP方法检测溶血性曼氏杆菌质粒标准品的最低检出浓度为0.855×10-4 ng/μL;在对临床样品的检测中,本研究建立的LAMP方法对溶血性曼氏杆菌的检出率为52.63％(10/19)大于PCR方法的检出率47.36％(9/19).以上结果表明,本研究建立的基于gcp基因的溶血性曼氏杆菌LAMP检测方法为溶血性曼氏杆菌的快速检测提供了一种新的技术手段,该方法特异性强、灵敏度高、快速简便,可将该方法推广至基层和流行病调查一线,应用于该病原的快速检测.

Abstract Background: Extracellular vesicles (EVs) released by helminths are important in parasite-host communication. However, little is known about the character and contents of Fasciola gigantica EVs. A better understanding of EVs released by F. gigantica will help reveal the mechanism of F. gigantica-host interaction and aid in the search for new vaccine candidates for fascioliasis control. Methods: We used ultracentrifugation to purify two different populations of EVs (15K EVs and 100K EVs) from adult F. gigantica culture media. The morphology and size of the purified EVs were determined by transmission electron microscopy (TEM) and ZETASIZER NANO ZSP. With the aim of identifying diagnostic markers or potential vaccine candidates, proteins within the isolated 100K EVs were analyzed using mass spectrometry-based proteomics (LC-MS/MS). Then, mice were vaccinated with ESPs, 15K EVs, 100K EVs, and rFg-HSP70 combined with alum adjuvant followed by challenge infection with F. gigantica metacercariae. Fluke recovery and antibody levels were used to evaluate vaccine protection. Results: TEM analysis and Nanoparticle tracking analysis indicated successful isolation of two subpopulations of EVs (15K EVs and 100K EVs) from adult F. gigantica culture supernatants using differential centrifugation. A total of 755 proteins were identified in the 100K EVs. Exosome biogenesis or vesicle trafficking proteins, ESCRT pathways proteins,as well as exosome markers, heat shock proteins and 14-3-3, were identified in the 100K EVs. These results indicate that the isolated 100K EVs were exosome-like vesicles. The functions of the identified proteins may be associated with immune regulation, immune evasion, and virulence. Mice immunized with F. gigantica ESP, 15K EVs, 100K EVs, and rFg-HSP70 exhibited a fluke burden reduction of 67.90%, 60.38%, 37.73%, and 56.6%, respectively, compared with the adjuvant control group. The vaccination of mice with F. gigantica 100K EVs, 15K EVs, ESP, and rFg-HSP70 induced significant production of specific IgG, IgG1, and IgG2a in sera. Conclusion: This study suggests that proteins within the exosome-like vesicles of F. gigantica have immunomodulatory, immune evasion, and virulence functions. This knowledge may lead to new strategies for immunotherapy, vaccination, and the diagnosis of fascioliasis.

对2020年8月广西某养羊场送检的1份羊病料采用细菌学和分子生物学方法进行诊断,对分离菌株进行形态学特性、生理生化、16S rDNA测序,结果鉴定为链球菌,应用PCR方法检测到多杀性巴氏杆菌阳性.对分离菌进行药敏试验,结果显示该菌对青霉素、恩诺沙星、氧氟沙星、土霉素、头孢噻呋钠高度敏感.对分离菌进行致病性试验,结果显示该菌有较强的致病性.检测结果表明该病为链球菌与多杀性巴氏杆菌混合感染引起的.

为调查广西不同养殖模式的猪源大肠杆菌耐药表型差异,为合理使用抗菌药物防治猪大肠杆菌病和减缓耐药菌株产生提供参考,采用体外分离培养和体外药敏试验的方法,分离了广西不同养殖模式的猪源大肠杆菌,并进行耐药表型检测和差异性分析.结果显示,大规模养猪场、中小规模养猪场和散养户的猪源大肠杆菌对头孢西丁、头孢他啶和阿米卡星的敏感率高于70％,而对青霉素G、氨苄西林、阿莫西林、利福平、林可霉素和复方新诺明的耐药率均高于90％.大规模养猪场大肠杆菌对恩诺沙星的耐药率极显著低于散养户(P<0.01),对氧氟沙星、庆大霉素和氟苯尼考的耐药率显著低于散养户(P<0.05);中小规模养猪场大肠杆菌对恩诺沙星、强力霉素和氟苯尼考的耐药性显著低于散养户(P<0.05);散养户大肠杆菌对环丙沙星、卡那霉素和壮观霉素的耐药率极显著高于大规模养猪场和中小规模养猪场(P<0.01),而对头孢噻肟的耐药率极显著低于大规模养猪场和中小规模养猪场(P<0.01).大规模养殖场、中小规模养殖场和散养户大肠杆菌的多重耐药指数(MARI)分别为0.62、0.63和0.68.14～23耐,散养户(44株)极显著高于大规模养猪场(30株)(P<0.01),显著高于中小规模养猪场(39株)(P<0.05).结果表明,3种养殖模式的猪源大肠杆菌的耐药情况不同,但均存在严重的耐药问题,且以多重耐药为主.

对广西地区冠状病毒感染引起的牛腹泻病流行情况进行调查,为我国牛冠状病毒病的诊断及流行病学研究提供数据补充.根据GenBank中收录的牛冠状病毒N基因序列,合成检测引物,应用RT-PCR方法对广西地区腹泻牛粪便样品进行检测.此次对广西地区牛腹泻病例的冠状病毒病原调查结果显示,有的地区病毒阳性率达17％,是以往被忽略但实际上应高度重视的重要致病因素.基因序列遗传进化树分析结果显示,牛冠状病毒亲缘关系与地理位置远近呈现正相关,提示应重视贩运、引种带来的病毒传播风险.

为了评估不同微生态制剂对保育猪生长性能及免疫机能的影响,本试验将425头保育猪分成5组,分别添加不同的微生态制剂,试验期42 d.测定保育猪的生长性能、腹泻率、猪繁殖与呼吸综合征病毒(PRRSV)免疫抗体,以及血清中免疫球蛋白IgG、IgA和细胞因子IFN-γ、IL-6、IL-4的含量.结果表明,百合1号(A组)、佳利保(B组)、宝得益(C组)、德林社乳仔猪专用(D组)这4种微生态制剂能够提高保育猪平均末重、平均增重、平均日增重,降低料肉比,A组与对照组相比平均增重、平均日增重显著提高(P＜0.05);A组、B组、D组3种微生态制剂能够降低腹泻率,D组与对照组相比腹泻率显著降低(P＜0.05);A组微生态制剂与对照组相比能够显著提高保育猪PRRSV免疫抗体水平(P ＜0.05);4种微生态制剂均能够提高IgG、IgA、IFN-γ、IL-6和IL-4的含量,A组免疫球蛋白IgG、IgA及细胞因子IL-6含量与对照组相比显著提高(P＜0.05).

对广西规模化猪场分离的120株猪源大肠杆菌进行了头孢菌素类、氟喹诺酮类、氨基糖苷类、四环素类、大环内酯类和酰胺醇类药物耐药表型检测,并通过PCR检测菌株的β-内酰胺酶基因(blaTEM、blaCTX-M)、氟喹诺酮类耐药基因(qnrA、oqxA、oqxB)、氨基糖苷类耐药基因(aac(6')-Ib-cr)、大环内酯类耐药基因(ermB)和酰胺醇类耐药基因(floR)携带情况.耐药性检测结果显示,猪源大肠杆菌对头孢西丁、头孢他啶和阿米卡星具有高敏感率(＞74.0％),而耐药率最高为四环素类84.2％,酰胺醇类为70.8％,氟喹诺酮类为68.9％,氨基糖苷类为49.4％,大环内酯类为43.3％,最低为头孢菌素类31.4％.猪源大肠杆菌最低对1种药物耐药,最高对18种药物耐药,111株为多重耐药菌,以11耐(15株)、8耐(13株)和7耐(12株)为主,共有82种耐药谱型.耐药基因检测结果显示,8个耐药基因的阳性率均≥50.0％,其中阳性率最高为bla TEM基因(91.7％),最低为aac(6')-Ib-cr基因(50.0％),共存在53种基因组合类型,主要为blaTEM+blaCTX-M+qnrA+ oqxA+ oqxB+ aac(6')-Ib-cr+ ermB+ floR(14株,11.7％)和bla TEM+blaCTX-M+qnrA +oqxA +oqxB +ermB+ floR(13株,10.8％).耐药基因和耐药表型相关性分析结果显示,blaTEM和bla CTX-M与大肠杆菌对头孢氨苄耐药情况极显著相关(P＜0.01),bla CTX-M与大肠杆菌对头孢拉啶和头孢曲松耐药情况极显著相关(P＜0.01),qnrA、o qxA、oqxB和aac(6')-Ib-cr基因与大肠杆菌对诺氟沙星、氧氟沙星、恩诺沙星和环丙沙星耐药极显著相关(P＜0.01),aac (6')-Ib-cr基因与大肠杆菌对庆大霉素和卡那霉素耐药极显著相关(P＜0.01),floR基因与大肠杆菌对氟苯尼考耐药情况极显著相关(P＜0.01).本研究结果表明广西规模化猪场猪源大肠杆菌仅对极少数抗菌药物具有较高敏感率,多重耐药情况严重,具有丰富的耐药谱型,携带多种耐药基因且具有复杂的基因组合类型,所携带的耐药基因与其耐药表型具有一定的相关性.

为了找到水牛新生犊牛发生口腔黏膜糜烂的原因,试验观察了临床症状,刮取病牛齿龈糜烂充血增生物和痂皮病料,提取DNA,应用丘疹性口炎病毒(Bovine papular stomatitis virus,BPSV)特异性引物进行PCR扩增及克隆测序,并应用BLAST工具对测序结果进行比对鉴定.结果 表明:新生犊牛临床表现为口腔黏膜糜烂和流涎等症状,PCR扩增获得预期大小的目的片段,所测序列与牛丘疹性口炎病毒基因序列相符,同源性为95.56％.说明该新生犊牛确系丘疹性口炎病毒感染.

为了解广西地区牛、羊的Q热、流产衣原体病、流行性乙型脑炎(简称乙脑)的感染和流行情况,试验采用血清学方法对2017,2018年4个市210个牛场和70个羊场的1 600份牛血清和1600份羊血清进行抗体检测.对牛、羊血清抗体检测结果及三种人兽共患病混合感染情况进行统计分析.结果 表明:牛血清Q热、流产衣原体病和乙脑个体(场群)平均感染率分别为8.50％(40.95％)、38.50％(81.43％)、11.62％(25.24％);羊血清Q热、流产衣原体和乙脑个体(场群)平均感染率分别为18.62％(57.14％)、9.75％(57.14％)、39.38％(85.71％);且牛、羊均出现混合感染的情况,不同地区地区的感染率在统计学上有所差异.说明广西地区牛、羊的Q热、流产衣原体、乙脑感染较为普遍,应对这三种疫病采取积极有效的防控措施.

Mycoplasma bovis(M. bovis) is one of the most significant pathogens in cattle. The aim of this study was to develop a rapid real-time LAMP assay, specific for M. boviswith designed primers targeting the OPPD/F gene. The assay was tested for 1 h at 63°C. The results could be visualized by the addition of calceindye. Real-time LAMP was specific exclusively for M. boviswithout cross-reactivity with other bacteria. The sensitivity of the real-time LAMP was determined to be 2.29×10-3ng/μL of DNA and was 100 times higher than conventional PCR. Lamp assay was conducted on 65 clinical samples to test its usefulness and reliability and compared to the PCR assay results. A concordance of 100% was observed between the two assays. This real-time LAMP assay can be applied by diagnostic laboratories and for field detection of M. bovisinfection

根据GenBank中的大肠杆菌O157∶H7毒力基因rfbE保守序列,应用LAMP引物的设计软件Primer Explorer V4设计针对靶基因rfbE的引物、设计反应程序与体系,成功建立检测致病大肠杆菌的LAMP检测方法.结果 表明,该LAMP方法具有良好的敏感性、特异性及荧光可视化判定效果.该方法对目的菌株纯菌DNA可被检出的最低限可达到1.69×10-4 ng/μL;对9种相关细菌进行LAMP方法检测,大肠杆菌O157∶H7为阳性结果,其余菌株均显示阴性,阳性检出率为100％;优化浊度仪监控条件,反应器加入荧光染料,63℃反应1h后即可观察结果,较PCR方法用时短.结果 表明,该LAMP方法具有操作简便、高效快捷等优势,在食品食源性致病大肠杆菌快速检测监测方面具有较高的实用价值.

为了探索广西地区部分猪场自制微生态制剂的安全性,试验对广西地区三个猪场自制微生态制剂菌液(QC、HK、JX)进行16S rDNA测序、药敏试验、小鼠致病性试验.结果表明:三个猪场自制微生态制剂菌液样品中均含有潜在的致病菌并有不同程度耐药;小鼠灌胃试验中,HK组常规剂量和高剂量下日增重显著低于对照组(P＜0.05),QC组、JX组与对照组之间差异不显著(P＞0.05);小鼠腹腔注射试验中,HK组常规剂量下日增重显著低于对照组(P＜0.05),QC组、JX组高剂量下日增重显著低于对照组(P＜0.05).说明这三种自制微生态制剂存在一定的安全隐患.

为建立快速、灵敏且可定量检测氟苯尼考耐药基因floR的环介导等温扩增方法(LAMP),根据GenBank登录的革兰阴性菌floR基因保守序列,利用PrimerExploerV4设计特异性LAMP引物,成功建立了快速检测氟苯尼考耐药floR基因的LAMP方法.该LAMP检测方法反应温度为63℃,反应时间为60 min,具有可实时监测反应、定量检测出floR基因的拷贝数,以及操作简便的特点,灵敏度高,检测限为6.24×100拷贝,是普通PCR的100倍.用建立的方法检测对氟苯尼考不同敏感性的大肠埃希菌floR基因,结果显示,对氟苯尼考敏感、中介和耐药的菌株均检测到floR基因,其拷贝数与菌株MIC相关,提示floR基因不仅存在于氟苯尼考耐药菌中.所建立的floR基因LAMP检测方法可为floR基因的监测,以及氟苯尼考耐药性产生和传播机制的研究提供新的技术手段.