氟苯尼考对耐氯霉素大肠杆菌菌株的体外药敏试验

目前,氟苯尼考已在亚洲、欧洲、美洲的20多个国家上市,目前我国已生产合成并批准应用于兽医临床。为了证明氟苯尼考对耐氯霉素大肠杆菌菌株的抗菌效果,我们进行了体外药敏试验。旨在为临床用药提供依据。1材料与方法1.1药敏试纸由我院畜禽疾病研究中心提供,批号20021017。1.2试     

氟苯尼考与氯霉素对鸡大肠杆菌病的疗效比较

以试管肉汤2倍稀释法测定氟苯尼考及氯霉素对鸡大肠埃希氏菌的最小抑菌浓度（MIC），然后对实验性鸡大肠杆菌病病鸡进行治疗试验，内服3d,2次／d。结果表明，氟苯尼考及氯霉素对鸡大肠埃希氏菌的最小抑菌浓度分别是3.2μg/mL和1.6μg/mL；以氟苯尼考40mg/kg和氯霉素40mg/kg体重给鸡（每组40只）内服后，对大肠杆菌病的治愈率分别为77．5％和55．0％,而感染对照组的死亡率为95．0％。     

旋光法测定氟苯尼考原料含量

用旋光法测定氟苯尼考含量，并与农业部《兽药质量标准》规定的电位法作对比实验。结果表明氟苯尼考在5mg/ml～25mg/ml浓度范围内，旋光度与浓度呈良好的线性关系，相关系数r=0.9996(n=5）。本法具简单、快速、易操作等优点，结果满意。     

电喷雾串联质谱法检测氯霉素的初步研究

研究了串联质谱MS／MS分析氯霉素的方法，以国外资料所提供的参数为基础，经过优化和补充建立了一套完整、检测灵敏度更高的质谱仪参数：锥孔电压30V，碰撞电压分别为m／z152，20eV,m/z194,10eV,m/z257,9eV。     

实验室污染对氯霉素残留检测的影响

分析实验室氯霉素污染来源及其对氯霉素残留检测的影响.以乙腈为溶剂,对实验台面、实验器具表面的污染物进行收集,应用液相色谱-质谱法(HPLC-MS/MS),对收集液中的氯霉素含量进行测定;以浸泡过氯霉素的实验器具为阳性对照,考察实验器具的清洗方法对氯霉素去除效果.结果表明:大部分实验器具的污染物提取液检出了氯霉素,阳性实验器具清洗后仍检出氯霉素.实验室污染可能造成实验结果假阳性,因此,建立有效的预防体系避免实验室污染,对减少痕量分析中假阳性的出现具有重要意义.     

生猪氯霉素残留检测分析

为了解本市猪肉中兽药残留情况,随机抽查凌海市几个周边县区农贸市场市售鲜猪肉,检测氯霉素的残留情况。采用酶联免疫吸附法（ELISA）,取猪肝160份测定氯霉素残留,结果阳性数10份,检测阳性率6．25％。检测结果不容乐观。为确保本市鲜猪肉供应的食品安全,应加强源头监控。     

氯霉素类抗生素药物对人类健康的威胁

氯霉素类抗生素对多种革兰氏阳性和革兰氏阴性致病菌引起的疾病具有较好的治疗作用,是一种常见的广谱抗菌药,在动物医学领域使用非常频繁.但是氯霉素类抗生素普遍残留于食源性动物体内,严重影响食品安全,给人类健康带来较大威胁.文章对氯霉素及其二代、三代产品的相关问题进行了分析比较,为食源性动物养殖者和广大消费者提供参考.     

虾肉中氯霉素甲砜霉素氟苯尼考及氟苯尼考胺残留气相色谱-微电子捕获检测法

氯霉素类药物是一类广谱抗生素，主要包括氯霉素（CAP）、甲砜霉素（TAP）和氟苯尼考（FF），兽医临床上用于治疗畜禽的细菌性疾病。但由于氯霉素具有抑制造血功能及引起再生障碍性贫血等毒性作用，因此许多国家都禁止将其应用于食品动物。甲砜霉素的毒性较氯霉素低，但其抗菌效能不及氯霉素。而氟苯尼考作为新型氯霉素类抗生素，在安全性和有效性方面比氯霉素和甲砜霉素具有明显的优势，已在养殖业中大规模使用，但由于兽医临床的滥用、误用，细菌耐药性问题越来越严重，因此我国、欧盟及美国均规定了动物组织中氟苯尼考的最大残留限量。     

氟苯尼考等兽药对莱克多巴胺ELISA检测的影响

本文通过对氟苯尼考等常用兽药对莱克多巴胺ELISA残留筛选检测的影响研究实验。结果表明,这些药物在5ng/ml(或10ng/ml)作为我国动植物检验检疫判定标准下,对莱克多巴胺ELISA检测无影响。     

禽肉中氯霉素药残的快速检测

近年来 ,在对外出口畜禽食用产品时 ,对氯霉素残留的检测成为必不可少的检测指标。国外一般要求畜禽食用产品中氯霉素不得超过 1ｎｇ/ｍｌ,这对检测手段的灵敏度提出了很高的要求。目前我国国内常用的检测氯霉素药残的方法是使用液相法或气相色谱法来对其进行检测 ,但这种检测方法对样品的处理比较复杂 ,对实验操作技术要求很高 ,不利于在基层生产单位推广应用。本实验根据酶联免疫吸附 (ＥＬＩＳＡ)借助于氯霉素残留快速检测试剂盒对鸡肉组织残留的氯霉素进行检测 ,处理简单 ,操作步骤简便 ,可以快速有效地测定出肉品中的氯霉素残留量 ,其…     

Antibacterial effect of chloramphenicol, thiamphenicol and florfenicol against aquatic animal bacteria

The minimum inhibitory concentration (MIC) was measured to evaluate the antibacterial activities of chloramphenicol (CP), thiamphenicol (TP) and florfenicol (FFC) against the aquatic bacterial isolates from soft-shell turtles, fish and shellfish. Amoxicillin (AMPC), oxytetracycline (OTC) and oxolinic acid (OA) were included to compare with above protein synthesis inhibitors. The results showed that the order of MIC range of the isolates from soft-shell turtles for tested drugs was OA>FFC, CP>TP> AMPC, OTC. The percentage of the resistant strains indicated that OA was the lowest (7.14%) and OTC was the highest (85.07%). The order of antibacterial activity against the isolates from fish was OA>FFC>CP>AMPC>OTC>TP. The percentage of the resistant strains revealed that OA (13.64%) and OTC (80.91%) were the lowest and the highest, respectively. For the isolates from shellfish, the order of antimicrobial activity was OA>CP, FFC>AMPC, OTC, TP. TP showed the greatest percentage of the resistant strains (58.7%), but that of OA was the lowest (4.35%). The most common resistant patterns of the isolates from turtles, fish and shellfish were AMPC-OTC, CP-TP-AMPC-OTC, and FFC-CP-TP-AMPC-OTC, respectively. There were partially-complete resistance of the resistant isolates among CP, TP and FFC. The findings indicated that previous treatment might affect the choice of drug to use for aquatic bacterial diseases.     

高效液相法测定复方氟苯尼考注射液中氟苯尼考的含量

建立了测定氟苯尼考注射液中氟苯尼考含量的高效液相色谱法。采用C18色谱柱（4.6 mm×150 mm,5μm）,流动相为甲醇∶水（pH值为3.0）为40∶60（v/v）,流速为1 mL/min,检测波长为222 nm,进样10μL,柱温为室温。氟苯尼考浓度在0.1-3 mg/mL范围内,峰面积与浓度的线性关系良好（R^2=0.999 6）;平均回收率为99.49%,RSD为1.12%（n=4）。此法简便、快速、灵敏度高、重现性好。     

In vitro assessment of chloramphenicol and florfenicol as second‐line antimicrobial agents in dogs

The aim of this study was to evaluate the potential of chloramphenicol and florfenicol as second‐line antimicrobial agents for treatment of infections caused by methicillin‐resistant Staphyococcus pseudintermedius (MRSP) and extended‐spectrum β‐lactamase (ESBL)‐producing Escherichia coli in dogs, through a systematic in vitro assessment of the pharmacodynamic properties of the two drugs. Minimum inhibitory concentrations (MIC) and phenicol resistance genes were determined for 169 S. pseudintermedius and 167 E. coli isolates. Minimum bactericidal concentrations (MBC), time‐killing kinetics, and postantibiotic effect (PAE) of both agents against wild‐type isolates of each species were assessed. For S. pseudintermedius, the chloramphenicol MIC₉₀ was 32 μg/mL. No florfenicol resistance was detected in this species (MIC_90 = 4 μg/mL). The MIC₉₀ of both agents against E. coli was 8 μg/mL. Resistance genes found were cat_pC221 in S. pseudintermedius and catA1 and/or floR in E. coli. The phenicols displayed a time‐dependent, mainly, bacteriostatic effect on both species. Prolonged PAEs were observed for S. pseudintermedius, and no PAEs were detected for E. coli. More research into determination of PK/PD targets of efficacy is needed to further assess the clinical use of chloramphenicol and florfenicol as second‐line agents in dogs, optimize dosage regimens, and set up species‐specific clinical break points.     

氟苯尼考纳米晶在鸡体内的药动学

氟苯尼考(florfenicol, FFC)是新型动物广谱抗菌剂,抗菌效果好,广泛应用于牛、羊、猪、水产及禽类等动物细菌性疾病的防制。本试验旨在研究FFC和氟苯尼考纳米晶(florfenicol nanocrystal, FFC-NC)在鸡体内的生物利用度。采用交叉试验法,鸡用药后,在不同时间点翅下静脉采血,利用高效液相色谱法(high performance liquid chromatography, HPLC)测定血浆中FFC含量。结果显示,此试验所建立的HPLC色谱图基线平稳,血浆峰与FFC峰完全分离。回收率和精密度均符合测定要求,重复性好,适用于鸡血浆FFC含量测定。药动学参数结果显示,与FFC组相比,FFC-NC组的达峰时间t_max为(0.875±0.137) h,峰时缩短,药时曲线下面积AUC₍(0-∞))和峰浓度C_max分别为(23.957±2.338) mg/(L·h)和(8.249±0.713) mg/L,FFC-NC组的相对生物利用度是FFC组的3.6倍。结果表明,FFC-NC的药动学特征较FFC均...     

氟苯尼考(florfenicol)在水产养殖中的应用

饲料级抗生素氟苯尼考(FFC)已经在水产养殖中广泛应用于防治细菌性疾病,在日本的黄狮鱼、真鲷、虹鳟、银鲑、竹荚鱼,韩国的黄狮鱼、鳗鱼和英国的大西洋鳟上已批准使用。氟苯尼考是专用于水产饲料的抗生素药之一,目前在其它养殖品种中的应用研究还在继续。氟苯尼考由总部设在美国的先灵葆雅公司开发,本药品在美国已被批准用于肉牛和猪,商标是AquaflorR。去年,位于密西西比州立大学兽药学院的国家温水鱼类养殖中心对FFC在斑点叉尾鮰上的功效做了相关试验,以鉴定其抗爱德华氏病(Edwardsiellaictaluri,一种在斑点叉尾鮰身上引起肠炎性败血症…     

反溶剂沉淀法制备氟苯尼考纳米结晶

为了制备并固化氟苯尼考纳米结晶(FF-NC),采用反溶剂沉淀法制备FF-NC,正交试验筛选最优处方,固化并考察其冻干粉的体外溶出度。结果:在处方和工艺筛选的基础上,确定最优处方。选择羟内甲纤维素(HPMC)及泊洛沙姆188(F68)为稳定剂和助稳定剂,稳定剂∶助稳定剂=5∶1,良溶剂∶不良溶剂=1∶9,药物浓度为4 mg/mL,稳定剂浓度为5 mg/mL,滴加速度为5 mL/min。制得FF-NC平均粒径为(157.7±6.3) nm,多分散系数(PDI)为0.219±0.042,以1%PVP为冻干保护剂制得的冻干粉性质最佳,外观细腻光滑,复溶效果好,冻干前后粒度没有显著差异,冻干粉体外累积溶出度显著高于原药。反溶剂沉淀法制备FF-NC工艺简便,值得进一步研究。     

Laboratory efficacy of florfenicol against Streptococcus iniae infection in sunshine bass

An experimental feeding trial was performed to evaluate the efficacy of florfenicol (FFC) in controlling Streptococcus iniae infection in sunshine bass (female white bass Morone chrysops x male striped bass M. saxatilis). Five dosage levels of FFC in medicated feed were administered daily: 0, 5, 10, 15, and 30 mg of active ingredient/kg of fish body weight. Treatment was started within 22-24 h postchallenge by waterborne exposure to virulent S. iniae. The FFC medication was continued for 10 consecutive days, followed by a 25-d posttreatment observation. At the conclusion of the experiment, FFC treatment significantly increased the survival of S. iniae-challenged sunshine bass from 4.2% in the nonmedicated (positive control) group to 69.2% in the 5-mg/kg dosage group, 86.7% in the 10-mg/kg group, and 94.2% in the 15- and 30-mg/kg groups. Survival was significantly higher in the 15- and 30-mg/kg treatment groups than in the 5-mg/kg treatment group; differences among the 10-mg/kg and higher dosage groups were not significant. Survival curve analysis using a log-rank test indicated no significant difference between curves for the 10- and 15-mg/kg groups but a significant difference between curves for the 5- and 10-mg/kg groups. At the end of the experiment, no carriers were detected in any challenged group receiving an FFC-medicated diet, but the bacterium was recovered from the nonmedicated challenged survivors of the infection. The results of the experiment suggest that the optimum therapeutic daily dose of FFC is between 10 and 15 mg/kg body weight for 10 d.