水库暴发性鱼病及其防治技术研究Ⅲ某些药物对鲢暴发病病原菌的试管内抗菌作用

报道了１２种药物在试管内对８株从患病白鲢上分离的嗜水气单胞菌的最小抑制浓度和最小杀菌浓度。被检测的８株致病菌对青霉素、氯霉素、甲哌利福霉素、土霉素有高度感受性，其最小抑菌浓度为０．０２５－１．５６μｇ／ｍｌ，最小杀菌浓度为０．０２５－３．１３μｇ／ｍｌ，最小抑菌和杀菌浓度比率为１－２。对红霉素、异烟肼、胜利霉素和呋喃唑酮的感受性较低，最小抑菌浓度为３．１３－２５μｇ／ｍｌ，最小杀菌浓度为６．２５－１００μｇ／ｍｌ，最小抑菌和杀菌浓度的比率为２－３。对磺胺胍、磺胺嘧啶、大蒜素和鱼健灵的感受性最低，最小抑菌浓度２５－＞１００μｇ／ｍｌ，最小杀菌浓度５０－＞１００μｇ／ｍｌ，其最小抑菌和杀菌浓度比率为１－＞２。     

水库暴发性鱼病及其防治技术研究：Ⅲ某些药物对鲢暴发病病原菌的试管…

报道了１２例药物在试管内对８株从患病白链上分离的嗜水气单胞菌的最小抑制浓度和最小杀菌浓度。被检测的８株致病菌对青霉素、氯霉素、甲哌利福霉素、土霉素有高度感受性，其最小抑菌浓度为０．０２５－１．５６μｇ／ｍｌ，最小杀菌浓度为０．０２５－３．１３μｇ／ｍｌ，最小抑菌和杀菌浓度比率为１－２。对红霉素、异烟肼、胜利霉素和呋喃唑酮的感受性较低，最小抑菌浓度为３．１３－２５μｇ／ｍｌ，最小杀菌浓度为６．２５－     

嗜水气单胞菌对几种抗生素耐药性的形成及消失速率

3株嗜水气单胞菌经药物浓度递增继代培养10代后，对土霉素的最小抑菌浓度（MIC）由0．10μg／ml上升到0．39μg／ml，上升4倍；氟霉素的MIC由0．05μg／ml上升到0．39μg／ml，上升8倍；链霉素的MIC由0．05μg／ml上升到0．10μg／ml，上升2倍；红霉素的MIC由0．20μg／ml上升到1．56μg／ml，上升8倍。而将已获得耐药性的菌株经元添加药物继代培养10代后，上霉素和氯霉素的MIC降到0．10μg／ml，链霉素的MIC降到0．05μg／ml，红霉素的MIC降到了0．39μg／ml。     

嗜水气单胞菌对4种中草药和4种抗生素耐药性的比较研究

ＳＨ－９２－０２和Ｃ－９５０５０１两菌株对大黄,穿心莲,诃子,连翘、呋喃唑 酮,氟哌酸,氯霉素和土霉素的ＭＩＣ分别为１６ｍｇ／ｍＬ、２５０ｍｇ／ｍＬ、０．１２ｍｇ／ｍＬ、３．９ｍｇ／ｍＬ、０．１２μｇ／ｍＬ、０．０３４μｇ／ｍＬ、０．３１μｇ／ｍＬ、０．９７μｇ／ｍＬ和３０、５００、０．１２、３．９、０．９７、０．１２、０．９７、１．９５ｍｇ／ｍＬ。１０次药物肖工递增继代培养,共试菌株ＳＨ－９２－     

氟苯尼考对六种海洋致病弧菌的体外抗菌活性研究

测定了氟苯尼考等4种抗菌药对6种常见海洋致病弧菌的最小抑菌浓度(MIC)和最小杀菌浓度(MBC)。测试结果显示，氟苯尼考对6株弧菌的MIC值范围为2～4μg／mL，氯霉素为1～32μg／mL，土霉素为4～128μg／mL，恩诺沙星为0．125～1μg／mL；对多数弧菌氟苯尼考与氯霉素的抗菌活性相似。氟苯尼考对6株弧菌的MBC／MIC值范围为2-4，而氯霉素为2～16，表明氟苯尼考的杀菌效果优于氯霉素。对照药物恩诺沙星、土霉素的MBC／MIC值分别为1-2和2-8，恩诺沙星显示出优良的抗菌和杀菌活性。随着接种菌量增加，所测3种抗菌药的MIC随之升高；当接种量达到10^7ufu／mL时．药物对多数弧菌显示出微弱的作用。     

罗氏沼虾育苗期抑菌药物试验

在罗氏沼虾工厂化育苗期间，用２ｍｇ／Ｌ浓度的高锰酸钾溶液浸浴幼体，可以在短时间内有效抑菌，用１ｍｇ／ｍｌ的土霉素溶液浸浴幼体，能有效抑菌。通过酸试验，高锰酸钾和土霉素的抑菌效果与ＰＨ的降低相关性不强。     

10种甲鱼致病菌对二氧化氯的敏感性测定

测定了二氧化氯对１０种甲鱼致病菌在营养肉汤中的最小抑菌浓度（ＭＩＣ）和在池塘水中的最小杀菌浓度（ＭＢＣ）。结果表明：二氧化氯在肉汤中对病原菌有一定抑菌效果，对其中６种菌的ＭＩＣ小于２５μｇ／ｍｌ；二氧化氯在池塘水中的杀菌效果较理想，对其中７种致病菌的ＭＢＣ小于６．２５μｇ／ｍｌ；以作用３０ｍｉｎ杀菌效果最佳。二氧化氯用于甲鱼病害防治是一种较有前途的药物。     

10种于致病菌对二氧化氯的敏感性测定

测定了二氧化氯对１０种甲鱼致病攻在营养肉汤中最小抑菌浓度（ＭＩＣ）和在池塘水中的最小杀菌浓度（ＭＢＣ）。结果表明：二氧化氯在肉汤中对病原菌有一定抑菌效果，对其中６种菌的ＭＩＣ小于２５μｇ／ｍｌ；二氧化氯在池塘水中的杀菌效果较理想，对其中７种致病菌的ＭＢＣ小于６．２５μｇ／ｍｌ；以作用３０ｍｉｎ杀菌效果最佳。二氧化氯用于甲鱼病害防治是一种较有前途的药物。     

嗜水气单胞菌欧洲鳗皮肤溃疡分离株的耐药性

1996年6～8月自福建省霞浦县某养鳗场患狂游症的欧洲鳗(AnguillaanguillaL.)下颏溃疡处分离到15株细菌,经鉴定为嗜水气单胞菌(Aeromonashydrophila)。用药敏纸片法对其进行常用抗菌药物敏感试验,结果表明耐药菌株率分别为:痢特灵,73.3%;复方新诺明(SMZ TMP),73.3%;四环素,86.7%;土霉素,53.3%;红霉素,53.3%;氯霉素,73.3%;氟哌酸(诺氟沙星),60.0%;环丙沙星,60.0%。测定其最小抑菌浓度(MIC)平均值分别为:痢特灵,28.0μg/ml;复方新诺明1424.0μg/ml;四环素,112.0μg/ml;土霉素,992.0μg/ml;红霉素,103.5μg/ml;氯霉素,136.3μg/ml;氟哌酸,98.0μg/ml和环丙沙星,45.0μg/ml,均远远高于药物使用浓度。被测菌株一般对4种以上抗菌药物耐药,个别菌株对全部测试药物耐药。说明在养殖过程中频繁使用抗菌素,已产生了广泛的耐药菌株。     

鱼用新药“康达富”对鳗鲡弧菌和福建爱德华氏菌的杀灭作用

用２倍稀释法测定了新药“康达富”对鳗鲡弧菌、鳗鲡福建爱德华氏菌的杀灭作用，结果表明，该药对鳗鲡弧菌、鳗鲡福建爱德华氏菌有极强的杀灭作用，其最低抑菌浓度分别为０．００４ｍｇ／ｍｌ和０．０００４ｍｇ／ｍｌ，最低杀菌浓度分别为０．００８ｍｇ／ｍｌ和０．０００８ｍｇ／ｍｌ。采用琼脂扩散纸片法，检测了“康达富”商品药的原药Ａ和原药Ｂ对鳗鲡福建爱德华氏菌的联合杀灭作用，结果表明，两种原药的杀灭效果呈显著的累加作用。     

Pharmacodynamics of amoxicillin against field isolates of Streptococcus parauberis from olive flounder (Paralichthys olivaceus)

Olive flounder is the most important species for the Northeast Asian fish farming industry. However, this species is substantially affected by multiple infectious agents, including Streptococcus parauberis. Evaluation of antibiotics before their application is critical to treat infections and prevent drug resistance. Therefore, in this study, the pharmacodynamics of amoxicillin (AMX) and other antimicrobials against the planktonic‐ and biofilm‐forming bacteria were assessed. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and Time–kill curve assay were analysed using micro‐dilution method. The minimum biofilm eradicating concentration (MBEC) was determined using the Calgary Biofilm device. The effects of temperature, pH, hardness and salinity were detected for both planktonic‐ and biofilm‐forming bacteria. The MIC of AMX ranged from 0.015 to 2 μg/ml, whereas that of cephalexin (CEP), enrofloxacin (ENR) and oxytetracycline (OTC) ranged from 0.125 to 256, 0.125 to >512 and 0.25 to >512 μg/ml respectively. No bacteria were resistant against AMX, while the percentage of resistance to CEP, OTC and ENR were 68.7%, 52.6% and 11.1% respectively. The IC₅₀ of AMX, CEP, ENR and OTC was 0.03, 0.091, 0.015 and 0.213 μg/ml respectively. The MBEC of amoxicillin against S. parauberis ranged from 0.5 to 16 μg/ml. Higher rates of bacterial growth were obtained at 30°C, pH = 8 and salinity of 7.5–10 ppt. The hardness of the media suppressed the bacterial growth. In conclusion, AMX was found to be effective against both the planktonic and the biofilm forms of the prominent fish pathogen, S. parauberis.     

土霉素在红鳍东方鲀体内的残留及休药期研究

在14±2℃水温条件下，连续5d对红鳍东方鲍口灌剂量为100mg／kg的土霉素，采用高效液相色谱法测定了停药后血清、肌肉、肝脏组织中的药物含量、消除速率常数和消除半衰期，提出了该温度下的休药期。研究表明，在停药2d后红鳍东方鲍血清和肌肉中的药物浓度达到峰值，分别为1．092μg／ml和0．806μg／g；停药3d后肝脏内土霉素浓度达到峰值1．229μg／g，土霉素在血清、肌肉和肝脏中的消除半衰期分别为23．8、22．4和26．8d；土霉素在红鳍东方纯肌肉组织中降到0．1μg／g残留限量的时间为58d，降到0．05μg／g残留限量的时间为81d。     

高度耐药嗜水气单胞菌的定向诱导及其交叉耐药性分析

为了分析比较不同抗生素对耐药嗜水气单胞菌(Aeromonas hydrophila)的诱导效率,从五大类抗生素中各挑选出一种代表性的抗生素,在针对嗜水气单胞菌菌株AH10的防耐药突变浓度(mutant prevention concentration,MPC)的琼脂平板上,分别筛选出五株耐药菌株,并对筛选的耐药菌株进行交叉耐药性分析,制定出这些耐药菌株对常用抗生素的最小抑菌浓度(minimal inhibitory concentrations,MIC)图谱。结果显示:四环素、氟苯尼考、磺胺嘧啶、硫酸新霉素、诺氟沙星对AH10的MIC分别为:1.0、0.5、8.0、8.0、0.25μg/m L;MPC分别为4.0、3.0、128、88、2.0μg/m L,分离的耐药菌株对所使用抗生素的MIC均提高100倍以上。4℃划线平板冰箱保存条件下,一个月内个别耐药菌株耐药性下降。在药物筛选压力下,菌株耐药性随着传代次数增多而表现出递增的趋势。同属一类抗生素耐药相关性较高;不同大类抗生素压力下筛选出来的耐药菌株表现出不同的交叉耐药性。     

Oxytetracycline (OTC) uptake following bath treatment in gilthead sea bream (Sparus aurata)

The uptake and elimination profile of oxytetracycline (OTC) following a prolong bath treatment in gilthhead sea bream (Sparus aurata) were investigated in this study. The bath experiment was carried out using a OTC concentration of 50 μg/ml for 24 h at 17-18 °C water temperature. Plasma and muscle fish samples were analysed at 1, 3, 6 and 24 h during and at 1, 2, 3, 4 and 6 d following the bath. Detectable OTC levels were revealed only at the end of bath treatment (24 h) in examined tissues of gilthead sea bream, where drug concentration was measured to be as low as 0.096 and 0.047 μg/g or ml in muscle plus skin and plasma, respectively. The findings of the present study indicate that OTC bath treatment under this dosage schedule is unlikely to confront systemic bacterial infections.     

土霉素在黑鲷体内的药物代谢动力学研究

首次报道了黑鲷口服土霉素的药物代谢动力学特征，用高效液相色谱法测定组织中的药物含量，药物在肌肉，血液，肝脏中的平均回归率分别为８５.61%,85.38%,82.005,该方法的检测限可达0.01μg/g，黑鲷１次口服剂量为７５mg/kg的土壤素后，其血液药物浓度－时间数据符合一室开放动力学模型，吸收速率常数（ka)为０.296/h，达峰时间（Ｔamx)为１０.635h,峰浓度（Ｃmax)为１.398μg/ml, 分布半衰期（Ｔ１／２a）为２.339h ,消除半衰期(T1/20β）为46.663h，药时曲线下面积（ＡＵＣ）为１１0.25mg/L.h，黑绸口服药物０.5h后在血液，肥肉，肝脏，肾脏４种组织中就可以检测到药物的存在，药物在１６h的采样点浓度达最高，分别为1.68μg/ml,1.68,2.52,6.77μg/g。     

Pharmacokinetics and bioavailability of oxytetracycline in vannamei shrimp (Penaeus vannamei) and the effect of processing on the residues in muscle and shell

The present study examined the pharmacokinetics and bioavailability of oxytetracycline (OTC) in vannamei shrimp (Penaeus vannamei) after intra-sinus (10 mg/kg) and oral (10 and 50 mg/kg) administration and also investigated the net changes of OTC residues in the shrimp after the thermal, acid and alkaline processing methods. The hemolymph concentrations of OTC after intra-sinus dosing were best described by a two-compartment open model. The oral bioavailability was found to be 48.2 and 43.6% at doses of 10 and 50 mg OTC/kg, respectively. The peak hemolymph concentrations after 10 and 50 mg OTC/kg doses were 3.37 and 17.4 μg/ml; the times to peak hemolymph concentrations were 7 and 10 h. The elimination half-lives were found to be 15.0 and 11.5 h for the low and high dose, respectively. The residual OTC was rapidly eliminated from muscle with the elimination half-life value of 19.4 and 15.4 h, respectively, for the groups treated with doses of 10 and 50 mg/kg. The residual OTC levels in the muscle fell below the MRL (0.2 μg/g) at 72 and 96-h post-dosing at dose levels of 10 or 50 mg/kg, respectively. Residual OTC levels in muscle and shell were approximately 20–50% lower in the thermal treatment such as boiling, baking and frying. By the acid treatment, OTC residues were reduced to >80%, while those were reduced to around 30% by alkaline treatment.     

半咸水_海水对几种渔用抗菌药物体外活性的影响

研究了人工海水、天然半咸水以及生理盐水对６种我国常用抗菌药物（环丙沙星、四环素、土霉素、氯霉素、磺胺以及呋喃唑酮）体外抗两种鱼类病原细菌（Ａｅｒｏｍｏｎａｓ ｈｙｄｒｏｐｈｉｌａ和Ｖｉｂｒｉｏ ｆｌｕｖｉａｌｉｓ）活性的影响。结果表示：海水对几乎所有受试药物的抗菌活性均呈抑制作用,其中对土霉素的影响最为显著;半咸水可使土霉素、四环素及磺胺药的抗菌活性下降;生理盐水对不同药物或不同细菌的作用不一致;     

Bath efficacy of sodium hypochlorite,oxytetracycline dihydrate and chloramphenicol against bacterial black disease in fairy shrimp Branchinella thailandensis

To control black disease infecting fairy shrimp Branchinella thailandensis, the effects of concentrations and exposure time to three effective antimicrobials, which inhibited the pathogens in vitro, were evaluated. Exposure to sodium hypochlorite (NaOCl) caused a great toxicological response in the shrimp, 100% mortality was observed within 30 min–2 h at 5–20 μg mL^?1. For oxytetracycline dihydrate (OTC) and chloramphenicol (CP), short‐term exposure to four high concentrations up to 5 h and long‐term exposure (12 days) to four low concentrations were used to determine an appropriate method for bath efficacy. Long‐term exposure to low concentrations was more toxic than the short‐term. Short‐term exposure to OTC showed the highest survival rate and CP was considered more toxic. The minimum survival rate of the shrimp exposed to both antibiotics at 250 μg mL^?1 for 3 h was 83.3%. For determination of the bath efficacy, a short–term exposure (3 h) to OTC and CP was conducted using artificially infected shrimp. Administration of OTC and CP at 250 and 500 μg mL^?1 resulted in the highest survival rates of 56.7% and 46.7% respectively. This study demonstrated that bath administration with OTC could be an alternative method for the treatment of black disease in fairy shrimp cultivation.     

Delivery of Bioencapsulated Oxytetracycline to the Marine Shrimp Penaeus monodon

Abstract Post larvae of shrimp Penaeus monodon were fed Artemia sp. enriched with oxytetracycline (OTC). The amounts of this antibiotic in the Artemia sp., the shrimp, and the water of the experimental system were measured by radial diffusion bioassay. The results indicated that 11% of the OTC was taken up by the Artemia sp. After 8 d of being fed OTC-enriched Artemia sp., the shrimp were found to contain 3.12 μg OTC/shrimp, which is twelve times greater than the average minimum inhibitory concentration (MIC) cited in the literature for sensitive strains of Vibrio spp. The recommended therapeutic dose for treatment of bacterial infections is four times the MIC.     

恶喹酸与诺氟沙星对异育银鲫体内嗜水气单胞菌的抑菌效果比较

在水温(25±2)℃下,给体质量150~200g的异育银鲫分别口灌3种剂量(20、30、40mg/kg)的诺氟沙星和恶喹酸,结合这两种药物对嗜水气单胞菌AH10的体外药效学研究和对异育银鲫单次口灌不同剂量的诺氟沙星、恶喹酸的体内药代动力学,研究诺氟沙星、恶喹酸对异育银鲫体内嗜水气单胞菌AH10的抑菌效果。试验结果表明,恶喹酸和诺氟沙星对嗜水气单胞菌AH10的最小抑菌质量浓度分别为1μg/mL和0.5μg/mL。口灌上述3种剂量恶喹酸、诺氟沙星后,异育银鲫血浆中恶喹酸的最大药物质量浓度分别为4.1μg/mL、6.0μg/mL和8.89μg/mL;诺氟沙星的最大药物质量浓度分别为11.5μg/mL、15.1μg/mL和18.9μg/mL;恶喹酸的最大药物质量浓度/最小抑菌质量浓度分别为4.1、6.0和8.89;诺氟沙星的最大药物质量浓度/最小抑菌质量浓度分别为23、30.2和37.8;恶喹酸0~24h内药—时曲线下面积/最小抑菌质量浓度分别为21.6214、33.1449、39.1846;诺氟沙星0~24h内药—时曲线下面积/最小抑菌质量浓度分别为274.75、451.55、578.35。综合0~24h内药—时曲线下面积/最小抑菌质量浓度、最大药物质量浓度/最小抑菌质量浓度这两个指标可知,诺氟沙星对异育银鲫体内的嗜水气单胞菌AH10抑制效果强于恶喹酸。