试验性抗菌药对仔猪水肿病治疗效果

保定市某猪场暴发疫病，经病理剖检、病原分离、生化试验、毒力试验等诊断方法获知此次疫情为致病性埃希氏大肠杆菌引起的猪水肿病。药敏实验表明．细菌分离物对青霉素、链霉素等常用抗生素有耐药性，对氟苯尼考、卡那霉素、环丙沙星等药物极敏。感染猪选用氟苯尼考治疗后康复。     

猪链球菌的分离鉴定与药物治疗

猪链球菌病是猪的一种常见传染病。由于链球菌有多个血清型,给临床防治带来一定困难。为了临床上能够有效控制和治疗猪链球菌病,本人对猪链球菌病进行了病原分离及药物试验。结果,猪链球菌分离株对先锋九号、氟苯尼考、先锋五号3种抗生素敏感,对卡那霉素、复方新霉素、环丙沙星、链霉素4种抗生素耐药。采取饲养环境和栏舍带猪消毒,饲料添加敏感药物,发病猪隔离和治疗等措施,可有效控制本病发生。     

猪链球菌的分离鉴定与药物治疗

猪链球菌病是猪的一种常见传染病。由于链球菌有多个血清型，给临床防治带来一定困难。为了临床上能够有效控制和治疗猪链球菌病．本人对猪链球菌病进行了病原分离及药物试验。结果，猪链球菌分离株对先锋九号、氟苯尼考、先锋五号3种抗生素敏感，对卡那霉素、复方新霉素、环丙沙星、链霉素4种抗生素耐药。采取饲养环境和栏舍带猪消毒，饲料添加敏感药物，发病猪隔离和治疗等措施，可有效控制本病发生。     

氟苯尼考酯(钠)对禽致病性大肠杆菌的治疗对比试验

试验主要探讨氟苯尼考酯(钠)与10%水溶性氟苯尼考对禽致病性大肠杆菌的治疗对比试验。试验采用动物回归治疗试验和小白鼠致病治疗对比试验,比较其在治疗效果等多方面的差异性。结果显示:氟苯尼考酯(钠)对禽致病性大肠杆菌感染的治愈率明显优于10%水溶性氟苯尼考,差异显著(P<0.05);有效率优于10%水溶性氟苯尼考,但差异不显著(P>0.05);其治疗成本低于30%水溶性氟苯尼考。     

金鱼竖鳞病病原菌的分离鉴定及药敏试验

为进一步了解引起金鱼竖鳞病的原因和病原,从患竖鳞病的濒死金鱼体内分离出3株细菌,经细菌形态、培养特征、生理生化特性鉴定,3株细菌均为嗜水气单胞菌。感染试验证实,分离菌具有较强的致病性。药敏试验结果显示,该菌对氟苯尼考、菌必治、左氧氟沙星、氯霉素、新霉素、恩诺沙星等药物高度敏感。     

鸡致病性大肠杆菌分离鉴定及药敏试验

以干海乡一生态鸡鸡苗场中分离得到的鸡致病性大肠杆菌病原菌为试验对象,采用细菌形态学观察以及生化试验、动物试验和血清学试验等方法,表明所分离到的5个菌株为致病性大肠杆菌。用氨苄青霉素、庆大霉素、四环素、磷霉素、新霉素、土霉素、链霉素、红霉素、氟苯尼考、氧氟沙星、头孢曲松、阿莫西林等12种药物对5个不同菌株进行药敏试验比较。结果表明:5个菌株均对新霉素、阿莫西林、头孢曲松和磷霉素高度敏感。对庆大霉素、四环素、土霉素等抗菌药物耐药性极强。     

中华鳖源粘质沙雷氏菌分离、鉴定及药敏特性研究

对患病中华鳖(Trionyn sinensis)进行病原分离、鉴定及药敏实验。从患病中华鳖肝、肾、脾及腹水分离纯化病原菌,经理化特性测定及16S rRNA序列分析对其进行鉴定,开展人工感染试验,并利用K-B进行药敏特性分析。结果显示分离菌株HD01为本次引发中华鳖病害的病原菌,其对中华鳖的LD50为4.48×106CFU/g。HD01株理化特性与粘质沙雷氏菌一致,16S rRNA序列与粘质沙雷氏菌同源性为99%,综合判定分离菌株为粘质沙雷氏菌(Serratia marcescens)。HD01株对氟苯尼考、多西环素、庆大霉素及苯唑西林等14种抗生素高度敏感;对青霉素、头孢拉定、新霉素等7种抗生素耐药。分离菌株HD01是中华鳖病原菌,养殖时可选用氟苯尼考、庆大霉素及多西环素等药物进行防控。     

氟莱西注射液对猪传染性胸膜肺炎有较好疗效

广西北斗星动物保健品有限公司吴健华等，以自然患传染性胸膜肺炎的病猪为实验对象，观察氟莱西注射液与氟苯尼考注射液、盐酸多西环素注射液的疗效对比试验．结果：氟莱西注射液试验组的高、中、低剂量组治疗猪传染性胸膜肺炎的总有效率分别为93．3％、90．0％、73．3％，氟苯尼考注射液的总有效率为86．7％；     

氟苯尼考琥珀酸钠对鸡慢性呼吸道病的治疗试验

试验选取氟苯尼考琥珀酸钠、水溶性氟苯尼考、酒石酸泰乐菌素、盐酸左旋氧氟沙星和阿齐霉素6种抗菌药物,对自然感染鸡败血霉形体的病鸡进行治疗试验,以评价6种抗菌药物对自然感染鸡败血霉形体病鸡的治疗效果。试验结果表明:氟苯尼考琥珀酸钠和阿齐霉素对鸡败血霉形体病具有较好的治疗效果,治愈率分别为96%和93%,有效率分别为98%和96%。氟苯尼考琥珀酸钠和阿齐霉素治愈率和有效率明显优于水溶性氟苯尼考、盐酸左旋氧氟沙星和酒石酸泰乐菌素(P<0.05),氟苯尼考琥珀酸钠治愈率和有效率优于阿齐霉素,但差异不显著(P>0.05)。     

一株梭鲈源无乳链球菌的分离、鉴定及分子分型分析

为查明梭鲈(Lucioperca lucioperca)凸眼病病原,从患病梭鲈病灶眼、肝、脾和肾分离纯化病原菌,进行了生理生化特性测定及16S rRNA基因序列分析,并开展人工感染试验,测定其血清型及MLST分型,并利用纸片扩散法进行药敏特性分析。结果显示:分离菌株(命名为SL1701株)为本次引发梭鲈病害的致病菌,Ib-ST261型。回归感染实验证实,分离得到的细菌SL1701对健康梭鲈具有非常强的致病性,4.5×105CFU/m L时可使80%受感染梭鲈死亡,并可复制出自然发病鱼的症状。菌株SL1701革兰氏染色为阳性链球菌,γ溶血,生理生化特性与普通无乳链球菌基本一致,16S rRNA基因序列与无乳链球菌(Streptococcus agalactiae)同源性最高,综合判定分离菌株为无乳链球菌(Streptococcus agalactiae)。药敏试验结果显示:分离菌株SL1701对氟苯尼考、氟罗沙星等17种抗生素高度敏感,对青霉素、磷霉素等8种抗生素耐药。结果表明,分离菌株SL1701为Ib-ST261型无乳链球菌,养殖时可选用氟苯尼考及氟罗沙星等药物进行防控。     

南美白对虾病原性豚鼠气单胞菌的分离与药敏特性

为查明引起上海青浦地区养殖南美白对虾黄腿病的病原菌,提供养殖户防控该病的有效药物,采用传统方法从患黄腿病的南美白对虾肝胰腺组织中进行了病原菌的分离,通过人工回归感染试验确定了病原菌株,采用API ID32GN生理生化鉴定和16S rRNA序列分析对病原菌株进行鉴定,通过纸片扩散法分析病原菌株的药敏特性。结果表明,从病虾的肝胰腺中分离到一株病原菌(QPX1),经生理生化特性与16S rRNA序列分析确定其为豚鼠气单胞菌(Aeromonas caviae)。此外,菌株QPX1对阿莫西林、多粘菌素B、磺胺异噁唑、复方新诺明、卡那霉素、吡哌酸、新霉素、庆大霉素、氟苯尼考、链霉素、恩诺沙星、诺氟沙星、奈替米星等抗生素高度敏感。本研究证实豚鼠气单胞菌是南美白对虾黄腿病的病原菌,生产上可选用新霉素、氟苯尼考、恩诺沙星等常规水产用抗生素作为该病的防控用药。     

Effects of florfenicol feeding on diversity and composition of the intestinal microbiota of channel catfish (Ictalurus punctatus)

Intestinal microbiota contributes health of living organisms. Florfenicol is an approved antimicrobial (AM) prescribed for several bacterial fish diseases. The present study investigated the extent to which florfenicol modulates intestinal microbial populations of channel catfish (Ictalurus punctatus). Florfenicol was administered orally to catfish at a standard therapeutic dose (10–15 mg/kg of body weight for 10 days), and the intestinal contents were collected and the 16S rRNA was subjected to Illumina sequencing. Alpha diversity analysis indicated that florfenicol significantly decreased microbiota richness and diversity. Beta diversity reflected a clear separation had occurred between the florfenicol‐fed and control groups. Results indicated a significant increase in the abundance of phylum Proteobacteria (98.97% vs. 79.35% of the population) and decrease in phyla Firmicutes and Bacteroidetes (0.72% and 0.29% vs. 18.04% and 2.53%, respectively) in the florfenicol‐fed fish in comparison with the control fish. At the genus level, unclassified Enterobacteriaceae and Escherichia populations increased in the florfenicol group. In contrast, Plesiomonas, Aeromonas, Lactococcus, Clostridium sensu stricto, Romboutsia, Klebsiella, Turicibacter and Lactobacillus decreased in florfenicol‐fed fish in comparison with the control fish, indicating that intestinal microbiota of catfish was substantially modulated by florfenicol administration. Knowledge of changes in gut microbiota during medicated feed administration is important to improve fish performance and disease management and could enable the development of alternative therapeutic strategies.     

不同健康程度和抗生素氟苯尼考干预下斑石鲷肠道菌群的结构差异

为了研究不同健康程度和抗生素氟苯尼考干预下斑石鲷肠道菌群结构的差异及其与养殖环境中菌群结构的相关性,采用Illumina Hi Seq PE250高通量测序的方法对健康、亚健康、典型黑身病和口服氟苯尼考条件下的斑石鲷肠道、养殖水体和颗粒饵料中的细菌多样性及群落结构进行了分析比较。结果显示,养殖水体中细菌多样性高于肠道和颗粒饵料。不同健康程度及氟苯尼考干预下斑石鲷肠道中细菌均以变形菌门、厚壁菌门和软壁菌门为主,且对应的操作分类单元(OTU)占样品全部OTU的比例均达到85%以上。黑身病的发生可影响斑石鲷肠道中丰度最高的前20种优势细菌种类的排名次序,其中变形菌门中的弧菌属的相对丰度显著增加,且随着弧菌属丰度的增加,斑石鲷的黑身病症状也逐渐加重。饵料中添加氟苯尼考投喂斑石鲷能使患病鱼肠道弧菌属的丰度从60.33%下降到1.29%,较大程度改变了肠道的菌群结构,并证实氟苯尼考有效防治黑身病。其次,养殖水体和颗粒饵料对斑石鲷肠道菌群也有一定影响,且养殖水体的影响高于颗粒饵料。本研究首次报道了斑石鲷肠道菌群结构,其研究结果为今后斑石鲷的健康养殖、疾病防控及其微生态学研究提供了参考依据和技术支撑。     

氟苯尼考对鲁氏耶尔森氏菌体外药效研究

本文研究了氟苯尼考对鲁氏耶尔森氏菌(Yersinia ruckeri)体外药效学,测定了最小抑菌浓度(MIC)、最小杀菌浓度(MBC)、生长动力学曲线和杀菌动力学曲线和抗菌后效应(PAE)及四种培养因子对氟苯尼考体外抑制鲁氏菌活性的影响。结果表明:MIC、MBC和MBC/MIC分别为0.5μg.mL-1、1μg.mL-1和2;鲁氏菌在液体培养基中1h后进入对数生长,大约持续7h;在用药4～6 h达到最大药效。由杀菌曲线可知,氟苯尼考的杀菌功效具有浓度依赖性;在2 MIC、4 MIC和8 MIC时,PAE分别为3.71±0.11、4.54±0.27和5.52±0.23;氟苯尼考对鲁氏菌作用最适pH值为6～8,且二价阳离子(Mg2+)、血清含量及细菌数量小于108时对药效无显著影响。因此,保证药物浓度和作用时间,并配合最适培养条件,是氟苯尼考发挥最高药效的前提条件。     

黄鳝源嗜水气单胞菌DB01分离鉴定及药敏特性研究

从患病的黄鳝(Monopterus albus)体内分离到一株致病菌株DB01,对该菌株进行人工感染、生理生化鉴定及16S r DNA序列分析。结果显示:人工感染黄鳝出现与自然发病相同的症状,表明菌株DB01为发病黄鳝的病原菌。菌株DB01为革兰氏阴性杆菌,无芽孢和荚膜,在兔血平板上能形成明显的β-溶血。序列分析显示,菌株DB01与嗜水气单胞菌(Aeromonas hydrophila)的同源性达99%。药敏试验结果显示,菌株DB01对诺氟沙星、左氧氟沙星、阿奇霉素及氟苯尼考等抗生素高度敏感,五倍子、黄柏、地榆及乌梅等中草药对菌株DB01抑菌作用强。     

豹纹鳃棘鲈类结节症病原的分离鉴定

为查明养殖豹纹鳃棘鲈类结节症的病因,自患病豹纹鳃棘鲈内脏中分离到1株优势菌株061101,人工感染试验证实,该菌具有强毒力,能够引起被感染鱼内脏出现白色结节并死亡,为引起此次豹纹鳃棘鲈类结节症的病原菌。采用形态学、生化特性测定对菌株061101进行鉴定,同时采用细菌16S rRNA通用引物进行PCR扩增得到该菌的16S rRNA基因序列,测序后比对,构建系统发育树。试验结果表明,菌株061101与发光杆菌属中的美人鱼发光杆菌杀鱼亚种基本特征相符;基于16S rRNA基因序列构建的系统发育树将菌株061101与美人鱼发光杆菌杀鱼亚种聚为一支,置信度达100%。据此确定,此次豹纹鳃棘鲈类结节症的病原为美人鱼发光杆菌杀鱼亚种。药敏结果显示,该菌株仅对链霉素(300μg/片)、庆大霉素(120μg/片)敏感,对多黏菌素B、阿洛西林等中度敏感,对氟苯尼考、恩诺沙星、强力霉素等均耐药。     

Evaluation of florfenicol in Atlantic salmon,Salmo salar L.: efficacy against furunculosis due to Aeromonas salmonicida and cold water vibriosis due to Vibrio salmonicida

Two replicated controlled trials were conducted to determine the efficacy of florfenicol against Aeromonas salmonicida and Vibrio salmonicida infections in Atlantic salmon, Salmo salar L., smolts kept in 25‰ salt water. Infection with A. salmonicida was treated with florfenicol, oxolinic acid, oxytetracycline, trimethoprim/sulphadiazine or flumequine, whereas the V. salmonicida infection was treated with florfenicol or oxolinic acid only. A. salmonicida infection was induced by the introduction of cohabitant fish previously inoculated intraperitoneally. Medication started simultaneously in all test tanks on the first day of specific mortality among test fish. V. salmonicida infection was induced by intraperitoneal inoculation of all test fish. Medication started 1 day after infection. Medicated feeds were produced by coating the antibacterials on standard feed pellets, and administered twice daily for 10 consecutive days. With the dose used in the present trials, florfenicol was highly effective in reducing specific mortalities due to both infections. It was slightly more effective than oxolinic acid and trimethoprim/sulphadiazine against A. salmonicida infection. There was no significant difference between florfenicol and oxolinic acid in reducing specific mortalities due to V. salmonicida.     

斑点叉尾(鮰)"腹水症"病原的分离鉴定及体外芽孢杆菌拮抗试验

为了解斑点叉尾(鮰)(Ictalurus punctatus)"腹水症"的发病原因,提高防控技术,试验在佛山市某渔场患典型"腹水症"的病(鮰)上分离出优势菌落,通过形态学观察、生化及分子生物学鉴定确定该细菌为温和气单胞菌(Aeromonas sobria).通过对健康斑点叉尾(鮰)的回归感染实验发现,与原感染鱼发病症状相似,且分离鉴定得到相同病原菌.体外药敏试验结果显示:该温和气单胞菌菌株对恩诺沙星、氟苯尼考等7种药物敏感,而对四环素、强力霉素耐药.本研究还探讨了4种芽孢杆菌对分离的温和气单胞菌的拮抗作用,结果表明地衣芽孢杆菌对该病原的拮抗作用最好.     

Effect of florfenicol and oxytetracycline treatments on the intensive larval culture of the Chilean scallop Argopecten purpuratus (Lamarck, 1819)

The administration of antimicrobials to control bacterial pathologies in Chilean scallop hatcheries is a frequent practice, but their effects on these cultures remained unknown. This study was undertaken to obtain information on the effect of the administration of florfenicol and oxytetracycline on the growth, survival and bacterial content of scallop larvae under farming conditions. Florfenicol‐treated cultures exhibited high survival rates (44% after 17 days of culture), whereas cultures not treated or treated with oxytetracycline collapsed after 11 days of culture. Surprisingly, no significant differences in the heterotrophic (Tukey test; P = 0.226) and Vibrio (Tukey test; P = 0.666) concentrations between the oxytetracycline‐treated and untreated larval cultures were observed. Otherwise, florfenicol administered directly into rearing tanks produced significantly higher larval growth (Tukey test; P = 0.0001) and survival (Tukey test; P = 0.011) than bath treatment. When 2 and 4 mg L^?1 of florfenicol were compared, no significant differences in growth (t‐test; P = 0.4596) and survival (Tukey test; P = 0.057) were observed, suggesting that a concentration of 2 mg L^?1 is sufficient to ensure larval production. The present results demonstrate the efficacy of florfenicol‐based therapy to increase larval survival and growth at commercial scale and prompt the necessity to standardize its use in Chilean scallop hatcheries.