中药单味药及复方对嗜水气单胞菌的体外抑菌作用

本试验用煎煮法提取中药有效成分,采用琼脂平板扩散法探讨了黄连、五倍子、大黄、诃子等中药单味药及中药复方对嗜水气单胞菌(Aeromonas hydrophila)的体外抑菌作用,测定了抑菌圈大小.采用双倍试管稀释法测得了最小抑菌浓度(MIC)和最小杀菌浓度(MBC).试验结果表明,16种中药提取物对嗜水气单胞菌有不同程度的抑制作用,其中五倍子、黄连、诃子、大黄的水提物的抑菌效果最好,MIC值分别为7.81 mg/mL、15,63 mg/mL、31.25 mg/mL、62.50 mg/mL.五倍子作为主药,分别与诃子、黄连、大黄接一定比例组成的复方的MIC分别为3.906 mg/mL、7.813 mg/mL、15.625 mg/mL.通过对筛选的复方与市场上销售的3种成品复方的体外抑菌活性的比较,发现本实验室筛选的复方对嗜水气单胞菌的体外抑菌活性更强.     

大青叶板蓝根等5种清热类中药体外抗伪狂犬病病毒效果

中药具有抗病毒和免疫调节等作用,尤其是对病毒病和慢性疾病的预防和治疗具有独特的优势.部分中药可通过阻断病毒繁殖过程中的吸附、穿入、复制、成熟中的一个环节而直接杀灭病毒,而另一些中药可调节机体平衡,增强机体细胞及体液免疫功能,从而间接抑制病毒增殖;还有一些中药可诱发机体产生干扰素或IL-1等;而且由于中药多为天然药物,药性温和,不良反应少,使开发治疗猪伪狂犬病的中药制剂成为可能[1].     

Antibacterial activity of supernatants of Lactoccocus lactis,Lactobacillus rhamnosus,Pediococcus pentosaceus and curcumin against Aeromonas hydrophila. In vitro study

Veterinary Research Communications - Secretions of beneficial intestinal bacteria can inhibit the growth and biofilm formation of a wide range of microorganisms. Curcumin has shown broad spectrum...     

PEG对嗜水气单胞菌疫苗制备与免疫效果影响的研究

为评价聚乙二醇(PEG)作为超声介质及疫苗佐剂对嗜水气单胞菌疫苗免疫效果的影响,本研究将该疫苗与常规疫苗分别经腹腔注射免疫接种锦鲤成鱼,检测血细胞吞噬百分率、吞噬指数、抗菌活力、抗体效价及免疫保护力等指标,评价疫苗效果.结果表明PEG6000作为佐剂制备的疫苗,其各指标均高于对照组及其他试验组.PEG6000疫苗免疫保护力达到77.8％,高于常规灭活疫苗22.2％,表明PEG6000作为佐剂制备的疫苗效果最好.     

In vivo effect of selected medicinal plants against gastrointestinal nematodes of sheep

Nematode resistance to anthelmintic drugs affects small ruminant production globally. This study evaluated in vivo effects of five plant extracts as alternative nematode treatments. Animals were divided into six groups. Each group was randomly assigned a treatment: Abamectin and Praziquantel (CAP) (positive Control), ethanol extracts of Ananas comosus (AC), Aloe ferox (AF), Allium sativum (AS), Lespedeza cuneata (LC) and Warburgia salutaris (WS). These were applied as an oral dose (100 mg kg^?1 BW), one dose per week per sheep for 42 days (Phase 1). From day 42 sheep were orally dosed for 3 consecutive days with the same treatments in the same groups (Phase 2). Rectal faecal samples were taken every 7 days up to day 63. Eggs per gram of faeces were counted in individual rectal samples, L₃ larval stage was counted in faecal cultures, with four replicates per group. For plant extracts, EPG decreased (P?<?0.001) with time and efficacy of plant increased (P?<?0.001) with time. Ananas comosus and L. cuneata treatments had the highest efficacies of 58 % and 61 %, respectively, in Phase 1; and 77 % and 81 %, respectively, in Phase 2. Continuous treatment with these plants could further reduce nematode parasites and improve host health.     

解淀粉芽孢杆菌的分离鉴定及其对嗜水气单胞菌抑制作用研究

本试验从鲫鱼肠道中分离到1株芽孢杆菌,经生物学特性测定及16S rRNA测序分析,鉴定该分离菌株为高产蛋白酶的解淀粉芽孢杆菌(命名为JX001).对该分离菌进行嗜水气单胞菌体外抑菌试验,结果发现有明显的抑菌圈和抑菌带,说明该分离菌对嗜水气单胞菌具有较强的抑制作用,在养殖水中加入分离菌JX001可防止嗜水气单胞菌的暴发;同时分离菌JX001在生长代谢过程中产生大量的蛋白酶,可有效地促进蛋白质水解,用于蛋白质饲料的降解.     

鲎素对嗜水气单胞菌的抑菌活性及作用机制研究

为探讨鲎素对嗜水气单胞菌的抑杀作用,采用最小抑菌浓度、AB染料、扫描电镜、流式细胞仪和琼脂糖凝胶电泳等方法研究鲎素对嗜水气单胞菌的抗菌活性、杀菌率、胞内紫外物质泄露、膜负电荷数、外部形态结构及胞内基因组DNA的影响。结果表明,鲎素对嗜水气单胞菌的抗菌活性较其他细菌弱;2倍最低杀菌浓度(MBC)鲎素能在短时间内迅速杀死嗜水气单胞菌并导致胞内生物大分子泄漏;扫描电镜发现1倍MBC鲎素能导致轻微的壁膜破损及一些胞内物质渗出和粘连;流式细胞仪结果表明,1倍MBC鲎素能破坏细胞膜的完整性;AB染料测定表明鲎素处理后能改变膜负电荷数;琼脂糖凝胶电泳表明,鲎素能够与嗜水气单胞菌的基因组DNA发生作用,并呈浓度依赖关系,浓度越高对细菌基因组DNA损伤越大。鲎素对嗜水气单胞菌的抑菌活性弱,只有高浓度时才能短时间内导致胞内紫外吸收物质泄露、膜负电荷数发生改变及基因组DNA损伤。     

鳜鱼嗜水气单胞菌的分离与鉴定

在建立和完善北方地区鱼类疫病的流行病学调查研究时,从丹东鸭绿江一网箱养殖场患病鳜鱼中分离到了一株优势菌株。对该菌株进行营养琼脂及绵羊血琼脂培养基培养、革兰氏染色镜检、Vitek细菌鉴定仪鉴定及16SrRNA序列分析比对。经细菌形态学特征分析、生理生化试验及16SrRNA核苷酸序列同源性分析和系统发育树的构建比对,结果表明该分离菌株为嗜水气单胞菌。本研究的开展为有效防控疫病及疫苗制备等方面提供参考和借鉴,同时为开展该疫病的监测、防治和预警,促进鱼类及其产品的进出口贸易,意义十分重大。     

The use of eugenol against Aeromonas hydrophila and its effect on hematological and immunological parameters in silver catfish (Rhamdia quelen)

The aim of this study was to evaluate the activity of eugenol against the fish pathogen Aeromonas hydrophila and eugenol's effect on hematological and natural immune parameters in silver catfish (Rhamdia quelen). In vitro, eugenol showed weak activity against A. hydrophila, but in vivo, at a subinhibitory concentration (10 mg L^?1), it promoted survival in infected silver catfish. Eugenol (50 μg mL^?1) reduced the hemolytic activity of A. hydrophila supernatant in vitro in fish erythrocytes. Subjecting catfish to eugenol baths (5 and 10 mg L^?1) for five days did not alter the hematological and immunological parameters studied in this work. Based on these results, eugenol can be used to treat or prevent bacterial diseases in fish.     

In vivo studies with dimethyldithiocarbamate, a possible new antimicrobial for use against Aspergillus fumigatus in poultry

Dimethyldithiocarbamate (DmDTC), the carbamate analogue, was tested for therapeutic efficacy in a series of in vivo challenge trials using 5- and 10-week-old white leghorn chickens. Challenge organisms were Pasteurella multocida X-73, Escherichia coli O1:K1, and Aspergillus fumigatus. Birds were evaluated for survival rates, lesion scores, and the rate at which the bacteria or mold could be reisolated following challenge. Results showed DmDTC to be ineffective against P. multocida and E. coli at the treatment levels and in the form used in these trials, but DmDTC significantly reduced lesion scores and inhibited the rate of isolation of A. fumigatus compared with untreated infected birds.     

In vitro antimicrobial activity of sulfonamides against some porcine pathogens

The minimal inhibitory concentrations (MIC) of sulfonamides were determined against Bordetella bronchiseptica (n = 10), Pasteurella multocida (n = 10), Haemophilus pleuropneumoniae (n = 20), and Streptococcus suis (n = 10) strains isolated from pigs with atrophic rhinitis, pneumonia, or meningitis. Sulfonamides tested in an agar dilution method were sulfachloropyridazine, sulfadiazine, sulfadimethoxine, sulfamethazine, sulfadoxine, sulfisoxazole, sulfamerazine, sulfamethoxazole, sulfamethoxypyridazine, sulfanilamide, sulfatroxazole, and sulfisomidine. Results indicated that monotherapy of S suis infections with sulfonamides should not be encouraged because the MIC50 of all sulfonamides investigated was greater than 32 micrograms/ml. The MIC50 of the sulfonamides against B bronchiseptica ranged from 0.5 to 8 micrograms/ml, against P multocida from 2 to 32 micrograms/ml, and against H pleuropneumoniae from 8 to 64 micrograms/ml. The MIC50 of sulfachloropyridazine, sulfadiazine, sulfadimethoxine, sulfamerazine, and sulfamethoxazole for the gram-negative bacteria did not exceed 16 micrograms/ml. Among these compounds, sulfamethoxazole had the highest activity. The frequently prescribed sulfamethazine had an overall low antimicrobial activity.     

In vitro antimycoplasmal activity of six Jordanian medicinal plants against three Mycoplasma species

The in vitro effect of six Jordanian traditional medicine plant methanolic extracts were tested against 32 isolates of Mycoplasma species; Mycoplasma mycoides subsp. mycoides LC (6), Mycoplasma capricolum subsp. capricolum (8) and M. putrefaciens (18), all isolated from either nasal swabs or milk, from sheep and goats in different regions in Jordan. All Mycoplasma species showed susceptibility to Artemisia herba-alba and Artemisia arborescens with MIC ranges from 3.125–12.5 mg/ml. Allium sativum and Punica grantum showed limited activity against some Mycoplasma isolates. Olea europea and Citrullus colocynthis showed no in vitro activity against any of the Mycoplasma species tested. Artemisia herba-alba and Artemisia arborescens may therefore be useful for the treatment of mycoplasma infections. The authors are British Civil Servants and as such their work is subject to British Crown Copyright. This means the exclusive copyright for the article cannot be transferred.     

嗜水气单胞菌体外粘附Caco-2细胞对细胞膜生物学特性的影响

采用Caco-2细胞培养模型，研究了嗜水气单胞菌粘附Caco-2肠上皮细胞后时其活力、细胞膜磷脂酶A2（PLA2）、胞浆游离钙浓度、膜通透性和膜流动性的影响。结果显示，细菌粘附后1h，肠上皮细胞活力显著下降，PLA2活性和胞浆游离钙浓度显著增加，细胞外LDH含量和细胞损伤率显著升高（膜通透性异常增加），肠上皮细胞膜荧光，偏振度、膜脂微粘度显著增加（膜流动性降低），且上述指标均随着粘附时间的延长而持续升高或降低。     

In vitro and in vivo efficacy of epsiprantel against Echinococcus granulosus

In vitro, epsiprantel at a concentration of 10 micrograms ml-1 caused tegumental damage and death of protoscoleces, juveniles (seven-day-old) and adult (37-day-old) Echinococcus granulosus. Degenerative changes and death occurred more rapidly in the older parasites. Similarly, epsiprantel was more effective against adult (28-day-old) than seven-day-old experimental infections of E granulosus in dogs. Oral doses of 2.5, 5 and 7.5 mg kg-1 were greater than 96 per cent, 99.9 per cent and 99.99 per cent active, respectively, against mature worms, whereas in seven-day-old infections doses of 5, 7.5 and 10 mg kg-1 produced greater than 94 per cent, 90 per cent and 99.8 per cent reduction in worm burdens, respectively. No side effects from treatment were seen.     

Role of Ichthyophthirius multifiliis in the Infection of Aeromonas hydrophila

Aeromonas hydrophila and Ichthyophthirius multifiliis are important fish pathogens. To clarify their relationship, two host models, goldfish with trauma and those infected with I. multifiliis, were used to study infection kinetics of A. hydrophila 4332 tagged with plasmid pGFPuv (Ah4332(GFP)). The results showed that in fish suffering from ichthyophthiriosis, the bacterial infection process was accelerated and more persistent than in the other groups. It is suggested that I. multifiliis plays an important role in the infection of A. hydrophila. Mechanical trauma caused by I. multifiliis might act as a portal of entry for A. hydrophila present in the water, thereby facilitating the invasion of bacteria. The ectoparasite might also serve as a vector and reservoir of pathogenic bacteria.     

北极狐嗜水气单胞菌的分离与鉴定

从北极狐脏器中分离到一种革兰氏阴性杆菌 ,经培养特征、形态、生理生化、致病力测定及药敏试验证实为嗜水气单胞菌 ,确定该菌为引起狐致死的病原菌