中华鳖源致病性产吲哚金黄杆菌分离、鉴定及药敏特性分析

对患病中华鳖(Pelodiscus sinensis)进行病原分离、鉴定及药敏实验,从患病中华鳖皮肤、肝肾脾重要器官分离纯化病原菌,经理化特性测定及16S r RNA序列分析对其进行鉴定及人工感染试验,并利用K-B及二倍稀释法进行药敏特性分析。结果表明分离株J22是为中华鳖腐皮病病原,其对中华鳖的LD50为3.30×104 CFU/g。J22株理化特性与产吲哚金黄杆菌(Chryseobacterium indologenes)一致,16S r RNA序列与产吲哚金黄杆菌同源性为99%,综合判定J22株是产吲哚金黄杆菌。分离株对新霉素、庆大霉素及阿莫西林等12种抗生素高度敏感,对氟苯尼考及多西环素等抗生素耐药;二氧化氯、漂白粉及高铁酸钾对分离株消毒效果较好。分离菌株J22是中华鳖病原菌,养殖时可选用庆大霉素、新霉素或者阿莫西林内服,配合使用二氧化氯、漂白粉及高铁酸钾等外用进行防控。

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。

中华绒螯蟹致病性弗氏柠檬酸杆菌的分离鉴定及其药敏特性

【目的】明确中华绒螯蟹黑鳃病的病原菌及其药敏特性,为该病的临床诊断和防控提供科学依据。【方法】采用传统方法从患黑鳃病的中华绒螯蟹肝胰腺组织中分离病原菌,通过人工回归感染试验确定病原菌的致病性,利用API 20E细菌鉴定系统和16S rRNA序列分析对病原菌进行鉴定,并以K-B药敏纸片扩散法测定其药敏特性。【结果】从患黑鳃病的中华绒螯蟹肝胰腺中共分离获得4株疑似病原菌株(C1、C2、C3和C4),人工回归感染试验结果表明,仅C1菌株感染中华绒螯蟹后出现死亡,死亡率达90%,且试验中华绒螯蟹出现黑鳃、肝胰腺呈浅黄色的病症,与自然发病的症状基本一致。依据C1菌株的生理生化特性及16S rRNA序列分析结果,可确定C1菌株为弗氏柠檬酸杆菌(Citrobacter freundii),其对健康中华绒螯蟹的半数致死剂量(LD50)为2.85×105 CFU/mL。药敏试验结果表明,C1菌株对新霉素、阿米卡星、庆大霉素、链霉素、多西环素、四环素、复方新诺明、氧氟沙星和恩诺沙星等9种抗生素高度敏感,对多粘菌素B中度敏感,对氨苄西林、羧苄青霉素和万古霉素3种抗生素已产生耐药性(不敏感)。【结论】弗氏柠檬酸杆菌感染可引起中华绒螯蟹黑鳃病,且对中华绒螯蟹具有较强毒力,实际养殖生产中可选用新霉素、多西环素等渔用抗生素进行防治。

Development of a Kit Choosing Medicine Rapidly for Maricultural Bacteriosis

[ Objective] This study aimed to develop a kit to rapidly choose an appropriate medicine for maricultural bactedosis. [ Method] By screening enriched bacteria, solid medium and medicine and comparing effects of rapidly choosing medicine, a kit that could pick up the right medicine quickly for mariculture bacteriosis was created. [Result] The pilot test in some regions showed the kit had ideal yesalts and was easy to operate. [ Conclusion] The kit, a convenient and useful kit to detect drug sensitivity, can help users select effective drugs from many common medicines rapidly and accurately, and it is mainly suitable to use in the rapid selection of an appropriate medicine for maricultural bacteriosis.

Preliminary Studies of Aeromonas hydrophila Diseases in Rana spinosa David and Whole Bacteria Inactivated Vaccine Preparation Method

[Objective]In order to carriy on effective medication and immune prevention and control,pathogen and etiology of a Rana spinosa David disease in a Rana spinosa David breeding company in Zhejiang was researched from 2009 to 2010. [Methods]Conventional bacteria separation and purification technology was used to purify pathogenic bacteria,regression infection and toxicity test was used to determine its virulence,physiological and biochemical and molecular biology identification was carried out to the the pathogen,k- b paper method was adopted for the susceptibility test,normal paraffin wax flaking technology was used for pathology observations,finally,the inactivation conditions of pathogenic bacteria was explored. [Results]The pathogenic bacteria separated from sick Rana spinosa David body had Median Lethal Concentration（ LC 50） of 5.62 ×105 cfu / ml; the strain was identified as Aeromonas hydrophila by ATB bacteria identification instrument and 16 s rRNA sequence analysis（ GenBank login number： HQ322682）; histopathology observation results showed that the disease had main symptoms of the liver and kidney damage,inflammatory cells increase. Susceptibility test showed that the strain was highly sensitive to gentamicin,norfloxacin,florfenicol,enrofloxacin etc. [Conclusions]1% formaldehyde could well inactivate the pathogenic bacteria at 60 ℃ for 24 h,which would provide technical reference for whole bacteria inactivated vaccine preparation.