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1.
采用平板对峙法从海南省土壤中分离到5株对香蕉枯萎病有较强拮抗作用的芽孢杆菌,经形态特征及16S rDNA序列将菌株S40鉴定为枯草芽孢杆菌Bacillus subtilis。菌株S40的拮抗试验表明,不同浓度的发酵滤液均可抑制病原菌菌丝生长和孢子的萌发和生长。组培袋装苗实验表明拮抗菌可明显推迟其发病和死亡时间,三种不同处理的相对防治效果分别为71.2%、83.3%和92.4%。  相似文献   

2.
 从健康肉鸡的粪便中分离出一株BF3芽孢杆菌,经培养特征、形态观察、生理生化试验以及16SrDNA序列分析相似度为99%,确定该菌株为枯草芽孢杆菌,对该株芽孢杆菌对肠道致病菌的拮抗作用进行研究。结果表明BF3菌株在培养过程中,可以抑制鸡白痢沙门氏菌和鸡大肠杆菌的生长。拮抗作用的强弱与芽孢杆菌和致病菌的接种时间有关。先接种芽孢杆菌后接种致病菌,拮抗作用最强;芽孢杆菌和致病菌同时接种次之;先接种致病菌后接种芽孢杆菌,拮抗作用最弱。并且BF3菌株代谢产物对鸡白痢沙门氏菌和鸡大肠杆菌具有非常明显的拮抗作用。  相似文献   

3.
枯草芽孢杆菌BHI344培养条件的优化   总被引:1,自引:0,他引:1  
以牛肉膏蛋白胨培养基为初始培养基,探讨了不同培养时间、初始pH值、温度、接种量、碳源、氮源、无机盐源对枯草芽孢杆菌BHI344生长的影响,采用正交试验法优化了培养基的组成。结果表明:菌株BHI344产最大活菌数的培养条件为初始pH值7.6、接种量5%(V/V)、培养温度35℃、培养时间16h、牛肉膏2.0%(W/V)、葡萄糖1.5%(W/V)、氯化钙0.3%(W/V);以此条件培养,BHI344的活菌数能达到2.62×109CFU/mL。  相似文献   

4.
不同芽孢杆菌对雏鸡细菌性腹泻病原菌的体外抑菌试验   总被引:2,自引:1,他引:1  
研究不同芽孢杆菌对雏鸡细菌性腹泻病原菌的体外抑菌作用。采用稀释分离法从不同来源的样品中分离得到芽孢杆菌菌株41株;以3种雏鸡细菌性腹泻病原菌为指示菌,采用牛津杯法进行体外抑菌试验,发现6株菌株对病原菌均具有明显的体外抑菌作用,抑菌效果最好的为菌株B332,其次为菌株D4;经形态特征、生理生化特征和16S rDNA序列分析,菌株D4和B332应分别归属于巨大芽孢杆菌和枯草芽孢杆菌。  相似文献   

5.
为研究南太湖沉积物中可培养放线菌,并筛选具高抗水产病原菌的活性菌株,通过分离培养基分离纯化放线菌,通过形态学特征观察、16S r RNA基因序列比对和系统发育分析对南太湖沉积物中可培养放线菌进行分类鉴定,采用琼脂块法和牛津杯法测试分离菌株及其2种发酵液对3种水产病原菌荧光假单胞菌(Pseudomonas fluorescens)、嗜水气单胞菌(Aeromonas hydrophila)、维氏气单胞菌(Aeromonas veronii)的拮抗作用。从南太湖沉积物中共分离得到160株放线菌菌株,隶属于6个目、9个科和12个属,除优势菌群链霉菌(Streptomyces)外,还分离到小单孢菌属(Micromonospora)、诺卡氏菌属(Nocardia)、北里孢菌属(Kitasatospora)和壤霉菌属(Agromyces)等,通过优良拮抗放线菌初筛,26株放线菌对至少一种水产病原菌具有抑菌活性,通过对初筛有抑菌活性的菌株进行优良拮抗放线菌复筛,9株放线菌对水产病原菌仍具有抑制活性,其中菌株Spr-T-4-14发酵液对3种病原菌具抑菌活性,为后续进一步研究其活性次级代谢产物提供了依据。  相似文献   

6.
猪源气单胞菌分离鉴定及耐药谱检测   总被引:1,自引:0,他引:1  
为调查气单胞菌在我国猪粪便中流行情况及耐药谱,2017年3~7月从河南省4个地区,共采集370份猪粪样品,通过缓冲液蛋白胨水增菌培养后,使用添加有氨苄青霉素的气单胞菌基础培养基选择培养,分离气单胞菌。可疑菌株通过形态特征、生化试验和16SrDNA序列比对进一步鉴定。微量稀释法测定分离菌株对17种抗菌药物耐药谱。结果显示,共分离到11株气单胞菌,分离率为2.97%,其中豚鼠气单胞菌5株(占45.45%),杀鲑气单胞菌2株(占18.18%),中间气单胞菌、嗜水气单胞菌、水生气单胞菌和贝斯特润气单胞菌各1株(各占9.09%);阿莫西林/克拉维酸菌耐药率为100%,磺胺甲恶唑、氟苯尼考耐药率81.82%,阿米卡星、美罗培南敏感率均为100%,除了其中1株气单胞菌,其他菌株对头孢噻呋、头孢曲松、庆大霉素、强力霉素、磷霉素、恩诺沙星均敏感,各菌株均呈多重耐药性。表明我国健康猪粪便中携带气单胞菌,如果造成水源或者食物污染,可能有引起人类或者动物感染的风险,应引起重视。  相似文献   

7.
试验为验证益生菌枯草芽孢杆菌PB6菌株的抑菌谱,采用管碟法将PB6对产气荚膜梭菌、鼠伤寒沙门菌和大肠杆菌等9种病原菌的抑菌作用进行研究。结果表明,PB6菌株的培养液具有较广的抑菌谱,对同为革兰阳性菌的产气荚膜梭菌抑菌效果尤为明显,对大肠杆菌、鼠伤寒沙门菌和金黄色葡萄球菌等常见肠道致病菌亦有不同程度的抑菌作用。另外,PB6菌株对引起鸭传染性浆膜炎的鸭疫里氏杆菌和引起海洋水产动物疾病的弧菌也表现出明显的抑菌性能。  相似文献   

8.
<正> 亲水产气单胞菌病(Aeromonas hy-drophila disease)过去被认为是鱼类的一种重要传染病,但近年来人类和动物发生本病的报道日见增多,已构成严重威胁.一、病原体亲水气单胞菌(Aeromonas hydro-phila,简称Ah,下同)是引起本病的病原菌.该菌隶属干弧菌科气单胞菌属,是一种两端钝圆、单鞭毛、有动力、直形或略弯、单个或偶成短链的革兰氏阴性小杆菌,广泛存在于水、土等自然环境中,其致病菌株产有肠毒素和溶血素,能引起人和动物的急性肠炎与败血症.  相似文献   

9.
框镜鲤致病性维氏气单胞菌的分离鉴定   总被引:8,自引:0,他引:8  
为鉴定一株致框镜鲤发病病原菌的生物学特性,本研究由濒死框镜鲤体内分离到一株细菌CY0806,对形态学、培养特性、理化特性等生物学特性以及药物敏感性和16S rRNA序列进行检测和分析。结果显示:细菌株CY0806为革兰氏阴性菌,其理化特性与维氏气单胞菌基本相同。系统进化树分析表明,细菌株CY0806序列与维氏气单胞菌模式株ATCC35624无差异,同源性为100%,因此,鉴定该菌株CY0806为维氏气单胞菌。药物敏感性试验结果显示,庆大霉素、新霉素等11种药物对细菌株CY0806有较好的抑菌效果。  相似文献   

10.
枯草芽孢杆菌对畜禽常见致病微生物体外拮抗作用的研究   总被引:1,自引:0,他引:1  
采用琼脂扩散法和混菌拮抗培养法,考察枯草芽孢杆菌对畜禽常见致病菌的体外抑制作用,结果表明:枯草芽孢杆菌对大肠杆菌、金黄色葡萄球菌、猪链球菌、肠炎沙门氏菌、奇异变形杆菌、痢疾志贺氏菌的生长均有一定的拮抗作用,对G+致病菌的拮抗作用优于G-致病菌比较小白鼠口服枯草芽孢杆菌制剂的效果,其能引起小白鼠肠道菌群变化,大肠杆菌数量降低。  相似文献   

11.
12.
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。  相似文献   

13.
采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。  相似文献   

14.
本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。  相似文献   

15.
REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.  相似文献   

16.
用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10~0.82μg/g。表明:蜂蜜应视为天然富硒营养品。  相似文献   

17.
乳酸杆菌益生作用机制的研究进展   总被引:2,自引:0,他引:2  
乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和 Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。  相似文献   

18.
为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …  相似文献   

19.
以国际标准强毒R株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离MG,并收集感染鸡所产蛋分离MG。结果表明,人工感染48小时后上、下呼吸道及肺已被全面感染,96小时气囊已被感染,120小时输卵管已能分离到MG,卵巢始终分离不到MG。人工感染鸡自144小时便能在其所产蛋中分离出MG。药物治疗能在72小时内消除感染,油乳剂苗则需24天后逐渐降低蛋内MG分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内MG,但以研制的种蛋浸泡剂药浴效果为最好。  相似文献   

20.
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.  相似文献   

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