腹泻羔羊中大肠杆菌的分离鉴定及耐药基因检测分析

为了解我省羔羊腹泻性大肠杆菌的耐药性并检测其相关耐药基因的分布,本研究从患腹泻的不同羔羊中分离到14株大肠杆菌,经过分离培养鉴定后,对六大类抗菌药物的耐药基因进行PCR扩增鉴定分析。结果显示,14株大肠杆菌对喹诺酮类和β-内酰胺类抗生素的耐药基因携带率较高,分别为100.00%和71.43%,GyrA/GyrB/ParC喹诺酮类耐药基因是抗生素耐药基因中最为流行的基因型,β-内酰胺类耐药基因型TEM/SHV(71.43%)的检出率较高,四环素类耐药基因型TetC(71.43%)、TetA(57.14%)的检出率较高,氯霉素类耐药基因型Cat(57.14%)检出率较高,磺胺类耐药基因型Sul1/Sul2/Sul3(42.86%)中等检出率;氨基糖苷类耐药基因型aphA3/aadA/aacC2(28.57%)和aacC4(0.00)的检出率较低。结果表明,本次分离的羔羊腹泻性大肠杆菌的耐药性非常严重,同时存在多重耐药现象,提示养殖场应合理使用抗生素。     

长春地区猪源大肠杆菌的分离鉴定和耐药性分析

为了解吉林省长春地区猪源大肠杆菌的耐药情况,于2013年采集318份猪源样品,分离鉴定大肠杆菌275株。以氨苄西林、头孢噻肟等15种药物进行了药物敏感性实验,多重 PCR 方法进行系统进化分群。结果表明,大肠杆菌分离株对四环素、氨苄西林和磺胺甲基异恶唑耐药最严重（83.63%、52.72%、51.27%）,全部菌株对美洛培南、多粘菌素敏感,其中176 株菌表现为对3类以上抗生素的多重耐药（64.00%）。从仔猪腹泻样品分离大肠杆菌对β-内酰胺类抗生素、喹诺酮类抗生素、四环素、氯霉素及磺胺甲基异恶唑的耐药率显著高于健康猪和猪肉样品分离株的耐药率。大肠杆菌分离株主要为 A 群和 B1群。研究获得了吉林长春地区猪源大肠杆菌耐药性的基本流行病学数据,为指导养殖业的临床用药及耐药性监测提供了依据。     

羊奇异变形杆菌的分离鉴定及药敏试验

为查明宁夏地区某羊场羔羊腹泻的发病原因并选择敏感药物用于治疗,从患病羔羊粪便中分离出4株细菌,进行形态特征、培养特性、16S rRNA测序、VITEK微生物鉴定系统鉴定、致病性试验及药敏试验。结果显示,分离菌为奇异变形杆菌。动物试验表明,4株奇异变形杆菌对小鼠具有很强的致病性。药敏试验表明,4株奇异变形杆菌对氨基糖甙类抗生素(阿米卡星、卡那霉素、链霉素)、氟苯尼考及头孢菌素类抗生素敏感,而对大环内酯类(红霉素和克林霉素)、复方新诺明、恩诺沙星全部耐药。对青霉素类(哌拉西林、氨苄西林、阿莫西林)、喹诺酮类(环丙沙星、氧氟沙星、诺氟沙星)、四环素、万古霉素、庆大霉素呈现不同程度的耐药。结果表明,该4株奇异变形杆菌具有较强的致病力和多重耐药性,可能是此次羔羊腹泻的致病菌,治疗首选氨基糖甙类、氟苯尼考及头孢菌素类抗生素。     

小肠结肠炎耶尔森菌对磺胺类和β-内酰胺类抗生素的耐药性研究

为了探讨12株小肠结肠炎耶尔森菌对磺胺类和β-内酰胺类抗生素的耐药性,试验采用标准K-B纸片扩散法检测该菌对磺胺类和β-内酰胺类抗生素的耐药表型,并采用PCR法检测磺胺类耐药基因(sul1、sul2、sul3基因)和β-内酰胺类耐药基因(TEM基因)。结果表明:头孢噻吩、复方新诺明和磺胺异唑治疗效果较差,耐药率分别高达58.3%、66.7%、58.3%,但先锋霉素Ⅴ抑菌效果较好,头孢菌素次之;在菌株中检测出磺胺类耐药基因sul1、sul2和β-内酰胺类耐药基因TEM,其检出率分别为91.7%、100%、75.0%,而sul3基因未检出。     

引起仔猪当前腹泻难治的病菌分析及药敏试验

采用实验室方法分离鉴定了引起猪腹泻的细菌,并对分离菌进行超广谱β-内酰胺酶（ESBLs）检测和对24种抗菌药、5种复方药的敏感性测定。结果显示,分离细菌为大肠杆菌、沙门氏菌、志贺氏菌、奇异变形杆菌,有的且产生ESBLs。药敏试验结果表明该菌对兽医临床中常用的β-内酰胺类抗生素、氟喹诺酮类、氯霉素类、氨基糖苷类等均产生耐药;对粘杆菌素、亚胺培南、美罗培南敏感,β-内酰胺类药物与酶抑制剂联用能使药物对细菌的最低抑菌浓度（M ICs）降低,因此复方β-内酰胺类药物是治疗猪腹泻的有效措施之一。     

仔猪腹泻性大肠杆菌多黏菌素耐药基因mcr-1筛查及其多重耐药基因检测

为了摸清四川地区致仔猪腹泻性大肠杆菌多黏菌素耐药基因mcr-1流行状况及阳性菌株多重耐药基因携带情况,试验采用含多黏菌素E(2μg/mL)的伊红美蓝琼脂培养基筛选多黏菌素E耐药性大肠杆菌,并通过PCR方法检测多黏菌素E耐药基因mcr-1及mcr-1阳性菌株的β-内酰胺酶类、磺胺类、四环素、喹诺酮类、氯霉素类等多重耐药基因的共存状况。结果表明:获得的84株多黏菌素E耐药性大肠杆菌中有49株携带mcr-1耐药基因,阳性率为58.33%。49株mcr-1阳性菌株中磺胺类耐药基因sul1、sul2、sul3检出率为(100%,49/49);氯霉素类耐药基因FLOR检出率为(100%,49/49);四环素类耐药基因tetA的检出率最高(100%,49/49),其次为tetM(63.27%,31/49);β-内酰胺酶类耐药基因以bla_(TEM)与bla_(CMY)为主,检出率分别为75.51(37/49)和61.22%(30/49);喹诺酮类耐药基因以qnrS(87.76%,43/49)、acc-ib-cr(61.22%,30/49)、oqxAB(75.51%,37/49)为主,而qnrA、qnrC、qnrD的检出率均为0。说明携带多黏菌素E耐药基因mcr-1的阳性菌株的多重耐药情况非常严重,从而导致耐药基因的广泛存在以及高水平的传播,威胁人类的健康。     

泰州地区致仔猪腹泻奇异变形杆菌鉴定及其毒力基因与耐药性检测

为了分析泰州地区致仔猪腹泻奇异变形杆菌致病性、毒力基因及耐药性,试验从泰州地区规模化养殖场采集腹泻仔猪粪便、肛拭子等114样品,分离得到42株奇异变形杆菌,采用PCR法和K-B药敏纸片法对分离的42株奇异变形杆菌进行毒力基因与耐药性检测。结果表明,42株奇异变形杆菌毒力基因zapA、pmfA检出率最高,检出率分别为95.2%、92.9%,毒力基因ureC、mrpA、atfC检测出率在40.5%～50.0%之间;42株奇异变形杆菌对阿莫西林、大观霉素、氨苄西林等11种药物耐药率在66.7%以上,对头孢噻呋、头孢噻肟、恩诺沙星等5种药物耐药率在11.9%～26.2%之间,说明了该地区分离的致仔猪腹泻奇异变形杆菌携带多种毒力基因,耐药性严重。本试验为该地区分离的致仔猪腹泻奇异变形杆菌感染的防控提供参考依据。     

鸡源致病性奇异变形杆菌的分离鉴定与遗传进化分析

为了解鸡源奇异变形杆菌的耐药情况、致病力和遗传特征,本试验从凉山地区分离得到2株细菌(YLF1、WS),通过培养特征、镜检特征和16SrRNA序列测定对分离菌进行鉴定及致病性试验;采用(K-B)法检测分离菌对14种常用抗生素(包括β-内酰胺类、头孢烯类、氨基糖苷类、四环素类、氟喹诺酮类、大环内酯类)的敏感性;并与GenBank中公布的21种不同来源的变形杆菌16SrRNA基因序列进行遗传进化分析。结果表明,YLF1、WS菌株均具有迁徙性和β-溶血生长特征,镜检为革兰氏阴性长短不一的杆菌或球菌,经16SrRNA基因鉴定与GenBank中奇异变形杆菌同源性均在99%以上,YLF1、WS菌株确定为奇异变形杆菌,均表现为多重耐药,耐药率分别为78.6%(11/14)和71.4%(10/14);雏鸡致死率均为80%;YLF1、WS菌株与日本人体分离株、中国新疆黄牛分离株和中国广东土壤分离株同源性最高,达99.9%;与来自中国河南、中国新疆及印度的鸡源奇异变形杆菌同源性较高(98.9%~99.3%),遗传关系密切。表明凉山地区鸡群中存在奇异变形杆菌感染,分离株有较高的致病力和较强的耐药性,也提示分离菌可能来源于环境、感染鸡或其他动物,同时存在人畜共患的潜在危险。     

奇异变形杆菌引发猕猴腹泻暴发流行的调查研究

从一群发生急性腹泻的猕猴脏器及粪便样本中分离到多株具有致病性的奇异变形杆菌。分离菌含有 Xk 抗原 ,对青霉素、氯霉素、庆大霉素等抗生素耐药。猕猴感染奇异变形杆菌时 ,结肠比盲肠出血更严重 ,实质器官特别是肝脏和脾脏有明显的瘀血斑。环境的改变、饲养管理不善、滥用抗菌药物等因素均可能导致猕猴奇异变形杆菌性腹泻的暴发流行     

北京地区犬猫尿源奇异变形杆菌耐药性及生物被膜形成能力分析

为调查北京地区犬猫尿源奇异变形杆菌对临床常用抗菌药的耐药现状,并分析其对β-内酰胺类药物的主要耐药机制,本试验于2018—2019年采集北京地区16只犬和13只猫的符合菌尿标准的尿液样本,以及264株犬源和152株猫源尿液中未鉴定细菌分离株;分离鉴定奇异变形杆菌,检测其对临床常用的12种抗菌药的耐药性,并分析奇异变形杆菌携带β-内酰胺酶的情况和生物被膜形成能力。结果显示,共分离获得44株犬源(15.7%)和5株猫源(3.0%)奇异变形杆菌。奇异变形杆菌分离株对阿奇霉素和多西环素耐药率均为98.0%,对β-内酰胺类药物耐药率为6.1%～73.5%,多重耐药率为79.6%。28株分离株携带超广谱β-内酰胺酶(ESBLs),阳性率为57.1%,主要基因型为bla_TEM型、bla_CTX-M-9型和bla_OXA-1型;1株分离株携带头孢菌素酶(AmpC),基因型为bla_CMY-2型。产ESBLs菌株对氨苄西林、氯霉素、头孢吡肟、头孢曲松和庆大霉素的耐药率显著高于非产ESBLs菌株的耐药率(P<0.05)...     

癸氧喹酯干混悬剂含量测定的改进

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。     

商会自治的基石——商会自治规范研究

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。     

猪毛色遗传的研究进展

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。     

中华人民共和国农业部公告 第267号

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。 …     

鸡败血支原体垂直传播模式及其阻断方法

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。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

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.     

不同样本商品蜂蜜中硒含量的测定

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。     

乳酸杆菌益生作用机制的研究进展

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。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

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.