淄博地区猪源产ESBL大肠杆菌的多重耐药分析

为了解淄博地区猪源产ESBL大肠杆菌耐药特点,本研究于2016年4月对淄博地区3个养猪场采集猪粪便棉拭子,分离猪源产ESBL大肠杆菌,14种抗生素药敏片进行药敏检测。共收集236份猪粪便棉拭子样本,通过产ESBL确证试验获得94株产ESBL大肠杆菌,占猪源大肠杆菌的39.8%。所有产ESBL大肠杆菌菌株耐药性较强且呈现多重耐药,对碳青霉烯类药物敏感率较高。猪源产ESBL大肠杆菌分离率高且耐药谱广,给临床中应用抗生素的治疗猪源大肠杆菌病带来很大的障碍。     

鸡源产ESBL大肠杆菌耐药特点分析

为了解鸡源产ESBL大肠杆菌耐药特点,本研究2016年1~3月份采集山东省泰安市两个养鸡场鸡粪便棉拭子,分离并鉴定鸡源产ESBL大肠杆菌,纸片扩散法对16种抗生素进行药敏检测。本研究在69份鸡粪便棉拭子中,分离到60株大肠杆菌,获得46株产ESBL大肠杆菌(占77%)。所有产ESBL大肠杆菌菌株均呈现多重耐药,但碳青霉烯类药物敏感率较高。结果显示,鸡源产ESBL大肠杆菌分离率高,呈现耐药谱广。     

淄博地区鸡源耐氟喹诺酮大肠杆菌的耐药特点

为了解淄博地区鸡源耐氟喹诺酮大肠杆菌的耐药特点及其耐药基因携带特点。本研究于2016年5月对淄博地区两个鸡场粪便棉拭子采集,分离耐头孢噻肟大肠杆菌,并对15种抗生素进行药敏检测。PCR检测qnr A、qnr B、qnr S、aac-(6’)-Ib-cr耐药基因。共收集34份粪便棉拭子,分离14株耐喹诺酮大肠杆菌,分离率47%。所有耐喹诺酮大肠杆菌呈现多重耐药,但都对碳青霉烯类药物敏感。12株菌携带qnr S基因,携带率最高为85.7%。鸡源耐喹诺酮大肠杆菌分离率高耐药谱广,给临床中应用抗生素的治疗带来困难。     

AcrAB-TolC主动外排系统与猪源耐药大肠杆菌多重耐药的相关性

以前期获得的25株猪源耐药大肠杆菌为试验菌株,采用药敏纸片法测定以上分离菌株对氟苯尼考、多西环素、庆大霉素等11种药物的敏感性,并分析其多重耐药表型;采用PCR方法和实时荧光定量PCR方法分别检测25株猪源大肠杆菌中AcrAB-TolC主动外排基因的携带率以及不同耐药数量的多重耐药菌株的外排泵基因arA和acrB的表达量,同时分析其主动外排调控基因marA、soxS、robA和acrR相对表达量的差异,从mRNA水平上探讨外排泵基因表达量和调控因子与大肠杆菌多重耐药性的相关性。结果显示,25株耐药大肠杆菌中acrA、acrB和tolC等3种主动外排基因的携带率分别为68.00%、72.00%和76.00%;acrA、acrB这2种主动外排基因以及调控基因marA和soxS的相对表达量和多重耐药的耐药谱数呈正相关,调控基因acrR的相对表达量和多重耐药的耐药谱数呈负相关;robA调控基因的表达量均低于标准菌株,且与耐药谱数无明显相关性。结果表明,猪源耐药大肠杆菌携带acrA、acrB、tolC等3种基因主动外排基因的携带率较高,且与多重耐药菌株的耐药谱具有相关性;调控因子的表达量亦与多重耐药的耐药谱具有相关性。     

兔源大肠杆菌耐药性检测与分析

采用K-B法对89株兔源大肠杆菌进行了8种β-内酰胺类药物的药敏实验,采用普通PCR法检测全部菌株的ESBLs酶基因和多重PCR法检测AmpC酶基因。结果显示,山东省部分规模化兔场分离的大肠杆菌除对头孢噻肟(CTX)和头孢哌酮(CFP)的耐药率为0之外,对头孢呋辛(CXM)、青霉素G(PEN)、氨苄西林(AMP)、头孢曲松(CRO)、哌拉西林(PIP)的耐药率分别为30.33%、70.79%、65.17%、17.98%和12.36%;耐药基因检测结果显示,89株大肠杆菌中有38株未检出β-内酰胺类药物的耐药基因,占所检菌株的42.70%;44株仅携带一种耐药基因(23株携带产ESBLs酶基因,占25.84%;21株携带产AmpC酶基因,占23.60%);4株携带产ESBLs酶2种基因;2株同时携带产ESBLs酶和AmpC酶3种耐药基因,仅1株同时携带产ESBLs酶和AmpC酶4种耐药基因。结果提示兔源大肠杆菌对β-内酰胺类耐药未产生较为广泛的耐药性。     

重庆市部分养殖场金黄色葡萄球菌耐药性分析及ESBL基因检测

为了解重庆市部分养殖场动物源性金黄色葡萄球菌的耐药及携带超广谱β-内酰胺酶(extended-spectrumβ-lactamases,ESBLs)基因情况,从重庆部分养殖场采集共1 371份样品,经前处理、增菌,划线接种,挑取疑似菌落,PCR扩增金黄色葡萄球菌特异性nuc基因,对分离鉴定的金黄色葡萄球菌进行药物敏感性试验,并检测菌株中携带的ESBL基因。结果显示:从1 371份样品中分离到89株金黄色葡萄球菌,包括25株猪源菌株、32株鸡源菌株、6株牛源菌株、10株羊源菌株和16株兔源菌株。89株菌对青霉素类药物耐药最为严重,其次为四环素类、大环内酯类和喹诺酮类。除2株兔源菌株外,其余分离菌均为多重耐药,耐药数量从2种到21种不等,猪源菌株的多重耐药最为严重。ESBL基因检测结果显示共有86株细菌携带blaTEM-1a基因,携带率高达96.6%。分离的金黄色葡萄球菌菌株耐药严重,且广泛携带TEM-1a型ESBL基因。     

西藏林芝地区牦牛源大肠杆菌的耐药性分析

本研究旨在了解西藏林芝地区牦牛源大肠杆菌的耐药情况,为有效控制牦牛大肠杆菌感染和指导临床合理使用抗菌药物提供依据。从565份牦牛粪便样品中分离到488株大肠杆菌,通过纸片扩散法对菌株进行药物敏感性分析,采用PCR检测菌株所携带的毒力基因、耐药基因以及筛查含有β-内酰胺酶基因的大肠杆菌菌株。结果显示,在488株大肠杆菌分离菌株中,31%(152/488)呈现多重耐药;毒力基因omp A、etr A的检出率较高,分别为30.2%、23.1%;耐药基因bla CTX-M、bla TEM的检出率分别达到27.6%、14.4%;此外,在产β-内酰胺酶的菌株中未发现SHV型。结果表明,西藏林芝地区牦牛大肠杆菌感染较为严重,菌株分离率高达86.4%,但产ESBLs的菌株检出率较低,且菌株耐药性严重,更呈现出多重耐药性。     

养殖废水产ESBLs大肠杆菌多重耐药性及耐药基因检测

为研究养殖废水中产超广谱β-内酰胺酶(ESBLs)大肠杆菌的分布及其多重耐药性与耐药基因携带情况,本研究对泰安市污水处理厂污水中分离的50株产ESBLs大肠杆菌阳性菌株采用纸片扩散法测定其对19种常见药物的耐药表型。针对产ESBLs菌株的耐药基因设计6对特异性引物,对ESBLs阳性菌株采用PCR方法检测其耐药基因。结果显示,50株产ESBLs大肠杆菌对β-内酰胺类抗生素表现出较强的耐药性,其中对氨苄西林、头孢噻吩、头孢噻肟呈100%的耐药性;对非β-内酰胺类抗生素同样呈一定耐药性;并且呈多重耐药性。PCR扩增结果显示,分离菌株均含有bla_(TEM)、bla_(CTX-M)基因,有5株含有qrB基因,32株含有qrS基因,有2株不含blaSHV基因,50株菌株均不含qrA基因。本研究表明:养殖场排放的污水已被产ESBL大肠杆菌严重污染,污水是这些耐药基因重要的存储库。且养殖污水中耐药菌通过污水排放最终进入到水环境中,其耐药基因可能在水环境的细菌之间进一步扩散,导致产ESBLs大肠杆菌表现出多重耐药性,同时这些产ESBL大肠杆菌会反过来再次感染动物,造成耐药菌在动物间的传播,甚至造成严重的感染。本研究对水是这些耐药基因重要的存储库这一结论提供了实验佐证。     

河西走廊地区犊牛腹泻致病性大肠杆菌分离鉴定、毒力因子及耐药性检测

[目的]为了分析河西走廊地区犊牛腹泻致病性大肠杆菌携带毒力基因和耐药性情况,[方法]2020—2021年在河西走廊地区采集患腹泻病犊牛的粪便、肛拭子及肝脏等病料组织279份,采用人工感染试验动物、PCR方法和K-B药敏纸片法分别检测犊牛腹泻性大肠杆菌致病性、毒力因子和耐药性。[结果]结果表明,分离得到了126株大肠杆菌,其中79株犊牛腹泻性大肠杆菌能引起小鼠死亡;分离的79株致病性大肠杆菌的毒力基因crl、irp2、fimH、papC、K88、K99、stx1、stx2检测率在40.5%～100%之间,其他毒力基因检测率在15.2%～34.2%之间;分离的79株致病性大肠杆菌对氨苄西林、阿莫西林、新霉素等8种药物的耐药率在49.4%～96.2%之间,对其他药物的耐药率在5.1%～32.9%之间。[结论]从河西走廊地区患腹泻病犊牛病料组织中分离得到79株致病性大肠杆菌,这些菌株携带多种毒力基因,对临床中常用的抗菌药物产生了耐药性。     

马乳源大肠杆菌的毒力基因检测和耐药性分析

[目的] 了解新疆伊犁地区某马场乳源大肠杆菌的毒力基因携带情况和药物敏感性。[方法] 对采集到的85份马乳进行大肠杆菌的分离纯化、染色镜检、特异性基因phoA的扩增和16S rDNA测序;采用K-B纸片扩散法药敏试验分析马乳源大肠杆菌的耐药性;采用PCR技术检测马乳源大肠杆菌携带的毒力基因、耐药基因及鉴定其所属系统发育群,对大肠杆菌进行生物被膜形成能力检测。[结果] 从85份马乳中分离得到6株大肠杆菌,其中3株为A群,3株为B1群;6株大肠杆菌均对青霉素和替米考星耐药;均携带ibeB、yijP、mat、sodA和csgA毒力基因;均未检测到耐药基因;有4株具有生物膜形成能力。[结论] 对新疆伊犁地区某马场马乳源大肠杆菌进行初步的毒力基因检测和耐药性分析,发现其对青霉素和替米考星耐药严重,并携带多种毒力基因,具有一定的潜在致病风险。     

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.