动物性食品源大肠杆菌O血清型鉴定及其K88菌毛基因检测

本研究对河北省冀东地区农贸市场和超市采集的生猪肉、生鸡蛋和生羊肉等分离得到的20株大肠杆菌进行大肠杆菌血清型鉴定;并检测不同血清型大肠杆菌的K88菌毛基因。采用常规方法进行大肠杆菌的O血清型鉴定,用PCR方法检测K88菌毛基因。分离鉴定的20株大肠杆菌有7种血清型,包括O38、O78、O88、O11、O107、O91、O9,其中O38、O78为优势血清型菌,均占分离菌株的25%(5/20)。在分离的动物性食品源大肠杆菌中有30%(6/20)的菌株K88菌毛基因扩增呈阳性。结果表明,O78、O38为冀东地区动物性食品源大肠杆菌常见血清型,30%(6/20)的菌株K88菌毛基因扩增阳性。     

禽病原性大肠杆菌Ⅰ型菌毛单克隆抗体的研制及其对分离株的检测

从禽病原性大肠杆菌分离株 TK3 ( O1 )提取 型菌毛免疫 BALB/c小鼠 ,取其脾细胞与小鼠骨髓瘤细胞融合 ,获得 4株能稳定分泌针对 型菌毛的单克隆抗体杂交瘤细胞株 ,分别命名为 a B6 、b G5 、c F3和 c G3。单抗阻断甘露糖敏感血凝试验、免疫胶体金和 Western blot试验证明 ,单抗是 型菌毛特异的。这些单抗培养上清及腹水的 ELISA效价为分别为 1 0 - 2～ 1 0 - 3和 1 0 - 5～ 1 0 - 6 ;腹水的平板凝集价为 1∶ 1 2 8～ 1∶ 2 56。上述4株单抗对 77株带 型菌毛的禽病原性大肠杆菌优势血清型分离株进行了检测 :O1 8分离株阳性率为72 %,O78分离株阳性率为 1 7%,O2分离株阳性率为 3 3 %,O88分离株阳性率 89%,O1 1分离株阳性率为60 %,O2 6分离株阳性率为 3 3 %。表明研制的 型菌毛单抗能检出大多数 O1 8、O88、O1 1分离株的 型菌毛 ,而对 O78、O2、O2 6分离株相应菌毛的检出率较低     

禽致病性大肠杆菌的分离、O血清群鉴定及药物敏感试验

对2005年5月~2016年3月自河北、山东、河南、江苏、陕西、辽宁等省发病鸡场疑似大肠杆菌病的病死鸡病变部位分离的194株禽致病性大肠杆菌进行了生化特性测定、O抗原血清群鉴定及药敏试验。试验用5种大肠杆菌单因子（O1、O2、O57、O65、O78）阳性血清进行O血清群鉴定,确定了124株O血清群,占鉴定菌株数的63.9%（124/194）,其中O1 3株、O2 26株、O57 15株、O65 47株和O78 33株,O65和O78为优势菌株,而O2和O57血清群菌株次之,O1血清群菌株最少。8种药物（氨苄西林、新霉素、多西环素、磺胺间甲氧嘧啶、替米考星、环丙沙星、头孢噻呋和氟苯尼考）的药敏试验结果表明,受试的5株大肠杆菌分离株均对环丙沙星和新霉素敏感,而对其他药物均有不同程度的耐受。本研究结果表明O65、O78、O2和O57血清群高度流行,为进一步研发多价菌苗奠定了基础。     

某定点肉牛屠宰场中非O157致病性STEC的分离鉴定

为了了解新疆伊犁地区肉牛屠宰过程中大肠杆菌的污染情况,检测非O157致病性产志贺毒素大肠杆菌(Shiga toxin-producing Escherichia coli,STEC)的感染情况,本试验采集新疆伊犁地区某定点肉牛屠宰场中屠宰肉牛的粪样和屠宰后的胴体表面拭子,并对样品进行了大肠杆菌的分离鉴定、毒力基因(eae、stx1、stx2)的PCR检测、O157鉴定(rfbE)、ERIC-PCR基因分型和小鼠致病性试验。结果显示,在采集的45份样品中分离鉴定出42株大肠杆菌,分离率为93.3%。其中2株菌株同时编码了毒力基因stx1和stx2,检出率为4.8%,毒力基因eae未被检出。PCR鉴定均为非O157STEC。ERIC-PCR基因分型检测发现,2株菌的基因型非常相似,同源关系密切。对小鼠进行腹腔注射攻毒,攻菌6h后,小鼠开始出现死亡,立即解剖死亡小鼠发现,其肠道出血,肝脏、脾脏、肾脏明显出血肿大,解剖对照小鼠表现正常,表明菌株具有一定的致病性。综上所述,在肉牛屠宰过程中存在大肠杆菌污染,其中粪便中非O157STEC菌株对胴体造成了污染,需要加强控制肉牛的屠宰加工关键环节的环境卫生。     

某定点肉牛屠宰场中非O157致病性STEC的分离鉴定

为了了解新疆伊犁地区肉牛屠宰过程中大肠杆菌的污染情况，检测非O157致病性产志贺毒素大肠杆菌（Shiga toxin-producing Escherichia coli，STEC）的感染情况，本试验采集新疆伊犁地区某定点肉牛屠宰场中屠宰肉牛的粪样和屠宰后的胴体表面拭子，并对样品进行了大肠杆菌的分离鉴定、毒力基因（eae、stx1、stx2）的PCR检测、O157鉴定（rfbE）、ERIC-PCR基因分型和小鼠致病性试验。结果显示，在采集的45份样品中分离鉴定出42株大肠杆菌，分离率为93.3%。其中2株菌株同时编码了毒力基因stx1和stx2，检出率为4.8%，毒力基因eae未被检出。PCR鉴定均为非O157 STEC。ERIC-PCR基因分型检测发现，2株菌的基因型非常相似，同源关系密切。对小鼠进行腹腔注射攻毒，攻菌6 h后，小鼠开始出现死亡，立即解剖死亡小鼠发现，其肠道出血，肝脏、脾脏、肾脏明显出血肿大，解剖对照小鼠表现正常，表明菌株具有一定的致病性。综上所述，在肉牛屠宰过程中存在大肠杆菌污染，其中粪便中非O157 STEC菌株对胴体造成了污染，需要加强控制肉牛的屠宰加工关键环节的环境卫生。     

石河子地区生鲜肉蛋奶大肠杆菌污染情况调查

为了解石河子地区生鲜肉、蛋、奶产品中大肠杆菌的污染情况,本试验选择不同的屠宰场、鸡蛋和牛奶销售地点,无菌采集牛肉、羊肝、鸡肉、猪肉、猪肝、鸡蛋、散装牛奶各100份,通过对样品进行细菌的分离培养、生物学特征和生化特性的鉴定及溶血性观察,结果表明:除鸡蛋中未分离到大肠杆菌外,牛肉、羊肝、鸡肉、猪肉、猪肝和散装牛奶中均分离到了大肠杆菌,且分离率为100%;随机挑选的60株代表菌株中有5株大肠杆菌具有β溶血的特性,其中羊源大肠杆菌有3株,牛源和奶源的大肠杆菌各有1株。由此可知,石河子地区肉类产品及散装牛奶中大肠杆菌的污染情况严重,应当引起相关部门的高度重视。     

泰安地区鸡源致病性大肠杆菌流行病学调查与耐药性分析

正本调查对鸡场采集的疑似鸡大肠杆菌病例的相关病料进行大肠杆菌的分离鉴定,共分离鉴定出14株鸡源大肠杆菌,以微量平板凝集试验鉴定分离菌株的O抗原血清型,分别属于O78、O2和O1等3个血清型,其中O78(6/14)、O2(6/14)为主要流行血清型,占分离菌株总数的85.71%。选取了20种常用治疗肠杆菌病的抗生素对14株鸡源大肠杆菌分离株进行药敏试验,对14株大肠杆菌     

种公鸭精液中大肠杆菌的分离鉴定与药敏试验

本研究从莆田某蛋鸭养殖场无菌采集种公鸭精液进行细菌分离鉴定,并对其分离菌株进行了药敏试验和血清型鉴定。分离鉴定结果表明,分离鉴定了6株鸭大肠杆菌分离株;药敏试验结果表明,6株鸭大肠杆菌分离株对对22种抗生素的敏感程度存在一定的差异,而且存在着多重耐药性,对先锋V、头孢曲松、卡那霉索、壮观霉素、多粘菌素B等5种抗生素敏感;O血清型鉴定结果表明,6株鸭大肠杆菌分离株中4株属于O78血清型,2株属于O1血清型。     

上海地区猪源大肠杆菌血清型及其毒力因子分布调查

对上海地区分离的199株猪源大肠杆菌分离株进行血清型鉴定和毒力因子检测,使用大肠杆菌标准抗O因子血清进行玻片凝集试验;采用普通和多重PCR方法,对分离株进行STa、STb、LT、Stx2e等4种肠毒素和K88、K99、987P、F18、F41等5种黏附素检测。结果:199株猪源大肠杆菌分离株有110株鉴定出血清型,占检测菌株的55.28%,覆盖了30种血清型,优势血清型为O8、O45、O64、O78、O138、O157、O163、O7+O8,占定型菌株的60%。共有32株大肠杆菌检测到毒力因子,阳性率为16.08%,检测出9种毒力因子。其中有21株单独检测到肠毒素,占65.63%,STa和STb+LT阳性的菌株分别为14和4;6株单独检测到黏附素,3株菌株K99阳性;5株同时检测到肠毒素和黏附素。在32株毒力基因阳性的大肠杆菌中,有15株血清型定型,覆盖7种血清型,其中O138、O7+O8与肠毒素STa相关,O8、O45与STb+LT相关。研究表明,上海地区猪源大肠杆菌分离株优势血清型至少覆盖了包括O8、O45、O64、O78、O138、O163等在内的8种血清型;大肠杆菌分离株以产肠毒素为主,主要毒力因子包括黏附素K99和肠毒素STa、STb+LT等。     

大连某奶牛场奶牛乳房炎病原菌分离及鉴定

本试验对大连某奶牛养殖场15头患临床型乳房炎病牛进行病原菌分离、鉴定。使用鉴别培养基对乳样中的大肠杆菌、葡萄球菌、链球菌及沙门氏菌进行分离,并对分离出的大肠杆菌进行血清学“O”抗原检测试验。结果显示,25个乳区的乳样共分离到病原菌37株,其中大肠杆菌15株、链球菌13株、葡萄球菌8株、沙门氏菌1株,乳房炎阳性率为5.2%,乳区阳性率为2.2%;大肠杆菌分离株以O51、O148、O78、O60血清型为主。     

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。     

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。     

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。     

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.     

Mechanism of Action of Probiotic Function of Lactobacilli

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.     

Evaluation of serum concentrations of biomarkers of skeletal metabolism and results of radiography as indicators of severity of osteochondrosis in foals

OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis.