多杀性巴氏杆菌X73株与P1059株原生质体融合株的构建

将多杀性巴氏杆菌Ｘ７３株（ＰｍＲ、ＴｃＳ）与ｐ１０５９株（ＴｃＲ、ＰｍＳ）作为亲本，在脱氧核糖核酸酶（ＤＮａｓｅ）存在的条件下，以ＰＥＧ作为助融剂，进行原生质体融合，然后于高渗琼脂平板上再生细胞壁，再转种在含四环素（Ｔｃ）和多粘菌素Ｂ（Ｐｍ）的双抗培养基上检出融合株。获得的４个融合株，形态及染色特性、生化反应、毒力等均符合多杀性巴氏杆菌的特性；具有双抗药性和两亲本株的抗原组分，说明两种细菌细胞发生了融合和染色体重组。经多次传代证明融合株是稳定的。     

禽多杀性巴氏杆菌ELISA三种抗原比较研究

禽多杀性巴氏杆菌ＥＬＩＳＡ三种抗原比较研究刘云同郑星道金仁哲顾万钧黄伟（吉林省通化县家畜繁改站·１３４１００）（吉林农业大学动物科学系关于检测禽多杀性巴氏杆菌血清抗体的研究，国外学者是应用凝集反应、间接血凝、酶联免疫吸附试验检测禽多杀性巴氏杆菌弱毒免...     

禽多杀性巴氏杆菌交叉保护因子的研究进展

禽霍乱是危害养禽业的重要传染病之一。疫苗免疫接种是防制该病的重要措施,传统疫苗因禽多杀性巴氏杆菌血清型众多且无交叉保护能力而不能有效控制该病。禽多杀性巴氏杆菌交叉保护因子的发现为研制适合各种血清型禽多杀性巴氏杆菌引起感染的广谱疫苗展现了诱人的前景。本文就禽多杀性巴氏杆菌交叉保护因子研究进展进行了综述。     

天津地区禽多杀性巴氏杆菌分离株血清型鉴定

通过Ｃａｒｔｅｒ氏荚膜型鉴定方法和琼脂扩散试验,对天津地区禽多杀性巴氏杆菌血清型进行鉴定。结果１６株分离菌中１１株为Ａ：１（４）,４株为Ａ：１（３,４）,１株为－：１（４）表明引起天津地区禽霍乱的致病菌与国内报道的以Ａ：１型为主有一定的差异。     

应用聚合酶链反应检测禽多杀性巴氏杆菌的研究

根据基因库中禽巴氏杆菌病原的基因序列（U51470）,设计了一对跨幅为488bp的引物,并用这对引物对11个不同血清型的禽巴氏杆菌标准株、9株地方分离株和5株哺孔动物巴氏杆菌菌株及其它6种禽病病原进行了PCR扩增,结果11个血清型的禽源巴氏杆菌和9株禽巴氏杆菌地方分离株均得到了片段大小与实验设计相一致的PCR扩增产物,而对5个血清型的哺乳动物巴氏杆菌和其它6种禽病病原的扩增结果为阴性。该PCR能检出10pg的禽巴氏杆菌DNA模板。     

我国禽源多杀性巴氏杆菌血清型研究

本试验用Carter的荚膜群鉴定法和Heddlesten的热稳定抗原鉴定法对我国116株禽源多杀性巴氏杆菌进行了血清学分型研究。研究表明,A∶1型是我国最主要的血清型,占69.8%,其次为A∶1(14)型和A∶3(4)型,分别占6.8%和4.3%。并对我国目前使用和试用的8株禽霍乱弱毒菌苗株进行了定型,其中3株为A∶1型,与主要血清型相同,5株与主要血清型不一致。在A∶1型菌株中,大部分菌株的耐热抗原与1型标准血清反应,形成1条沉淀线,部分菌株(9株)形成2条沉淀线,表明在A∶1型菌株中还存在有抗原差异。     

禽源多杀性巴氏杆菌保菌方法研究

通过对禽源多杀性巴氏杆菌Ｐ１０５０株和Ｃ４８－１株及６株田间分离细菌的保存观察试验，表明用脱纤羊血和感染小鼠肝脾组织在－２０℃条件下，禽源多杀性巴氏杆菌可存活２年，用鲜血斜面封盖石蜡油保存法，禽源多杀性巴氏杆菌在４℃条件下可存活３个月，菌株保存前生生物学特性及毒力不发生变化，试验提供的方法对禽霍乱流行病学调查和血清分型研究具有实际意义。     

四种消毒剂对三株禽多杀性巴氏杆菌杀灭效果的试验

实验室实验证明，威岛牌消毒剂，百毒杀，氢氧化钠，甲醛等四种消毒剂在比较低浓度下均可杀灭标准株和地方株禽多杀性巴氏杆菌，且三者抗力无明显差别。     

福建及邻近省份禽源多杀性巴氏杆菌的分离鉴定

本研究收集2007~2013年福建省及邻近省份的疑似禽霍乱病死亡鸡、鸭、鹅,进行细菌分离,PCR进行种和荚膜群的鉴定,琼脂扩散试验鉴定其Heddleston氏耐热菌体抗原型。结果共分离鉴定多杀性巴氏杆菌95株,其中鸭源74株,鸡源17株,鹅源4株。其荚膜群全为A型,1型耐热菌体抗原型占67.4%。与20世纪80年代以来我国已有的报道相同,禽源(不含火鸡)多杀性巴氏杆菌血清型仍然以A:1为主。     

禽多杀巴氏杆菌的交叉保护性研究

经差速和蔗糖密度梯度离心,从Ｐ１０５９感染鸡的血液中提取巴氏杆菌。每羽鸡可提取较纯的菌液约１０ｍｌ,含菌量在１００亿／ｍｌ以上。该菌液灭活后免疫鸡,用异型菌Ｃ４８１交叉攻毒,结果与肝组织苗免疫的一样,均具有５０％的保护率,而Ｐ１０５９攻毒耐过鸡则全保护。结果证明,体内繁殖的巴氏杆菌具有交叉保护性,而体外培养菌则没有。     

乳糖促进大肠杆菌增殖的研究

在普通肉汤和普通琼脂培养基中加入一定量的乳糖,可明显地促进大肠杆菌增殖。用平板计数法,麦氏比浊法及离心称重法,对６株禽源Ｅ．ｃｏｌｉ和２株猪源Ｅ．ｃｏｌｉ培养产物的含菌量,菌泥湿重测定。结果表明;在普通肉汤中加乳糖可使Ｅ．ｃｏｌｉ产量增加约１００％;在普通琼脂中,加乳糖可使Ｅ．ｃｏｌｉ产加２００％以上。     

竹鼠多杀性巴氏杆菌的分离鉴定及药敏试验

从红河州某竹鼠养殖场采集患病竹鼠病灶进行细菌分离培养,并对分离的菌株进行生化鉴定、动物回归试验及药敏试验。结果显示,分离的病原体为多杀性巴氏杆菌,该菌株对青霉素、诺氟沙星、阿米卡星等敏感,对链霉素、红霉素、庆大霉素、氯霉素等耐药。     

仔猪致病性大肠杆菌的分离鉴定与耐药性分析

由湛江市3个养猪场采集到40份仔猪黄痢、白痢腹泻粪便样品,共分离到40株大肠杆菌,其中7株是致病性大肠杆菌,三个猪场致病性大肠杆菌的分离率分别为15.4%、10%和43%。对7株致病性大肠杆菌进行药物敏感性试验,结果表明:它们均对恩诺沙星、菌必治和丁胺卡那霉素敏感,而对复方新诺明、阿莫西林、氨苄青霉素、四环素和庆大霉素的耐药率为100%,对氯霉素、头孢氨苄和痢特灵的耐药率为85.7%,对卡那霉素和链霉素的耐药率为57.1,%对氟哌酸和环丙沙星的耐药率为14.3%。猪场选用较敏感药物来防治仔猪大肠杆菌病,使疫病得到了有效控制。     

大肠杆菌肠毒素ST1-LTB融合基因的高效表达

用限制性核酸内切酶ＥｃｏＲⅠ和ＨｉｎｄⅢ双酶切含大肠杆菌肠毒素ＳＴ１—ＬＴＢ融合基因的质粒ｐＸＳＬＴ１,回收０８４ｋｂ的ＳＴ１—ＬＴＢ融合基因,再将载体ｐＥＴ—２８ｂ（＋）用ＥｃｏＲⅠ和ＨｉｎｄⅢ双酶切,然后将其与ＳＴ１—ＬＴＢ融合基因连接,转化至受体菌ＢＬ２１（ＤＥ３）中。经ＥｃｏＲⅠ、ＨｉｎｄⅢ、ＢａｍＨⅠ酶切反应鉴定重组子质粒,得到了理想重组质粒ｐＸＥＴＳＬＴ１。重组菌株ＢＬ２１（ＤＥ３）（ｐＸＥＴＳＬＴ１）经ＩＰＴＧ诱导后,其表达产物经ＳＤＳ—ＰＡＧＥ和ＥＬＩＳＡ检测,结果表明重组菌株可以高效表达ＳＴ１—ＬＴＢ融合蛋白,该融合蛋白占菌体总蛋白的３３２１％,而且无天然ＳＴ１生物毒性。     

野生草食动物源多杀性巴氏杆菌荚膜分型的研究

采用Carter荚膜群鉴定法对分离于我国黑鹿、白唇鹿、斑马和赤大袋鼠的56株多杀巴氏杆菌进行荚膜血清型鉴定,结果表明：B型占78．6％（44／56）,h型占14．3％（8／56）,D型占3．6％（2／56）,另有2株未能确定型,占3．6％（2／56）。其中荚膜B型是斑马、黑鹿和白唇鹿源多杀性巴氏杆菌的主要血清群,荚膜A型是赤大袋鼠源多杀性巴氏杆菌的主要血清群。黑鹿和白唇鹿源多杀性巴氏杆菌均存在2个血清群。     

Feline intracranial neoplasia: retrospective review of 160 cases (1985-2001)

The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.     

The Prevalence and Intensity of Helminth and Coccidial Infections in Dairy Cattle in Central Kenya

A survey of gastrointestinal parasite infections of young (<6 months old), immature (6–12 months old) and adult (>12 months old) dairy cattle on 16 farms in Kiambu District, Kenya was conducted during a dry season (September 1991 to January 1992) and during a wet season (March to July 1992). The survey was based on monthly coproparasitological examination of cohorts and worm counts in tracer calves. The effects of age, sex, farm and season on the prevalence and intensity of helminth and coccidial infections were determined. Faecal egg and oocyst counts revealed that the overall prevalences were: strongyles (including trichostrongyles) (85.5%), liver flukes (Fasciola gigantica) (34.0%), coccidia (30.9%) and tapeworms (9.6%). Eight species of the protozoan Eimeria were identified, the most prevalent species being E. bovis and E. zuernii. The most prevalent nematode genera were Haemonchus, Cooperia, Oesophagostomum and Trichostrongylus. Season, farm and age of the animals had a significant (p<0.05) influence on the intensity of infection with strongyles, liver flukes and coccidia, whereas the sex of the animals had no significant (p>0.05) effect on the prevalence or intensity of infections. A higher intensity of infection with strongyles and coccidia was found in the wet season than in the dry season (p<0.05). The age-specific intensity was in the following order: for strongyles, immature animals of 6–12 months of age had the highest egg counts, followed by young calves and adults. Calves had significantly (p<0.05) higher oocyst counts than immatures or adults. Liver fluke egg counts did not differ significant (p>0.05) between immatures and adult cattle.     

Hypothalamic dopamine is required for salsolinol‐induced prolactin secretion in goats

The aim of the present study was to clarify the relationship between hypothalamic dopamine (DA) and salsolinol (SAL) for the secretion of prolactin (PRL) in goats. SAL or thyrotropin‐releasing hormone (TRH) was intravenously injected into female goats treated with or without the D₂ DA receptor antagonist haloperidol (Hal), which crosses the blood‐brain barrier, and the PRL‐releasing response to SAL was compared with that to TRH. PRL‐releasing responses to SAL, Hal, and Hal plus SAL were also examined after a pretreatment to augment central DA using carbidopa (Carbi) and L‐dopa. The PRL‐releasing response to Hal alone was greater than that to SAL or TRH alone. The PRL‐releasing response to Hal plus SAL was similar to that of Hal alone. In contrast, the PRL‐releasing response to Hal plus TRH was greater than that to TRH or Hal alone. The treatment with Carbi plus L‐dopa inhibited SAL‐ and Hal‐induced PRL secretion. The inhibition of the PRL‐releasing response to SAL disappeared when SAL was injected with Hal. These results indicate that the mechanisms underlying the SAL‐induced PRL response differ from those of TRH, and suggest that hypothalamic DA and its synthesis is associated in part with SAL‐induced PRL secretion in goats.