传染性喉气管炎病毒王岗株gB基因gC基因和gD基因的真核表达

将传染性喉气管炎病毒(ILTV)王岗(WG)株的gB、gC、gD基因分别克隆到真核表达载体pCAGGS的EcoRⅠ位点，经过酶切、测序分析，筛选鉴定出含有gB、gC、gD基因的重组质粒，分别命名为pCAGG—gB、pCAGG—gC、pCAGG—gD。用质粒纯化试剂盒对重组质粒进行了纯化，将纯化后的质粒转染293T细胞，用间接免疫荧光技术检测了目的蛋白的表达情况。检测结果表明，目的蛋白得到了真实的表达。     

ILTVgB基因重组BCG菌株的构建及其免疫原性

gB基因是传染性喉气管炎病毒(ILTV)的主要保护性抗原基因,本试验以ILTV基因组为模板,利用PCR特异扩增出gB基因,将其连接到含有人结核分枝杆菌启动子hsp70基因和堪萨斯分枝杆菌α信号肽基因的表达载体pRR3上,从而构建了大肠杆菌-分枝杆菌穿梭表达质粒pR-α-gB,再电转化至BCG中,形成重组菌株rBCG-gB.热激后gB蛋白在耻垢分枝杆菌M.smegmatis mc2 155中高效表达,并且通过ELISA和Western blotting检测能够被抗ILTV gB蛋白的单克隆抗体识别.将106CFU的重组菌株rBCG-gB皮下注射免疫3周龄的SPF鸡,分别测定了淋巴细胞指数(SI),吞噬细胞的吞噬能力以及血清中IL-2和IFN-γ的水平,结果表明重组菌株rBCG-gB作为 .载体疫苗具有较强的免疫反应.动物保护试验结果表明,重组菌株rBCG-gB对鸡具有一定的免疫保护效果,能够保护SPF鸡抵抗ILTV强毒株的攻击,血凝抑制试验表明血凝抑制抗体滴度能够显著增加.     

传染性喉气管炎病毒gB基因的主要免疫原片段在大肠杆菌中的表达

利用DNASIS等软件分析传染性喉气管炎病毒（ILTV）WG株的gB蛋白抗原性，筛选出一段抗原性较强的片段，该片段位于邸蛋白的403位至686位氨基酸残基之间。设计引物，引入双酶切位点EcoR Ⅰ，Sal Ⅰ，将目的片段t-gB插入原核表达载体pET30a（＋），得到重组表达质粒pET—tgB并转化到大肠杆菌BL21中，经IPTG诱导后，表达分子量为37ku的融合蛋白His—tgB，表达量占菌体蛋白的40．6％。Westemblot分析表明，His-tgB具有免疫反应性。重组蛋白免疫兔之后可以产生针对ILTVgB的特异性抗体。     

猪白细胞介素-6基因的非融合原核表达研究

用DNA重组技术，将已克隆的猪IL-6基因阅读框片段插入非融合原核表达质粒pBV220中的适当位置，获得重组质粒pBVpIL-6，转化大肠杆菌DH5α后，42℃诱导阳性表达菌。经SDS-PAGE检测发现目的蛋白获得了高效表达，表达量约占总蛋白的20％。表达的蛋白以包涵体形式存在，包涵体经过变性溶解和复性后用酶联免疫吸附试验（ELISA）做定性定量检测。ELISA结果证实了所表达的蛋白为猪IL-6，复性后具有一定活性．并测出了复性后活性蛋白的浓度。     

传染性喉气管炎病毒王岗株糖蛋白gB基因在重组杆状病毒中的表达

将克隆到pUC119中的传染性喉气管炎病毒（ILTV）糖蛋白gB基因，通过EcoRI位点克隆至杆状态病毒转移载体pVL1393中，构建成重组杆状病毒转移载体rpVLgB，将rpVLgB转移载体质粒与杆状态病毒DNA（Bac-N-Blue DNA)共转染Sf9昆虫细胞，经3轮蚀斑纯化，获得重组病毒并命名为rpVL－ILTVgB。PCR方法鉴定证明gB基因正确插入到杆状病毒基因组中，直接免疫荧光试验和Dot－ELISA结果均表明gB基因在重组杆状病毒感染的Sf9昆虫细胞保获得表达，表达的gB蛋白将作为鸡传染性喉气管炎的亚单位疫苗和诊断抗原。     

传染性喉气管炎病毒gB基因的主要免疫原片段在大肠杆菌中的表达

利用DNASIS等软件分析传染性喉气管炎病毒（ILTV）WG株的gB蛋白抗原性，筛选出一段抗原性较强的片段，该片段位于gB蛋白的403位至686位氨基酸残基之间。设计引物，引入双酶切位点EcoR Ⅰ，Sal Ⅰ，将目的片段t—gB插入原核表达载体pET30a（＋），得到重组表达质粒pET-tgB并转化到大肠杆菌BL21中，经IPTG诱导后，表达分子量为37Ku的融合蛋白His—tgB，表达量占菌体蛋白的40．6％。Western blot分析表明，His—tgB具有免疫反应性。重组蛋白免疫兔之后可以产生针对ILTV gB的特异性抗体。     

猪生殖与呼吸综合征病毒M基因和N基因的表达

将猪生殖与呼吸综合征病毒（PRRSV）的M基因和N基因从重组质粒pMD18-T—M—N中亚克隆至pBV220原核表达栽体上，成功构建了重组表达质粒pBVM—N。将pBVM—N转化大肠埃希氏菌DH5α感受态细胞．重组菌经温度敏感诱导表达，其细菌裂解物经SDS—PAGE可检测到分子质量约为19ku的目的蛋白，与M基因表达产物一致；经蛋白质分析软件Bandscan分析，其表达量可达19．1％；Western-blotting分析表明，该重组蛋白可被兔抗PRRSV血清所识别，与预期的M基因表达产物相一致，而N基因未获表达。     

粘质沙雷氏菌几丁质酶ChiA基因的表达及活性分析

将含有几丁质酶A基因的重组质粒pUC-chiA和载体pBV221分别进行EcoR Ⅰ /BamH Ⅰ双酶切,连接chiA和pBV221构建了表达载体pBV-chiA5.42℃在E.coli BL21中诱导表达,用饱和(NH4)2SO4和几丁质亲和柱层析法纯化了目的蛋白,DNS法和溶圈法分析其活性,表明所得蛋白为活性可溶性几丁质酶.     

伊氏锥虫HGPRT基因cDNA的克隆及其在E.coli中的表达

根据引物设计的一般原则，参照伊氏锥虫HGPRT基因的核苷酸序列设计、合成一对引物，PCR扩增伊氏锥虫HGPRT基因cDNA。低熔点琼脂糖回收：PCR产物，并将其克隆至pGEM—T Easy载体中，经酶切、PCR鉴定和序列分析，获得重组中间质粒pGEM／HGPRT。重组中间质粒pGEM／HGPRT经Nco I和Sal I双酶切，回收目的片段HGPRT，以非融合形式插入原核表达质粒pBV220构建表达质粒pBV／HGPRT，转化大肠杆菌DH5a，42℃诱导表达，聚丙烯酰胺凝胶电泳和薄层扫描分析，表达产物HGPRT的分子量约为23kD，与理论推算值相符，表达率占总菌体蛋白的19％，经间接ELISA检测，表达产物能被伊氏锥虫阳性血清所识别。     

猴B病毒gB基因杆状病毒表达载体的构建

根据B病毒E2490株(基因序列AF533768)人工合成猴B病毒gB基因,通过XbaI和EcoRI特异性酶切,将其亚克隆于昆虫杆状病毒表达载体pFastBacHTA,经PCR、酶切及测序鉴定,表明构建了猴B病毒gB基因杆状病毒表达重组质粒pFastHTA-gB。在此基础上,重组质粒转化DH10Bac感受态细胞,经平板抗性筛选,PCR鉴定,表明获得了转座的杆粒,为下一步进行昆虫细胞的转染和以猴B病毒gB蛋白为抗原的猴B病毒ELISA检测试剂盒的研制奠定了基础。     

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.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Laboratory diagnosis of respiratory diseases of cattle

The authors describe the procedure of laboratory diagnosis for bovine respiratory diseases: direct diagnosis by isolation and for identification of bacteria or viruses and indirect diagnosis by serological methods. They specify the restraints and limits of this diagnosis and the significance results which are obtained and connected with knowledge of anamnestic information.     

The effect of peri-parturient anthelmintic treatment on the productivity of dairy cattle in subtropical western India

Trials with fenbendazole (Panacur, Hoechst India Ltd) were carried out on two commercial farms in subtropical western India to study the response and economics of nematode treatment in adult dairy cows. Milk yield, lactation length, time to first oestrus and worm egg output were monitored in treated and control groups. Treatment reduced the egg count considerably. Treated cows produced 142 litres more milk over 100 days (p<0.05), with extension of lactation length and advancement of time to first oestrus. The economic gain in terms of milk yield far outweighed the cost of anthelmintic used.     

An Evaluation of the Acceptability as Forage of Some Nutritive and Antinutritive Components and of the Dry Matter Degradation Profiles of Five Species of Ficus

The suitability of five species of Ficus, F. mucoso, F. thonningii, F. polita, F. religiosa and F. benjamina, for feeding ruminant livestock was studied. The nutritive and antinutritive components were determined and the acceptability of the forages to livestock was assessed using a cafeteria method in 8 adult small ruminants. Also, the degradation potential of the dry matter of the five Ficus species was investigated using 3 fistulated sheep. The crude protein (CP) content of the Ficus species varied significantly (p < 0.05), ranging from 130 to 180 g/kg DM. The content of neutral detergent fibre (NDF) also varied significantly (p < 0.05), ranging from 650 to 710 g/kg DM. The organic matter (OM) contents did not differ significantly (p > 0.05), having a mean value of 916 g/kg DM. The concentrations of tannin, saponin, phytic acid and oxalic acid were low. The acceptability of the forage was similar for four of the species but poor for F. polita. The extent of DM degradation varied significant among the Ficus species, the ranking order being F. benjamina > F. thonningii > F. mucoso > F. religiosa > F. polita.