猪瘟病毒保护性抗原E2蛋白单抗的制备及其抗原表位的初步分析

应用大肠杆菌表达的猪瘟病毒主要保护性 E2抗原决定簇蛋白和全长 E2基因构建的 DNA疫苗免疫 BAL B/c小鼠。取免疫小鼠脾细胞与 SP2 /0骨髓瘤细胞进行融合 ,经克隆和间接 EL ISA筛选 ,获得了 A11、B2、E3、H6、D5、D86株稳定分泌抗猪瘟病毒 E2蛋白单克隆抗体 (Mc Ab)的杂交瘤细胞株。它们的腹水效价在 1∶ 80 0～ 1∶ 2 10 0 0 0之间。抗体类型鉴定结果表明 ,A11、E3、H6、D5和 D8为 Ig M类型 ,B2为 Ig G类型。随后用蛋白 A凝胶层析法和 PEG沉淀法分别纯化了 Ig G和 Ig M单抗。对纯化单抗进行的抗原识别表位研究结果初步表明 ,6株单抗可能识别 3种不同的E2抗原表位。     

两株抗猪伪狂犬病毒的单克隆抗体制备与鉴定

采用猪伪狂犬病毒(PRV)ZJ01株纯化病毒免疫BALB/c小鼠,利用融合细胞技术和间接ELISA抗体筛选技术,制备并获得2株能稳定分泌抗PRV单克隆抗体的杂交瘤细胞株2B3和5C10,其中,2B3单抗为Ig G2a亚类,5C10为Ig G1亚类,轻链均为κ链。间接免疫荧光检测结果表明,2株单克隆抗体均能与PRV发生特异性反应。Western-blot结果表明,2B3单抗针对PRV g C蛋白,5C10单抗针对PRV g E蛋白。本研究为建立快速检测伪狂犬病毒感染的免疫学方法奠定了基础。     

猪口蹄疫病毒抗原位点及其抗原性差异分析

为了分析 3株猪口蹄疫病毒 ( FMDV- B、D、S)的抗原位点 ,采用 5株具有 EL ISA反应特性的抗猪口蹄疫病毒的单克隆抗体 ( Mc Ab- A6、F9、G17、G5 2、S2 5 ) ,通过 EL ISA试验分别测定 3个抗原的最适包被浓度以及 5株单抗对各抗原的饱和工作浓度。 EL ISA叠加试验的增值结果表明 ,5株 Mc Ab分别针对 4个不同的抗原位点 ,其中 Mc Ab- A6和 F9识别同一个抗原位点。FMDV- B株含有这 4个不同抗原位点 ,而 FMDV- D、S株只有 3个抗原位点 ,没有 Mc Ab-A6、F9识别的抗原位点。根据抗原位点差异 ,可以将 3个毒株分成 2个不同组     

马立克氏病病毒囊膜糖蛋白B基因原核细胞表达产物单克隆抗体的制备

用大肠杆菌 BL2 1表达了马立克氏病病毒 (MDV)强毒 GA株的囊膜糖蛋白 B(g B)基因 ,通过 SDS- PAGE电泳分离表达蛋白条带 ,切下并碾碎后作为免疫原制备单克隆抗体。通过 EL ISA和间接免疫荧光试验 (IFA) ,得到 1株阳性单克隆抗体杂交瘤细胞株 7C8。该单抗腹水的 EL ISA效价为 1∶ 2 1 2 ,IFA效价为 1∶ 80 0 ,与 MDV不同致病型毒株CVI988、GA、RB1B、MD11、6 48A株感染的鸡胚成纤维细胞 (CEF)均呈 IFA阳性。1∶ 10 0稀释时与 GA株感染的 CEF在斑点酶联免疫吸附试验 (dot- EL ISA)中呈阳性。     

狂犬病病毒糖蛋白单克隆抗体的制备

用狂犬病病毒BD06株脑毒免疫BALB/c小鼠,制备G蛋白单克隆抗体。将灭活的BD06脑毒免疫BALB/c小鼠,取其脾细胞与骨髓瘤细胞(SP2/0)进行融合,通过间接ELISA法和荧光抗体病毒中和试验法进行4轮筛选,获得6F12、1B12共2株具有中和活性的糖蛋白单克隆抗体的杂交瘤细胞。通过Western blotting分析和直接免疫荧光检测结果显示,获得一株针对狂犬病病毒糖蛋白构象表位的单抗6F12和一株针对糖蛋白线性表位的单抗1B12。小鼠中和试验结果显示,两株杂交瘤细胞分泌的抗体均具有狂犬病病毒中和活性。结果表明,获得了两株针对狂犬病病毒G蛋白不同抗原表位的中和活性单克隆抗体,为狂犬病病毒特性研究和检测奠定了基础。     

O型口蹄疫泛亚毒株单克隆抗体的制备及抗原表位差异分析

用纯化的O型口蹄疫泛亚毒株免疫BALB/c小鼠,取免疫小鼠脾细胞与SP 2/0骨髓瘤细胞进行融合,经3次克隆和间接EL ISA筛选,获得了ⅢA 11、ⅢC 3和ⅢF 10 3株稳定分泌单克隆抗体的杂交瘤细胞株。通过间接EL ISA测定,单抗效价为:细胞培养上清1∶160~1∶640,腹水为1∶5×104~1∶4×105;经EL ISA法测定,3株单克隆抗体均与泛亚株VP 1蛋白反应,而不与A型口蹄疫病毒VP 1蛋白反应;单抗的亚类鉴定结果表明,ⅢA 11和ⅢF 10分泌的抗体为IgG 1亚类,ⅢC 3分泌的抗体为IgG 2b亚类。单克隆抗体抗原识别位点分析结果表明,ⅢA 11与另外2种单克隆抗体的识别位点不同,而ⅢC 3和ⅢF 10的识别位点相近。     

猪伪狂犬病病毒变异毒株gE和gB蛋白单克隆抗体的制备与鉴定

为建立猪伪狂犬病病毒(PRV)疫苗免疫抗体与病毒感染抗体鉴别诊断方法,分别以PRV变异毒株的gE或gB重组蛋白免疫BALB/c小鼠,将免疫小鼠脾细胞与SP2/0骨髓瘤细胞进行融合,经免疫过氧化物酶单层细胞试验(IPMA)和酶联免疫吸附试验(ELISA)筛选所需单克隆抗体,获得6株抗PRV gE蛋白的单抗(3E6、7E1、7C5、10C3、15C1、14C1)和6株抗PRV gB蛋白的单抗(1C1、5D2、2F11、5G8、10C7、8H5)。IPMA检测结果显示,gE蛋白单抗能识别PRV变异毒株,但不识别疫苗株;而gB蛋白单抗可同时识别PRV变异毒株和疫苗株。gE单抗10C3和gB单抗10C7的ELISA效价和IPMA效价均分别达1∶5×10~(5.0)和1∶8×10~(3.0)以上。所筛选出的单抗均不与猪圆环病毒2型(PCV2)、猪繁殖与呼吸综合征病毒(PRRSV)、猪瘟病毒(CSFV)、猪流行性腹泻病毒(PEDV)、流行性乙型脑炎病毒(JEV)等其他常见病毒发生交叉反应。gE蛋白和gB蛋白的表达及单抗的制备为PRV感染抗体与疫苗免疫抗体鉴别诊断(DIVA)试纸的研发奠定基础。     

猪细小病毒核衣壳VP2蛋白单克隆抗体的制备及部分特性鉴定

以纯化的PPV重组VP2蛋白免疫BALB/c小鼠,通过细胞融合技术,间接ELISA筛选和3次以上细胞克隆,获得了5株稳定分泌抗PPV VP2蛋白单克隆抗体杂交瘤细胞株,分别命名为2D5、1F11、2B4、3C8、1 H3。其染色体平均数均为87～102条,分泌抗体亚类4株为Ig M类,1株为IgG类,Western blot检测表明,5株单抗均识别猪细小病毒VP2蛋白;间接免疫荧光鉴定表明,5株单抗均与PPV全病毒发生反应;间接ELISA鉴定与其他相关病毒的交叉反应性表明,制备的5株单抗不与TEGV、PRV和PEDV反应,表明所制备的抗体与猪细小病毒具有较强的特异性反应。     

猪伪狂犬病病毒HeN1株gB蛋白单克隆抗体的制备及B细胞线性表位鉴定

为制备抗猪伪狂犬病病毒(PRV)gB蛋白的单克隆抗体(MAb),本研究将PRV HeN1株全病毒免疫BALB/c小鼠,取免疫后小鼠的脾细胞与骨髓瘤细胞SP2/0融合,用间接免疫荧光方法筛选,获得了一株稳定分泌抗PRV g B蛋白的杂交瘤细胞株1E7。Western blot结果显示,MAb 1E7与PRV全病毒和真核表达的g B蛋白均能够反应。阻断ELISA试验显示MAb 1E7与PRV的结合可以被猪阳性血清阻断。抗体亚类鉴定显示MAb 1E7的重链为Ig G2b亚类,轻链为kappa链。利用大肠杆菌原核表达系统,表达一系列截短的g B蛋白,最终确定1E7识别的抗原表位是~(81)SAEESLE~(87)。序列分析和western blot结果表明该表位在各PRV病毒株间相对保守。该MAb的制备为建立具有广泛适用性检测PRV野毒感染和疫苗免疫效果评价的阻断ELISA方法奠定了基础。     

ELISA在猪伪狂犬病诊断中的应用

近年来 ,猪伪狂犬病不断传播蔓延 ,给世界养猪业带来了巨大危害 ,因此开发特异性强、敏感性高、简便、快速、能区别疫苗毒和野毒、能检出潜伏感染的诊断方法是防制该病的关键之一。EL ISA方法具有特异、敏感、快速、稳定等特点 ,为广大兽医工作者所关注。目前 ,国内外关于 EL ISA在猪伪狂犬病诊断中的应用方面的研究已有不少 ,已有试剂盒出售。笔者综述了应用于猪伪狂犬病诊断的多种 EL ISA方法 ,如直接 EL ISA、间接 EL ISA、竞争 EL ISA、斑点EL ISA、SPA-EL ISA、双抗体夹心 EL ISA、单抗夹心 L AB-EL ISA、血清学鉴别 EL ISA等。这些方法中 ,有测病毒的 ,有测抗体的 ;有单抗介导的 ,有多抗介导的 ;有的还引入了 SPA和 L AB;有的以分子生物学为基础并能够鉴别疫苗毒和野毒。此外 ,还总结了目前所用 EL ISA诊断方法的优点和缺点 ,并预测了其发展前景     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

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.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.