猪囊尾蚴头节单克隆抗体的制备及特性鉴定

为制备抗猪囊尾蚴头节单克隆抗体(MAb),本研究采用纯化的猪囊尾蚴头节(Cysticercus Cellulosae Scolex)作为抗原免疫BALB/c小鼠,通过杂交瘤细胞技术,获得3株分泌抗猪囊尾蚴头节MAb的杂交瘤细胞系(分别命名为2C6、3A5和4G10)。对这3株MAb进行生物学特性鉴定,其染色体平均记数为92±10对,经间接ELISA检测腹水效价分别为1:12800、1:6400和1:25600。亚类鉴定证实,这3株亚类均为IgG1型。Westernblot检测表明,3株纯化的MAb均可与猪囊尾蚴头节抗原发生特异反应;而与猪囊尾蚴囊壁和囊液抗原均不发生反应。本研究获得的3株MAb为猪囊尾蚴病免疫学诊断研究奠定技术基础。     

猪传染性胃肠炎病毒单克隆抗体的制备与鉴定

以纯化的猪传染性胃肠炎病毒(TGEV)作为抗原免疫BALB/c小鼠,经3次免疫后,通过聚乙二醇方法进行融合,利用有限稀释法在HAT培养基上筛选杂交瘤细胞,共获得12株既能稳定生长并可以分泌特异性抗TGEV的单克隆抗体的杂交瘤细胞系,分别命名为8D2、4H4、5D6、7H10、4C3、9G1、3A2、8G1、5G6、2D7、4D6、6B10。间接ELISA、Western blot、间接免疫荧光结果表明,获得的12株单抗能特异性识别TGEV,通过间接ELISA做病原检测,显示12株单抗与猪流行性腹泻病毒(PEDV)和猪轮状病毒(PrV)不发生交叉反应。经抗体亚类鉴定,该12株单克隆抗体均为IgG2b。12株抗TGEV的单抗制备成功,为猪传染性胃肠炎病原特性研究和病原快速检测提供了物质基础。     

兔豆状囊尾蚴囊液蛋白的纯化与抗原性鉴定

为了找出抗原性强、免疫原性好的兔豆状囊尾蚴抗原蛋白,本研究对兔豆状囊尾蚴的头节、体节和囊膜等结构性抗原与囊液中代谢性抗原进行了比较,发现囊液代谢性抗原的免疫效果优于结构性抗原。通过SDS-PAGE和微孔超滤分离法对囊液蛋白进行纯化,再用纯化的蛋白免疫小鼠,制备高免血清,并对免疫鼠的免疫器官进行病理学和免疫组织化学检查。结果证明用从囊液中纯化的63 000蛋白免疫效果最好。用纯化的63 000蛋白免疫小鼠可获得高效价抗血清,小鼠免疫器官活化,巨噬细胞、滤泡树突细胞、淋巴细胞和浆细胞等各种免疫细胞增多,用免疫组织化学染色,免疫器官中的CD4、CD8T细胞和CD20B细胞呈强阳性反应。总之,从囊液中分离纯化的63 000蛋白抗原性强、免疫原性,可用于对豆状囊尾蚴病的免疫学诊断。     

小反刍兽疫病毒核蛋白单克隆抗体的制备与初步应用

针对小反刍兽疫病毒核蛋白制备特异性的单克隆抗体,并对其进行生物学特性鉴定和初步应用。以纯化的Bacmid-PPRV-N重组蛋白为抗原免疫BALB/c小鼠,取免疫小鼠的致敏脾细胞与SP2/0骨髓瘤细胞在PEG作用下融合,获得单克隆抗体,并通过染色体技术等方法研究其生物学特性,将其作为竞争单抗,Bacmid-PPRV-N重组蛋白作为检测抗原建立竞争ELISA检测方法。结果表明:经克隆和间接ELISA筛选,获得了2株能稳定分泌抗小反刍兽疫病毒N蛋白抗体的杂交瘤细胞株,分别命名为5B11和3H10-3B8。生物学特性鉴定试验表明:5B11和3H10-3B8抗体类型和亚类均为IgG2b;5B11单抗腹水的效价达1∶819 200,3H10-3B8达1∶12 800;血清学试验证明2株单抗均能与Bacmid-PPRV-N重组蛋白抗原结合,具有高度的特异性;相加ELISA试验结果显示,5B11和3H10-3B8 2株单克隆抗体分别识别N蛋白上不同的抗原位点;2株杂交瘤细胞的染色体均为99～104。应用建立的c-ELISA检测方法对222份血清样品进行PPRV抗体的检测,与参考试剂盒比较得到98.20%的符合率。本研究获得了2株能稳定分泌抗PPRV N蛋白单克隆抗体的杂交瘤细胞株,以单抗5B11作为竞争抗体建立了PPRV的c-ELISA检测方法。     

三种绦虫蛋白质等电聚焦电泳比较分析

应用PAGE-IEF分析了三种绦虫的可溶性蛋白质。猪囊尾蚴头节囊壁、囊液,细颈囊尾蚴头节囊壁、囊液和曼氏迭宫绦虫成虫蛋白质区带数分别为30、25、29、18和24～29条,主带(峰)数分别为10、9、9、7和12个,面积最大峰分别为J、B、H、F和E峰。五种样品电泳谱在总带数、各pH区带数、主带(峰)数和分布、面积最大峰都明显不同,可供鉴定和鉴别。细颈囊尾蚴蛋白质电泳分析与猪囊尾蚴的比较分析,以及曼氏迭宫绦虫蛋白质电泳分析系国内外首次报道。     

猪肺炎支原体脂蛋白LppB的克隆表达及其编码氨基酸的生物学分析

本研究旨在获得猪肺炎支原体脂蛋白LppB的表达产物,分析其编码氨基酸的生物学特性,为进一步研究脂蛋白LppB的功能奠定基础。试验构建重组表达质粒pET30a-LppB,通过快速定点突变试剂盒将LppB基因中1 068,1 353,1 578nt处的A突变为G,使改造后的LppB基因能在大肠杆菌系统中正确表达,IPTG诱导重组蛋白的表达并进行蛋白纯化。SDS-PAGE分析结果显示,IPTG诱导表达后获得一条特异性蛋白条带,相对分子质量约为70 000,与预期蛋白大小一致。可溶性分析结果表明目的蛋白主要以可溶的形式表达于上清中;Western blot鉴定结果表明纯化的蛋白能与抗6×His标签的单抗发生特异性反应。采用DNAStar Protean模块对脂蛋白LppB进行了二级结构、蛋白质骨架柔性区域、抗原指数的预测,并确定了B细胞抗原优势表位的可能分布。     

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。     

猪囊尾蚴抗原成分及其诊断价值分析

猪囊尾蚴病是一种重要的人畜共患寄生虫病。囊尾蚴病的快速诊断是囊尾蚴病治疗和预防的前提,免疫学诊断方法是近年来的囊尾蚴病临床诊断中的重要辅助手段,高特异性诊断抗原的筛选为近年来的研究热点。囊尾蚴抗原组成复杂,包括囊液抗原、头节抗原、囊壁抗原、循环抗原和排泄分泌抗原等。其中的囊液抗原特异性较好,可用于免疫学诊断,而排泄分泌抗原诊断囊尾蚴的价值尚待进一步研究。     

本地毛形线虫49 Ku ES重组蛋白单克隆抗体的制备与鉴定

采用纯化的本地毛形线虫49KuES重组蛋白免疫BALB/c小鼠,取其脾细胞与SP2/0细胞融合,筛选分泌高滴度McAb的杂交瘤细胞株制备腹水。获得两株稳定分泌抗重组蛋白McAb的杂交瘤细胞株D5和C1。试剂盒鉴定两株McAb均属IgM亚类,其轻链均为K链;间接ELISA检测细胞培养液上清和腹水效价,结果显示,两株细胞培养液上清均达到1∶1.28×10~3,腹水效价均达到1∶1.28×10~4;Westetrn blot结果表明,获得的两株McAb均能特异性的识别约49Ku处的ES抗原;间接ELISA结果显示两株McAb与日本血吸虫成虫、猪囊尾蚴囊液、猪蛔虫、猪鞭虫抗原均无交叉反应,表明两株McAb特异性良好。     

日本脑炎病毒囊膜蛋白单克隆抗体的制备及特性分析

将日本脑炎病毒(JEV)囊膜蛋白Cap-ED3重组蛋白免疫BALB/c雌鼠,应用细胞融合技术制备单克隆抗体,经ELISA筛选获得4株稳定分泌识别JEV ED3蛋白单抗的杂交瘤细胞,命名为1B10、3F5、4H1和5F9。这4株单抗在Western blot和间接免疫荧光试验中均能特异识别JEV NJ2008株。制备4株单抗的小鼠腹水,5F9效价最高,为1∶409 600。空斑减少中和试验结果表明:4株单抗均没有中和活性。相加ELISA试验表明:4株单抗中3F5和4H1识别相同抗原表位,1B10、5F9分别识别其他的抗原表位,且差异较大。应用鸭坦布苏病毒(DTMUV)特异性抗原进行ELISA检测的结果表明:5F9识别的表位与DTMUV有交叉,其他3株识别的抗原表位与DTMUV无交叉。本研究获得了3株JEV囊膜蛋白特异性的单抗和1株识别JEV和DTMUV交叉抗原表位的单抗,为JEV抗原和抗体检测试剂盒的研制提供了良好的物质基础。     

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.     

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.     

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.     

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.     

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.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -