水貂肠炎病毒的提纯及部分生化特性分析

应用高速离心—PEG沉淀—蔗糖和氯化铯密度离心—氯化铯平衡密度梯度离心等方法,从水貂肠炎病毒猫肾细胞培养物中提纯病毒粒子。提纯的病毒粒子分为氯化铯浮密度为1.32～1.36g/ml的空壳病毒粒子和氯化铯浮密度为1.40～1.42g/ml的实心病毒粒子。应用SDS—PAGE分析,实心病毒粒子有结构蛋白3种,(VP_1,VP_2、VP_3),空壳病毒粒子有2种(VP_1、VP_2);从第5d培养物中提纯的实心粒子的VP_3含量少于第7d培养物的量。从第7d培养物中提纯的实心病毒粒子经尿素、NP_(40)、TritonX—100裂解后,在薄层聚丙烯酰胺等电聚焦电泳中出现4条蛋白带。从感染48h的细胞培养物中提取到水貂肠炎病毒线状双股复制型DNA(RF—DNA)。通过琼脂糖凝胶电泳测定,该RF—DNA大约有5000个硷基对。经限制性内切酶分析,RF—DNA有2个HindⅢ酶切点,1个PstⅠ酶切点和1个ECoRⅠ酶切点。     

鸡腹泻轮状病毒核酸电泳型及抗原性的研究

本实验利用聚丙烯酰胺凝胶电泳(PAGE)、酶联免疫吸附试验(ELISA)、琼脂扩散试验(ID)、直接电镜(EM)及免疫电镜(IEM)等方法,在国内首次从腹泻雏鸡粪便及肠内容物中检出禽轮状病毒(AVRV)和非典型轮状病毒(aAVRV)。电镜下发现表面光滑,直径为70nm的完整病毒粒子和表面粗糙、直径约53.5nm的不完整病毒粒子,后者在aAVRV中居多。应用PAGE表明,病毒核酸排列呈现多型性,aAVRV核酸排列为5、2、2、2,AVRV核酸排列不规则。ELISA证实,AVRV与犊牛腹泻轮状病毒(NCDV)和婴儿腹泻轮状病毒有共同抗原性,同属A组;aAVRV与之无共同抗原,结合PAGE结果初步确定为D组。并在MA—104细胞上分离到3株AVRV。     

抗传染性腔上囊病病毒单克隆抗体的特性研究——传染性腔上囊病病毒抗原的培养与提纯

用200－500g/L蔗糖进行不连续梯度离心可除去传染性腔上囊病病毒（IBDV）培养液中的大部分杂蛋白，经检查提纯的IBDV颗粒结构完整、纯度高；经用SDS－PAGE分析表明，IBDV主要结构蛋白带清晰。提示用超滤浓缩法和蔗糖不连续梯度离心提纯的IBDV抗原均可进行其他试验的抗原材料。     

用于ELISA的牛白血病病毒抗原的制备

人工感染牛白血病病毒(BLV)的绵羊血清IgG与溴化氰活化的Sepharose4B偶联,制成免疫吸附柱Ⅰ:用兔抗牛血清IgG与之偶联,制成免疫吸附柱Ⅱ.将BLV粗提抗原经柱Ⅰ和柱Ⅱ亲和层析后获得无色透明抗原。该抗经AGID试验表明具有gp和P抗原活性,回收率分别为38.8％和51.8％;经SDS-PAGE分析表明,含有5种蛋白组分,分子量分别为15、24、64、70和80K道尔顿;经薄层扫描,测得5种组成的百分含量之和为72.08。将提纯抗原同提纯各阶段不同纯度的抗原同时进行ELISA测定,结果以提纯抗原最理想,本底很浅,工作浓度仅为5μg/ml。     

蜜蜂蛹病病毒实验分析报告

应用差速离心和蔗糖密度梯度离心，从死亡的工蜂蛹中提取病毒，经电镜形态鉴定为大约２０ｎｍ直径的球形病毒。病毒核酸型为双链ＲＮＡ，ＳＤＳ－聚丙烯酰胺凝胶电泳测定病毒核酸为６组分，分子量别为０．９４４ｘ１０６、０．８６３ｘ１０６、０．８２５ｘ１０６、０．７５４ｘ１０６、０．７１３ｘ１０６、０．６７５ｘ１０６道尔顿，病毒蛋白外壳为１个组分，分子量为２５．８ｘ１０３道尔顿，沉降系数为５０．８Ｓ。研究结果确定，蜜蜂蛹病病毒（ＢＰＶ）为中国首次发现的一种蜜蜂病毒。     

K_(88)、K_(99)基因工程菌菌毛抗原的提纯及其检测

采用SephadexG－100凝胶过滤和酸盐沉淀两种方法从基因工程菌（GHG001）提纯K88、K99菌毛抗原,经SDS－PAGE测定,所提纯的K88、K99抗原的分子量分别为25000和17000道尔顿.     

犬贾第虫dsRNA病毒的鉴定及特性

对分离到的6株犬贾第虫（Giardia cnais)包囊进行核酸分析，在其中1株犬贾第虫核酸的琼脂糖凝胶电泳图谱上观察到1条长度约7.0kb的片段。经鉴定，该核酸不能被DNA酶（100mg/L）降解，对质量浓度低的RNA酶（0.1mg/L)不敏感，但可被质量浓度高的RNA酶（10mg/L）降解。纯化包囊经流氮冻融后，磷钨酸负染，电镜观察发现有球形、直径约为33nm的病毒样粒子存在，包囊超薄切片在胞质中也观察到该病毒样粒子存在。RNA依赖RNA聚合酶活性测定结果表明，该病毒具有RNA依赖RNA聚合酶的活性。犬贾第虫dsRNA病毒核经RT-PCR扩增后得到1条预计扩增大小的片段，将其回收后连接到pMD18-T载体上进行克隆并测序，所得序列仅与蓝氏贾第虫病毒具有较高同源性。     

鸡传染性支气管炎病毒感染的免疫致病机制

(接第1期) 鸡对IBV的免疫反应 IBV的免疫蛋白 IBV是正链RNA病毒,是冠状病毒科的原型病毒.它有三个结构蛋白,'S'突起糖蛋白位于病毒粒子的表面,由S1和S2两个亚单位构成,分子量分别为92K和84K.膜上的'M'糖蛋白部分露出病毒粒子的表面,分子量的范围为27-36K,核衣壳蛋白位于病毒粒子内部,分子量为52K(Wadey和Westaway,1981;Cavanagh,1983).     

鸡传染性支气管炎病毒感染的免疫致病机制（完）

鸡对IBV的免疫反应IBV的免疫蛋白IBV是正链RNA病毒，是冠状病毒科的原型病毒。它有三个结构蛋白，‘S’突起糖蛋白位于病毒粒子的表面，由S1和S2两个亚单位构成，分子量分别为92K和84K。膜上的‘M’糖蛋白部分露出病毒粒子的表面，分子量的范围为27-36K，核衣壳蛋白位于病毒粒子内部，分子量为52K(Wadey和Westaway，1981；Cavanagh，1983)。     

犊牛腹泻粪样中牛呼肠孤病毒的分离鉴定

通过在培养液中添加胰蛋白酶的方法,用MA104细胞从犊牛腹泻粪样中分离并鉴定了1株能稳定产生细胞病变(CPE)的牛呼肠孤病毒,命名为B-19株.RNA聚丙烯酰胺凝胶(PAGE)电泳可见呼肠孤病毒典型的10条核酸节段,呈3:3:4排列.电镜检测结果显示,病毒粒子呈典型呼肠孤病毒粒子形态,直径约70 nm;病毒L1基因保守区段RT-PCR检测及序列分析表明,扩增出的440 bp 目的片段符合预期大小,而且其核苷酸序列与GenBank参考毒株L1基因序列具有较高同源性;S1基因序列分析表明,B-19株属于呼肠孤病毒血清1型(ST1).     

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.     

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.     

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.     

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 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.