兔出血症病料中病毒核酸成分的分别鉴别

将兔出血症病毒（ＲＨＤＶ）感染死亡兔肝反复冻融，分别经氯仿抽提，聚乙二醇（ＰＥＧ）沉淀浓缩，蔗糖垫底超速离心，Ｓｅｐｈａｒｏｓｅ４Ｂ柱层析及蔗糖密度梯度离心，得到纯化的ＲＨＤＶ。电镜观察，ＲＨＤＶ粒子无囊膜，大小为３２～３４ｎｍ，核要酸展层法显示，病毒基因组核酸长度约为７．０ｋｂ。用苯酚抽提法从上述病毒悬液中提取的核酸，在琼脂糖凝胶电泳呈现２条主带，当以λＤＮＡ－ＨｉｎｄⅢ消化物为分子量标准时，它     

产蛋下降综合征（EDS－76）病毒DNA探针的制备及应用研究

用纯化的产蛋下降综合征（ＥＤＳ－７６）病毒（Ｈ９１毒株）悬液提取的核酸，经琼脂糖凝胶电泳只出现１条分子量较大、背景清晰的核酸带。用ＢａｍＨＩ酶消化产生４个片段，大小分别为１７ｋｂ、１０ｋｂ、４．０ｋｂ和２．０ｋｂ。将其中的２．０ｋｂ片段克隆进ｐＵＣ１８ＤＮＡ载体中，重组质粒ＤＮＡ用ｄｉｇｏｘｉｇｅｎｉｎ标记作为ＤＮＡ探针，在ｄｏｔｂｌｏｔ中该探针不与鹅胚尿囊液核酸抽提物、马立克氏病病毒（ＭＤＶ）ＤＮＡ、鸡传染性贫血病毒（ＣＡＶ）ＤＮＡ、ＳＰＦ鸡基因组ＤＮＡ等核酸反应，只与３株ＥＤＳ病毒（ＥＤＳ标准毒株ＡＶ－１２７、ＥＤＳＨ９１毒株和从健康鹅体中分离的ＥＤＳＹ８１毒株）ＤＮＡ呈阳性反应。人工感染产蛋母鸡和雏鸡后２４ｈ即可用该探针从泄殖腔棉拭子样品中检测出ＥＤＳ病毒ＤＮＡ，在感染后３５ｈ仍能从部分感染鸡样品中检出。对部分探针检测阳性鸡的泄殖腔棉拭子样品用ＳＰＦ鸡胚分离病毒，并用ＨＡ和ＨＩ试验检测分离病毒的特异性；在感染过程中，同时检测了血清中ＨＩ抗体的消长情况。结果表明，人工感染鸡排毒至少可以维持２个月左右，而且血清中ＨＩ抗体即使很高，也不能阻止感染鸡的排毒。     

产蛋下降综合征（EDS—76）病毒DNA探针的制备及应用研究

用纯化的产蛋下降综合征（ＥＤＳ－７６）病毒（Ｈ９１毒株）悬液提取的核酸，经琼脂糖凝胶电泳只出现了１条分子量较大、背景清晰的核酸带。用Ｂａｍ ＨＩ酶消化产生４个片段，大小分别为１７ｋｂ、１０ｋｂ、４．０ｋｂ和２．０ｋｂ。将其中的２．０ｋｂ片段克隆进ｐＵＣ１８ＤＮＡ载体中，重组质粒ＤＮＡ用ｄｉｇｏｘｉｇｅｎｉｎ标记作为ＤＮＡ探针，在ｄｏｔ ｂｌｏｔ中该探针不与鹅胚尿囊液核酸抽提物、马立克氏病病毒（ＭＤ     

应用生物素标记的NDV—cDNA探针检测感染尿囊液中DNV—RNA的初…

本文应用聚合酶链反应（ＰＣＲ）技术从构建的新城疫病毒（ＤＮＶ）ｃＤＮＡ文库中扩增含编码Ｆ糖蛋白前体－Ｆｏ酶切位点序列的３５９ｂｐ的Ｆ蛋白基因ｃＤＮＡ片段。将此３５９ｂｐ ｃＤＮＡ片段经光敏生物素标记后，即成ＤＮＶ－ｃＤＮＡ探针。该探针能特异性地从感染的尿囊液中检测出ＤＮＶ强毒株和疫苗毒株的基因组ＲＮＡ，而不与ＩＢＤＶ－ｄｓＲＮＡ，ＡＩＢＶ－ｓｓＲＮＡ，ＥＤＳ７６－ｄｓＤＮＡ、ＭＤＶ０ｄｓＤＮＡ、Ｆ     

用 Digoxigenin 标记核酸探针检测 EDS-76 病毒核酸的研究

用ＥＤＳ７６病毒标准ＡＶ１２７株和分离株（Ｂ９６株）感染鸭胚，提取病毒核酸，分别经ＥｃｏＲｌ和Ｐｓｔｌ双酶切，获得图形和大小相似的酶切片段。分别进行ＥｃｏＲｌ和Ｐｓｔｌ单酶切，也得到相似结果。病毒ＤＮＡ经ＥｃｏＲｌ和Ｐｓｔｌ双酶切后，与ＰＵＣ１９质粒载体重组，并转化到ＥｃｏｌｉＪＭ１０１中，筛选出一个插入片段（Ｇ片段）约为２７ｋｂ的重组质粒。用Ｄｉｇｏｘｉｇｅｍｉｎ标记ＥＤＳ７６ＤＮＡＧ片段（ＥｃｏＲｌ和Ｐｓｔｌ双酶切片段）及含该片段的重组质粒分别制备探针，对ＥＤＳ７６病毒ＤＮＡ进行斑点杂交，两种探针均为阳性，而对照组ＮＤＶ、ＩＢＶ、ＩＬＴＶ、ＩＢＤＶ正常鸭胚尿囊液的核酸为阴性。且后一种探针的敏感性高于前者，它的ＤＮＡ检出限量为４ｐｇ水平。结果表明，两种探针具有高度的特异性、敏感性。     

麻雀体内传染性法氏囊病病毒的分离鉴定及理化特性研究

从传染性法氏囊病（ＩＢＤ）阳性麻雀体内分离到了一株病毒，用传染性法氏囊病病毒（ＩＢＤＶ）单克隆抗体心ＥＬＩＳＡ试验和ＤＩＧ－标记ＩＢＤＶｃＤＮＡ探针班点杂交试验证明该病毒为ＩＢＤＶ。病毒可适应于鸡胚和鸡胚成纤维细胞，产生细胞病变效应（ＣＰＥ）。病毒血清型为Ｉ型，病毒代谢抑制试验证明其基因组为ＲＮＡ，病毒核酸的电泳图谱呈两条特征带。病毒对乙醚不敏感ＰＨ２．０不能灭活可使病毒失感染性，５６℃作用３小时     

用PCR技术从同一兔出血症病料扩增和检出2种病毒核酸

应用 Ｐ Ｃ Ｒ 和 Ｒ Ｔ Ｐ Ｃ Ｒ 技术，对兔出血症病毒核酸作了鉴定。分别设计合成 ２ 对 Ｐ Ｃ Ｒ 扩增特异性引物，即按兔出血症病毒中国分离的 Ｎ Ｊ株核酸序列合成 １ 对引物（ Ｎ Ｊ引物），按德国分离的 Ｆ Ｒ Ｇ 株核酸序列合成另 １ 对引物（ Ｆ Ｒ Ｇ 引物），进行 Ｐ Ｃ Ｒ 和 Ｒ Ｔ Ｐ Ｃ Ｒ。从纯化的病毒核酸样品和感染 Ｄ Ｊ Ｒ Ｋ 细胞的病毒核酸样品中，均扩增出 ２ 对引物范围内的特异性核酸片段， Ｎ Ｊ引物扩增产物为 ３６４ ｂｐ， Ｆ Ｒ Ｇ 引物扩增产物为 ５１３ｂｐ。模板用 Ｒ Ｎａｓｅ 消化后，仍出现 ３６４ ｂｐ 带，用 Ｄ Ｎａｓｅ Ｓ１ 消化，则此带消失；反之，用 Ｄ Ｎａｓｅ Ｓ１ 消化，出现５１３ ｂｐ 带，用 Ｒ Ｎａｓｅ 消化，则此带消失，证实前者模板为 Ｄ Ｎ Ａ，后者为 Ｒ Ｎ Ａ。 Ｓｏｕｔｈｅｒｎ 杂交试验证实， Ｐ Ｃ Ｒ扩增出的核酸片段与各自的地高辛标记特异性探针发生强阳性杂交反应。由此认为，在兔出血症病毒感染中，同时存在着 ２ 种不同核酸型的病毒。     

用地高辛标记的核酸探针从尿囊液和组织中检测传染性支气 …

将ＩＢＶＴ株基因组Ｓ１基因上０．６kb片段（位于Ｓ１基因上１１２１bp～１７２３bp之间）克隆到ＰＩＢ－ＰＣＲ Ｃloning vector中,用地高辛标记探针,分别与９株ＩＢＶ 的ＰＣＲ产物和１２株ＩＢＶ的核酸进行点杂交均呈阳性反应,而该探针不与ＩＢＤＶ和ＮＤＶ的ＲＮＡ,ＥＤＳ－７６病毒的ＤＮＡ及正常鸡胚尿囊液的抽提物反应。探针检测ＩＢＶ－ＰＣＲ产物的灵敏度为１００～２００pg。用该探针检测不同毒株ＩＢＶ在鸡胚中的繁     

禽传染性支气管炎病毒免疫原基因组的RT—PCR研究

本文报道了用聚合酶链反应获取ＩＢＶ Ｍ４１株和广东肾变栋Ｄ４１免疫基因的研究情况，所用引物为ＩＢＶ Ｂｅａｕｄｅｔｔｅ株Ｓ１基因两侧的对应序列，跨幅为１．７ｋｂ；ＤＮＡ模板为ＩＢＶＭ４１和Ｄ４１株经病毒ＲＮＡ提取后反转录而得；２株病毒所获的ＰＣＲ产物与预期一致。     

牛传染性鼻气管炎病毒tk基因的克隆

根据牛传染性鼻气管炎病毒ＬＡ株的物理图谱及Ｃｏｐｅｒ株和ＬＡ标ｔｋ基因在基因组中的定位，将ＬＡ株ＤＮＡ ＨｉｎｄⅢＡ片段中的ＳａｌＩ－ＳａｌＩ亚片段、ＢｇｌⅢ－ＳａｌＩ双酶切亚片段分别克隆到载体质粒ｐＢｌｕｅｓｃｒｉｐｔＳＫ中，筛选出３个重组质粒ｐ＾ｔｋ－１，Ｐｔｋ－２和Ｐｔｋ－３，其外源片段大小分别为２．７ｋｂ，１．１ｋｂ和１．６ｋｂ。经酶切分析及同源核酸探针杂交试验表明，２．７ｋｂ ＳａｌＩ－     

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.