首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 125 毫秒
1.
用京－１株鸡马立克氏病（ＭＤ）强毒感染１￣１０个家系１日龄的ＢＷＥＬ－ＳＰＦ鸡,观察比较临床症状和剖检病变及病理切片,以此评估该ＢＷＥＬ－ＳＰＦ鸡群每个家系鸡对京－１株ＭＤ强毒的敏感性。结果,１,５,８,９号家系的ＢＷＥＬ－ＳＰＦ鸡对京－１株ＭＤ强毒最敏感;３,４,５,６,１０号家庭系次之,２、７号家系敏感性相对较差。  相似文献   

2.
以脂质体转染技术构建了表达鸡传染性法氏囊病病毒（ＩＢＤＶ）ＶＰ２基因的重组鸡痘病毒ＦＰＶ－ＶＰ２,该病毒性在鸡胚成纤维细胞及鸡体内均能稳定产生子代病毒,经翅皮下５×１０＾５ＰＦＵ／羽免疫１日龄ＳＰＦ鸡,免疫后４周以１００ＬＤ５０／羽ＩＢＤＶ超强毒株Ｇ株攻毒,获得了５／６的保护,但不能有效预防临床发病及法氏囊受损萎缩,实验结果证明了ＶＰ２是ＩＢＤＶ的宿主保护性抗原,提示Ｔ细胞介导的免疫可能在ＩＢＤＶ  相似文献   

3.
从病鸡中分离出肾变型传染性支气管炎强毒株,从中选出免疫原性最佳的毒株ＩＢＶｚｊ９３株,其ＥＩＤ５０≥１０＾－８．７／０．２ｍｌ,研制成单价及与呼吸型、腺胃型传支病毒株相配伍的二价、三价及与ＩＢＤ、ＮＤ、ＥＤＳ等相配伍的二联、三联灭能苗,经对１５４７．７９万羽鸡免疫试验,证明安全、有效。  相似文献   

4.
用传染性喉气管炎（ＩＬＴ）强毒株感染１０个家系１５０日龄ＢＷＥＬ－ＳＰＦ鸡,观察比较临床症状和剖检所见病变;用传染性支气管炎（ＩＢ）强毒株和新城疫（ＮＤ）疫苗株分别接种这１０个家系的鸡胚,收获胚液并测定其毒价,从而评估这三种呼吸道病毒在每个家系鸡或鸡胚上的敏感性。  相似文献   

5.
对鸡新城疫病毒（ＮＤＶ）中等毒力毒株ＣＳ２株、ＮＤⅠ系、Ｒｏｋｉｎ、Ｋｏｍｅｒｏｖ和低毒力ＬａＳｏｔａ株病毒的脑内致病指数（ＩＣＰＩ）、鸡胚的半数感染量（ＥＩＤ５０）等指标进行了测定,结果是ＩＣＰＩ分别为１．２７～１．５２、１．６６～１．７０、１．４６、１．４３和０．２９～０．５;ＥＩＤ５０分别为１０＾７．５、１０＾７．５≥１０＾８．５、１０＾＾７．９和≥１０＾８．５／０．１ｍｌ。用１０倍剂量的ＣＳ２株病毒注射１月龄和１．５月龄ＳＰＥ雏鸡,均安全无不良反应,测定ＣＳ２株病毒保存期,结果在－２０℃保存６年的鸡胚２代（Ｅ２）、鸡胚６代（Ｅ６）、鸡胚１０代（Ｅ１０）毒的ＥＩＤ５０均≥１０＾７．５／０．１ｍｌ。ＮＤＣＳ２株病毒的各项指标均在中等毒力范围内,对鸡胚的半数感染量仍保持原毒（Ⅰ系）的特性,ＩＣＰＩ比原毒有所下  相似文献   

6.
腺胃型鸡传染性支气管炎病毒Hu98株的分离鉴定   总被引：4，自引：0，他引：4  
１９９８年首次从哈尔滨市某鸡场鸡腺胃肿大为特征的病例中分离到ＩＢＶ－Ｈ９８毒株。将该病毒株接种ＳＰＦ鸡胚并传至５代（Ｆ５）,结果接种胚出现规律性死亡和典型胚胎病变特征,ＥＩＤ５０为１０＾－６．４０／０．２ｍＬ。ＩＢＶ－Ｈｕ９８Ｆ５感染ＳＰＦ鸡胚尿囊液经负染电镜观察,可见直径为８０￣１２０ｎｍ、有囊膜和纤突的冠状病毒粒子。用ＩＢＶ－Ｈｕ９８Ｆ５毒株人工感染１日龄ＳＰＦ鸡能引起与自然病例相似的病理组织  相似文献   

7.
用单克隆抗体鉴定猪繁殖与呼吸综合征病毒分离株   总被引：9，自引：0，他引：9  
应用ＰＲＲＳＶ单克隆抗体,采用直接与间接免疫荧光抗体试验对分离获得的ＰＲＲＳＶ６个毒株进行了鉴定,结果所有分离毒株均能被单克隆抗体（ＳＤＯＷ１７、Ａ、Ｂ、Ｃ、Ｄ、Ｅ、Ｆ）所识别,呈现特异荧光,６个分离毒株均能与仅识别美洲型ＰＲＲＳＶ的单克隆抗体Ｆ反应,结果表明６个分离毒株均属于美洲型ＰＲＲＳＶ。利用微量细胞培养对分离毒株ＴＣＩＤ５０测定结果表明,６个分离毒株的ＴＣＩＤ５０分别为１０－７．５／０．１ｍｌ、１０－７．５／０．１ｍｌ、１０－７．５／０．１ｍｌ、１０－７．７５／０．１ｍｌ、１０－７．２５／０．１ｍｌ、１０－６．２５／０．１ｍｌ。病毒感染细胞的超薄切片电镜观察表明,在感染细胞浆内可见典型的ＰＲＲＳＶ病毒粒子,呈球形或椭圆形,直径约为６０ｎｍ左右,可见囊膜。  相似文献   

8.
鸡新城疫病毒V4株的生物学特性研究   总被引：4，自引：1，他引：3  
鸡新城疫病毒Ｖ４株对１日龄雏鸡安全；对１０日龄雏鸡一次饮水或滴鼻免疫，半年内，ＨＩ抗体平均效价为２＾５左右；以１００ＥＩＤ５０Ｆ系标准强毒（毒力为１０＾８．５ＥＩＤ５０／０．１ｍｌ）攻击，保护率１００％。并成功地培育了能在５６℃水浴中处理５小时而血凝效价稳定的耐高温毒株Ｖ４－９２，该毒株在２５℃至少保存５周，血凝效价不降。  相似文献   

9.
新城疫V4株弱毒变种的选育   总被引：1，自引：0，他引：1  
应用有限稀释法通过ＳＰＦ鸡胚传代，从新城疫Ｖ２弱毒中克隆出一个变各，即２０代以后的继代毒，命名为新城疫Ｖ４克隆２０弱毒株，（ＮＤ－Ｖ４Ｃ２０）。毒以１０＾－１－１０＾１３×０．１ｍｌ接种１０日龄ＳＰＦ鸡胚尿囊腔１５０小时内，鸡胚极少死亡。每个滴度５个胚有尿液均可凝集鸡红血球。第１０代和第２０代的每个滴度５个胚有的混合尿液以１０＾－６×０．５ｍｌ一次饮水免疫鸡，即能引起ＨＩ抗体反应，也能抵抗新城疫强  相似文献   

10.
IBD野毒株的培育   总被引：4，自引：0，他引：4  
由国内ＩＢＤ高发地区分离到一株ＩＢＤ野毒,使现地鸡群发病率９６％,死亡率６０％以上,为一株超强毒。将该毒株分离,纯化,经鸡胚及鸡胚成纤维细胞传代,得到一株ＩＢＤ超强毒的细胞适应株,毒价高达２．０×１０＾８ＰＦＵ／ｍｌ以上。回归本动物,经免疫原性试验,致病性试验及返祖试验,证明该毒株免疫原性较好而致病力降低。  相似文献   

11.
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。  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号