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 93 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.
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   

7.
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   

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.
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   

10.
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   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
17.
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.  相似文献   

18.
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  相似文献   

19.
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  相似文献   

20.
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