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1.
《畜牧与兽医》2017,(7):88-93
从辽宁某猪场疑似猪繁殖与呼吸综合征(PRRS)病猪全血中分离到1株病毒,经Marc-145细胞5次传代后出现稳定的细胞病变(CPE),电镜观察病毒粒子直径约55 nm,并命名为LNEU12。采用RT-PCR方法扩增分离毒的ORF5全序列,再将目的基因克隆入p MD18-T载体进行测序,并与国内外已发表的毒株序列进行比较。结果表明:分离毒的ORF5基因与LV、Amervac株的核酸同源性分别为87.1%和87.6%,与国内分离的欧洲型毒株同源性为83.5%~94.2%。与LV株比较,分离毒GP5有22个氨基酸发生了变异,并存在3个潜在N-糖基化位点。基因系统发育树分析表明:分离毒LNEU12与BJEU06-1、NVDC-NM1-2011株的亲缘关系很近,而与VR2332美洲株处于不同的分支,由此推断分离毒LNEU12为欧洲型PRRSV。  相似文献   

2.
前期我们实验室分离鉴定了一株nsP2蛋白缺失49个氨基酸(aa)的猪繁殖与呼吸综合征病毒(PRRSV)GXNN1396株。为了进一步对该毒株全基因组序列特性进行分析,将GXNN1396株病毒在Marc-145细胞上传至第3代,收集细胞上清,抽提该病毒RNA。用RT-PCR检测方法对GXNN1396基因组进行分段扩增、克隆、序列比较和遗传进化分析。结果表明,GXNN1 396全长15 263核苷酸(nt),不包括5′帽子结构和3′Poly A尾。其中,5′非翻译区(5′UTR)长为189nt,3′UTR长151nt,ORF1a、ORF1b、ORF2、ORF3、ORF4、ORF5、ORF6、ORF7分别为7 422、4 382、771、765、537、603、525nt和372nt。与国内外的PRRSV毒株核苷酸序列的同源性进行了比较显示,GXNN1396与欧洲经典毒株LV和VR2332株的同源性分别为61%和88.8%,与TJ、JXwn06、JXA1在全基因上的同源性高达97.2%~97.3%,说明GXNN1396株是一株典型的美洲型PRRSV毒株。遗传进化分析表明美洲型PRRSV主要分为3个亚群,GXNN1396与高致病性PRRSV毒株属于同一分支。  相似文献   

3.
用RT-PCR方法从某猪场病猪体内分离到1株猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PRRSV),命名为PRRSV GD-ZQ株,可致Marc-145细胞病变。细胞分离培育病毒至增殖性能稳定后,分别扩增分离病毒的Nsp2、ORF3、ORF5基因并测序,绘制进化树比较分析遗传进化。结果显示分离毒株的Nsp2、ORF3、ORF5基因序列与美洲型VR-2332、CH-1a等毒株核苷酸序列相似性在89.0%~95.8%之间,与欧洲毒株LV的相似性在48.2%~49.3%之间,遗传进化分析显示该毒株与CH-1a株处于同一分支,分离毒株的Nsp2序列与以HEB1为代表的PRRSV变异株相似性在98.3%~99.4%之间。该病毒在细胞盲传5代能产生稳定规律细胞病变(CPE),且第5代病毒TCID50达10-5.6／0.1 mL。进化分析结果显示GD-ZQ分离株是PRRSV变异株,具有"高热病"PRRSV毒株的变异特点,为了解PRRSV在时间上和分子水平上的遗传变异规律、变异幅度和变异范围奠定基础。  相似文献   

4.
为了解广西地区猪繁殖与呼吸综合征病毒(PRRSV)流行毒株的遗传进化情况,对2014年-2016年来自广西各地的部分PRRSV阳性病料进行Nsp2和ORF5基因的扩增和测序分析.结果获得34个Nsp2基因序列和45个ORF5基因序列,均属于美洲型毒株.Nsp2基因间核苷酸序列的同源性为91.8％~100％,与PRRSV美洲型毒株VR-2332、CH-1a、JXA1及NADC30株核苷酸序列的同源性分别为81.3％~84.3％、88.9％~92.1％、94.3％~99.3％和73.5％~75.1％,而与PRRSV欧洲型毒株LV株核苷酸序列的同源性为51.5％~53.2％.ORF5基因间核苷酸序列的同源性为82.8％~100％,与PRRSV美洲型毒株VR-2332、CH-1a、JXA1及NADC30株核苷酸序列的同源性分别为83.7％~99.5％、85％~95％、83.8％~99.7％和83.2％~86.4％,而与PRRSV欧洲型毒株LV株核苷酸序列的同源性为62.4％~64.5％.基于Nsp2和ORF5基因推导的氨基酸序列绘制的遗传进化树中,广西地区的毒株主要分布在以JXA1为代表的Ⅳ亚群.表明当前广西PRRSV流行毒株以JXA1株为代表的高致病性美洲型毒株为主,各毒株Nsp2和ORF5基因序列存在一定的差异,尚未发现欧洲型毒株和美洲型NADC30类毒株.  相似文献   

5.
为了解福建地区猪繁殖与呼吸综合征病毒(PRRSV)流行毒株的分子生物学特性与变异规律,收集了福建省不同地区的12株PRRSV,并对其ORF7基因进行遗传变异分析。结果表明,福建地区存在欧洲型PRRS和美洲型PRRS,10株为美洲型PRRSV,与VR-2332、JXA1等美洲型参考毒株的氨基酸的同源性为89.5%~100%,与欧洲代表毒株LV的氨基酸的同源性分别为59.5%~63.6%。而FJ-11、FJ-12 2株分离株为欧洲型PRRSV,与欧洲代表毒株LV的氨基酸的同源性分别为91.4%、92.2%,而与VR-2332、CH-1a等美洲参考毒株的氨基酸的同源性为60.3%~64.5%。美洲型PRRSV ORF7编码N蛋白氨基酸虽然发生了变异,但相对保守。  相似文献   

6.
采集菏泽地区某猪场PRRS疑似病料,在Marc-145细胞上进行病毒分离,得到一株病毒HZ0622,通过免疫荧光试验初步鉴定分离病毒为PRRSV。对ORF5基因进行克隆和测序,并利用DNAStar软件将测定序列与国内外代表性毒株进行同源性比较,结果表明：分离株HZ0622 ORF5基因与美洲型代表毒株VR-2332的同源性为89.55%,与LV株同源性为61.17%,与中国高致病性PRRSV毒株JXA1、HEB1、SY0608、SD-4的同源性分别为98.84%、98.34%、99.00%、99.34%;进化树分析结果表明,分离株HZ0622和高致病性PRRSV在同一进化分支,且与2007年分离的SD-4有更近的亲缘关系。HZ0622分离株属于美洲型毒株,可能属于高致病性PRRSV。  相似文献   

7.
为研究江西地区猪繁殖与呼吸综合征病毒(PRRSV) ORF5基因的变异情况及NSP2基因的结构特征,采用RT-PCR方法扩增了12份江西地区猪场疑似患PRRS的猪肺脏样品中的ORF5全序列和NSP2部分序列,应用DNAStar和Mega 6.0等软件对所得序列进行同源性比对及遗传变异分析。12株PRRSV ORF5核苷酸同源性为83.7%~99.8%,氨基酸同源性为82.1%~99.5%;与参考毒株JXA1、VR-2332和LV的核苷酸同源性分别为84.9%~99.7%、85.2%~91.0%和62.4%~64.8%。对阳性病料进行了NSP2基因部分序列的扩增,测序结果显示12株PRRSV均属于美洲型毒株,12株PRRSV的NSP2部分序列均存在30个氨基酸的不连续缺失,与高致病性PRRSV有相同的缺失特征。12株PRRSV的ORF5遗传进化树分析显示,10株与高致病性PRRSV处在同一进化分支,进一步说明高致病性PRRSV已成为江西地区的优势流行毒株。  相似文献   

8.
李冰  卢赫  冯方周  丁壮 《中国畜牧兽医》2014,41(12):102-108
试验旨在研究杂交野猪猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus, PRRSV) 辽宁分离株的遗传变异情况及分子生物学特征.用Marc-145细胞从辽宁某杂交野猪场疑似猪繁殖与呼吸综合征(porcine reproductive and respiratory syndrome, PRRS)病猪血液中分离到1株病毒,该分离毒株经Marc-145细胞6次传代后出现稳定的细胞病变,采用RT-PCR方法对分离病毒进行ORF6和ORF7基因的扩增、克隆和测序,并与已知序列毒株的相应片段进行同源性比对.结果表明,分离毒株的ORF6、ORF7基因与国内外美洲型毒株的核苷酸同源性分别为96.0%～100.0%、94.5%～99.4%;氨基酸同源性分别为89.6%～100.0%、87.3%～98.7%;与欧洲型代表毒株LV的ORF6、ORF7基因差异较大,核苷酸同源性分别为70.4%、70.1%,氨基酸同源性分别为48.8%、49.7%.推测辽宁杂交野猪体内分离毒株在基因型上属于美洲型毒株.  相似文献   

9.
为研究江西地区猪繁殖与呼吸综合征病毒(PRRSV)ORF5基因的变异情况及NSP2基因的结构特征,采用RT-PCR方法扩增了12份江西地区猪场疑似患PRRS的猪肺脏样品中的ORF5全序列和NSP2部分序列,应用DNAStar和Mega 6.0等软件对所得序列进行同源性比对及遗传变异分析。12株PRRSV ORF5核苷酸同源性为83.7%~99.8%,氨基酸同源性为82.1%~99.5%;与参考毒株JXA1、VR-2332和LV的核苷酸同源性分别为84.9%~99.7%、85.2%~91.0%和62.4%~64.8%。对阳性病料进行了NSP2基因部分序列的扩增,测序结果显示12株PRRSV均属于美洲型毒株,12株PRRSV的NSP2部分序列均存在30个氨基酸的不连续缺失,与高致病性PRRSV有相同的缺失特征。12株PRRSV的ORF5遗传进化树分析显示,10株与高致病性PRRSV处在同一进化分支,进一步说明高致病性PRRSV已成为江西地区的优势流行毒株。  相似文献   

10.
根据GenBank公布的猪繁殖与呼吸综合征病毒(PRRSV)ATCC VR-2332株的ORF2-6基因的核苷酸序列,设计合成4对特异性引物,用RT-PCR方法扩增出PRRSV河南地方株(命名为HN-2株)的ORF 2～6片段,克隆到pUC-57T栽体并进行测序.应用DNAStar序列分析软件对分离株的ORF 2～6基因和其推导的氨基酸序列与不同来源的9个PRRSV毒株进行了同源性比较,结果表明:该分离株的ORF 2～6基因与不同来源美洲型毒株之间的同源性分别为89.1%～98.1%和81.4%～96.1%,而与欧洲型毒株之间的同源性仅为46.9%～61.9%和44.2%～45.0%;同时将分离株ORF 2～6基因的推导氨基酸序列与7个美洲型PRRSV毒株进行变异分析比较,证实了该分离株ORF 2-6基因发生了变异.  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.
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   

16.
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   

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.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
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