不同养殖模式下山羊隐孢子虫感染分析及基因型鉴定

为探讨四川部分地区不同养殖模式下成年山羊隐孢子虫的感染差异以及感染虫种基因型,分别采集了规模化养殖模式和散养模式各6个养殖场共342份新鲜粪便,采用改良饱和蔗糖溶液漂浮法处理后提取粪便DNA,经套式PCR扩增18S rRNA基因,产物测序后进行遗传进化分析。结果:采样地区山羊隐孢子虫总感染率为4.7%,12个养殖场中4个养殖场(名山、纳溪、邻水和双流)存在隐孢子虫感染,感染率2.5%～19.2%,且4个隐孢子虫感染阳性场均为散养模式。序列分析表明,感染虫种为肖氏隐孢子虫(Cryptosporidium xiaoi)和猪隐孢子虫(C.suis),并以肖氏隐孢子虫为主(68.7%)。本试验初步表明,规模化养殖模式和散养模式下山羊隐孢子虫感染存在差异(P0.01);首次在成年山羊中检出猪隐孢子虫虫种,序列分析表明所获得的猪隐孢子虫序列与人源猪隐孢子虫序列完全一致,提示此次分离的羊源猪隐孢子虫为人兽共患隐孢子虫种。     

山东部分地区猪源隐孢子虫卵囊的分离与基因型鉴定

应用抗酸染色技术对山东地区部分猪场隐孢子虫感染情况进行检测,通过PCR扩增部分18s r RNA序列,分析同源性,并绘制基因进化树,鉴定其基因型。结果表明,648份猪粪样品的感染率为12.04%,隐孢子虫卵囊有两种形态,18s r RNA序列分析发现与C.parvum"mouse"型和C.muris有100%和99.8%的同源性,并分别处于同一分支。说明山东地区猪隐孢子虫感染率较高,感染的隐孢子虫基因型是C.parvum"mouse"型和C.muris,提示猪与鼠之间存在交叉传播的可能。     

河南省鸵鸟隐孢子虫流行病学调查

为了系统掌握河南地区鸵鸟隐孢子虫流行状况,于2006年8月～2007年8月对河南地区6个养殖场共829份样品应用饱和蔗糖溶液漂浮法和改良抗酸染色法进行感染情况调查,结果显示隐孢子虫总感染率为1.7%(14/829),其中,郑州某驼鸟场的感染率2.8%(14/506),其他养殖场未发现隐孢子虫感染.所查到的14份隐孢子虫阳性样品来自20～40日龄鸵鸟,表明幼龄鸵鸟更容易感染隐孢子虫.鸵鸟隐孢子虫卵囊大小为4.2～6.0 μm×4.5～5.0 μm,平均5.56 μm×4.48 μm,卵囊形状指数(L/W )为1.24(n=100),根据卵囊形态结构特征初步鉴定为贝氏隐孢子虫(Cryptosporidium baileyi).     

保定地区奶牛源隐孢子虫的分离与基因鉴定

为了解保定地区奶牛源隐孢子虫感染情况,从当地3个奶牛场随机采集145份奶牛粪便经饱和蔗糖溶液漂浮后直接镜检和抗酸染色后镜检,阳性样品采用PCR方法扩增18S rRNA基因,同时将扩增出的目的片段进行克隆和序列分析,并将分离株与其他11个隐孢子虫参考株的18S rRNA序列进行比对和遗传距离比较。结果表明:有10份粪便样本为隐孢子虫阳性,感染率为6.9%(10/145),不同奶牛场、年龄段奶牛隐孢子虫感染率有显著性差异(P0.05)。10份粪便样品采用PCR方法扩增后有7份为18S rRNA基因阳性,扩增出的18S rRNA部分基因片段长528 bp。保定地区隐孢子虫分离株扩增的基因序列与牛源隐孢子虫18S rRNA基因序列(Gen Bank登录号为HQ179571)同源性最高,确定保定地区分离到的奶牛源隐孢子虫为牛隐孢子虫。     

微小隐孢子虫子孢子表面抗原CP15基因的克隆及核苷酸序列分析

目的对编码微小隐孢子虫(Cryptosporidium parvum)子孢子表面抗原CP15基因进行克隆和序列分析,并对其编码的氨基酸变异情况进行分析。方法对田间分离的鼠、兔、猪源微小隐孢子虫提取总RNA,经RT-PCR扩增CP15基因,克隆到pMD 18-T载体中,鉴定正确后进行序列测定,并与GenBank上下载的序列进行同源性比对。结果克隆的CP15基因核苷酸序列与GenBank登录的核苷酸序列比较,鼠源微小隐孢子虫同源性为99.23%,兔源微小隐孢子虫为97.96%,猪源微小隐孢子虫为98.72%,氨基酸序列同源性分别为100%、97.7%和98.4%。结论获得微小隐孢子虫子孢子表面抗原CP15基因,不同宿主来源的CP15基因序列高度一致,为利用该基因进行免疫预防和诊断研究奠定了基础。     

西北部分地区藏香猪隐孢子虫感染情况研究

为了解我国西北部分地区藏香猪隐孢子虫的感染和种类分布,从陕西省和青海省采集了共450份藏香猪新鲜粪便样品,基于隐孢子虫18S rRNA基因的分子生物学方法对粪便样品中隐孢子虫感染情况及其种类进行了研究。结果显示,藏香猪隐孢子虫总感染率为14.2%,青海省藏香猪的感染率(23.9%)显著高于陕西省(3.7%)(P0.01);不同年龄段藏香猪隐孢子虫感染率差异显著(P0.01),其中断奶后仔猪感染率(42.9%)最高,而哺乳仔猪和成年猪均未检测到隐孢子虫的感染;序列分析发现,藏香猪的隐孢子虫均为Cryptosporidium scrofarum。研究结果为藏香猪隐孢子虫病的防控提供了基础数据。     

猴源人隐孢子虫的分离与鉴定

为了解感染不同灵长类动物的隐孢子虫种类以及与感染人的人隐孢子虫(C.hominis)之间的遗传差异,本研究采用形态学和分子生物学方法对猴源隐孢子虫进行分离和鉴定。利用常规方法分离猴粪便中的隐孢子虫卵囊,通过改良抗酸染色和荧光显微镜观察对其进行形态学鉴定;并采用PCR方法扩增其卵囊壁蛋白(COWP)基因和18SrRNA基因,扩增产物克隆至pMD-18-T载体中,对阳性克隆进行测序并作进化树分析。结果表明:抗酸染色和荧光检查结果与所报道的人隐孢子虫的结果一致。PCR扩增产物经电泳检测,明显地出现554bp和370bp大小的片段,与预期结果一致;两种基因的序列分析结果显示该猴源隐孢子虫与C.hominis的相似性均为100%。由此可认为本次分离的隐孢子虫为C.hominis。     

猪源隐孢子虫Hsp70基因的测定与种系发育关系分析

从河南两个地区猪的粪便中分离纯化了猪源隐孢子虫卵囊。参考隐孢子虫Hsp70基因属特异性引物,用PCR分别扩增了卵囊基因组DNA大小均为1 948 bp的片段,PCR产物经电泳鉴定后用试剂盒回收纯化,纯化后PCR产物直接测序。将测得的序列和推测出的氨基酸序列分别用ClustalX软件与已报道的相应序列比对,用DNASTAR中的MegAlign分析其同源性,并用PAUP绘制系统发育进化树。序列分析结果显示河南猪源隐孢子虫两个分离株Hsp70 DNA序列的同源性为99.9%,与其他隐孢子虫相应序列同源性介于81.9%~99.8%之间,其中与猪隐孢子虫(Cryptosporidium suis,AF221533)同源性最高分别为99.8%,97.9%;与安氏隐孢子虫(C.andersoni,AY954592)同源性最低。两个分离株推导Hsp70氨基酸序列的同源性为100%,同其他隐孢子虫相关序列的同源性在92.8%~99.8%之间。本研究为隐孢子虫诊断及流行病学研究打下了良好基础。     

隐孢子虫不同基因型P23基因的克隆及序列比较

为克隆隐孢子虫不同基因型子孢子表面抗原P23基因,比较其序列差异,提取上海地区分离的隐孢子虫鼠基因型(Cryptosporidiummouse genotype)、隐孢子虫兔基因型(Cryptosporidiumrabbit geno-type)、隐孢子虫猪基因型Ⅱ(Cryptosporidiumpig genotypeⅡ)总RNA,经RT-PCR扩增P23基因,克隆到pMD18-T载体中,进行序列测定,并与GenBank上下载的微小隐孢子虫(Cryptosporidium parvum)序列进行同源性比对。结果显示,从隐孢子虫3个基因型中均扩增出了P23基因。与微小隐孢子虫P23基因核苷酸序列比较,隐孢子虫鼠基因型、兔基因型、猪基因型ⅡP23基因同源性分别为97.6%、97.3%、97.3%,氨基酸序列同源性分别为97.3%、97.3%和96.4%。获得了隐孢子虫鼠基因型、兔基因型、猪基因型Ⅱ子孢子表面抗原P23基因。     

印度西孟加拉奶牛隐孢子虫人畜共患传播的分子特性及评估

过去很少开展印度奶牛隐孢子虫遗传多样性和在人畜共患潜力方面的研究。为了评估奶牛作为人感染隐孢子虫传染源的重要性,从印度西孟加拉2个奶牛场采集180头奶牛和50位养殖工人的粪样,用PCR方法扩增隐孢子虫DNA序列,通过PCR-RFLP分析进行隐孢子虫18S rRNA基因分型。对本试验扩增的DNA序列和GenBank公布的相关序列进行系统发育分析。青年奶牛的隐孢子虫感染率高于成年奶牛的感染率,总感染率为11.7%。微细隐孢子虫、牛隐孢子虫等在牛上的发生率呈年龄相关。在1份小牛样品中检测到了猪隐孢子虫基因型DNA。养殖场工人感染了人隐孢子虫、微细隐孢子虫和新型牛隐孢子虫。试验结果表明,印度奶牛场存在人和奶牛之间传播隐孢子虫的潜在风险。     

Comparison of in vitro and in situ methods in evaluation of forage digestibility in ruminants

The objective of this study was to compare the application of different in vitro and in situ methods in empirical and mechanistic predictions of in vivo OM digestibility (OMD) and their associations to near-infrared reflectance spectroscopy spectra for a variety of forages. Apparent in vivo OMD of silages made from alfalfa (n = 2), corn (n = 9), corn stover (n = 2), grass (n = 11), whole crops of wheat and barley (n = 8) and red clover (n = 7), and fresh alfalfa (n = 1), grass hays (n = 5), and wheat straws (n = 5) had previously been determined in sheep. Concentrations of indigestible NDF (iNDF) in all forage samples were determined by a 288-h ruminal in situ incubation. Gas production of isolated forage NDF was measured by in vitro incubations for 72 h. In vitro pepsin-cellulase OM solubility (OMS) of the forages was determined by a 2-step gravimetric digestion method. Samples were also subjected to a 2-step determination of in vitro OMD based on buffered rumen fluid and pepsin. Further, rumen fluid digestible OM was determined from a single 96-h incubation at 38°C. Digestibility of OM from the in situ and the in vitro incubations was calculated according to published empirical equations, which were either forage specific or general (1 equation for all forages) within method. Indigestible NDF was also used in a mechanistic model to predict OMD. Predictions of OMD were evaluated by residual analysis using the GLM procedure in SAS. In vitro OMS in a general prediction equation of OMD did not display a significant forage-type effect on the residuals (observed - predicted OMD; P = 0.10). Predictions of OMD within forage types were consistent between iNDF and the 2-step in vitro method based on rumen fluid. Root mean square error of OMD was least (0.032) when the prediction was based on a general forage equation of OMS. However, regenerating a simple regression for iNDF by omitting alfalfa and wheat straw reduced the root mean square error of OMD to 0.025. Indigestible NDF in a general forage equation predicted OMD without any bias (P ≥ 0.16), and root mean square error of prediction was smallest among all methods when alfalfa and wheat straw samples were excluded. Our study suggests that compared with the in vitro laboratory methods, iNDF used in forage-specific equations will improve overall predictions of forage in vivo OMD. The in vitro and in situ methods performed equally well in calibrations of iNDF or OMD by near-infrared reflectance spectroscopy.     

大庆市羊东毕吸虫病流行病学调查

对大庆市羊东毕吸虫病的流行病学进行了调查研究。结果表明，大庆有3种东毕吸虫，即程氏东毕吸虫（O.cheni)、土耳其斯坦东毕吸虫（O.turkestanica)和土耳斯坦东毕吸虫结节变种（O.turkestanican var.thuberculata)；中间宿主螺类有1种，即卵萝卜螺；东毕吸虫病在大庆分布很广，所调查的4区2县均有发生，羊东毕吸虫平均感染率分别为50．33％，平均死亡率为21．12％，大庆羊急性病例发病时间为8月上旬至10月下旬，慢性病例为11月上旬至翌年2月中旬。     

Use of cyclocryotherapy in management of glaucoma in dogs

In 5 cases of glaucoma (2 from trauma, 2 from narrowed drainage angles, 1 secondary to lens extraction), cyclocryotherapy was used to control intraocular pressure. In all cases the intraocular pressure decreased, with the usual result being a cosmetic and painless but blind eye.     

中国圈养野生动物疫苗使用调查

2005年对中国动物园协会单位中的18家动物园饲养野生动物疫苗免疫情况进行调查。受调查动物园在野生动物疫苗使用和动物种类方面具有一定的代表性。调查结果显示动物园动物现共使用18类36种疫苗,预防31种疫病。其中哺乳动物使用14类24种疫苗,预防24种疫病;禽类使用4类12种疫苗,预防7种疫病。使用范围最广的有禽流感、犬瘟热疫苗等、新城疫疫苗、猫瘟热疫苗等。共有24目58科动物接种疫苗,其中食肉动物类1目8科,食草动物类3目9科,杂食动物类2目3科,禽类18目38科。研究结果提示应加强动物园之间疫病信息交流、防疫资源的利用、疫病监测和研究,加大对动物园动物疫病的研究投入,逐步建立动物园动物统一的防疫规程。     

Estimate of economic impact of fowl cholera in turkeys in Georgia in 1986

Information gathered from cases of fowl cholera (FC) in commercial turkey flocks through case records, flock records, and telephone and mail surveys was used to estimate disease costs. The cost to the Georgia commercial turkey industry in 1986 from preventive measures, treatment of outbreaks, and production losses from the disease was estimated at $634,545. The cost of FC per kg of live production was estimated to be $0.015.     

ELISA试验在防制猪伪狂犬病中的应用

猪伪狂犬病是由伪狂病病毒(Pseudorabies virus PRV)引起的急性传染病。其特征是成年猪常为隐性感染，可有流产、死胎、呼吸系统症状，新生仔猪除神经症状外还可侵害消化系统，并伴大批死亡。本病已经给全世界的养猪业造成严重的损失，我国许多地区已报道该病。为进一步探讨该病的控制、净化措施，我们对12个养猪场共856分血清采用美国嗍公司的ELISA试剂盒进行了抗体检测。     

Occurrence of MRSA in pigs and in humans involved in pig production--preliminary results of a study in the northwest of Germany

In 2007, 678 pigs of all age groups out of 347 different farms from Lower Saxony and Northrhine-Westphalia and 86 persons occupationally exposed to pigs were investigated for their nasal colonisation with methicillin-resistant Staphylococcus areus (MRSA) by the Field Station for Epidemiology of the University of Veterinary Medicine Hannover and the Robert Koch-Institute. At the individual animal level, a frequency of positive results of 13% (n = 85 positive animals) and at the herd level, a frequency of positive results of 18% (n = 62 positive herds) were found. All isolates were assigned to the Multilocus Sequence Typing Type ST398. Within MRSA-positive herds, there were more MRSA-negative than MRSA-positive animals. Among the occupationally exposed persons (veterinarians, laboratory personnel and meat inspection personnel), 20 persons (23%) showed a nasal colonisation with MRSA ST398. A quite strong association between the intensity of the contact to pigs with the frequency of nasal colonisation in the occupationally exposed persons was detected. None of the animals or the humans nasally colonised by MRSA ST398 showed any clinical symptoms of a staphylococcal infection. Conclusions are drawn on the herd and intra-herd prevalence of the nasal colonisation of pigs with MRSA ST398 in pigs, but especially on which questions need to be addressed by further research.