EQUINE HERPESVIRUSES

The immunological and virological status of 3 foals in respect of equine herpesviruses (EHV) was established and the foals were sequentially infected with EHV2, EHV3 and EHV1. Following experimental infection with EHV2, no clinical signs of disease were observed in any foal. The inoculation of EHV3 into the genital tract resulted in lesions of the mucous membrane and perineal skin that were considered typical of equine coital exanthema. Following intransal inoculation of EHV3 extensive ulceration and pustule formation on the nasal mucosa was observed by day 5 accompanied at day 7 by a profuse, mucopurulent nasal discharge; on day 8 pustular lesions of the skin about the external nares appeared. Signs of disease after inoculation with EHV1 were milder than expected in 2 of the 3 foals. The possibility that recent, prior infection with EHV2 and/or 3 may protect against EHV1 was considered.     

MYCOPLASMAS ISOLATED FROM CATTLE IN AUSTRALIA

Ninety-three mycoplasmas isolated in Australia from various pathological conditions in cattle and from healthy cattle were classified using the growth inhibition reaction. Eighty strains were placed in seven of the eight groups described by Leach (1967). The number of additional groups into which the 13 remaining strains may fall is not known. Cross-reactions not described previously were found between M. bovigenitalium and strains of group 7 (L2917).     

EQUINE HERPESVIRUSES: ON THE DIFFERENTIATION OF RESPIRATORY FROM FOETAL STRAINS OF TYPE 1

SUMMARY Confirmation of the occurrence of equine herpesvirus type 1 (EHV1) abortion in both epizootic and sporadic form epizootic in Australia for the first time in 1977 against a background in which a reasonably diligent search for such viruses during the preceeding 11 years failed to associate EHV1 with abortion, provided a special opportunity to compare the properties of the newly isolated foetal (F) strains with a collection of endemic respiratory (R) strains that had been recovered at fairly regular intervals since 1967. Using plaque size and host cell range all of 7 R strains tested were clearly distinguishable from 7 of 11 F isolates. The remaining 4 F strains had plaque diameters of R strains but 3 of the 4 viruses conformed in their host cell range with F strains. Only one F isolate (from Tasmania) had both plaque morphology and host cell range of R strain viruses. The mean diameter of plaques produced by R strains in equine foetal kidney (EFK) cells after 4 days under a methyl cellulose overlay was 1.52 mm (range 1.30–1.84 mm) while the mean diameter of small plaques produced by F strains was 0.82 mm (range 0.68–0.91 mm). In addition to EFK cells all R and F strains grew in an equine dermal (EDerm) cell line and all but two of 19 isolates grew in a pig kidney (PK) cell line. None of the low passage R strains grew in bovine embryo tracheal (EBTr) or feline embryo (FEmb) cells whereas all but one of 11 F isolates grew in EBTr cells. 8/11F isolates also grew in FEmb cell line. Growth of viruses at 33° and 40.5°cf. a usual growth temperature of 37° was of no detectable value in differentiating R and F strains of EHV1. In a limited geographic and time frame the criteria of plaque size in EFK cells and growth in EBTr cells unambiguously distinguished between R and F isolates and represent simple markers worthy of additional study.     

AVIAN ADENOVIRUSES ISOLATED FROM POULTRY IN QUEENSLAND

Adenoviruses isolated from Queensland poultry flocks with respiratory disease and/or egg production problems have been serotyped by comparison with Japanese and Irish types. Two serological types were recognized among 14 isolates examined; 4 were type 112 (Celo type) and the remaining 10 type 506. Isolates B1363 and B4015 were further characterized by immunodiffusion. Both isolates were shown to contain the avian adenovirus group antigen and B1363 also shared a second (type) antigen with Celo (Phelps) strain. Immuno-electron microscopy revealed the presence of adenovirus group antigen and freedom from contamination with other viruses.     

4株鸽源沙门氏菌致病性观察

为了解分离自四川地区的鸽源沙门氏菌的致病性,本研究先将分离的4株沙门氏菌,腹腔注射SPF昆明鼠,测定其半数致死量(LD50),再依据小鼠攻毒试验结果,选取致病性较强的纽波特沙门氏菌菌株,通过灌胃方式接种信鸽来观察对信鸽的致病性.结果显示:甲型副伤寒沙门氏菌、纽波特沙门氏菌、伯里沙门氏菌、基桑加尼沙门氏菌的LD50分别为3.37×10^6、2.49×10^7、5.46×10^7、3.58×107 CFU;感染鼠的肝脏、脾脏、肾脏及小肠有明显的炎性病变;纽波特沙门氏菌可造成感染鸽的肝脏、肺脏、肾脏和胰腺纤维素样变性及炎性细胞浸润等病变,回肠、空肠、盲肠的肠绒毛结构不完整、绒毛上皮脱落,绒毛及肌层有不同程度的炎性细胞浸润.以上结果表明,4株分离的沙门氏菌对试验鼠有一定的致病性,纽波特沙门氏菌可造成信鸽气囊等组织器官损伤,继而影响其飞行能力.本研究为鸽源沙门氏菌尤其是纽波特沙门氏菌的致病性研究提供一定的理论参考,具有公共卫生学意义.     

一株鹅细小病毒全基因特征分析

根据GenBank登录的鹅细小病毒基因序列和基因组结构特征,采用PCR技术扩增获得一株鹅细小病毒株（Goose parvovirus,GoPV）全基因序列,为中国大陆地区首次报道。GoPV株病毒全基因大小为5106nt,其基因组5’端和3’端均含有相同的末端倒置重复序列（inverted terminal repeats, ITR）,ITR全长为444nt。GoPV基因组主要由左右两侧两个开放阅读框组成,左侧编码非结构蛋白（non-structureprotein,NS）NSl和NS2,右侧编码3种结构蛋白（viral structural protein,VP）VP1、VP2和VP3。NS基因全长为1884nt（537-2420nt）,其中NS2全长1356nt（1065～2420nt）;VP基因全长2199nt（2439-4637nt）,其中Ⅵ叼全长1764nt（2874-4637nt）,VP3全长1605nt（3033-4637nt）,在其右侧的ITR前有一个Poly（A）的尾。GoPV株病毒全基因和欧洲疫苗株（EU583392（VG32／1,Europe））核苷酸同源性最高,高达98．6％。本研究为进一步研究GPV分类地位以及进化关系提供依据,也为研究GPV强毒株和疫苗株之间生物学特性以及GPV治病机理和开发基因工程疫苗奠定基础。     

STUDIES ON POXVIRUS ISOLATED FROM A MAGPIE IN QUEENSLAND

An avian poxvirus was isolated from a black-backed magpie in Queensland. The virus produced pocks on the chorio-allantoic membrane of chicken embryos and lesions on the skin of chickens. Comparison by passive haemagglutination test and neutralisation test indicated that the virus was related more closely to pigeonpox virus than to fowlpox virus.     

猪囊尾蚴总RNA的提取与mRNA的分离

目的为比较对猪囊尾蚴总RNA提取与mRNA分离方法的优点。方法采用Promega公司的SV总RNA分离体系、RNAgents总RNA分离体系和hioDev—Tech的TRIZOL LS试剂,对猪囊尾蚴总RNA进行了提取;用Promega的PolyA Ttract mRNA分离体系和Amersharn的Quickprep微量mRNA纯化试剂盒对mRNA进行分离。结果表明经改良的TRIZOLLS试剂,提取猪囊尾蚴RNA效果好,而PolyA Ttract mRNA分离体系分离的mRNA含量高,纯度好。结论所分离的mRNA适合于构建cDNA表达文库。     

从鸭腹水综合征病鸭体内分离鉴定到血清1型鸭肝炎病毒

2011年4月份,河北省某地一些鸭场饲养的20～45日龄的樱桃谷肉鸭发生了以腹腔中充满大量清亮、茶色或啤酒样腹水为主要病变特征的疾病,即鸭腹水综合征。采集两个不同日龄的病死鸭肝脏样品,接种SPF鸭胚进行病毒分离,获得两个病毒分离物（HB01和HB02）。这两个病毒分离物对鸡、鸭和鹅的红细胞均无血凝活性。RT-PCR或PCR检测表明,HB01和HB02中鸭肝炎病毒检测为阳性,而鸭呼肠孤病毒、鸭圆环病毒、鸭黄病毒等检测均为阴性。将HB02接种5日龄SPF鸭,致死率为40%;对20日龄的鸭不致死。HB02分离物中鸭肝炎病毒的序列分析表明其与鸭肝炎病毒NA株及弱毒疫苗株C80和F64遗传距离较近。根据试验结果,推测鸭肝炎病毒可能是诱发本次鸭腹水综合症的因素之一。     

哺乳类和鸟类动物隐孢子虫交叉感染试验研究

为了明确哺乳类和鸟类宿主隐孢子虫能否交叉感染，分别从鸡、兔、小白鼠、鸭、鹌鹑分离到隐孢子虫进行交叉感染。结果，从鸡分离的隐孢子虫卵囊能感染鸭、鹌鹑、麻雀，而不能感染鸽、大白鼠、小白鼠、兔，从鸭分离的卵囊能感染鸡，从兔、小白鼠分离的卵囊不能感染鸡、鹌鹑，从鹌鹑分离的卵囊不能感染兔、大白鼠、小白鼠和鸡。提示隐孢子虫在宿主纲水平上有宿主特异性。     

鸽圆环病毒福建株全基因组序列分析

运用PCR技术从福建省某地发病信鸽组织中获得鸽圆环病毒（Pigeon circovirus,PICV）福建株（简称fj1株）全基因组序列,并对鸽圆环病毒福建株基因组核苷酸组成、结构及其遗传进行分析。结果表明,所获fj1株全基因大小2037 nt,包含有2个主要的开放阅读框（open reading frame,ORF）：ORF-V1（41～994nt）编码复制相关结构蛋白（the replicated-associated protein,Rep）,ORF-C1（1987～1166nt）编码核衣壳蛋白（the putative capsid protein,Cap）;在V1和C1的5＇端之间存在一个与圆环病毒滚环复制有关的高度保守的环状发夹结构。fj1株与GenBank登录所有鸽圆环病毒核苷酸同源性在84.5%～93.8%之间,与中国浙江鸽圆环病毒分离株zj1和zj2核苷酸同源性分别为88.7%和88.9%。从遗传进化上看,中国3株鸽圆环病毒均处在Cap蛋白起始密码子＂ATG＂分支,但分居不同亚群。     

一株分离自肉雏鸡脑部大肠埃希氏菌的某些生物学特性

对一株分离自以神经紊乱为主症状肉雏鸡脑实质的Ｅ．ｃｏｌｉ（ＬＣＢ）的某些生物学特性进行了研究。包括对ＫＭ小鼠及１ｄ鸡的致病性,血清学特性、抗生素敏感性。菌毛的表达及电镜观察、血凝性、溶血性。     

云南日本血吸虫群体生物学的研究

本文报告了我国云南南涧地区日本血吸虫群体生物学的特性。将捕获的该地区光壳钉螺，经人工逸蚴，尾蚴感染实验家兔和小鼠，其平均虫卵开放前期、成虫回收率，两性虫体体长、性腺发育，血吸虫卵引起宿主肝脏组织的病理变化及幼虫大小和毛蚴感染异地钉螺的发育特点作了观察。并进行了11种同工酶电泳图谱和蛋白质组分的分析。