Cryptosporidium meleagridis in an Indian ring-necked parrot (Psittacula krameri)

OBJECTIVE: To perform a morphological and genetic characterisation of a Cryptosporidium infection in an Indian ring-necked parrot (Psittacula krameri) and to compare this with C meleagridis from a turkey. DESIGN: Tissue and intestinal sections from an Indian ring-necked parrot were examined microscopically for Cryptosporidium. The organism was also purified from the crop and intestine, the DNA extracted and a portion of the 18S rDNA gene amplified, sequenced and compared with sequence and biological information obtained for C meleagridis from a turkey as well as sequence information for other species of Cryptosporidium. RESULTS: Morphological examination of tissue sections from an Indian ring-necked parrot revealed large numbers of Cryptosporidium oocysts attached to the apical border of enterocytes lining the intestinal tract. Purified Cryptosporidium oocysts measured about 5.1 x 4.5 microns, which conformed morphologically to C meleagridis. The sequence obtained from this isolate was identical to sequence information obtained from a C meleagridis isolate from a turkey. CONCLUSION: Cryptosporidium meleagridis was detected in an Indian ring-necked parrot using morphological and molecular methods. This is the first time that this species of Cryptosporidium has been reported in a non-galliform host and extends the known host range of C meleagridis.     

青海省大通县世居牦牛犊隐孢子虫感染情况调查及虫种鉴定

旨在调查青海省大通县部分地区世居牦牛犊隐孢子虫的感染情况及其虫种类型。在大通县宝库乡和良教乡采集了200份3~5月龄世居牦牛犊粪样进行隐孢子虫检测。所有样品经蔗糖密度梯度离心法纯化处理,采用免疫荧光试验（IFT）方法进行检测,阳性样品再用套式PCR扩增18S rDNA,并进行测序和同源性分析以供虫种鉴定。结果表明：免疫荧光试验（IFT）方法镜检出3份隐孢子虫阳性样品,阳性率为1.5%（3/200）;阳性样品经套式PCR扩增18S rDNA后,有2份隐孢子虫样品呈阳性,扩增产物长度为500 bp,测序后将序列命名为QHDTC201901和QHDTC201902;系统发育分析显示,种类鉴定发现2种隐孢子虫,分别为安氏隐孢子虫（Cryptosporidium andersoni）和牛隐孢子虫（Cryptosporidium bovis）,总感染率为1.0%（2/200）。综上提示,大通县部分地区牦牛犊存在隐孢子虫感染,感染虫种为安氏隐孢子虫和牛隐孢子虫。该调查研究为该地区牛隐孢子虫病的防控提供了临床基本数据。     

火鸡隐孢子虫18S核糖体DNA部分序列测定与系统发育分析

从长春地区鸭的粪便中分离纯化了火鸡隐孢子虫（Cryptosporidium meleagridis）卵囊，根据隐孢子虫18S rDNA基因序列设计合成引物，用PCR扩增了卵囊基因组DNA大小586bp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，将测得的序列用Dnastar软件分析并与国外已发表的相应序列进行了同源性比较，并绘制了系统发育进化树。结果初步建立了火鸡隐孢子虫的PCR检测方法，序列分析显示长春外国语源火鸡隐孢子虫与国外9株隐孢子虫相应序旬同源性在82.7%-99.8%之间，其中与国外火鸡源火允隐孢子虫相应序列同源性为85.3%；与C.felis同源性最低，与C.muris同源性最高。本研究为火鸡隐孢子虫病诊断及该病分子流行病学研究打下了良好基础。     

家蚕核糖体18S RNA基因的序列分析及分子系统学研究

为研究家蚕18S DNA基因的特点及分子进化,以家蚕丝腺为材料提取家蚕基因组DNA,通过PCR扩增、测序鳞翅目家蚕(Bombyx mori)核糖体小亚基18S RNA基因(18S rDNA)的全序列,将该序列与等翅目、直翅目、衤责翅目、鞘翅目、膜翅目、双翅目、捻翅目、弹尾目、蜉蝣目各一种昆虫的18S rDNA进行了比较。用DNAstav软件分析并进行序列比对,结果表明,昆虫18S rDNA有4段序列较为保守,以18S rDNA比对的第2保守区段构建的分子系统发育树表明鳞翅目和双翅目、膜翅目、鞘翅目进化关系最近,等翅目、直翅目、衤责翅目进化上较为接近,捻翅目昆虫与弹尾目昆虫的亲缘关系较为接近,捻翅目在分类上应是一种古老的昆虫。     

基于18S rRNA和HSP70基因序列的隐孢子虫种系发育分析

为阐明河南区域隐孢子虫分子流行病学特点,用PCR技术扩增分离虫株的18S rRNA基因全序列和HSP70基因序列,并对扩增片段进行测序。用PAUP 4.0和TREEPUZZLE 4.1构建进化树,试图从分子水平证明河南省不同地区不同宿主来源隐孢子虫的遗传特征,以阐明隐孢子虫病的分子流行病学特点。通过18S rRNA基因全序列和HSP70基因序列分析,其结果：河南人源隐孢子虫分离株为Cryptosporidium parvum鼠基因型;河南鹿源隐孢子虫分离株为C. parvum鹿基因型;河南猪源隐孢子虫的2个分离株均为C. parvum猪基因I型,即C. suis;河南鹌鹑源的隐孢子虫2个分离株分别为C. baileyi和C. meleagridis;河南乌鸡源隐孢子虫和鸵鸟源隐孢子虫分离株均为C. baileyi;河南牛源隐孢子虫分离株为C.andersoni。     

伊犁河谷新疆褐牛隐孢子虫感染情况调查

为了解伊犁河谷区域新疆褐牛隐孢子虫病流行情况,从该地区的伊宁市和察布查尔锡伯自治县的4个养殖场采集356份粪便样品,提取基因组DNA,以隐孢子虫小亚基核糖体DNA(SSU rDNA)为靶基因,进行套式PCR扩增,并对阳性样品进行序列分析.结果显示:伊宁市和察布查尔锡伯自治县各有1个养殖场的新疆褐牛发现隐孢子虫感染,总的...     

提高猪磷利用率的分子生物学方法

本文从分子生物学方法的3个方面来论述提高猪对磷的利用率:1)通过添加经分子生物学改造的植酸酶来提高饲料磷的消化率;2)通过遗传方法改进大豆、玉米磷的水平来减少猪粪磷的含量;3)通过基因编码植酸酶来提高动物的代谢潜能(转植酸酶基因猪)。     

Serological characterisation of Actinobacillus pleuropneumoniae isolated from pigs in 1993 to 1996

OBJECTIVES: To clarify the serological identity of the prototype strain of a group of Actinobacillus pleuropneumoniae isolates that could not be serotyped in previous studies and to establish the serovar of 378 isolates of A pleuropneumoniae obtained from pigs in Australia over the period 1993 to 1996. DESIGN: After initial validation, QGD and IHA tests were used to characterise the prototype isolate (HS143) selected to represent the cross-reacting isolates that were found in a previous study. Next, 378 recent field isolates of A pleuropneumoniae were characterised using the existing gel diffusion serotyping technique and/or the IHA or QGD tests. RESULTS: The indirect haemagglutination test was shown to be capable of correctly recognising the reference strain for all serovars except serovar 11. While the quantitative gel diffusion test was not as effective as indirect haemagglutination, it could recognise serovar 11. When the two tests were used to examine the prototype strain (HS143) of the cross-reactive isolates, the results indicated that HS143 is serologically distinct from all 12 of the recognised serovars of A pleuropneumoniae. However, as HS143 was subsequently identified as serovar 12 by one of the leading international reference laboratories, the antiserum to isolate HS143 was used as the serovar 12 antiserum. A total of 346 of the 378 A pleuropneumoniae field isolates examined could be confidently serotyped with almost 90% of the isolates being either serovar 1 (104 isolates); serovar 7 (83 isolates) or serovar 12 (142 isolates). A range of other serovars and some cross-reactive isolates made up the remainder of the isolates. CONCLUSION: The serovar 12 antiserum produced against the international reference strain (1096) does not recognise Australian serovar 12 isolates. The antiserum raised against isolate HS143 does recognise the Australian serovar 12 isolates. The dominant serovars of A pleuropneumoniae infecting Australian pigs are (in decreasing order) serovars 12, 1 and 7.     

拉合尔钝缘蜱的形态学及分子生物学鉴定

试验旨在建立拉合尔钝缘蜱的分子生物学鉴定方法。从新疆地区绵羊体表采集寄生蜱,借助体视显微镜和电子显微镜对其进行形态学特征的准确鉴别,初步筛选出疑似拉合尔钝缘蜱。经PCR扩增、测序获得其18S rDNA、16S rDNA及线粒体色素氧化酶亚基Ⅰ基因（cytochrome oxidase Ⅰ,COⅠ）序列,结合GenBank数据库中参考序列,比对分析同源性并构建系统进化树,进行遗传距离评估。本研究全面、清晰地揭示了拉合尔钝缘蜱卵圆形背板、背部圆形盘窝等显微形态特征的细节。同时,在基于16S rDNA与COⅠ序列的邻位相接系统进化树中,拉合尔钝缘蜱分布于两大进化枝之一的软蜱科,同种聚类良好,且拉合尔钝缘蜱种内K2P遗传距离为0~0.3%,本研究方法可快速、准确鉴定拉合尔钝缘蜱物种。     

Morphological and Molecular Biology Identification of Ornithodoros lahorensis

This study was to establish a method for the identification of Ornithodoros lahorensis with molecular biology. The samples of Ornithodoros lahorensis were collected from sheep in Xinjiang region and the morphological characters were screened by stereo microscopy and electronic microscopy. Then the 16S rDNA,18S rDNA and cytochrome oxidase Ⅰ(COⅠ) of samples were amplified by PCR and subsequently sequenced. Then the analysis of genetic divergences and Neighbor-Joining (NJ) phylogenetic tree were carried out based on the sequences acquired from Ornithodoros lahorensis,combined with the reference sequences of GenBank database. In this study,the comprehensive and clear micromorphological traits of ovoid scutum,round fovea of Ornithodoros lahorensis were provided. Besides,the DNA sequences of Ornithodoros lahorensis were assembled together with sequences of Argasidae and form monophyletic clades in the 16S rDNA and COⅠ based Neighbor-Joining trees. According to the intraspecific K2P genetic distances of Ornithodoros lahorensis (0~0.3%),we determined that the molecular biology method based on 16S rDNA and COⅠ could rapidly and accurately identify the species of Ornithodoros lahorensis.     

猪源隐孢子虫卵囊的分离及基因型鉴定

应用RT-PCR方法对南京、上海和合肥猪源隐孢子虫卵囊SSU rRNA部分序列进行扩增,产物测序后提交GenBank,收录号为DQ855266、DQ855267;用BLAST和DNAStar软件与GenBank参考序列进行比较,分析其同源性,绘制系统发育进化树,结合卵囊形态学观察和对小鼠、大鼠、兔、山羊和鸡的传染性试验确定隐孢子虫种类或基因型。结果表明,3地区猪源隐孢子虫分离株与微小隐孢子虫(C.parvum)同源性达94%~100%,与C.parvummouse型有99.8%~100%的同源性,并处于进化树的同一分支。因此,3地区猪源隐孢子虫是C.parvummouse型,提示猪和鼠之间存在交叉传播的可能。     

Epidemiological studies of pig diseases: 1. Use of French protocols for risk factor assessment to predict the health status of Australian herds

Objective To determine in Australian pig herds the accuracy of French protocols for risk factor assessment.
Procedure Data on health indicators and risk factors were collected for three syndromes, 'pre-weaning diarrhoea', 'post-weaning diarrhoea' and 'respiratory problems', using the French protocols. The protocols were used on 118 occasions in 32 Western Australian pig herds during 3 years (1988 to 1991).
Results There was a wide variation in pre-weaning performance, for example growth rate was 107 to 273 g/day (< 200 g/day in 33% of herds). Respiratory lesions at weaning were associated with poor pre-weaning performance. Post-weaning (21 days after weaning) growth rate was 114 to 408 g/day (< 250 g/day in 54% of herds). In the grower herds, 91% of herds had pneumonia, and growth rate was 439 to 625 g/day (< 550 g/day in 54% of herds). Pleurisy as well as pneumonia was associated with reduced growth rate. The risk factor most closely associated with respiratory health status was air volume per pig.
Conclusion Risk factors were most accurate at predicting the health status in post-weaning problems. A weaning weight of at least 7.9 kg and weaning age of 30 days optimised weaner performance. Stocking densities and shed designs providing at least 3 m³ air volume and 0.6 m² floor space per pig throughout the growing phase should be considered for an improved respiratory health status. Australian pig sheds often do not provide a satisfactory environment for optimum health. The technique of risk factor assessment as an aid to the maintenance of health in pig herds is applicable in Australia, but further research is necessary to determine the most important Australian risk factors.     

Concurrent Cryptosporidium and parvovirus infections in a puppy

Cryptosporidium parvum, an intestinal coccidian parasite, was isolated from faeces and intestinal biopsies of a 9-week-old puppy with acute parvoviral gastroenteritis. Gene sequence analysis identified a Cryptosporidium genotype not previously recorded in Australia. The puppy recovered after treatment with crystalloid fluids, synthetic and natural colloids and jejunostomy tube feeding.     

小球隐孢子虫gp15基因的克隆与核苷酸序列分析

为了给小球隐孢子虫(Cryptosporidium parvum)核酸疫苗的研制提供基因材料，用聚合酶链式反应(PCR)技术，从牛源小球隐孢子虫基因组中扩增了子孢子表面蛋白CPl5的gpl5基因(413bp)，然后将其克隆到pMDl8-T载体中，用Sanger’s双脱氧法对重组质粒中的插入片段进行序列分析。将测得的核苷酸序列及其推导的氨基酸序列与国外报道的序列进行同源性比较，结果表明核苷酸同源性为99．2％，氨基酸同源性为100％。     

贵州地区紫云花猪腹泻病原菌的分离鉴定及耐药性分析

为了鉴定贵州地区紫云花猪腹泻病原菌,分析其耐药性,试验采用细菌学常规鉴定、16SrRNA基因测序、K-B药敏纸片法对从贵州地区不同养猪场采集的患腹泻紫云花猪肝脏、肛拭子、粪便等样品196份进行细菌分离鉴定,并分析其耐药性。结果显示,从采集的196份样品中分离得到了60株大肠杆菌、35株沙门菌、20株志贺菌,分离的60株大肠杆菌对庆大霉素、阿莫西林、强力霉素等5种药物的耐药率在70.0%以上,对其他药物耐药率在15.0%~40.0%之间,耐11、10种药物的菌株最多,分别占分离菌株31.7%、23.3%;分离的35株沙门菌对氨苄西林、阿莫西林、氟苯尼考等5种药物的耐药率在58.3%以上,对其他药物耐药率在48.6%~17.1%之间,耐10、9种药物的菌株最多,分别占分离菌株25.7%、22.9%;分离的20株志贺菌对氨苄西林、阿莫西林、新霉素等9种药物的耐药率在65.0%以上,对其他药物的药物耐药率在25%~35%之间,耐9、8种药物的菌株最多,分别占分离菌株30.0%、20.0%。本研究为该地区紫云花猪细菌性腹泻的防控提供研究基础。     

刚地弓形虫18S rDNA基因的克隆与序列分析

采用PCR方法从弓形虫RH株和CN株总DNA中分别扩增到18S rDNA基因，与pGEM-T easy vector连接，并进行DNA测序分析。结果表明，2个虫株均扩增出1745bp的片段，用DNAMAN软件对其与GenBank上2个虫株相应序列进行同源性比较，4个虫株的同源性为99．34％。刚地弓形虫虫株在不同宿主和不同区域上存在着一定的差异。     

山羊毛虱的形态结构和分子标志研究

为了解山羊毛虱形态结构和分子标志,用电子显微镜和三维立体显微镜观察了采自山羊的山羊毛虱形态结构,测定了其18SrDNA和cox1基因序列,并基于比对,揭示其序列特点。形态观察发现,触角3节,第1节短粗,第2、3节细长;中胸气门1对,位于前胸两侧;腹部有气门6对;跗节3节。序列分析显示,本样虱、山羊毛虱、具边毛虱和牛毛虱四者的18SrDNA基因序列高度相似,不适于做种间鉴定。cox1序列极不保守。     

四川省汶川县两种牛梨形虫的分离鉴定

自四川省汶川县黄牛体表采集长角血蜱的饥饿或半饱血成虫,带回实验室感染除脾牛.血液涂片检查发现,感染后第10 d,病牛血液中出现一种大型巴贝虫,感染后第24 d,出现一种小杆形的泰勒虫.形态学观察和18 S rRNA基因测序和进化关系分析证明,它们分别为卵形巴贝虫与瑟氏泰勒虫.     

伊氏锥虫、马媾疫锥虫、布氏锥虫、刚果锥虫的18S rDNA部分序列测定与系统发育关系

对伊氏锥虫（Trypanosoma evansi）：新疆株（XJCA）、湖北株（HBM）、云南株（YNB）、广东株（GDB2）；马媾疫锥虫（Trypanosoma equiperdum）、布氏锥虫（Trypanosoma brucei）、刚果锥虫（Trypanosoma congolense）提取基因组DNA，根据已报道的伊氏锥虫株18SrDNA基因序列设计合成引物，用PCR扩增了锥虫虫株基因组DNA,伊氏锥虫新疆株、湖北株、云南株、广东株、布氏锥虫、刚果锥虫均为373bp的片段；马媾疫锥虫为372bp的片段，PCR产物经电泳鉴定后用试剂盒回收纯化，纯化后PCR产物经连接、转化后测序，将测得的序列用DNAMAN软件分析并与国外已发表的相应序列进行了同源性比较，并绘制了系统发育进化树。结果与国外AJ009153、AJ223564、D89527株同源性达到99％～100％，与另外11株同源性75％。本研究为锥虫分子流行病学研究及分类研究打下基础。     

菲菜氏温扬球虫18S rDNA基因的扩增与克隆分析

菲莱氏温扬球虫是鸭球虫病的重要病原之一,为了寻找种特异性的遗传标记,本研究采集广东省某鸭场的新鲜鸭粪,通过Sheather's蔗糖漂浮法收集球虫卵囊,经形态学鉴定为菲莱氏温扬球虫;提取该球虫DNA样品,经过PCR扩增,首次获得了该虫的18S rDNA基因部分片段;对该基因进行了克隆和测序,比较了该虫株与其他原虫的亲缘关系.结果显示,对菲莱氏温扬球虫序列与艾美耳科其他球虫关系较近,系统进化树分析属于艾美耳科的另一分支.表明18S rDNA基因在鸭菲莱氏温扬球虫的分类鉴定上是一种有效的分子标记.