鸡组织滴虫病PCR病原学诊断方法的建立

为建立鸡组织滴虫(H.meleagridis)的PCR检测方法,本研究以确诊的感染火鸡组织滴虫的阳性鸡的肝组织DNA为模板,设计针对18S rRNA基因高度保守的特异性引物,建立组织滴虫病的PCR诊断方法。敏感性试验显示阳性样品组织DNA的最低检出限为4 ng/μL。特异性试验表明与其他常见鸡寄生虫的DNA样品均无交叉反应。该PCR方法对临床样品的检出率为100%,与组织病理学诊断结果符合率为100%。该诊断方法敏感、特异,可以用于组织滴虫病的临床诊断。     

鸡组织滴虫病的中西医结合疗法

鸡组织滴虫病又名盲肠肝炎或黑头病,是鸡和火鸡的原虫病,由火鸡组织滴虫寄生于盲肠和肝脏引起,以肝的坏死和盲肠溃疡为特征,也发生于野雉、孔雀和鹌鹑等鸟类. 鸡组织滴虫病由于症状的不典型性经常被养殖户忽视,而且很容易和球虫病混淆,希望引起养殖户的注意,不要盲目用药,现将诊治方法介绍如下. 1 病原学 组织滴虫病的病原为火鸡组织滴虫,为多样性虫体,大小不一. 火鸡组织滴虫的生活史与异刺线虫和存在于鸡场土壤中的几种蚯蚓密切相关联. 鸡盲肠内同时寄生着组织滴虫和异刺线虫,组织滴虫可钻人异刺线虫体内,在其卵巢中繁殖,异刺线虫卵可随鸡粪排到外界,成为重要的感染源,土壤中的蚯蚓吞食异刺线虫卵后,组织滴虫可随虫卵进入蚯蚓体内.当鸡采食这种蚯蚓后,便可感染组织滴虫病.     

1例鸡异刺线虫病与组织滴虫病混合感染的诊疗与分析

鸡异刺线虫病又称盲肠线虫病,是由异刺线虫科(Heter-akidae)异刺线虫属(Heterakis)的鸡异刺线虫(H.gallinae)寄生于禽类的盲肠内而引起的一种寄生虫病。鸡异刺线虫不仅自身可单独致家禽发病,且它的虫卵还能携带组织滴虫,成为鸡组织滴虫病的传播者。鸡组织滴虫病又称鸡盲肠肝炎,俗称黑头病,是由组织滴虫属的火鸡组织滴虫寄生于禽类的盲肠和肝脏而引起的一种原虫病,其主要特征是盲肠发炎和肝脏表面纽扣状溃疡。     

一例鸡组织滴虫病的诊治

鸡组织滴虫病又名盲肠肝炎、黑头病,是由单毛滴虫科组织滴虫属的火鸡组织滴虫寄生于禽类盲肠和肝脏中引起的原虫病.     

鸡组织滴虫病的防治

正鸡组织滴虫病是由火鸡组织滴虫引起,以盲肠芯和肝脏坏死为特征,可对养鸡生产造成严重经济损失。在各种禽类中,火鸡的易感性最强。组织滴虫可以在鸡的盲肠及肝脏引起非常典型的特征性病变,因此,对病死鸡进行病理剖检即可做出临床诊断。另外,也可通过病理切片镜检、分子生物学方法如聚合酶链式反应(PCR),以及寄生虫培养等实验室检测技术等,对本病进行确断。1组织滴虫病近年来在黄羽肉鸡和白羽肉种鸡中多发     

鸡组织滴虫病的诊治

<正>鸡组织滴虫病又称鸡盲肠肝炎、鸡黑头病,是由组织滴虫属的火鸡组织滴虫寄生于鸡的盲肠和肝脏引起的一种原虫病。本病以肝脏产生特征性坏死病灶和盲肠溃疡为特征。有的鸡因血液循环障碍,鸡冠发绀。目前,台安县不同程度的发生了鸡组织滴虫病,给养禽生产造成了一定损失。     

一例混合散养鸡、鹅组织滴虫病的病理学诊断报告

就一例混合散养鸡、鹅组织滴虫感染导致死亡的病例进行了分析,介绍了混合散养鸡、鹅感染组织滴虫的病理学诊断、治疗方法以及防范措施。为临床混合散养鸡、鹅感染组织滴虫病识别及处置提供参考,同时为预防组织滴虫病的发生提供技术支持。     

雏鸡盲肠肝炎的诊断与防制

鸡盲肠肝炎是由组织滴虫属的火鸡组织滴虫(Histomonos meleagridis)寄生于禽类盲肠和肝脏引起的一种原虫病,又称组织滴虫病或黑头病[1].本病以肝脏肿大、表面散布大小不等的圆形、绿色或黄白色坏死溃疡和盲肠发炎肿大为特征.多发于雏火鸡和雏鸡,成年鸡也能感染,但病情较轻.     

鸡组织滴虫病的诊断与综合防治

鸡组织滴虫病由火鸡组织滴虫寄生于盲肠和肝脏引起,以肝坏死和盲肠溃疡为特征。由于鸡组织滴虫病症状不典型常被养殖户忽视,导致家禽生长发育迟缓,产蛋量下降,给畜牧业生产造成经济损失。1病原病原为火鸡组织滴虫,为多样性虫体。火鸡组织滴虫的生活史与异刺线虫和存在于鸡场土壤中的蚯蚓关系密切。鸡盲肠内同时寄生着组织滴虫和异刺线虫,组织滴虫可钻入异刺线虫体内,在其卵巢中繁殖,异刺线虫卵可随鸡粪排到外界,土壤中的蚯蚓吞食异刺线虫卵后，组织滴虫可随虫卵进入蚯蚓体内。当鸡食入这种蚯蚓后便可感染组织滴虫病。     

散养鸡慎防组织滴虫病

组织滴虫病是由毛滴虫科组织滴虫属的火鸡组织滴虫寄生于鸡等禽类盲肠和肝脏引起的疾病,又称“盲肠肝炎”或“黑头痛”。近些年随着对禽类产品质量的要求提高,散养鸡和鸡蛋受到很多消费者青睐,养殖户也瞄准了散养鸡市场。但在养殖过程中要慎防组织滴虫病。本文就如何防治组织滴虫病做一阐述。     

10株火鸡组织滴虫18S rRNA基因的克隆及进化分析

应用聚合酶链反应(PCR)鉴定湖南娄底(简称HMLD1-3)、湘潭(HMXT1-2)、永州(HMYZ1-3)和宁乡(HMNX1-2)共10株火鸡组织滴虫,并用18S rRNA部分序列重构火鸡组织滴虫与其它相近原虫的种群遗传关系.作者通过PCR扩增火鸡组织滴虫虫株的18S rRNA部分序列,将PCR扩增出的片段纯化后克隆...     

Molecular characterization of Babesia canis canis isolates from naturally infected dogs in Poland

Babesia canis has generally been considered the only large Babesia to infect dogs. In this study, we used PCR to detect and characterize B. canis canis isolated from naturally infected dogs in Poland by amplifying and sequencing a portion of the 18S ribosomal RNA (rRNA) gene. Venous blood samples were collected from 76 Babesia-symptomatic dogs. A 559-bp fragment of the B. canis canis 18S rRNA gene was amplified by PCR. The PCR products were then digested with HincII restriction enzyme, and isolates were classified according to whether they were cut (group A) or not (group B) by this endonuclease. Sequencing of the PCR products from the isolates led to the identification of seven sequence variants (four in group A, and three in group B). Sequences were compared with GenBank sequences, and alignments showed that all B. canis canis isolates from Europe may be classified into groups A or B as defined in our study.     

Detection of Histomonas meleagridis in turkeys cecal droppings by PCR amplification of the small subunit ribosomal DNA sequence

Histomonas meleagridis is a protozoan parasite that may cause histomoniasis, a disease of gallinaceous fowl characterized by necrotic typhlitis, hepatitis and high mortality. Diagnosis of this disease is based on direct identification or on cultivation of the parasite. With the aim of developing more sensitive, rapid and useful tools for parasite detection, PCR that amplified a DNA target of 209 pb of the 18S rRNA gene was designed to detect the genome of H. meleagridis and to differentiate it from the genome of Tetratrichomonas gallinarum, another common protozoan parasite of fowl. The sensitivity of the test was evaluated using serial diluted samples of cultured H. meleagridis and showed positive amplification for concentrations comprised between 10 and 10(-1)parasites/ml of culture. The sensitivity for cecal droppings samples was assessed using spiked material and was comprised between 3 x 10(3) and 3 x 10(5)parasites/ml of stool. The reliability of the PCR for the detection of Histomonas infection was also evaluated by experimental infection of turkeys. Results of the PCR appeared to be in agreement with the development of the clinical signs and of the cecal lesions. The PCR developed in this study may be a useful tool in the detection and identification of H. meleagridis for rapid, routine screening as a supplement to direct identification or cultivation of the parasite.     

Development of a PCR test to diagnose Haemophilus parasuis infections.

A polymerase chain reaction (PCR) test was developed in order to improve the accuracy and speed of diagnosis of Haemophilus parasuis, an economically important respiratory pathogen that affects swine. The gene sequence of the 16S small subunit ribosomal RNA of H. parasuis (GenBank M75065) was compared with 56 16S sequences of related bacteria, including those frequently isolated from pig tissues. Two species-specific primers were designed: HPS forward and HPS reverse. The predicted size of the amplified PCR product was 821 bp. The PCR test could detect a minimum of 102 bacteria and 0.69 pg of DNA. Thirty-one H. parasuis isolates, including 12 different serovars and 19 field isolates, were positive using the PCR test. No amplification was observed when the test was run using DNA from 15 other bacterial species commonly isolated from swine tissues. A weak band was observed when the PCR test was performed using Actinobacillus indolicus DNA as template. Clinical samples tested by PCR included tissues and swabs from 5 animals naturally infected with H. parasuis and 1 experimentally infected animal. The PCR was positive in 26 of 30 clinical samples. Four samples showed weak bands, and these results were not considered positive. Haemophilus parasuis was isolated from 18 of 30 of these samples. Tissues from specific pathogen-free (SPF) pigs and from unrelated species were negative for H. parasuis isolation and PCR. The developed PCR was successfully used in the diagnosis of H. parasuis infection, especially when compared with traditional microbiology techniques.     

Identification of Theileria parva and Theileria sp. (buffalo) 18S rRNA gene sequence variants in the African Buffalo (Syncerus caffer) in southern Africa

Theileria parva is the causative agent of Corridor disease in cattle in South Africa. The African buffalo (Syncerus caffer) is the reservoir host, and, as these animals are important for eco-tourism in South Africa, it is compulsory to test and certify them disease free prior to translocation. A T. parva-specific real-time polymerase chain reaction (PCR) test based on the small subunit ribosomal RNA (18S rRNA) gene is one of the tests used for the diagnosis of the parasite in buffalo and cattle in South Africa. However, because of the high similarity between the 18S rRNA gene sequences of T. parva and Theileria sp. (buffalo), the latter is also amplified by the real-time PCR primers, although it is not detected by the T. parva-specific hybridization probes. Preliminary sequencing studies have revealed a small number of sequence differences within the 18S rRNA gene in both species but the extent of this sequence variation is unknown. The aim of the current study was to sequence the 18S rRNA genes of T. parva and Theileria sp. (buffalo), and to determine whether all identified genotypes can be correctly detected by the real-time PCR assay. The reverse line blot (RLB) hybridization assay was used to identify T. parva and Theileria sp. (buffalo) positive samples from buffalo blood samples originating from the Kruger National Park, Hluhluwe-iMfolozi Park, the Greater Limpopo Transfrontier Park, and a private game ranch in the Hoedspruit area. T. parva and Theileria sp. (buffalo) were identified in 42% and 28%, respectively, of 252 samples, mainly as mixed infections. The full-length 18S rRNA gene of selected samples was amplified, cloned and sequenced. From a total of 20 sequences obtained, 10 grouped with previously published T. parva sequences from GenBank while 10 sequences grouped with a previously published Theileria sp. (buffalo) sequence. All these formed a monophyletic group with known pathogenic Theileria species. Our phylogenetic analyses confirm the distinction between Theileria sp. (buffalo) and T. parva and indicate the existence of a single group of T. parva and two Theileria sp. (buffalo) 18S rRNA gene variants in the African buffalo. Despite the observed variation in the full-length parasite 18S rRNA gene sequences, the area in the V4 hypervariable region where the RLB and real-time PCR hybridization probes were developed was relatively conserved. The T. parva specific real-time PCR assay was able to successfully detect all T. parva variants and, although amplicons were obtained from Theileria sp. (buffalo) DNA, none of the Theileria sp. (buffalo) 18S rRNA sequence variants were detected by the T. parva-specific hybridization probes.     

长颈鹿血矛线虫ITS的PCR扩增与序列分析

目的利用分子生物学方法对来自长颈鹿皱胃的血矛线虫进行虫种鉴定。方法对样品XM9和XM11的核糖体DNA内转录间隔区(ITS-1、5.8 S、ITS-2)进行PCR扩增及序列分析,并与GenBank公布的血矛线虫(Hae-monchus)相应序列进行比较。结果来自长颈鹿皱胃的2条血矛线虫具有相同的ITS序列,5.8 S与ITS-1分别为153 bp、404 bp,与GenBank分布的捻转血矛线虫序列是一致的。ITS-2序列为231 bp,第753位是一个多态位点,该序列与来自国外的H.contortus,H.placei,H.longistipes存在0-18个碱基差异。结论来自长颈鹿的血矛线虫是捻转血矛线虫。     

Detection of DNA of Histomonas meleagridis and Tetratrichomonas gallinarum in German poultry flocks between 2004 and 2008

Between 2004 and 2008, 338 samples from 156 German turkey, chicken, and peacock flocks with suspected histomonosis (histomoniasis) were sent to the Institute for Poultry Diseases of the Free University Berlin. Most samples were from ceca or livers; the other samples were organ pools or were taken from other organs or the environment. In 108 samples from 65 flocks, histomonal DNA was detected by polymerase chain reaction (PCR). Tetratrichomonas gallinarum DNA was found in 5.3% of investigated samples from flocks infected with Histomonas meleagridis and in 27.4% of investigated samples from flocks that were not infected with H. meleagridis. For subtyping of the strains, the C-profiling method, a method used to analyze the internal transcribed spacer-1 (ITS-1) of the rRNA gene, was modified to be more specific for H. meleagridis. Results showed the presence of more than the three subtypes described so far. There was no clear correlation between the subtype and the host. By C-profiling the clonal cultures, heterogeneous ITS-1 sequences were shown to probably result from intragenomic differences between rRNA genes.     

Molecular detection of filarial nematode parasites in Japanese black bears (Ursus thibetanus japonicus) from Iwate Prefecture, Japan

This study aimed to detect filarial parasites in blood samples of Japanese black bears (Ursus thibetanus japonicus) collected from Iwate Prefecture, Japan. Positive amplicons were obtained from 26 out of 30 samples by nested PCR targeting 18S ribosomal RNA gene and first internal transcribed spacer regions. DNA sequences of Mansonella sp. close to M. ozzardi and Dirofilaria sp. were detected for eight and 11 positive amplicons, respectively. Co-infection was detected for the remaining seven amplicons. Dirofilaria sp. was identified as D. ursi by further genetic analysis of 5S ribosomal RNA gene sequence. The results of this study will contribute to further investigations of Japanese black bears for monitoring their risk as a reservoir of possible zoonotic filarial parasites.     

Use of a polymerase chain reaction assay for detection of Haemobartonella canis in a dog.

A polymerase chain reaction (PCR) originally developed for detection of Haemobartonella felis in cats was successfully used for detection of H canis in an 8-year-old spayed Great Dane. The dog had been splenectomized and was undergoing immunosuppressive chemotherapy at the time of diagnosis. Sequence analysis of the 16S ribosomal RNA gene revealed that the Haemobartonella spp infecting this dog was 97% homologous to the sequence previously reported for the Ohio strain of H felis. Clinical and hematologic abnormalities as well as identification of the organisms by use of light and electron microscopy supported the diagnosis of H canis. The PCR assay used for detection of H felis may be useful for the detection of H canis in dogs prior to blood donation, splenectomy, or treatment with immunosuppressive drugs.     

3株柔嫩艾美耳球虫28SrRNA基因部分序列的扩增与分析

本研究应用PCR技术扩增来自广东的3株柔嫩艾美耳球虫的28S rRNA基因部分序列,并与GenBank^TM登录的柔嫩艾美耳球虫、堆型艾美耳球虫、鼠肉孢子虫和刚地弓形虫虫株的相应序列进行比对分析。试验结果显示,柔嫩艾美耳球虫3个样品均获得1172 bp的28S rRNA基因部分有效序列,不同虫株序列没有差异,与GenBank^TM登录的柔嫩艾美耳球虫相应序列只有一个碱基差异,显示种内序列高度保守,而与堆型艾美耳球虫、鼠肉孢子虫、刚地弓形虫相应的序列存在不同程度的差异。结果表明,28S rRNA基因部分序列可作为研究艾美耳球虫种间及其他顶复门原虫遗传变异的标记。