Occurrence and genotype characterization of Giardia duodenalis in goat kids from the Canary Islands, Spain

Giardia duodenalis (syn. Giardia lamblia, Giardia intestinalis) is a wide-spread intestinal protozoa of both humans and animals. Although giardiosis in goat is commonly asymptomatic, young kids may bear an enteric disease associated with persistent diarrhoea and delayed weight gain. In the present study we have analysed the occurrence of Giardia in 315 young goat kids (2–6 months old) from Gran Canaria Island (Spain) through visualization of faecal cysts. The identification of genotypes of G. duodenalis among the farms was attained by nested PCR of the triophosphate isomerase (TPI) and single PCR of β-giardin genes and subsequent sequencing. Positive samples were found in 42.2% of the animals and 95.5% of the farms. Goat faecal specimens were positive for only livestock-associated G. duodenalis assemblage E genotype for both TPI and β-giardin genes. The genetic analysis of these two loci revealed the presence of different haplotypes among the farms included in the survey and high homology with homologous genes from cattle and sheep. Altogether, the data presented here provide additional information to the prevalence and genetic characterization of Giardia isolates. The absence of assemblages A and B in this study suggests that zoonotic transmission of Giardia from goats could be of low epidemiological significance, although these findings should be validated in studies including other geographical areas, age groups and larger number of samples.     

斑点免疫结合试验对蓝氏贾第鞭毛虫感染者粪中特异性抗原的检测

应用蔗糖密度梯度离心技术从蓝氏贾第鞭毛虫感染者的粪便中分离纯化贾第虫包囊，以此包囊免疫家兔，获得免疫血清，经大肠杆茵吸收后建立斑点免疫结合试验，检测粪中贾第虫特异性抗原。以此法检测３９例贾第虫感染者粪便，有３６例出现阳性斑点，阳性检出率为９２．３％。以超声粉碎的贾第虫包囊抗原为标准，３６例阳性标本中，有３５例标本贾第虫特异性抗原蛋白含量分布在３９～６９ｎｇ／ｍＬ范围内，１例为１３８ｎｇ／ｍＬ。     

中国人源蓝氏贾第虫病毒基因组全长cDNA克隆及序列测定

从中国人源蓝氏贾第虫北京株(BEIJ88／BTMR1／1)体外纯培养的电镜负染和超薄切片观察到蓝氏贾第虫病毒粒子。该病毒位于感染早期贾第虫的细胞质中，感染晚期的细胞核中。根据国外发表的蓝氏贾第虫病毒序列设计了6对互相重叠的引物。用这6对引物对从中国人源蓝氏贾第虫北京株发现的蓝氏贾第虫病毒基因组进行RT—PcR，将产物连接到pMD18-T载体中并转化入DH5a感受态菌，送上海生工测序，通过BLAST对Gen-Bank进行同源性搜索。结果 测得我国人源蓝氏贾第虫病毒基目组全长为6273bp，与国外报道的蓝氏贾第虫病毒序列同源性为95％，编码的氨基酸同源性为90％。     

High prevalence of Giardia detected in cats by PCR

Microscopy, PCR and a Giardia CELISA test were used to determine the prevalence of Giardia in 40 faecal samples obtained from domestic cats in the Perth metropolitan area. A prevalence of 5, 80 and 60% was found by the tests, respectively. The results show that more sensitive techniques such as PCR may be necessary, and may yield more reliable results, in the detection of low levels of Giardia in domestic cats.     

Endoscopic Aspiration of Intestinal Contents in Dogs and Cats: 394 Cases

Medical records from 394 dogs and cats that had endoscopic aspiration of intestinal contents for identification of Giardia sp. trophozoites were retrospectively reviewed. The most common indications for endoscopy were chronic vomiting (152), chronic diarrhea (108), chronic vomiting and diarrhea (58), and acute vomiting (33). Metronidazole had been previously administered to 111 animals (28.2%), and to 58.6% of those with chronic diarrhea. Six aspirate samples (1.5%) were positive for Giardia sp. In 3 of these cases a single fecal flotation identified Giardia cysts before endoscopy. The authors conclude that intestinal aspiration in animals from a primarily referral population undergoing upper gastrointestinal endoscopy rarely identifies Giardia and should not be routinely performed. However, animals in which zinc sulfate flotation was not performed or those that did not previously receive metronidazole might benefit from intestinal aspiration.     

两株犬源贾第虫tpi基因的基因型分析

采用巢式PCR鉴定广东两株犬源贾第虫(GD1和GD2)的基因型。运用碘液染色对犬粪便中贾第虫进行鉴定,提取DNA后经巢式PCR扩增tpi基因,扩增产物测序后用BLAST和DNAStar软件进行同源性和系统发育分析。结果表明,通过tpi基因分析,GD1与L02120的同源性为100%,种系发育树上位于同一分支;GD2与DQ220289的同源性为99.1％,种系发育树上两者在同一分支。广东犬源贾第虫GD1为人畜共患的A1型,GD2为犬的D型。     

Johne's disease in sheep

Extract

Inoculation of susceptible laboratory animals with a suspension of kidney tissue is a widely used method of diagnosing leptospirosis in livestock and of isolating leptospiral serotypes. A recent experience has indicated a potential cause of failure which may not be generally realized in laboratories using this technique.     

青海省海北地区牦牛源贾第虫检测与基因型分析

为研究青海省海北地区牦牛贾第虫的感染情况及虫种基因型,对青海省祁连县、海晏县和刚察县的297份牦牛粪样采用蔗糖密度梯度离心法纯化,之后用免疫荧光方法对贾第虫进行鉴定,对阳性及疑似阳性样品采用基于18SrRNA和谷氨酸脱氢酶(gdh)基因的套式PCR扩增,并对扩增产物进行测序。将测序结果与GenBank中的贾第虫序列进行比对分析。免疫荧光抗体试验结果显示,共检出24份贾第虫阳性粪样,总阴性率为8.1%。套式PCR扩增结果显示,24份阳性样品中18SrRNA基因扩增阳性22份,gdh基因扩增阳性18份,产物大小分别为292bp和432bp。序列分析表明,分离的虫种均为牦牛源肠贾第虫,基因型为集聚体E,未发现人畜共患基因型。     

用犬贾第虫包囊人工感染幼犬后排虫规律研究

用大量犬贾第虫包囊人工感染幼犬后进行粪便检测,结果表明其排虫呈周期性,接虫后第8天检测到贾第虫包囊。接虫后第18天出现第一个排虫高峰,高峰期持续1～2 d。高峰期过后2～3 d再次出现一个高峰期,但高峰期持续的时间都不超过2 d。