Langkjaer R B, Vigre H, Enemark H L, Maddox-Hyttel C
Department of Veterinary Diagnostics and Research, Danish Institute for Food and Veterinary Research, Bülowsvej 27, DK-1790 Copenhagen V, Denmark.
Parasitology. 2007 Mar;134(Pt 3):339-50. doi: 10.1017/S0031182006001533. Epub 2006 Nov 1.
The genetic diversity of Cryptosporidium spp. and Giardia duodenalis from dairy cattle and pigs in Denmark was determined in the present study. Faecal samples from 1237 pigs and 1150 cattle originating from 50 sow herds and 50 dairy herds, respectively, were analysed for the presence of the two parasites by immunofluorescence microscopy. A large proportion of the (oo)cyst containing samples were selected for molecular characterization. Sequencing and phylogenetic analysis of the 18S rDNA locus and/or the HSP70 gene of 183 pig and 154 cattle isolates of Cryptosporidium revealed the presence of C. suis, pig genotype II, C. parvum (cattle genotype), C. bovis, Cryptosporidium deer-like genotype and a novel C. suis-like genotype. For both cattle and pigs, a host age-related change in distribution of species/genotypes was observed. The zoonotic C. parvum (cattle genotype) was most prevalent in young calves. For Giardia, 82 and 145 isolates from pigs and cattle, respectively, were analysed at the 18S rDNA locus and/or the gdh gene. Giardia isolates belonging to the zoonotic Assemblage A was found in both young and older calves, as well as in weaners and piglets, whereas cows seemed to be infected purely by isolates of the livestock group, Assemblage E.
本研究测定了丹麦奶牛和猪体内隐孢子虫属及十二指肠贾第虫的遗传多样性。分别从50个母猪群和50个奶牛群采集了1237份猪粪便样本和1150份牛粪便样本，通过免疫荧光显微镜分析这两种寄生虫的存在情况。选择了很大一部分含有（卵）囊的样本进行分子特征分析。对183份猪源和154份牛源隐孢子虫分离株的18S rDNA基因座和/或HSP70基因进行测序和系统发育分析，结果显示存在猪隐孢子虫、猪基因型II、微小隐孢子虫（牛基因型）、牛隐孢子虫、鹿样隐孢子虫基因型和一种新的猪隐孢子虫样基因型。在牛和猪中，均观察到物种/基因型分布与宿主年龄相关的变化。人兽共患的微小隐孢子虫（牛基因型）在幼龄犊牛中最为普遍。对于贾第虫，分别对82份猪源分离株和145份牛源分离株的18S rDNA基因座和/或gdh基因进行了分析。在幼龄和老龄犊牛以及断奶仔猪和仔猪中均发现了属于人兽共患集合A的贾第虫分离株，而奶牛似乎仅感染家畜组集合E的分离株。
