Amer Said, Harfoush Mohamed, He Hongxuan
Department of Zoology, Faculty of Science, Kafr-El Sheikh University, Kafr El Sheikh, Egypt.
J Egypt Soc Parasitol. 2010 Aug;40(2):349-66.
Cryptosporidium infections in cattle result in considerable'economic loss as well as a significant source for zoonotic infection. This study was devoted to spot analysis on Cryptosporidium parasites derived from dairy cattle at Kafr El Sheikh Province, Egypt, using morphological and molecular tools. Fecal specimens from neonatal calves as well as adult cattle were screened for Cryptosporidium oocysts using modified Ziehl-Neelsen technique. Oocysts in positive samples were concentrated using sugar floatation technique. Small size oocysts from calves and large size ones from adults were identified microscopically with measures correspond to those of C parvum and C. muris-C. andersoni, respectively. DNA was extracted from 8 positive specimens; 4 harbored small and 4 had large oocysts and used for PCR amplification, RFLP analysis and nucleotide sequence. RFLP analysis revealed 2 types of banding patterns coinciding with those of Cryptosporidium parvum and C. muris-C. andersoni. Sequence analysis of amplified fragments of small subunit of ribosomal RNA (SSU rRNA) and heat shock protein (HSP70) genes were used as markers for species identification and genotyping of the parasite. Homology search and phylogenetic analysis of the generated sequences versus those deposited in Genbank revealed that small oocysts were belong to C. parvum genotype II, whereas large ones were belong to C. andersoni.
牛的隐孢子虫感染会造成相当大的经济损失,也是人畜共患感染的重要来源。本研究致力于利用形态学和分子工具,对埃及卡夫尔谢赫省奶牛源的隐孢子虫进行分析。采用改良齐-尼氏技术,对新生犊牛和成年牛的粪便样本进行隐孢子虫卵囊筛查。阳性样本中的卵囊采用蔗糖漂浮技术进行浓缩。通过显微镜鉴定,犊牛的小尺寸卵囊和成年牛的大尺寸卵囊分别与微小隐孢子虫和鼠隐孢子虫-安氏隐孢子虫的特征相符。从8个阳性样本中提取DNA;其中4个含有小卵囊,4个含有大卵囊,并用于PCR扩增、RFLP分析和核苷酸测序。RFLP分析显示出2种条带模式,分别与微小隐孢子虫和鼠隐孢子虫-安氏隐孢子虫的条带模式一致。核糖体RNA小亚基(SSU rRNA)和热休克蛋白(HSP70)基因扩增片段的序列分析被用作该寄生虫物种鉴定和基因分型的标记。将生成的序列与Genbank中 deposited的序列进行同源性搜索和系统发育分析,结果表明小卵囊属于微小隐孢子虫II型,而大卵囊属于安氏隐孢子虫。