Southern Regional Research Centre (ICAR-CSWRI), Mannavanur, Kodaikanal, Tamil Nadu, 624103, India.
ICAR-Central Sheep and Wool Research Institute, Avikanagar, Rajasthan, 304501, India.
Acta Parasitol. 2022 Dec;67(4):1626-1633. doi: 10.1007/s11686-022-00607-4. Epub 2022 Sep 8.
Tape worm infection is common among sheep at SRRC, Mannavanur, Palani hills, Tamil Nadu, India. The aim of the present study is to find out the cestode species infecting the sheep being maintained at SRRC, Mannavanur, by means of molecular method.
During the second week of June 2021, the hogget flock of sheep (comprising both Bharat Merino and Avikalin sheep breeds) was drenched on empty stomach with commercial preparation of anthelmintic drug containing Niclosamide plus Albendazole, as per the standard dose specified by the manufacturer (Niclozole™: each 5 ml contains 500 mg of Niclosamide and 150 mg of Albendazole: dose for sheep-10 ml/15 kg body weight). The tapeworms expelled in dung by the drug-treated sheep were collected, washed in PBS (pH 7.2), and fixed in between two glass slides using 10% formalin. Furthermore, cytochrome c oxidase subunit I (Cox-I) gene-based PCR was carried out. Only partial sequence (1593 bp) of Cox-I gene of Moniezia expansa from Sheep at SRRC, Mannavanur, Tamil Nadu, India was obtained by PCR. The PCR amplified fragment was cloned into pGEM-T vector and the recombinant plasmid was sequenced. The obtained nucleotide sequences of Cox-I gene of the M. expansa from Indian sheep were analysed with that of 27 more cestode species from different mammalian species (available in GenBank) using bioinformatics tools.
The species of the tapeworm was identified as Moniezia species by the Department of Veterinary Parasitology, VC& RI, Orathanadu, TANUVAS by the standard Acidic alum carmine staining method. Due to the ambiguity in the conventional method, Cox-I gene-based PCR and subsequent gene sequencing protocols were used for the identification of the species of cestode infecting sheep at SRRC, Mannavanur, and it was confirmed as M. expansa upon BLAST analysis. Moniezia expansa from SRRC, Mannavanur is having 100% sequence identity at nucleotide level with that of M. expansa from Sengal/Ethiopia. M. benedeni shared 87-88% nucleotide identity with Indian M. expansa. With taenids, the share of percent nucleotide identity of Indian M. expansa ranged from 79 to 81%. M. expansa from Indian sheep was clustering with other anaplocephalids from various mammalian species in the analysis of phylogenetic tree based on Cox-I nucleotide sequences.
From the present study, it is concluded that M. expansa is the anoplocephalid cestode infecting the sheep at Mannavanur, Tamil Nadu, India. To our knowledge, this is the first report on partial nucleotide sequences of Cox-I gene of M. expansa from Sheep of Indian peninsula. An investigation on the involvement of oribatid mites as the vector in the transmission of M. expansa among sheep at SRRC, Mannavanur needs to be carried out.
在印度泰米尔纳德邦帕拉尼山的曼纳万努尔的 SRRC,绵羊经常感染带绦虫。本研究的目的是通过分子方法确定在 SRRC 饲养的绵羊感染的绦虫种类。
在 2021 年 6 月的第二周,给空腹的肥羊(包括 Bharat Merino 和 Avikalin 绵羊品种)服用含有硝氯酚和阿苯达唑的驱虫药商业制剂,按制造商规定的标准剂量(Niclozole ™:每 5 毫升含 500 毫克硝氯酚和 150 毫克阿苯达唑:绵羊剂量为 10 毫升/15 公斤体重)。用驱虫药处理过的羊排出的绦虫被收集起来,用 PBS(pH7.2)冲洗,并用 10%福尔马林固定在两块载玻片之间。此外,还进行了细胞色素 c 氧化酶亚基 I(Cox-I)基因的 PCR。仅从印度泰米尔纳德邦曼纳万努尔的 SRRC 的绵羊中获得了 Moniezia expansa 的 Cox-I 基因的部分序列(1593bp),通过 PCR。将 PCR 扩增片段克隆到 pGEM-T 载体中,并对重组质粒进行测序。使用生物信息学工具,对来自不同哺乳动物物种的 27 种更多绦虫物种(可在 GenBank 中获得)的 Cox-I 基因与从印度绵羊中获得的 M. expansa 的核苷酸序列进行了分析。
通过兽医寄生虫学系的标准酸性氧化铝卡明染色法,由 VC&RI,Orathanadu,TANUVAS 的部门确定这种绦虫的物种为 Moniezia 物种。由于常规方法存在歧义,因此使用基于 Cox-I 基因的 PCR 和随后的基因测序方案来鉴定曼纳万努尔的 SRRC 感染绵羊的绦虫物种,BLAST 分析证实为 M. expansa。曼纳万努尔的 M. expansa 在核苷酸水平上与来自塞内加尔/埃塞俄比亚的 M. expansa 具有 100%的序列同一性。与 taenids 相比,印度 M. expansa 的核苷酸同一性百分比为 79-81%。基于 Cox-I 核苷酸序列的系统发育树分析表明,印度 M. expansa 与来自各种哺乳动物物种的其他无钩绦虫聚类在一起。
从本研究中可以得出结论,M. expansa 是感染印度泰米尔纳德邦曼纳万努尔绵羊的无钩绦虫。据我们所知,这是印度羊莫尼兹绦虫 Cox-I 基因部分核苷酸序列的首次报道。需要对蜱螨作为 M. expansa 在 SRRC 之间传播的媒介在绵羊中的作用进行调查。