Fasciola hepatica from naturally infected sheep and cattle in Great Britain are diploid
Fasciola hepatica from naturally infected sheep and cattle in Great Britain are diploid
复制标题
DOI：
10.1017/s0031182015000499
复制
发表时间：
2015-08-01
期刊：
影响因子：
2.4
通讯作者：
Hodgkinson, J.
中科院分区：
文献类型：
--
作者：
Beesley, N. J.;Cwiklinski, K.;Hodgkinson, J.
二倍体（2n = 2x = 20）和三倍体（2n = 3x = 30）肝片形吸虫在英国已有报道，在亚洲也有二倍体、三倍体和混倍体（2x/3x）肝片形吸虫。存在，但很少有资料表明，如何常见的三倍体，特别是在英国侥幸。本文对565份F.从66只自然感染的英国绵羊和150只成年F.对35头自然感染的英国牛的肝脏进行了测定。所有715个这些寄生虫是二倍体的基础上观察到的10个二价染色体和精子（n = 335），或由于三倍体是无精子，精子单独（n = 380）。这是首次对F. hepatica field分离自英国，表明大多数F.从牛和羊中分离的肝细胞是二倍体，具有有性繁殖的能力。这些数据表明，三倍体，并通过推广孤雌生殖，是罕见的或不存在的野生英国F。肝细胞群考虑到F.肝片形吸虫是英国唯一的片形吸虫，我们的研究结果表明，在片形吸虫病流行的地区，这种寄生虫主要是二倍体。hepatica在隔离中存在，并表明三倍体可能只起源于自然群体，其中F.肝片吸虫及其姊妹种肝片吸虫（Fasciola lactica）通常发生。
Diploid (2n = 2x = 20) and triploid (2n = 3x = 30) Fasciola hepatica have been reported in the UK, and in Asia diploid, triploid and mixoploid (2x/3x) Fasciola spp. exist but there is little information to indicate how common triploidy is, particularly in UK fluke. Here the ploidy of 565 adult F. hepatica from 66 naturally infected British sheep and 150 adult F. hepatica from 35 naturally infected British cattle was determined. All 715 of these parasites were diploid, based on observation of 10 bivalent chromosomes and sperm (n = 335) or, since triploids are aspermic, sperm alone (n = 380). This constitutes the first extensive analysis of the ploidy of F. hepatica field isolates from Great Britain and shows that most F. hepatica isolated from cattle and sheep are diploid and have the capacity to sexually reproduce. These data suggest that triploidy, and by extension parthenogenesis, is rare or non-existent in wild British F. hepatica populations. Given that F. hepatica is the only species of Fasciola present in Britain our results indicate that the parasite is predominantly diploid in areas where F. hepatica exists in isolation and suggests that triploidy may only originate in natural populations where co-infection of F. hepatica and its sister species Fasciola gigantica commonly occurs.