SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain.
Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell'Università 10, 35020, Legnaro, PD, Italy.
Parasitol Res. 2020 Apr;119(4):1353-1362. doi: 10.1007/s00436-020-06642-2. Epub 2020 Mar 10.
Recent studies have revealed extensive genetic variations among Neospora caninum, a cyst-forming protozoan parasite that is one of the main causes of bovine abortion in the cattle industry worldwide. Previous genetic studies based on multilocus microsatellite genotyping (MLGs) of different Ibero-American populations showed a high genetic diversity. These studies provided clear clues of a predominant clonal propagation in cattle and population sub-structuring partially associated with geographical origin. Although, these reports were limited to a reduced number of countries. In this study, the N. caninum isolates from aborted bovine fetuses and stillbirths and a goat abortion from Northern Italy were investigated genetically using 9 microsatellite markers. Complete or nearly complete isolate profiles were obtained from 30 fetuses and stillbirths. An extensive genetic diversity was also found in this Italian N. caninum population. The study of genetic relationships among Italian MLGs using network (eBURST) and principal component analyses based on the allele-sharing coefficient (PCoA) showed different clonal subpopulations disseminated throughout Northern Italy without apparent segregation depending on the geographic origin, cattle breed, or time of collection. The presence of linkage disequilibrium supports a predominant clonal propagation of Italian N. caninum. In addition, most of Italian MLGs segregated from other global populations including Spain, Argentina, Mexico, Brazil, Germany, and Scotland, suggesting the existence of specific N. caninum subpopulations in the Northern Italy and different subpopulations of N. caninum circulating in Europe.
最近的研究揭示了刚地弓形虫（Neospora caninum）广泛的遗传变异，这种囊形成的原生动物寄生虫是全球牛养殖业中牛流产的主要原因之一。以前基于不同伊比利亚裔美拉尼西亚人群的多位点微卫星基因分型（MLGs）的遗传研究显示出高度的遗传多样性。这些研究提供了明确的线索，表明在牛中存在主要的无性繁殖和部分与地理起源相关的种群亚结构。尽管这些报告仅限于少数几个国家。在这项研究中，使用 9 个微卫星标记对来自意大利北部流产牛胎儿和死胎以及山羊流产的刚地弓形虫分离株进行了遗传研究。从 30 个胎儿和死胎中获得了完整或几乎完整的分离株图谱。在意大利的刚地弓形虫种群中也发现了广泛的遗传多样性。使用网络（eBURST）和基于等位基因共享系数（PCoA）的主成分分析研究意大利 MLGs 之间的遗传关系表明，不同的无性繁殖亚群在意大利北部传播，没有明显的地理起源、牛品种或采集时间的分离。连锁不平衡的存在支持意大利刚地弓形虫的主要无性繁殖。此外，意大利的大多数 MLGs 与包括西班牙、阿根廷、墨西哥、巴西、德国和苏格兰在内的其他全球种群分离，这表明意大利北部存在特定的刚地弓形虫亚群，而欧洲则存在不同的刚地弓形虫亚群。
