Martinez-Ibeas Ana Maria, Munita Maria Pia, Lawlor Kim, Sekiya Mary, Mulcahy Grace, Sayers Riona
Animal and Biosciences Department, Animal & Grassland Research and Innovation Centre, Teagasc, Moorepark, Fermoy, Co. Cork, Ireland.
School of Veterinary Medicine UCD, Belfield, Dublin, Ireland.
BMC Vet Res. 2016 Jul 18;12(1):143. doi: 10.1186/s12917-016-0770-0.
Rumen flukes are trematode parasites found globally; in tropical and sub-tropical climates, infection can result in paramphistomosis, which can have a deleterious impact on livestock. In Europe, rumen fluke is not regarded as a clinically significant parasite, recently however, the prevalence of rumen fluke has sharply increased and several outbreaks of clinical paramphistomosis have been reported. Gaining a better understanding of rumen fluke transmission and identification of risk factors is crucial to improve the control of this parasitic disease. In this regard, a national prevalence study of rumen fluke infection and an investigation of associated risk factors were conducted in Irish sheep flocks between November 2014 and January 2015. In addition, a molecular identification of the rumen fluke species present in Ireland was carried out using an isolation method of individual eggs from faecal material coupled with a PCR. After the DNA extraction of 54 individual eggs, the nuclear fragment ITS-2 was amplified and sequenced using the same primers.
An apparent herd prevalence of 77.3 % was determined. Several risk factors were identified including type of pasture grazed, regional variation, and sharing of the paddocks with other livestock species. A novel relationship between the Suffolk breed and higher FEC was reported for the first time. The predominant rumen fluke species found was C. daubneyi. Nevertheless, P. leydeni was unexpectedly identified infecting sheep in Ireland for the first time.
An exceptionally high prevalence of rumen fluke among Irish sheep flocks has been highlighted in this study and a more thorough investigation is necessary to analyse its economic impact. The isolation of individual eggs coupled with the PCR technique used here has proven a reliable tool for discrimination of Paramphistomum spp. This technique may facilitate forthcoming studies of the effects of paramphistomosis on livestock production. The most noteworthy finding was the identification of P. leydeni affecting sheep in Ireland, however further studies are required to clarify its implications. Also, a significant relationship between Suffolk breed and a heavier infection was found, which can be used as a starting point for future research on control strategies of rumen fluke infection.
瘤胃吸虫是一种在全球范围内均有发现的吸虫类寄生虫；在热带和亚热带气候地区，感染可导致双口吸虫病，这会对家畜产生有害影响。在欧洲，瘤胃吸虫并不被视为具有临床意义的寄生虫，然而，最近瘤胃吸虫的流行率急剧上升，并且已报告了几起临床双口吸虫病的暴发。更好地了解瘤胃吸虫的传播并确定风险因素对于改善这种寄生虫病的控制至关重要。在这方面，于2014年11月至2015年1月期间在爱尔兰羊群中开展了一项瘤胃吸虫感染的全国流行率研究以及相关风险因素的调查。此外，采用从粪便材料中分离单个虫卵并结合PCR的方法，对爱尔兰存在的瘤胃吸虫种类进行了分子鉴定。在对54个单个虫卵进行DNA提取后，使用相同引物对核片段ITS-2进行扩增和测序。
确定明显的群体流行率为77.3%。确定了几个风险因素，包括所放牧牧场的类型、地区差异以及与其他家畜物种共用牧场。首次报道了萨福克品种与较高粪便虫卵计数之间的新关系。发现的主要瘤胃吸虫种类是道氏双口吸虫。然而，首次意外地在爱尔兰发现莱氏双口吸虫感染绵羊。
本研究突出了爱尔兰羊群中瘤胃吸虫的异常高流行率，有必要进行更深入的调查以分析其经济影响。这里使用的单个虫卵分离结合PCR技术已被证明是区分双口吸虫属物种的可靠工具。该技术可能有助于今后对双口吸虫病对家畜生产影响的研究。最值得注意的发现是在爱尔兰发现莱氏双口吸虫感染绵羊，然而需要进一步研究以阐明其影响。此外，发现萨福克品种与更严重感染之间存在显著关系，这可作为未来瘤胃吸虫感染控制策略研究的起点。
