Combining molecular biology and computer modelling to enhance control of liver fluke in livestock across agricultural landscapes

结合分子生物学和计算机建模，加强对农业领域牲畜肝吸虫的控制

• 批准号: 2750173
• 金额: --
• 依托单位: Aberystwyth University
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2750173
• 关键词: Combining; molecular; biology; computer; modelling

Liver fluke (Fasciola hepatica) is a highly pathogenic trematode parasite that is highly prevalent in cattle and sheep globally, with its disease, fasciolosis estimated to cost European livestock producers over £2 billion annually. Climate change and anthelmintic resistance are driving increasing liver fluke prevalence globally. This increase in prevalence is seriously impacting animal health, welfare and productivity, and threatening the sustainability of livestock production in certain regions.To alleviate this threat, and to sustainably manage liver fluke in future decades, alternative non-chemical control strategies are required. These alternative strategies may target the F. hepatica lifecycle, which revolves around an intermediate snail host (Galba truncatula). This snail is only present in areas on pastureland where optimal environmental and microclimatic conditions allow it to thrive. Strategies including grazing rotation, temporary or permanent fencing of risk areas and targeted treatment of livestock to reduce pasture contamination of F. hepatica eggs can impede the lifecycle. However, major barriers prevent the mass adoption of these alternative control strategies. Poor understanding of the spatial distribution G. truncatula habitats on farms impedes on the ability of farmers to successfully apply measures targeting the snail. There is also limited information regarding how these alternative strategies can be optimally applied, including which periods of the year they should be employed and for how long.In recent years, the project's supervisory team have developed novel research tools that allow researchers to investigate the epidemiology of G. truncatula and F. hepatica at field level. These include the development of environmental DNA assays which can identify the presence of G. truncatula on farmland (Jones et al., 2018), and mechanistic modelling techniques which can accurately model F. hepatica infection risk over time at farm level (Beltrame et al., 2018). This project aims to utilise these tools to develop and evaluate farm specific guidance for successful application of non-chemical control methods for F. hepatica control on UK farms.During the PhD programme, the prospective student will evaluate and compare a range of DNA extraction methods and molecular tools to identify optimal methodology for G. truncatula eDNA capture, extraction and amplification. The optimal methodologies identified will then be applied to survey G. truncatula habitats on multiple UK farms. Environmental and climatic measurements will also be gathered in these sampling sites and analysed in conjunction with eDNA survey results to identify factors associated with the presence of G. truncatula snails in water-saturated habitats on farmland. Finally, mechanistic models will evaluate the impact of grazing rotations, temporary and permanent fencing of G. truncatula habitats and targeted treatment to minimise pasture contamination of fluke eggs on future F. hepatica infection risk in grazing livestock on farms studied and mapped via eDNA survey. These models will also evaluate the optimal timeframe for the application of these strategies, how weather interacts with farm topography and structure to affect their success, and how pasture architecture can be altered to enhance impact of grazing-based control, for fluke and co-infecting nematode parasites.The prospective student will acquire inter-disciplinary skills in molecular biology, parasitology, computational modelling and generic research methods and communication. Specifically, the prospective student will develop skills to perform a range of DNA extraction and amplification methodologies, to morphologically identify intermediate snail host and parasite life stages and to develop and apply mechanistic models. Training will be provided by the supervisory team and by Aberystwyth University's Graduate School Doctoral Training Programme.

肝氟（fasciola hepatica）是一种高度致病的巨寄生虫，在全球牛和绵羊中高度普遍，其疾病，筋膜病估计每年使欧洲牲畜生产者每年造成欧洲牲畜生产者的损失超过20亿英镑。气候变化和驱虫阻力正在推动全球肝氟氟化物的患病率增加。这种患病率的增加正在严重影响动物的健康，福利和生产力，并威胁到某些地区牲畜生产的可持续性。为了减轻这种威胁，并在未来几十年中可持续地管理肝氟，需要另类的非化学控制策略。这些替代性策略可能针对肝癌生命周期，该生命周期围绕中间蜗牛宿主（Galba Truncatula）。这种Snapil仅存在于牧场上最佳环境和微气候条件的地区。包括旋转旋转的策略，风险区域的临时或永久围栏以及对牲畜的靶向治疗，以减少肝卵的牧场污染，可能会阻碍生命周期。但是，主要的障碍阻止了这些替代控制策略的大规模采用。对农场上的空间分布G. truncatula栖息地的了解不足阻碍了农民成功采取针对Snapil的措施的能力。关于如何最佳应用这些替代策略的信息也有限，包括应该使用这些策略的一年，以及近年来，该项目的监督团队开发了新的研究工具，使研究人员可以研究G. truncatula和F. hepatica在现场水平上的流行病学。其中包括开发环境DNA分析，可以鉴定农田上G. truncatula的存在（Jones等，2018）以及机械建模技术，这些技术可以准确地模拟F. hepatica感染随着时间的流逝而在农场水平上的风险（Beltrame等，2018）。该项目旨在利用这些工具来开发和评估农场的特定指南，以成功地应用非化学控制方法，用于在英国农场进行肝。然后，确定的最佳方法将应用于多个英国农场的G. truncatula栖息地。环境和气候测量还将在这些抽样地点中收集，并与EDNA调查结果进行分析，以确定与农田中水饱和栖息地中G. truncatula蜗牛存在相关的因素。最后，机械模型将评估旋转旋转，G. truncatula栖息地的暂时和永久围栏的影响以及靶向治疗的影响，以最大程度地减少Fluke Egg的牧草污染对未来F. hepatica感染的风险在农场饲养牲畜上的hepatica感染风险，并通过EDNA调查绘制。 These models will also evaluate the optimal timeframe for the application of these strategies, how weather interacts with farm topography and structure to affect their success, and how pasture architecture can be altered to enhance impact of Grazing-based control, for fluke and co-infecting nematode parasites.The prospective student will acquire inter-disciplinary skills in molecular biology, parasiticology, computational modelling and generic research methods and communication.具体而言，准学生将发展技能，以执行一系列DNA提取和放大方法，以形态学识别中间蜗牛宿主和寄生虫生命阶段，并开发和应用机械模型。培训将由监督团队和Aberystwyth大学的研究生院博士培训计划提供。