Effect of Nematode and Mycobacterium avium subspecies paratuberculosis Infections on the Ovine Intestinal Microbiome

线虫和鸟分枝杆菌副结核亚种感染对绵羊肠道微生物组的影响

• 批准号: 2609719
• 金额: --
• 依托单位: University of Edinburgh
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2609719
• 关键词: Effect; Nematode; Mycobacterium; avium; subspecies

Disease in the agricultural industry is a problem for farmers as it negatively impacts their income as well as reducing the welfare of their livestock. Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of Johne's disease in sheep and found in other economically relevant ruminants such as cattle and goats. The disease is characterised by emaciation as a result of thickening of the intestinal wall, reducing nutrient absorption and causing the animal to starve despite appearing to eat normally. MAP is also known to co-occur with parasitic nematode worms such as Teladorsagia circumcincta and Oesophagostomum columbianum which can have a synergistic or mechanical vectoring effect on the disease. Farmers face many challenges when trying to control MAP or prevent it from entering their flocks. MAP is transmitted via the faecal-oral route and shed from infected animals in faeces to the surrounding environment where it can survive for over a year. Transmission may also occur via wildlife reservoirs including wild deer, foxes and rabbits. Sheep will often become infected with MAP in their first few months of life either from faecally-contaminated soils, water, surfaces or shedding from their mother's milk. This infection can go undetected as many cases are sub-clinical; problems with diagnostic testing can also lead to Johne's disease being under-diagnosed. MAP is also controversially associated with Crohn's disease in humans and so represents a potential public health threat. Preliminary studies carried out by our group have shown that treating sheep with anthelmintic leads to changes in the intestinal microbiota, specifically that an unresolved nematode infection leads to reduced levels of the potentially-beneficial Actinobacteria. In other work leading up to this project, faecal samples have been collected from a flock of farm-raised sheep in Angus with co-occurring nematode and MAP infections over a three-year period, providing a longitudinal profile of the changes in the microbiota within individual sheep and the flock as a whole. These baseline data will form the reference against which the effects of worm treatment and vaccination against Johne's disease will be assessed. By studying the fluctuations in the intestinal microbiota, the effect of anthelmintic treatment on the efficacy of vaccination against MAP in farm-raised sheep will be investigated.The project will aim to:Characterise the prokaryotic component of the gut microbiota in a farm-raised sheep flock using metataxonomic DNA sequencing. Investigate the persistence of MAP in soils at different locations on the study farm using qPCR and culture techniques, and link this to soil conditions, other soil microbiota and disease in the sheep which graze these areas.Investigate the relationship between MAP infection, parasitic worm infection and intestinal microbiota in a farm-raised sheep flock. Assess vaccine efficacy against Johne's disease using diagnostic testing and microbiota profiling. Evaluate the impact of anthelmintic treatments on vaccine efficacy.This information will be used as a basis for improving diagnostic and treatment strategies for MAP and nematode infection to improve animal health and welfare. (492)

农业产业的疾病是农民的一个问题，因为它会对他们的收入产生负面影响，并减少牲畜的福利。分枝杆菌鸟类亚种结核病（MAP）是绵羊约翰氏病的病原体，在其他经济相关的反刍动物（例如牛和山羊）中发现。该疾病的特征是由于肠壁增厚，减少营养吸收并导致动物饿死，尽管似乎正常食用，但该疾病的特征是。也已知MAP与寄生线虫蠕虫（例如Teladorsagia crancincta和Oesophopostomum columbianum）共同发生，这些蠕虫可能对疾病具有协同或机械的矢量效应。农民试图控制地图或防止其进入羊群时面临许多挑战。 MAP通过粪便口径传播，并从粪便中的感染动物脱落到周围环境，在周围环境可以生存一年多。传播也可能通过野生动植物的水库进行，包括野鹿，狐狸和兔子。绵羊通常会在生命的头几个月中被藏料感染。这种感染可能未被发现，因为许多情况下是次临床。诊断测试的问题也可能导致约翰病的诊断不足。 MAP在人类中也与克罗恩病有关，因此代表了潜在的公共卫生威胁。我们小组进行的初步研究表明，用驱虫治疗绵羊会导致肠道微生物群的变化，特别是未解决的线虫感染会导致潜在的潜在浅性阳离状细菌的水平降低。在该项目的其他工作中，已经从安格斯（Angus）的一群农场饲养的绵羊中收集了粪便样品，并在三年的时间内与同时存在的线虫和地图感染收集，从而提供了单个绵羊内微生物群的变化的纵向形象，整个绵羊和整个羊群。这些基线数据将构成参考，该参考将评估蠕虫治疗和疫苗接种对约翰病的影响。通过研究肠道菌群中的波动，将研究驱虫治疗对疫苗接种在农场饲养的绵羊中疫苗接种功效的影响。该项目的目的是：表征肠道菌群的原核生物成分在农场饲养的绵羊羊群中，使用带动型DNA序列化。使用QPCR和培养技术研究了研究农场不同位置的土壤中MAP的持续性，并将其与绵羊的土壤条件，其他土壤微生物群和疾病联系起来，这些区域将这些区域放牧。对寄生虫感染，寄生虫感染和农场饲养的羊群的肠道感染之间的关系。使用诊断测试和菌群分析评估针对Johne病的疫苗功效。评估驱虫治疗对疫苗功效的影响。该信息将用作改善地图和线虫感染的诊断和治疗策略的基础，以改善动物健康和福利。 （492）