Unravelling the aetiology of contagious ovine digital dermatitis.

揭示传染性羊指皮炎的病因。

• 批准号: BB/N002121/1
• 负责人: Nicholas Evans
• 金额: $ 50.17万
• 依托单位: University of Liverpool
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FN002121%2F1
• 关键词: Unravelling; aetiology; contagious; ovine; digital

Contagious ovine digital dermatitis (CODD) is an extremely severe and relatively recent cause of infectious lameness in sheep in the UK, affecting approximately 35-53% of UK sheep farms and 300,000 sheep annually. The economic impact of CODD is unknown but likely similar to that of footrot, another common cause of lameness which is estimated at £24million per year. The Farm Animal Welfare Council, who report to the UK government on farm animal welfare issues, identified that research into this new disease should be a priority. Research into footrot has led to substantial improvements for the evidenced based advice available to farmers and vets on this aspect of lameness, and has been widely taken up by the sheep industry. However many farmers are struggling to control CODD infection in their flocks and substantial research support is required here. The applicants are currently the only research group studying CODD and through funding from the British Veterinary Association, HCC and EBLEX, this research group is making advances in our understanding of the epidemiology, pathology and microbiology of the disease, including the development of control strategies using antimicrobial drugs. The outputs of this work will produce practical solutions for the farming industry. Given the severe pressure on antimicrobial usage world-wide, sustainable, non-antibiotic solutions to CODD must focus on preventative approaches such as stopping the introduction of disease into naïve flocks through biosecurity and improvement in the sheep's ability to resist infection through vaccination. Both these solutions require a greater knowledge of the agent(s) causing the disease than we currently possess. We have already demonstrated evidence that specific culturable treponemes identical to those from bovine digital dermatitis have an association with CODD lesions and data from other studies has suggested a role for Dichelobacter nodosus and Fusobacterium necrophorum. This study proposes to i) carry out substantial metagenomic (entire microbial community) investigations of CODD lesions to identify the key microbes involved and ii)to characterise the host immune response to the identified microbes and determine whether specific antigens may allow a protective immune response to underpin future vaccine studies and iii) to use additional metagenomic surveys of the host farm environment and faeces to detect the relevant microbes which should allow for relevant farmer / veterinary guidelines to improve disease control.This proposal would ensure we obtain a greater understanding of the role of different bacteria in CODD development. This information will be key to future vaccine studies so that the correct microorganisms are targeted for vaccine design. Monitoring specific immunity in the naive sheep flock to be used in this study after exposure to CODD will allow assessment of the different stages of the infective process. This will not only describe stages of microbial infections but may also identify whether some animals are able to produce an effective immune response allowing for subsequent antigen discovery for effective vaccines. Identification of the considered causal microorganisms will also allow for more appropriate antimicrobial treatments thus reducing the risk of antibiotic resistance developing. Monitoring bacterial populations of CODD lesions post treatment should inform biosecurity practices i.e. whether treated animals result in bacteriological cure or become asymptomatic CODD "carriers". Monitoring faeces and environmental samples prior and post antibiotic treatment will also allow for development of best farm practices to minimise reinfection of sheep with CODD thus preventing failure / overuse of antibiotic treatment at the flock level.Investigating CODD using the various methods described above, should improve understanding of the disease and contribute towards the eradication of this painful and expensive disease.

传染性绵羊数字皮炎(Codd)是英国绵羊传染性跛行的一种极其严重和相对较新的原因，每年影响大约35%-53%的英国养羊场和30万只绵羊。鳕鱼的经济影响尚不清楚，但很可能类似于脚踏，另一种常见的跛行原因估计为每年2400万英镑。农场动物福利委员会向英国政府报告农场动物福利问题，认为对这种新疾病的研究应该是优先事项。对脚步的研究已经大大改善了农民和兽医在这方面可获得的基于证据的建议，并已被羊业广泛采用。然而，许多农民正在努力控制他们羊群中的鳕鱼感染，这方面需要大量的研究支持。申请者目前是研究Codd的唯一研究小组，通过英国兽医协会、肝细胞癌和EBLEX的资助，该研究小组在我们对该病的流行病学、病理学和微生物学的了解方面取得了进展，包括制定使用抗微生物药物的控制策略。这项工作的成果将为农业提出切实可行的解决方案。鉴于世界范围内抗菌剂使用面临的严重压力，可持续的非抗生素解决方案必须侧重于预防性方法，例如通过生物安全阻止疾病进入幼稚的羊群，以及通过接种疫苗提高绵羊抵抗感染的能力。这两种解决方案都需要比我们目前拥有的更多关于导致疾病的病原体(S)的知识。我们已经证明了与牛指状皮炎相同的特定可培养密螺旋体与Codd皮损有关，来自其他研究的数据表明结节双歧杆菌和坏死梭杆菌也有作用。这项研究建议i)对Codd病变进行大量的元基因组(整个微生物群落)调查，以确定涉及的关键微生物，ii)表征宿主对已识别微生物的免疫反应，并确定特定抗原是否可以实现保护性免疫反应，以支持未来的疫苗研究，以及iii)使用对宿主农场环境和粪便的额外元基因组调查来检测相关微生物，这将使相关的农民/兽医指南能够改善疾病控制。这项建议将确保我们更好地了解不同细菌在Codd发展中的作用。这些信息将是未来疫苗研究的关键，以便将正确的微生物作为疫苗设计的目标。监测暴露在Codd中的幼稚羊群中的特定免疫力将有助于评估感染过程的不同阶段。这不仅将描述微生物感染的各个阶段，还可能确定一些动物是否能够产生有效的免疫反应，从而为随后发现有效疫苗的抗原提供依据。鉴定被考虑的致病微生物还将允许进行更适当的抗微生物治疗，从而降低产生抗生素耐药性的风险。监测治疗后Codd病变的细菌种群应告知生物安全实践，即治疗动物是否导致细菌学治愈或成为无症状的Codd“携带者”。在抗生素治疗前后监测粪便和环境样本也将有助于制定最佳的养殖场做法，以最大限度地减少绵羊感染Codd的再次感染，从而防止在羊群层面上未能/过度使用抗生素治疗。使用上述各种方法调查Codd，应有助于提高对这种疾病的了解，并有助于根除这种痛苦和昂贵的疾病。

项目成果

Additional file 4 of The dysbiosis of ovine foot microbiome during the development and treatment of contagious ovine digital dermatitis

传染性羊指皮炎发生和治疗过程中羊足部微生物群失调的附加文件4

• DOI: 10.6084/m9.figshare.14053666
• 发表时间: 2021
• 作者: Duncan J

Additional file 2 of The dysbiosis of ovine foot microbiome during the development and treatment of contagious ovine digital dermatitis

传染性羊指皮炎发生和治疗过程中羊足部微生物群失调的附加文件2

• DOI: 10.6084/m9.figshare.14053660
• 发表时间: 2021
• 作者: Duncan J

Additional file 1 of The dysbiosis of ovine foot microbiome during the development and treatment of contagious ovine digital dermatitis

传染性羊指皮炎发生和治疗过程中羊足部微生物群失调的附加文件1

• DOI: 10.6084/m9.figshare.14053657
• 发表时间: 2021
• 作者: Duncan J

Contagious ovine digital dermatitis (CODD) - where are we now?

传染性绵羊指皮炎（CODD）——我们现在在哪里？

• 发表时间: 2017
• 期刊: CATTLE PRACTICE
• 影响因子: 0.3
• 作者: Angell J. W.

The Dysbiosis of Ovine Foot Microbiome During the Development and Treatment of Contagious Ovine Digital Dermatitis

传染性羊指皮炎发生和治疗过程中羊足部微生物群的失调

• DOI: 10.21203/rs.3.rs-96268/v1
• 发表时间: 2020
• 作者: Duncan J