Using a novel, high welfare in vivo feeding device for poultry red mite and its integration with other novel tools for this parasite

无论采用何种产蛋系统，家禽红蜘蛛(PRM)对鸡舍的侵扰都是全球蛋业面临的重大动物福利和经济问题。PRM对蛋鸡的影响主要有两个方面：一是螨虫叮咬禽类并以其血液为食引起刺激和贫血的直接影响；二是螨类传播疾病给蛋鸡造成的间接影响。传统的在鸡舍里喷洒化学物质来控制PRM的方法现在已经失败了，因为这些螨类对这些化学物质产生了抗药性。因此，对控制PRM的新方法的需求很高，世界各地的几个研究小组正在研究这些新的控制方法。通常，新控制方法的测试最初在实验室测试中使用螨类，然后使用大量母鸡进行田间测试。例如，控制PRM的疫苗的开发通常使用初步的实验室筛选测试来确定潜在的疫苗，然后进入田间试验，每次试验可以使用多达800只母鸡，持续几个月。这一策略有两个主要缺陷：1)基于实验室的分析结果高度可变，可能无法准确预测田间试验中会发生什么；2)田间试验涉及大量持续暴露于寄生虫的禽类。为了解决这些问题，我们开发了一种‘on-Heen’蠕虫喂食器，作为基于实验室的测试的替代方案，它允许在进行田间研究之前，对少量母鸡的疫苗和其他螨类控制方法进行更准确的评估。这一战略解决了3Rs原则的“减少”方面，大大减少了母鸡的使用数量，因为它将在疫苗或其他控制方法(例如新杀虫剂)进入田间试验之前准确地识别出表现不佳的疫苗或其他控制方法。该系统还可用于在不使禽类持续暴露于寄生虫的情况下，在较小数量的母鸡(每个处理组4只，而田间试验中每个处理组400只)上测试较长时间的螨类控制方法的有效性。因此，这解决了第二个3RS原则--“精细化”，因为它允许鸟类在试验期的绝大多数时间里不受寄生虫的侵袭，寄生虫每3周只接触鸟类一小段时间(3小时)，而不是在野外试验中遇到的持续暴露。我们已经通过成本行动流动赠款成功地将这项技术转让给了西班牙卡斯蒂利亚-拉曼查大学的一个疫苗开发小组，现在我们希望举办一个为期3天的研讨会，通过实际演示和讨论来传播这项技术，讨论它如何与其他新颖和新兴的PRM研究工具交叉，以促进其在整个欧洲的实验室采用。拟参加研讨会的人员感兴趣的是改进和减少母鸡在开发包括杀虫剂、驱虫剂和疫苗在内的新干预措施方面的使用，以及调查PRM传播疾病的能力。这项提议的主要目的是在莫雷登研究所举办一个研讨会：1)展示优化系统的构建和使用，以便科学家在进入大规模田间试验之前，使用精确、轻度和增强的新疫苗和杀虫剂预筛选来控制吸血寄生虫，以及；2)演示和讨论如何将这项新技术与该领域的其他新兴技术相结合。每个选定的参与者都是更大网络的成员，具有开发这些技术的潜力，而这些技术超出了最初的研讨会的范围。

Infestation of hen houses with poultry red mites (PRM) is a major animal welfare and economic problem for the egg industry worldwide, irrespective of the type of laying systems employed. The two main impacts of PRM on laying hens are direct effects of the mites biting the birds and feeding on their blood which causes irritation and anaemia, and indirect effects caused by the mites transmitting diseases to the hens. Traditional methods of controlling PRM with chemical sprays in hen houses are now failing as the mites become resistant to the chemicals. Demand for novel methods of controlling PRM is therefore high and several research groups around the world are working on these new methods of control. Typically, the testing of novel control methods uses mites in laboratory-based tests initially, followed by field testing using large numbers of hens. For example, the development of vaccines to control PRM routinely uses initial laboratory-screening tests to identify potential vaccines before moving into field trials which can use up to 800 hens in each trial and last for several months. This strategy has 2 major drawbacks:1) Results from the laboratory-based analyses are highly variable and may not accurately predict what happens in field trials;2) Field trials involve large numbers of birds continually exposed to parasites for prolonged periods.To address these issues we have developed an 'on-hen' mite feeding device, as an alternative to the laboratory-based tests, which allows much more accurate assessment of vaccines and other mite control methods on small numbers of hens before field studies are conducted. This strategy addresses the "Reduction" aspect of the 3Rs principles by greatly reducing the number of hens used, as it would accurately identify poorly performing vaccines or other control methods (e.g. new pesticides) before they were progressed to field trials. This on-hen system can also be used to test the effectiveness of mite control methods across prolonged periods on small numbers of hens (4 per treatment group, as opposed to 400 per treatment group in field trials) without continually exposing birds to the parasites. This therefore addresses a second 3Rs principle - "Refinement" as it allows the birds to remain free from the parasites for the vast majority of the experimental period, with parasites only accessing the birds for short (3 hour) periods every 3 weeks instead of the continual exposure encountered in field trials. We have successfully transferred this technology to a vaccine-development group at University of Castilla-La Mancha, Spain through a COST Action mobility grant and we now wish to hold a 3-day workshop to disseminate this technology with practical demonstrations and discussions around how it intersects with other novel and emerging tools for PRM research to promote its adoption in laboratories across Europe. The proposed participants in the workshop have interests in both refinement and reduction of the use of hens in the development of novel interventions including pesticides, repellents and vaccines and in investigations of the ability of PRM to spread disease. The principal aims of this proposal are to hold a workshop at Moredun Research Institute to:1) Demonstrate the construction and use of an optimised system for scientists to use in an accurate, mild-severity and enhanced pre-screening of new vaccines and pesticides for the control of a blood-feeding parasite before progressing to large field trials, and;2) Demonstrate and discuss how this novel technology may be integrated with other emerging technologies in this field.Each of the selected participants is a member of larger networks with the potential to exploit these technologies beyond the reach of this initial workshop.