Stirling Julie M, Eze Jude I, Foster Geoffrey, Reeves Aaron, Gunn George J, Tongue Sue C
Epidemiology Research Unit (Inverness), Department of Veterinary and Animal Science, Northern Faculty, Scotland's Rural College (SRUC), Scotland, United Kingdom.
Biomathematics and Statistics Scotland, JCMB, Edinburgh, United Kingdom.
Front Vet Sci. 2020 Apr 24;7:205. doi: 10.3389/fvets.2020.00205. eCollection 2020.
The design of surveillance strategies is often a compromise between science, feasibility, and available resources, especially when sampling is based at fixed locations, such as slaughter-houses. Advances in animal identification, movement recording and traceability should provide data that can facilitate the development, design and interpretation of surveillance activities. Here, for the first time since the introduction of electronic identification of sheep, the utility of a statutory sheep movement database to inform the design and interpretation of slaughter-house based surveillance activities has been investigated. Scottish sheep movement records for 2015-2018 were analyzed in combination with several other data sources. Patterns of off-farm movements of Scottish sheep to slaughter were described and the spatial distribution of several distinct slaughter populations, throughputs and catchment areas for Scottish slaughterhouses were determined. These were used to evaluate the coverage of a convenience-sample slaughter-house based survey for antimicrobial resistance (AMR). In addition, non-slaughter sheep movements within and between Scottish regions were described and inter-and intra-regional movement matrices were produced. There is potential at a number of levels for bias in spatially-associated factors for ovine surveillance activities based at Scottish slaughterhouses. The first is intrinsic because the slaughtered in Scotland population differs from the overall Scottish sheep slaughter population. Other levels will be survey-dependent and occur when the catchment area differs from the slaughtered in Scotland population and when the sampled sheep differ from the catchment area. These are both observed in the AMR survey. Furthermore, the Scottish non-slaughter sheep population is dynamic. Inter-regional movements vary seasonally, driven by the sheep calendar year, structure of the Scottish sheep industry and management practices. These sheep movement data provide a valuable resource for surveillance purposes, despite a number of challenges and limitations that were encountered. They can be used to identify and characterize the spatial origin of relevant populations and so inform the interpretation of existing slaughterhouse-based surveillance activities. They can be used to improve future design by exploring the feasibility and cost:benefit of alternative sampling strategies. Further development could also contribute to other surveillance activities, such as situational awareness and resource allocation, for the benefit of stakeholders.
监测策略的设计通常是在科学性、可行性和可用资源之间进行权衡，尤其是当采样基于固定地点（如屠宰场）时。动物识别、移动记录和可追溯性方面的进展应能提供有助于监测活动开展、设计和解读的数据。在此，自引入绵羊电子识别以来，首次对法定绵羊移动数据库用于指导基于屠宰场的监测活动的设计和解读的效用进行了调查。结合其他几个数据源，对2015 - 2018年苏格兰绵羊移动记录进行了分析。描述了苏格兰绵羊离开农场前往屠宰的移动模式，并确定了几个不同屠宰群体的空间分布、苏格兰屠宰场的产量和集水区。这些被用于评估基于便利样本屠宰场的抗菌药物耐药性（AMR）调查的覆盖范围。此外，还描述了苏格兰各地区内部和之间的非屠宰绵羊移动情况，并生成了区域间和区域内移动矩阵。基于苏格兰屠宰场的绵羊监测活动在空间相关因素方面存在多个层面的偏差可能性。第一个层面是内在的，因为在苏格兰屠宰的绵羊群体与整个苏格兰绵羊屠宰群体不同。其他层面将取决于调查情况，当集水区与在苏格兰屠宰的群体不同以及当采样绵羊与集水区不同时就会出现。这些在AMR调查中都有体现。此外，苏格兰非屠宰绵羊群体是动态的。区域间移动随季节变化，受绵羊历年、苏格兰绵羊产业结构和管理实践的驱动。尽管遇到了一些挑战和限制，但这些绵羊移动数据为监测目的提供了宝贵资源。它们可用于识别和描述相关群体的空间来源，从而为现有基于屠宰场的监测活动的解读提供信息。它们可用于通过探索替代采样策略的可行性和成本效益来改进未来设计。进一步的发展还可为其他监测活动（如态势感知和资源分配）做出贡献，以造福利益相关者。
