Monitoring trends and developments in cattle health using routinely collected census data

Authors: van Wuijckhuise L, Santman-Berends I, De Bont-Smolenaars AJG, van Schaik G, Brouwer-Middelesch H
Publication: Proceedings of the International Conference on Animal Health Surveillance, Volume 2017 Conference, pp 1-3, Apr 2017
Publisher: New Zealand Veterinary Association

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Abstract:

In the Netherlands, a national Cattle Health Surveillance System (CHSS) is in place that consists of several surveillance components including a quarterly data analysis component to monitor trends and developments in cattle health using routine census data called the Trend Analysis Surveillance Component (TASC). The challenges that were faced during the development of the TASC and the merits of this surveillance component are discussed to provide guidance to those who want to develop such a system. Challenges that had to be solved were subdivided into process-oriented challenges, e.g. data availability, confidentiality, etc. and analytical issues including data validation, aggregation and modeling. The results of TASC had to provide information on cattle health that was intuitive to the stakeholders and could support decision making. Key monitoring indicators that relate to cattle health were developed including parameters on mortality, fertility, udder health, milk production and antimicrobial usage. Population-Averaged Generalised Estimating Equations, with the appropriate distribution were used for analysis. Both trends in time and associations between cattle health indicators and potential confounders are monitored, discussed and reported to the stakeholders on a quarterly level. The TASC provides insight in cattle health parameters, it visualises trends in time, can be used to support or nuance signals that are detected in one of the other surveillance components, is sustainable and provide warnings or initiate changes in policy when unfavorable trends occur.

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