Funding for this research was provided by:
Department for Environment, Food and Rural Affairs (SE3122 and SB4500)
Article History
Received: 30 April 2018
Accepted: 24 August 2018
First Online: 4 September 2018
Ethics approval
: Not applicable.
: Not applicable.
: The authors completed this work as civil servants working for the Animal and Plant Health Agency, UK.
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