You might find this link to a detailed submission to the New Zealand Government Select Committee looking at dog tail docking to be very useful to contructing similar arguments. It can also be found by checking the New Zealand Fish & Game Council website, under the Auckland Waikato region section. If there are questions that arise from this, please contact me.

http://most0010046.e-xpert.co.nz/Site/Regions/Auckland/huntingNews/Feb09.aspx