The World Trade Organization has given the US until 23 May 2013 to bring its Mandatory Country of Origin Labelling law into compliance with WTO rules or face the prospects of retaliatory tariffs on US products exported into Canada and Mexico.

A report prepared for the Canadian Pork Council shows since its October 2008 introduction M-COOL has disrupted the movement of almost 20 million Canadian pigs costing Canadian pork producers almost two billion dollars by the end of 2012.

The report's author, Alberta Agriculture and Rural Development pork specialist Ron Gietz says the information will be used by the federal government to set retaliatory tariffs in the event the issue isn't resolved by the WTO deadline.

Ron Gietz-Alberta Agriculture and Rural Development

We basically looked at the official US Commerce Department data and that will give you monthly quantities and volumes and it also breaks it down for all the different categories but the three categories where we saw sharp declines in trade and therefore where we calculated the damages were the slaughter hogs, the under seven kilogram feeder pigs, also known as isoweans and then the greater than 23 kilogram, less than 50 kilogram feeder pigs and we also did an analysis on the impact on the pork trade itself.

Pork was impacted because, if you talk to the Canadian packers, they no longer have ready access to the US retail market because of those labelling restrictions as well.

Mr Gietz notes his study looked at injury to the Canadian pork industry specifically so there's also impacts on the Canadian cattle industry and other Canadian livestock industries and on Mexico.