The Canadian Food and Inspection Agency said the changes, effective immediately, mean that Russia will only accept meat imports from 19 Canadian plants, compared with about 60 that were approved prior to the new guidelines.
The revised list includes 15 pork plants, three beef and veal plants and one plant that processes both cattle and hogs. The CFIA says a number of storage facilities will also be permitted to ship meat to Russia.
The tougher restrictions are the latest to be imposed by Russia on Canada's use of the feed additive ractopamine in its livestock.
Ractopamine is given to animals to create lean meat, and has been banned in several countries including South Korea and Taiwan due to possible health concerns. Health Canada has approved it for safe human consumption.
In December, Russia announced it was banning any Canadian meats that contain the additive. Its new guidelines now only permit meat imports that are born from ractopamine-free animals and slaughtered at plants that do not use the food additive.
Russia is Canada's third-largest market for Canadian pork, with imports worth about $500 million last year.
Martin Charron, vice-president of Canadian Pork International, says officials from both governments are in discussions about getting more plants approved to export to Russia again.
Charron says the list, which goes into effect on April 17, may be based on outdated information. The marketing and promotion agency says Russian officials have not inspected Canadian plants for at least two years.
"We have establishments not on that list that are ractopamine-free," he said from Ottawa.
"When the Russians announced their intention to ban ractopamine in early December, many of our members decided to implement procedures to basically remove ractopamine from their production... The Russians basically looked at their file and established a list based on that."
The Canadian Cattlemen's Association has previously said that Canada abides by international guidelines on ractopamine use.
Last year, Canada imported $15 million of cattle products into Russia last year — with the majority being liver products.
The CFIA says talks between the two governments are ongoing.
"The government of Canada will continue to work with the Russian authorities in negotiating continued access for Canadian meat products," the agency said in an emailed statement.
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