A Canadian cow from a ranch near Jenner, Alta., tested positive for tuberculosis at a packing plant in the United States.
That has led to quarantines covering about 30 southeastern Alberta ranches where the Canadian Food Inspection Agency and provincial officials are investigating.
"The investigation is ongoing and it is not yet known how many animals will require testing," said agency spokesman Denis Schryburt in an email to Canadian Press.
"The number of animals requiring testing will depend on a number of factors such as whether additional animals test positive and the movements of exposed animals to other locations."
He said the affected cow came from a ranch near Jenner, about 250 kilometres east of Calgary.
Canada is officially clear of tuberculosis. It’s not yet clear whether the U.S. will impose trade restrictions.