A screen grab from the Mercy For Animals Canada video.

WINNIPEG - Editor's note: The embedded video is graphic in nature. Viewers' discretion is advised.

An animal rights group is demanding major grocers stop buying meat from hog farms that mistreat pigs.

Twyla Francois, investigations director for Mercy For Animals Canada, made the demand at a press conference in Winnipeg after showing a secretly shot video of the way pigs were treated at a Puratone Corp., farm near Arborg, Man., this past summer.