The dog's death Friday sparked public warnings to dog owners in Burnaby, east of Vancouver, to keep their pets on a leash and try to prevent them from picking up anything with their mouths, CTV News reported Monday.
The dog was one of two French mastiffs being walked in a park by owner Jamie Walton. The male dog, named Jada, became very sick and started choking soon after getting home, and Walton rushed it to a veterinarian.
The animal died 90 minutes later, and the unidentified veterinarian called the Royal Canadian Mounted Police, CTV News said.
"It is believed that the dog may have picked up a stick while in the park and been poisoned by a substance on the stick," RCMP Cpl. Alexandra Mulvihill told the broadcaster.
In June in Toronto, two dogs died and four others became sick after someone scattered poisoned pieces of bread in an off-leash area of a large park. No one has been charged in connection with that incident.