The dog attacked the unidentified infant in the city north of Calgary at 10 a.m., and the child was pronounced dead of trauma at the Alberta Children's Hospital a half hour later, the Calgary Sun reported.
RCMP Sgt. Patricia Neely told reporters no charges are being considered against the parents.
The family has other children, but the dog has never threatened them, nor did it have any history of attacks, the National Post said.
"As far as the exact details of the attack, in deference to the family we're not giving a lot of information on exactly what occurred," Neely said. "Obviously, a baby isn't provoking an attack in any manner."
The dog was taken into quarantine. Whether it will be destroyed or adopted out is up to the family and Airdrie bylaw officers, the Sun said.