Finland also made it two from two on the second day of competition thanks to a 4-1 victory over Hungary.
Elsewhere in the opening games across Switzerland, Austria dispatched Great Britain 5-2 in Group A, thanks, in part, to a lightning start.
Slovakia needed a late goal from Marek Hrivik to get their campaign off to the perfect start with a 2-1 victory over a stubborn Norway side to get Day Two underway.
Hosts Switzerland began their campaign with a 4-2 win over Latvia, while Slovenia edged past the Czech Republic 3-2 after overtime.
Canada hit Italy for six
After an opening day 5-3 win over Sweden, Canada backed it up to sweep Italy side, getting the scoring started early in Fribourg.
Dylan Holloway, Fraser Minten and captain Macklin Celebrini all scored in the first period to give the North Americans an early buffer, which they never relinquished.
Celebrini added another in the 23rd minute of play before Evan Bouchard netted the only power-play goal of the game.
Ryan O'Reilly finished up the thrashing at the end of the second period. Canada face tougher opposition next, when they take on Denmark in two days' time.
Finland continue good form in Hungary victory
Two goals from Jesse Puljujarvi saw Finland see off Hungary to keep their 100% record at this year's championships.
The Servette forward, familiar with his surroundings in Switzerland, netted his first to make it 2-0 after Ville Heinola had opened the scoring.
Hungary did make it a one-goal soon after through Balazs Sebok, but that would be their only glimmer of hope in the contest as Finland pulled away.
Janne Kuokkanen made it 3-1 with the fourth goal of the second period, before Puljujarvi took advantage of a power-play to round off the scoring with 17 minutes left in the game.
Slovaks labour to win
After a run to the bronze medal match at the Olympics earlier this year, Slovakia were considered a dark horse for this World Championships, and they had a great start to their 2026 opener, with Kometa Brno star Kristian Pospisil scoring inside nine minutes to give his side the lead over the Scandinavians.
But, a sluggish performance in the first and second period gave Norway confidence, as they matched their opponents shot-for-shot. Their reward came 13 seconds before the end of the second period as Tinus Koblar's shot fortunately slipped under the leg of goaltender Samuel Hlavaj.
Normal service was resumed midway through the final period of this tussle, as Hrivik turned one into the net to earn his side victory.
GB show fight despite Austria loss
After gaining promotion back to the World Championships, Great Britain were looking to build on their 2024 form, which saw them win one game despite relegation.
However, in the early going, they struggled to match their Austrian opponents, finding themselves 3-0 down inside the opening 10 minutes.
Benjamin Nissner, Peter Schneider and Paul Huber all scored in quick succession before Britain found their feet.
David Clements and talisman Liam Kirk made it a one-goal game at the end of the first period, only for Austria to forge ahead once more.
Two more goals came in the second period, another from Schneider and the fifth from Leon Wallner, allowing the central Europeans to take their foot off the gas in the final period of the encounter as they look ahead to sterner tests.