There are exceptions to every breed--retrievers who won't retriever, pit bulls who wouldn't fight other dogs even if they were being eaten alive, dobermans who would happily show a thief where the silverware's kept--but LuckyRescue's right, in general
northern breeds are not good with cats. We have a local husky rescue that lists dogs on Petfinder and almost every one has the little "not good with cats" icon next to its name. Ditto with a local daschund rescue. (Daschunds were bred to hunt badgers.) That's not to say huskies, etc, are NEVER good with cats--some are, like your dog.
But a lot aren't.
Raising a puppy with a cat will generally make a dog more accepting of cats, no matter the breed--as long as it's never allowed to chase the cat to begin with. (It helps if the cat is willing to stand up to the pup and enforce its status with a well-aimed whack. But potentially dangerous, too, because cat scratches can cause infections.)
Even so, a dog who's perfectly fine with his own cats may try to chase and kill strange cats. It's instinct. And the dog finds it fun.
As Lucky said, do NOT introduce a cat and a dog outside the home . . . The cat will be doubly stressed, both by the strange territory and the presence of the dog.