Worried that dog breeds popularized by celebrities, movies and television will become the targets of puppy mills, Canadian and U.S. kennel clubs are asking people to think seriously before buying one of the dogs as a pet. "Everybody wants a Dalmatian or a bearded collie or a Jack Russell after they see them in a movie," Patti Murray of Ashton, Ont., a member of both the Canadian and U.S. bearded collie clubs, said yesterday. "But these breeds are definitely not for everybody. They are a major commitment." Such pleas have been issued before by animal groups, especially since Disney's live-action...