Seven-year-old Natalie Hall watched with delight Saturday as Roseburg police Officer Ryan Dingman sent his German shepherd police dog Iago after a pretend suspect dressed in protective clothing during a demonstration at the Sportsmen’s & Outdoor Recreation Show at the Douglas County Fairgrounds. “I like how he bit the man,” said a smiling Natalie, who lives in Roseburg. Dingman explained to an outdoor audience that numbered more than 100 that 5-year-old Iago thinks he is engaged in a game of tug of war whenever he’s called to subdue a suspect. “It’s pure fun for him,” Dingman said. “You’ll notice his …