Doctor Quacker is a male dognose.
Doctor Quacker is a Duckburg-based physician. In 1959, Gyro Gearloose consulted him (on behalf of both himself and Scrooge McDuck, who shared his symptoms) about a sickness he had in his throat. Though Quacker initially, correctly identified this as an effect of working day in day out exposed to the Duckburg smog, he then mistakenly heard the Little Helper's buzzing in place of Gyro's heartbeat, and concluded that Gyro was suffering from a fatal cardiac disease known as “Puckeritis of the Pipelines“. Knowing no other cure, he sent Gyro (and, by extension, Scrooge) off to the countryside on holiday, thus kickstarting a series of comedic hijinks as the two tried and failed to crack this “having fun” thing they'd been hearing so much about.