A huge-headed, duck-footed mix of beagle, boxer and basset hound was the upset winner at the 25th annual World's Ugliest Dog Contest.

Walle, a four-year-old dog from Chico, California who was entered at the last minute, was judged most unsightly of 30 dogs at the Northern California competition.

"This dog looked like he's been photo-shopped with pieces from various dogs and maybe a few other animals," judge Brian Sobel said at the contest at the Sonoma-Marin Fairgrounds in Petaluma, north of San Francisco.

Walle overcame the dominance in recent years by nearly hairless Chihuahuas, Chinese cresteds, or combinations of the two.

Owner Tammie Barbee got the dog when he was three months old.

"People come up to me and say that dog is not right," Ms Barbee said, "but I love him."

Judges said they were especially impressed by Walle's bizarre waddle of a walk.

Walle wins 1,500 dollars and will make several network TV appearances next week, including NBC's "Today" show and ABC's "Jimmy Kimmel Live."

Organisers say the dogs are judged for their "natural ugliness in both pedigree and mutt classes".