The Alaskan Malamute (/ˈmæləˌmjuːt/) is a large breed of domestic dog (Canis lupus familiaris) originally bred for their strength and endurance to haul heavy freight as a sled dog. They are similar to other arctic, husky, and spitz breeds such as the Greenland Dog, Canadian Eskimo Dog, the Siberian Husky, and the Samoyed. The eyes of the Alaskan Malamute are almond-shaped and are varied shades of brown; however, the darker eye is preferred. Purebred Alaskan Malamutes will not have blue eyes. The physical build of the Malamute is compact and strong with substance, bone and snowshoe feet. The most commonly reported health problems of Alaskan Malamutes, in the 2004 UK Kennel Club survey (based on a sample size of 64 dogs) were musculoskeletal (hip dysplasia), and hereditary cataracts. There are additional health issues in the breed whose origins are unknown at this time including varied seizure disorders found in young puppies as well as adults, epilepsy, congenital heart problems, kidney problems and skin disorders.