The Rottweiler (/ˈrɒtwaɪlər/, UK also /-vaɪlər/) is a breed of domestic dog, regarded as medium-to-large or large. The dogs were known in German as Rottweiler Metzgerhund, meaning Rottweil butchers' dogs, because their main use was to herd livestock and pull carts laden with butchered meat to market. This continued until the mid-19th century when railways replaced droving. During the First and Second World Wars, Rottweilers saw service in various roles, including as messenger, ambulance, draught, and guard dogs. The Fédération Cynologique Internationale gives the following description of the Rottweiler standard: 'Rottweiler breeders aim at a dog of abundant strength, black coated with clearly defined rich tan markings, whose powerful appearance does not lack nobility and which is exceptionally well suited to being a companion, service, rescue and working dog.' The Intelligence of Dogs, University of British Columbia, Vancouver.