Dogs have lived and worked with humans in so many roles that they have earned the unique nickname, "man's best friend",[61] a phrase used in other languages as well. They have been bred for herding livestock,[62] hunting (e.g. pointers and hounds),[63] rodent control,[3] guarding, helping fishermen with nets, detection dogs, and pulling loads, in addition to their roles as companions.[3] Book of the Hunt, Gaston III, Count of Foix, 138788. Service dogs such as guide dogs, utility dogs, assistance dogs, hearing dogs, and psychological therapy dogs provide assistance to individuals with physical or mental disabilities.[64][65] Some dogs owned by epileptics have been shown to alert their handler when the handler shows signs of an impending seizure, sometimes well in advance of onset, allowing the owner to seek safety, medication, or medical care.[66] Dogs included in human activities in terms of helping out humans are usually called working dogs. Dogs of several breeds are considered working dogs. Some working dog breeds include Akita, Alaskan Malamute, Anatolian Shepherd Dog, Bernese Mountain Dog, Black Russian Terrier, Boxer, Bullmastiff, Doberman Pinscher, Dogue de Bordeaux, German Pinscher, German Shepherd,[67] Giant Schnauzer, Great Dane, Great Pyrenees, Great Swiss Mountain Dog, Komondor, Kuvasz, Mastiff, Neapolitan Mastiff, Newfoundland, Portuguese Water Dog, Rottweiler, Saint Bernard, Samoyed, Siberian Husky, Standard Schnauzer, and Tibetan Mastiff. A detection dog or sniffer dog is a dog that is trained to and works at using its senses (almost always the sense of smell) to detect substances such as explosives, illegal drugs, or blood. Hunting dogs that search for game and search dogs that search for missing humans are generally not considered detection dogs. There is some overlap, as in the case of human remains detection dogs (sometimes called cadaver dogs), trained to detect human remains. They are also used for drug raids to find where the drugs are. In the state of California, dogs are trained to detect the Quagga Mussel on

boats at public boat ramps, as it is a invasive species. Sniffer dogs have also been enlisted to find bumblebee nests. The Bumblebee Conservation Trust has trained an English Springer Spaniel to detect the colonies, assisting them with the conservation of threatened species. Some prisons have dogs trained to detect illicit cell phones in prison cells.[1] A service dog is a type of assistance dog specifically trained to help people who have disabilities including visual or hearing impairment, and also to help people with mental disabilities including Post Traumatic Stress Disorder (PTSD) and severe depression. Some dogs are even trained to help with medical conditions such as recurrent seizures or diabetes. Additionally, they may also be trained to carry life support equipment such as oxygen tanks. Desirable character traits in service animals typically include good temperament or psychological make-up (including biddability and trainability) and good health (including physical structure and stamina). Service dogs are sometimes trained and bred by service dog organizations. Some dogs are donated by private breeders, and some are selected from shelters. Any breed or mixture of breeds of dog might produce a representative capable of service work, though few dogs have all of the health and temperament qualities needed. Labrador Retrievers, and mixes with that breed, are common now. Such a dog may be called a "service dog" or an "assistance dog," depending largely on country. Other common names include "helper dog," "aide dog," and "support dog." In the United States, the Code of Federal Regulations for the Americans with Disabilities Act of 1990 define a service animal as "any guide dog, signal dog, or other animal individually trained to do work or perform tasks for the benefit of an individual with a disability, including, but not limited to, guiding individuals with impaired vision, alerting individuals with impaired hearing to intruders or sounds, providing minimal protection or rescue work, pulling a wheelchair, or fetching dropped items."