A ratter is any dog used for catching and killing rats and similar vermin.[1] Specialized rat-catching breeds are found in many countries. A typical ratter is small to medium-sized and has a short and smooth coat, however a wide range of dog breeds and landraces may be used.[2][1][3] The use of ratting dogs is widely considered to be the most environmentally friendly, humane and efficient methods of exterminating rodents.[4][2] Ratting dogs are considered more efficient than domestic cats.[1]
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