The Australian Cattle Dog (ACD), or simply Cattle Dog, is a breed of herding dog originally developed in Australia for droving cattle over long distances across rough terrain. The Australian Cattle Dog breed standard states that it should have well-conditioned muscles, even when bred for companion or show purposes, and that its appearance should be symmetrical and balanced, with no individual part of the dog exaggerated. The Australian Cattle Dog breed standard states that it should have well-conditioned muscles, even when bred for companion or show purposes, and that its appearance should be symmetrical and balanced, with no individual part of the dog exaggerated. It should not look either delicate or cumbersome, as either characteristic limits the agility and endurance that is necessary for a working dog. Both red dogs and blue dogs are born white (except for any solid-coloured body or face markings) and the red or black hairs show from around 4-weeks of age as they grow and mature. As with all dogs, regular attention to nails, ears and teeth will help avoid health problems.