The American Bulldog is a powerful, athletic, medium-large sized dog with great muscular strength and endless endurance. There is a wide size and weight latitude in the breed, which vary according to the type (Johnson, Scott, Painter/Margentina, Old Southern Whites type or hybrid) but overall the american bulldog is always "well balanced". Exaggeration of any part of the dog would reduce his effectiveness at work.
The principal architects of today's American Bulldog are Allen Scott and John D. Johnson. Before they renamed the breed to 'American Bulldog' the dogs were known by a variety of different regional names: Southern White, Hill Bulldog, Country Bulldog, White Bulldog, White English Bulldog, English White, and commonly just "Bulldog".
As well as having varying names according to region, they also had local bloodline variations in appearance and size and also differences according to the tasks intended of them by their breeders and this is part of the reason why the American Bulldog breed conformation standards laid down by the registries allow for such a wide variation in type.
Initially Scott and Johnson had similar dogs and they freely bred and traded dogs with each other. Johnson's Dick the Bruiser and Scott's Mac the Masher were their foundation dogs. These two dogs were Old Southern Whites. Alan Scott and John D Johnson scoured the mountains and valleys of those Southern states looking for bulldogs and buying up those that they liked and they began a breeding program together.
Later on they had a falling out and JDJ began to develop and refine his trademark heavier-built style of American Bulldog. From the breeding programs of these two men, two distinct strains have emerged, commonly called the Johnson type or the Bully/Classic class and the Scott type or Standard/Performance class.
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