 The Campeiro Bulldog helped its owners in handling cattle, but not as a herding dog.The dogs that excelled in working with wild cattle and swines were highly valued as much as those dogs that knew how to guard the cart and the horse of the tropeiros (the drivers of mules and horses' commissions that traveled between regions of Brazil during the 17th century).The breed has been exhibiting the functional features of its probable ancestor, namely the Old English Bulldog, which could hold swine through their ears to the slaughterhouse and could dominate a wild cow of up to 400 kg on its own.