Bulldog is the name for a breed of dog commonly referred to as the English Bulldog. Other Bulldog breeds include the American Bulldog, Olde English Bulldogge, and the French Bulldog. The Bulldog is a muscular, heavy dog with a wrinkled face and a distinctive pushed-in nose. The American Kennel Club (AKC), The Kennel Club (UK), and the United Kennel Club (UKC) oversee breeding standards. In Rio and Rio 2, Luiz is a Bulldog.
Although bulldogs appear like thier mean or rough or people describe as they are, bulldogs are actually friendly dogs. Luiz first appeared very dangerous, but he was just joking when he was meeting Blu an Jewel.