In "Dog Trouble", Tom and Jerry confront a huge dog appropriately named Bull Dog, as intolerant as he is aggressive. This very early incarnation of Spike, the recurring bulldog characters, embodied brute force, while Spike evolved into a sympathetic character, regularly siding with Jerry against Tom.
He also later had a son, Tyke, a bull pup, whom he was very protective of him. Oftentimes, Tom would accidentally hurt or bother Tyke (usually deliberately planned by Jerry), and Spike would rough him up for that ....