Gassy Dog

My American Pitbull Terrier has the worst gas. She is only around 6 years old and has the walking farts. She toots when she walks up the steps, jumps off the couch or makes any sudden moves. She doesn't toot every sudden move but most of them. I rescued her from an abandoned house so we don't know her full health history but we do know she's had at least 1 litter of puppies. Her health is great and she eats Rachel Ray just 6 food. We've tried many brands of food and nothing helps. From my experience pitbulls are gassy dogs in general.