You can give her a half dose of beano, probiotics, there are also dog medications for gas but they can be expensive. Also a diet that is high in protien or corn based can cause flatulence. Plenty of exersice can help with it too. My three year old pit is the same way, constantly passing gas and clearing out the room. We just adopted her a week ago and wasnt sure if it was stress from the move but if it doesnt improve we will be trying some beano.