both of my boxers have gas i think that it is just a boxer thing mine do it and then look around as if to say who did that!!!
We found that by giving them a better dog food they tended to fart less & have fewer stools.
You can do something about this for your dog, try some different dry food, I was lucky, by the time I tried the third diffent food I found that my Boxer almost never has gas problems.
Ha Ha! Mine does, too! Sometimes the type of food or treats makes it worse or better.