Dogs do have gas, it is normal. They fart just like we do, however if a dog seems to have a lot of flatulence, this is not normal, and could be a sign of internal problems, or poor diet.
Does My Dog's Diet Make My Dog Fart?
Just as some foods make humans gassy, some foods make dogs fart. Beans are one of the foods often associated with causing gas in pets and humans. Beans are sometimes given to dogs as treats, or they sometimes steal them from the garden. Cabbage, Brussels sprouts, and broccoli, can all cause dogs to be windy. In fact too much of any thing they do not normally eat can cause minor stomach irritation, leading to gas.
Additionally some ingredients in pet foods can cause gas. Of these the filler ingredients are often linked to flatulence in dogs; corn, wheat, and soy. Some dogs have difficulty digesting pork, or beef, so these are also related to making a dog gassy. Dairy products can also cause a dog to have bad gas.
Canned food in general tends to make dogs more gassy than a diet of dry kibble.
Sudden diet changes of any kind can cause the dog to have gas. Even switching from one bag of dog food to another when the food uses “meatmeal” can cause problems because meat meal could be any dead animal and as such different batches of food could contain different meat sources.
Lower quality foods use fat to add flavor, the fat can be hard on the dog's digestive system and cause gas. Lower quality dog food can be spotted easy, it often contains cheap filler ingredients such as by-products or corn.
Has the dog been drinking dirty water, eating dead animals, or being feed a lot of snacks?
Intestinal worms and parasites can make a dog have gas. To find out what kind of worms your dog has, or if your dog has worms at all, you can take a stool sample to the veterinarian. They will also help you find the right kind of wormer, as not all wormers kill all types of worms.
Sometimes there is a more serious medical concern; something wrong with the dog. If you cannot find the source of your dog's flatulence problem, and the problem seems excessive, or sudden, a trip to the veterinarian might help provide some answers.
An obese dog is more likely to have digestive disorders and gas than a dog in good physical condition. Also note that older dogs tend to have more gas because their digestive system is not as fit as it once was, but you should still want to make sure there is not something else going on with your pooch.