Why your dog farts & what you can do about it

Against my better judgement, I sometimes give my dog treats that don’t quite fit into the diet of healthy canine nutrition. Rest assured, when the aftermath of ‘dog farts’ strikes, I will pay the price when it smells like something died in my house.

Farting dogs can be funny and for some gas isn’t a big deal. For others the smell can be so foul you need a peg on your nose while around your dog. While gas is normal from time to time, it is not normal for dog farts to occur all the time. Sadly, many owners have accepted their chronic gassy canines as just the way they are. We tend not to question the things we have already accepted as normal, but what if we did?

Luckily, most cases of gas aren’t very serious.You can treat them effectively with diet changes, feeding adjustments, and proper exercise. However, If your dog’s gas comes with symptoms like vomiting, chronic diarrhoea, pain, or restlessness, you need to contact your vet immediately.

It goes by many names

People use many different terms to describe the release of gas from the body. The medical term is ‘flatus’ and is defined as ‘gas expelled through the anus’. I haven’t been able to find any studies of rectal gas excretion rates in dogs but in people they range from 400 to 1500 ml/day. People eating their usual foods pass gas per rectum an average of eight to ten times per day with an upper normal limit of 20 times per day.

Where does the gas come from?

The most common cause of excessive gas in dogs is diet. While trying new food can occasionally lead to a fart, chronic gas often results from poorly digested food, causing excessive fermentation in the small intestine.

Foods high in non-absorbable oligosaccharides often lead to increased intestinal gas in dogs. This is because dogs lack the enzymes to break down these sugars, causing bacteria in the large intestine to ferment them. This fermentation produces gases like carbon dioxide and hydrogen. Consequently, dogs often experience flatulence and GI upset from consuming soybeans, peas, beans, milk products, high-fat diets, and spicy foods.

When your dog eats or drinks, he swallows small amounts of air that then accumulate in the digestive system. Your dog gets rid of this accumulated air by farting or burping. Flat-faced breeds like Pugs, Boxers, Bull Mastiffs, and Boston Terriers often swallow more air. Working and sporting dogs, as well as “fast eaters,” also face a higher risk of air ingestion. In humans, gases can move through the GI tract at 10cm a second, and ingested air can lead to flatus within 15 to 35 minutes

The smelly dog fart

Dog farts consist of 99% odorless gases, while the remaining 1% contains sulfur-producing, odorous gases. A diet rich in sulfur leads bacteria in the gut to produce more sulfides, making farts smellier. Consuming nuts, spices, cruciferous vegetables (like broccoli, cabbage, cauliflower, and Brussels sprouts), and high-protein ingredients often amplifies the production of these smelly gases.

Silent but deadly

When humans fart, vibrations of the anal opening produce the sounds. These sounds depend on the speed of ejection of the gas and the tightness of the sphincter muscle of the anus.

Most dog farts are silent or rarely more than a little “poof”. One explanation could be down to anatomy. Your dog’s digestive system is horizontal which puts less pressure on the anal opening, thus the gas is expelled more slowly. Another theory suggests it’s because dogs don’t feel embarrassed about farting, so the sphincter is more relaxed, leading to less noisy farts.

How can you reduce your dog’s flatus?

To reduce your dog’s flatulence, feed them a consistent and healthy diet. As mentioned, specific proteins, carbohydrates, and fibers can influence gas production. For instance, in a human study, a diet comprising half pork and half baked beans increased flatus from 15ml to a significant 176ml/hour.

Feeding your dog highly digestible foods is essential as they leave fewer residues for bacterial fermentation in the large intestine. For example, foods with rice as the primary carbohydrate lead to less gas than those with wheat or corn. And since proteins rich in sulfur can affect the odor of the gas, consider changing your dog’s protein source. It’s also best to avoid leguminous proteins like soybean meal. Additionally, certain fiber-rich foods, including bran, soy fiber, soy hulls, pea fiber, and beet pulp, may intensify flatulence.

Bottom line (pun indented)

  • To prevent excessive air swallowing, feed several small meals a day and discourage rapid eating by using a slow feeder. A cupcake pan can be useful as food can be split into the separate holes.
  • Changing the main protein or carbohydrate source in the food may benefit some dogs.
  • Feed a highly digestible food. Avoid low-quality proteins (usually of plant origin) and foods containing ingredients from legumes such as soy beans peas, peanuts and lentils.
  • Vegetarian based foods can be problematic because they often include potentially odoriferous sulphur-containing vegetables and legumes.
  • Avoid foods or treats containing lactose, especially in dogs with lactase deficiency or with underlying GI disease.
  • Know your dog’s allergies and food sensitivities, and steer clear of foods that could upset their stomach.
  • Avoid cruciferous vegetables (broccoli, cauliflower, Brussels sprouts and cabbage).

We’ve reached the end of the blog, and I hope the information has helped you better understand the changes you can make to reduce your dog’s gas. Every dog is unique, just as their dietary needs are. If you’re uncertain about the best diet for your dog or are interested in a home-prepared diet tailored specifically for them, I’d be happy to help. Your dog’s health and comfort are paramount, and a personalised diet can be transformative, especially for dogs with chronic digestive issues.

Please don’t hesitate to reach out. You can contact me at kristina@elmoskitchen.com. Your feedback and suggestions are always welcome.