Why Does My Dog (or Cat) Pass Gass So Much? (and Why Does It Smell So Bad?)

It happens sometimes to dog (and cat) owners… that “certain odor” emanating from the back end of your favorite friend. It doesn’t matter if you have a Chihuahua or a Great Dane, sometimes that stench can be enough to clear the room!

Does your dog or cat pass excessive gas? Flatulence in animals is as normal as it is in humans (Come on, we all do it). And just like in humans, when it becomes excessive or especially rank, dog and cat flatulence may be an indication of something serious.

Dog and Cat Digestion Is Different

The GI tract of dogs and cats are similar to humans in that we all have the same basic parts. How we use those parts is vastly different in many ways, however.¹

First, let’s take a look at your dog. For humans, the breaking down of the food in the mouth by chewing is “the first step of digestion.” For dogs, this not the case.² A dog’s teeth have been designed to bite off large pieces and eat quickly. Their mouths are hinged and meant for good-sized chunks of meat, bone, and fat. Because of this, a dog’s stomach plays a large role in the entire digestive process.

Dogs tend to have higher levels of hydrochloric acid in the stomach than humans do, which helps break down bits of bone and fat.³ Dogs can also regurgitate and re-swallow food that has not been processed in the right way. In general, dogs have one of the shortest digestive systems of all mammals.

A cat’s system is actually even a little shorter than a dog’s. The other main distinction lies in tooth structure. Dogs have molars which are capable of crushing plant material. A cat’s teeth, on the other hand, are designed specifically for meat. This means that while dogs can eat some vegetables, cats are specifically designed for the hunt.⁴

Diets, Parasites and More: 12 Reasons Why Your Dog or Cat Passes a Lot of Gas

Some gas after eating is normal for a dog or cat. If your pet has a lot of flatulence, however, it may be time to consider one or more of the following:

#1 – The wrong kind of diet. This includes diets heavy in soy, beans, or peas. According to some experts, diets high in “fermentable fibers” such as psyllium or oat bran can also cause more gas.⁵ Some animals also have an intolerance to corn and wheat.

#2 – Consuming dairy. Like an increasing number of humans, many dogs and cats are lactose intolerant.

#3 – Eating human table scraps. You may think you are giving your dog or cat love by feeding them from the table, but if you share types of food they cannot digest, you may be doing more harm than good. Both dogs and cats have a hard time digesting food additives, preservatives, and spicy foods. Other foods, like chocolate, may be deadly in large amounts.

#4 – Eating spoiled food. Your pet’s GI tract is heartier than yours, but it still has its limits! Spoiled and rotten food might smell good to your pet, but it can also make them sick.

#5 – Overeating. This could be because you are feeding your pet too much or because they are bored or nervous and are eating compulsively.

#6 – Eating too fast. Dogs and cats tend to eat quickly, but eating too fast can cause Aerophagia, which is an increased swallowing of air.

#7 – Poor food absorption. Some pets have slower-than-normal digestion or absorption problems. If this is the case, food particles may tend to putrefy in the gut and cause especially pungent flatulence. If you suspect this is the case, contact your vet.

#8 – Parasites. Parasites can not only disturb the bacterial balance in the gut, they can also feed off nutrients meant for your pet and cause serious (and sometimes life-threatening) conditions.⁶

#9 – Hairballs (in cats). Hairballs are created as a result of your cat licking and swallowing their own hair when self-grooming. Most of the time your cat’s digestive system is strong enough to pass these balls. Sometimes, however, hairballs can get clogged, resulting in intestinal disturbances including gas and vomiting.⁷

#10 – Being fed right after exercise (for dogs). Always wait at least an hour before and after a meal before taking your dog on a run or encouraging other forms of intense exercise. Doing so may result in canine bloat,⁸ a serious condition that requires immediate veterinary attention.

#11 – Brachycephalic (i.e. flat-faced breeds for both dogs and cats). Pugs, bulldogs, and Persian cats are examples of Brachycephalic breeds that have a hard time digesting food, amongst their many other health problems.⁹ Unfortunately, demand for the “flat-faced” look is high, which benefits breeders but not pets nor their pet parents. In fact, Kennel Clubs in the UK have even campaigned to greeting card companies to stop featuring French Bulldogs and Persian kitties in their card lines as a way of discouraging the popularity of these breeds.¹⁰

#12 – Specific disease conditions. These could include cancers¹¹ or benign tumors, Small Intestinal Bacterial Overgrowth (SIBO), Inflammatory Bowel Disease (IBD), enteritis, Exocrine Pancreatic Insufficiency (EPI), and some respiratory diseases.

When to See a Vet About Flatulence

If you find that dog or cat flatulence is getting out of hand or that it’s happening in conjunction with other symptoms, it may be time to see your holistic veterinarian for advice. Except in the case of emergencies, the first course of action for you (besides opening a window) should always be observation. Take note of how, when, what, and how much your pet eats, drinks, and relieves itself on a regular basis. Check their overall behavior as well. Odds are, with a little adjustment on both your parts, you will be able to enjoy your best friend again… minus the obnoxious odor!

1. http://www.cpp.edu/~honorscollege/documents/convocation/AG/AVS_Jolitz.pdf
2. https://www.vetinfo.com/dog-digestive-system.html
3. https://www.ncbi.nlm.nih.gov/pubmed/3701609
4. https://www.waltham.com/document/nutrition/cat/dog/differences-between-cat-and-dog/284/
5. https://www.ncbi.nlm.nih.gov/pubmed/10758366
6. http://www.petsandparasites.org/resources/pets-parasites-and-people
7. https://www.petmd.com/cat/grooming/evr_ct_cat_hairballs
8. https://www.dogbreedinfo.com/articles/caninebloat.htm
9. https://www.acvs.org/small-animal/brachycephalic-syndrome
10. https://www.theguardian.com/lifeandstyle/shortcuts/2018/feb/12/passion-flat-faced-dogs-cats-vets-valentines-day-cards
11. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3617004/