This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
If you’re here after reading Part 1: What Are Dog Farts Made Of? and you came back for the dog fart suit, stay with me; it’ll return momentarily.
Everyone knows that dogs fart. In 1998, the New Zealand Veterinary Journal published the report, Flatulence in Pet Dogs, finding that “most owners accept flatulence and were unconcerned about its consequence” (Yes, you heard that right. Veterinarians distributed a questionnaire on dog farts, and over 100 owners completed it. Kiwis: my type of people). The understanding here is simple: I fart, you fart, the dog farts.
Of all the things that irk dog owners — barking, toileting in the house, enjoying the trash — flatulence is not high on the list. To my knowledge, farting, unlike the other behaviors mentioned, is not associated with dog relinquishment to animal shelters.
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But anecdotally, dog owners note that they would not be heartbroken if their dog’s farts were a little less smelly, raising the question “Is it possible to decrease the stink in dog farts?”
The dog fart suit researchers you met in Part 1: What Are Dog Farts Made Of? are on the case! And you’d be on the case too if you had a special dog fart suit that allowed you to measure the stinkiness (hydrogen sulfide concentration) of dog farts in real time. Like any good researcher, you might investigate which compounds affect dog farts, rendering them benign or incredibly noxious.
So which ingredients might decrease the stink in dog farts? There were a few prime candidates. In one study of human farts (where subjects were asked to consume pinto beans beforehand “to ensure flatus output” – you can’t make this stuff up), charcoal and zinc acetate reduced fart stinkiness. A different study showed that Yucca schidigera (say that three times fast) reduced stink-inducing hydrogen sulfide concentrations in dog poop. While those substances are available as dietary supplements, don’t use any of them without veterinary approval.
Return of the dog fart suit
To investigate whether a combination of charcoal, Yucca schidigera and zinc acetate would decrease the stink in dog farts, dogs at the Waltham Center for Pet Nutrition got back into their fart suits. (The researchers call it a “flatulence-collecting system for dogs.” We’ll have to agree to disagree.) Then the dogs consumed treats containing the three ingredients.** The fart suit captured and measured hydrogen sulfide concentrations, and farts were assigned an odor rating based on the observations of the Odor Judge mentioned in Part 1. Farts were rated as:
no odor
slightly noticeable
mildly unpleasant
bad
unbearable
How did the farts turn out? The treats containing the three ingredients did the trick!! They did not decrease the number of farting episodes – a farting dog will still continue to toot even after eating the treats – but the stench of those emissions was less aversive. Farting “episodes rated as 4 (bad) or 5 (unbearable) were significantly decreased, and [the] percentage of episodes rated as 2 (slightly noticeable) was significantly increased.”
Key fart facts
Hydrogen sulfide is behind the stink in stinky dog farts.
Dogs fed treats containing charcoal, Yucca schidigera and zinc acetate continued to fart but produced fewer stinky farts.
But there’s more! Veterinarians remind that a number of factors are behind a farting dog, including a sedentary lifestyle, eating quickly and swallowing air, as well as chowing down on difficult-to-digest food. Is this your dog? See resources by the ASPCA and Pet MD for more info.
Thanks for spending time exploring the Science of Dog Farts (Part 1 and Part 2)! The perfect conversation starter at your next party. What your dog's farting story?
** In this study, each biscuit treat contained “320 mg of activated charcoal, 2.5 mg of Yucca schidigera, and 17 mg of zinc in the form of zinc acetate dihydride.” Dogs were fed 1 treat per 11 lb of body weight. Jessica Hekman, DVM, MS and genomics PhD student adds, "We don't know if this stuff is safe to feed regularly. But that's one of the things good research does -- provide ideas for future research. Like testing the safety of activated charcoal in anti-fart-stink dog treats."
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Acknowledgements: Thanks to Jessica Hekman of Dog Zombie for her review and comments.
Images: Featured Image, Warning Explosive Dog Farts, by CGP Gey; Girl & Dog, Nearby-Previously Unnoticed, by Gordon. Both via Flickr Creative Commons. Device to measure dog gas, Figure 1 in Collins et al. 2001 (below).
References
Collins et al. 2001. Development of a technique for the in vivo assessment of flatulence in dogs. American Journal of Veterinary Research. 62, 1014-1019.
Giffard et al. Administration of charcoal, charcoal, Yucca schidigera and zinc acetate to reduce malodorous flatulence in dogs. JAVMA 218, 892-896.
Jones et al. 1998. Flatulence in pet dogs. N Z Vet J. 46, 191-193.
Suarez et al. 1998. Identification of gases responsible for the odour of human flatus and evaluation of a device purported to reduce this odour. Gut 43, 100-104.