J Am Vet Med Assoc. 2001 Mar; 218(6): 892-6.

Administration of charcoal, Yucca schidigera, and zinc acetate to reduce malodorous flatulence in dogs.

Giffard CJ, Collins SB, Stoodley NC, Butterwick RF, Batt RM.

Waltham Centre for Pet Nutrition, Waltham-on-the-Wolds, Melton Mowbray, Leicestershire, UK.

OBJECTIVE: To determine whether feeding activated charcoal, Yucca schidigera, and zinc acetate would ameliorate the frequency and odor characteristics of flatulence in dogs. DESIGN: In vitro screening of active agents followed by a randomized controlled trial. ANIMALS: 8 adult dogs. PROCEDURE: A fecal fermentation system was used to assess the effects of activated charcoal, Yucca schidigera, and zinc acetate alone and in combination on total gas production and production of hydrogen sulfide, the primary determinant of flatus malodor in dogs. All 3 agents were subsequently incorporated into edible treats that were fed 30 minutes after the dogs ate their daily rations, and the number, frequency, and odor characteristics of flatulence were measured for 5 hours, using a device that sampled rectal gases and monitored hydrogen sulfide concentrations. RESULT: Total gas production and number and frequency of flatulence episodes were unaffected by any of the agents. Production of hydrogen sulfide in vitro was significantly reduced by charcoal, Yucca schidigera, and zinc acetate by 71, 38, and 58%, respectively, and was reduced by 86% by the combination of the 3 agents. Consumption of the 3 agents was associated with a significant decrease (86%) in the percentage of flatulence episodes with bad or unbearable odor and a proportional increase in the percentage of episodes of no or only slightly noticeable odor. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that activated charcoal, Yucca schidigera, and zinc acetate reduce malodor of flatus in dogs by altering the production or availability of hydrogen sulfide in the large intestine.