Select Dietary Fiber Sources Improve Stool Parameters, Decrease Fecal Putrefactive Metabolites, and Deliver Antioxidant and Anti‐inflammatory Plant Polyphenols to the Lower Gastrointestinal Tract of Adult Dogs
Authors: Fritsch Dale A. , Wernimont Susan M. , Jackson Matthew I. , Gross Kathy L. 
Published: June 2021

Dogs possess a gut microbiome capable of fermenting a variety of plant fibers. Select dietary fiber sources may offer opportunities to optimize canine health by providing both fermentable carbohydrates & plant‐derived compounds. 39 adult dogs were fed a low fiber, Control food (CF) for 4 weeks, then randomized to one of two moderate fiber Test foods & fed for 4 weeks in a crossover design. All foods were complete & balanced dry foods & met 2017 AAFCO guidelines for adult dogs. All dogs were fed to maintain body weight. The CF contained 3,411 kcals/kg, 2.2 g total dietary fiber, TDF, 0.5 g soluble fiber, SF, 1.7 g insoluble fiber, INSF per 100 kcal; Test food A (TFA) contained 3,273 kcal/kg, 5.0 g TDF, 0.8 g SF, 4.2 g INSF per 100 kcal; Test food B (TFB) contained 3,557 kcal/kg, 6.3 g TDF, 1.0 g SF, 5.3 g INSF per 100 kcal. Fiber sources in the CF included cracked pearled barley, whole corn, whole grain oats, cellulose; TFA included cracked pearled barley, whole corn, whole grain oats, ground pecan shells, cellulose, flaxseed, dried beet pulp, dried citrus pulp, pressed cranberries, dried pumpkin, psyllium seed husks, & ginger root; TFB included cellulose, rice hulls, corn, wheat, beet pulp, psyllium seed husks, & fructooligosaccharides. Stool samples were collected after 4 weeks of feeding CF & after 4 weeks of feeding each Test food & were scored on a 5 point scale (1= liquid stool to 5= firm stool), homogenized, & frozen at −80C within 1 hour of defecation. Untargeted metabolomics analysis was performed by a commercial lab. Fecal short chain fatty acids (SCFAs) were analyzed using liquid‐liquid extraction & gas chromatography with flame ionization detection. All study protocols were reviewed & approved by the Institutional Animal Care & Use Committee, Hill's Pet Nutrition, Inc. Linear mixed models were used to analyze fecal pH, ammonium, and metabolites. Results significant at p<0.05 are reported. TFA significantly decreased total putrefactive fecal branched SCFAs (isobutyric, 2‐methylbutyric, & isovaleric acids), increased fecal acetic acid, & decreased fecal ammonium vs. CF & TFB. Both Test foods improved stool scores vs. CF. In addition, TFA increased fecal saccharolytic products ribulose/xylulose & arabinose derived from fiber vs. CF & TFB. Furthermore, TFA increased fecal antioxidant & anti‐inflammatory plant compounds such as hesperetin, ponciretin, limonin, sinensetin, naringenin, diosmetin, eriodictyol, & narirutin vs. CF & TFB. TFA containing specialized plant fiber ingredients improved stool parameters, increased fecal saccharolytic & fermentative metabolites, decreased putrefactive end products, & delivered antioxidant & anti‐inflammatory plant‐derived polyphenol postbiotics to the lower GI tract of healthy adult dogs. These findings may have implications for the management of canine inflammatory gastrointestinal diseases.Support or Funding InformationThis study was funded by Hill's Pet Nutrition, Inc.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.