Effects of dietary macronutrient profile on apparent total tract macronutrient digestibility and fecal microbiota, fermentative metabolites, and bile acids of female dogs after spay surgery

Abstract

Obesity and estrogen reduction are known to impact the gut microbiota and gut microbial-derived metabolites in some species, but limited information is available in dogs. The aim of this study was to determine the effects of dietary macronutrient profile on apparent total tract macronutrient digestibility, fecal microbiota, and fecal metabolites of adult female dogs after spay surgery. Twenty-eight adult intact female beagles (age: 3.02 ± 0.71 yr, BW: 10.28 ± 0.77 kg; BCS: 4.98 ± 0.57) were used. After a 5-wk baseline phase (wk 0), 24 dogs were spayed and randomly allotted to one of three experimental diets (n=8/group): 1) control (CO) containing moderate protein and fiber (COSP), 2) high-protein, high-fiber (HPHF), or 3) high-protein, high-fiber plus omega-3 and medium-chain fatty acids (HPHFO). Four dogs were sham-operated and fed CO (COSH). All dogs were fed to maintain BW for 12 wk after spay, then allowed to consume twice that amount for 12 wk. Fecal samples were collected at wk 0, 12, and 24 for digestibility, microbiota, and metabolite analysis. All data were analyzed using repeated measures and linear Mixed Models procedure of SAS 9.4, with results reported as change from baseline. Apparent organic matter and energy digestibilities had greater decreases in HPHF and HPHFO than COSH and COSP. Increases in fecal acetate, total short-chain fatty acids, and secondary bile acids were greater and decreases in primary bile acids were greater in HPHF and HPHFO. Principal coordinates analysis of weighted UniFrac distances revealed that HPHF and HPHFO clustered together and separately from COSH and COSP at wk 12 and 24, with relative abundances of Faecalibacterium, Romboutsia, and Fusobacterium increasing to a greater extent and Catenibacterium, Bifidobacterium, Prevotella 9, Eubacterium, and Megamonas decreasing to a greater extent in HPHF or HPHFO. Our results suggest that high-protein, high-fiber diets alter nutrient and energy digestibilities, fecal metabolite concentrations, and fecal gut microbiota, but spay surgery had minor effects. Future research is needed to investigate how food intake, nutrient profile, and changes in hormone production influence gut microbiota and metabolites of dogs individually and how this knowledge may be used to manage spayed pets.

Different Diet Energy Levels Alter Body Condition, Glucolipid Metabolism, Fecal Microbiota and Metabolites in Adult Beagle Dogs

“…By analyzing the pH of the fresh feces of dogs, it was shown that the long-term consumption of either low-or high-energy diets caused fecal acidification, which was related to the metabolites in the feces and the composition of the gut microbiota, in several studies on canine nutrition [50][51][52][76][77][78]. Based on the above, the total SCFAs in the feces were measured in this study and were increased significantly in the Le group, especially for acetic acid and butyric acid.…”

Collaborative Metabolism: Gut Microbes Play a Key Role in Canine and Feline Bile Acid Metabolism

“…Over the past 5 years, microbial-derived BAs have been increasingly studied in canines ( Table 1 ). Studies in healthy dogs have characterized the microbial-derived BAs during the development of puppies [ 114 ], as well as the impact of antimicrobials [ 59 , 115 , 116 , 117 , 118 ] and diet [ 119 , 120 , 121 , 122 , 123 , 124 , 125 , 126 ] on the BA pools of healthy dogs. Additional studies on disease states have largely focused on the context of gastrointestinal [ 52 , 64 , 127 , 128 , 129 , 130 , 131 ] and pancreatic disease [ 128 , 132 ], with additional information characterizing microbial-derived BAs in canine obesity [ 119 , 125 ], diabetes mellitus [ 113 ], and myxomatous mitral valve disease (MMVD) [ 133 ].…”

“…Therefore, in healthy dogs, additional multi-omics studies are required to characterize collaborative BA metabolism, specifically describing canine gut microbes mechanistically responsible for BA biotransformations in health. In the following sections, the impact of antimicrobials [ 59 , 115 , 116 , 117 , 118 ] and diet [ 119 , 120 , 121 , 122 , 123 , 124 , 125 , 126 ] on the BA pools of healthy dogs will be reviewed.…”

“…As expected, diet impacts the gut microbiota and microbial-derived SBAs, but the response is dependent on the diet fed. Diet types studied to date in dogs include the following: high protein, high fat, low fiber (HP-HF-LF) [ 126 ]; high protein, high fat, low fiber consistent with bones and raw food (BARF) [ 121 ]; high protein, high fiber (HP-HF) [ 122 ]; and grain-free diets [ 120 , 123 , 124 ].…”

“…When dogs were fed a high-protein and high-fiber diet, no alterations in fecal microbial-derived BAs were reported [ 122 ]. Healthy female research dogs ( n = 28) were fed a control diet for a period of five weeks with 22.3% crude protein and 12.1% total dietary fiber on a dry matter basis [ 122 ]. Four dogs had a sham spay surgery performed on them and were continued on the control diet for 24 weeks [ 122 ].…”