Search

Background Cats are strict carnivores but possess a complex gastrointestinal (GI) microbial community that actively ferments dietary substrates that are not digested and reach the colon. The GI microbiota responses to dietary inclusion of resistant starches versus fibers have not been tested in cats. Thus, our objective was to evaluate the effects of diets enriched in resistant starch or fibers on the fecal characteristics, microbiome, and metabolite profiles of cats. Twelve healthy adult domestic shorthair cats (age = 9.6 ± 4.0 year; body weight = 3.9 ± 1.0 kg) were used in a replicated 3 × 3 Latin square design to test diets that were enriched with: (1) resistant starch (ERS), (2) a fiber-prebiotic-probiotic blend (FPPB), or (3) a fiber-prebiotic-probiotic blend + immune-modulating ingredients (iFPPB). In each 28-day period, 22 days of diet adaptation was followed by fecal and blood sample collection. Fecal samples were used for shotgun metagenomic sequencing. In addition, fecal and blood metabolite measurements and white blood cell stimulation was performed to assess immune function. Results A total of 1690 bacterial species were identified, with 259 species differing between fiber-rich and ERS treatments. In comparison with fiber-rich treatments that increased diversity and promoted Firmicutes and Bacteroidetes populations, resistant starch reduced microbial diversity and fecal pH, led to a bloom in Actinobacteria, and modified Kyoto Encyclopedia of Genes and Genomes orthology (KO) terms pertaining to starch and sucrose metabolism, fatty acid biosynthesis and metabolism, epithelial cell signaling, among others. Resistant starch also differentially modified fecal metabolite concentrations with relevance to GI and overall host health (increased butyrate; decreased propionate and protein catabolites - branched-chain fatty acids; phenols and indoles; ammonia) and reduced blood cholesterol, which correlated strongly with microbial taxa and KO terms, and allowed for a high predictive efficiency of diet groups by random forest analysis. Conclusion Even though domestic cats and other carnivores evolved by eating low-carbohydrate diets rich in protein and fat, our results demonstrate that the feline microbiome and metabolite profiles are highly responsive to dietary change and in directions that are predictable.

Periodontal disease is a common oral health condition occurring in adult dogs, yet it is a preventable disease. The objective of this study was to evaluate the efficacy of a novel dental chew in adult dogs. All animal care and experimental procedures were approved by the University of Illinois Institutional Animal Care and Use Committee prior to experimentation. Twelve female beagles (mean age = 3.50 yr; mean BW = 8.77 kg) were used in a crossover design consisting of two 28-d periods. All dogs consumed the same commercial kibble diet throughout the study. Control dogs were offered only diet, while the treatment group received the diet plus a daily dental chew (Authority Dental Chew Orashield system formula containing sodium hexametaphosphate and texture) 4 h after their meal. On d0 of each period, teeth were cleaned by a veterinary dentist. Teeth were then scored for plaque, calculus, and gingivitis by the same veterinary dentist that was blinded to treatments on d28 of each period. Breath samples were measured for breath halitosis (volatile sulfur compounds) using a halimeter on d1, 7, 14, 21, and 27 of each period. All tooth scoring data were analyzed using the Mixed Models procedures of SAS. Halimeter data were analyzed using repeated measures using Mixed Models procedures. Oral calculus coverage and thickness were less (P< 0.05) in dogs consuming the novel chew than control dogs, while plaque was not different among groups. Gingivitis scores and gingival bleeding were also less (P< 0.05) in dogs consuming the novel chew compared with control dogs. Breath volatile sulfur compound concentrations were reduced (P< 0.05) in dogs consuming the novel chew than control dogs. Our results suggest that the novel dental chew tested in the study may aid in reducing the risk of periodontal disease in dogs.

A variety of functional ingredients, including fibers, prebiotics, probiotics, and postbiotics may be added to pet foods to support gastrointestinal and immune health. While many of these ingredients have been tested individually, commercial foods often include blends that also require testing. This study was conducted to evaluate the effects of diets containing blends of fibers, "biotics," and/or spray-dried plasma on apparent total tract digestibility (ATTD), stool quality, fecal microbiota and metabolites, and immune health outcomes of adult dogs. A total of 12 healthy adult intact English pointer dogs (6 M, 6 F; age = 6.4 ± 2.0 yr; BW = 25.8 ± 2.6 kg) were used in a replicated 3 × 3 Latin square design to test diets formulated to: 1) contain a low concentration of fermentative substances (control diet, CT); 2) be enriched with a fiber-prebiotic-probiotic blend (FPPB); and 3) be enriched with a fiber-prebiotic-probiotic blend + immune-modulating ingredients (iFFPB). In each 28-d period, 22 d of diet adaptation was followed by a 5-d fecal collection phase and 1 d for blood sample collection. All data were analyzed using SAS 9.4, with significance being P0.05 and trends being P0.10. FPPB and iFPPB diets led to shifts in numerous outcome measures. Dry matter (DM), organic matter, fat, fiber, and energy ATTD were lower (P0.01), fecal scores were lower (P0.01; firmer stools), and fecal DM% was higher (P0.0001) in dogs fed FPPB or iFPPB than those fed CT. Serum triglycerides and cholesterol were lower (P0.01) in dogs fed FPPB or iFPPB than those fed CT. Fecal protein catabolites (isobutyrate, isovalerate, indole, and ammonia) and butyrate were lower (P0.05), while fecal immunoglobulin A (IgA) was higher (P0.01) in dogs fed FPPB and iFPPB than those fed CT. Fecal microbiota populations were affected by diet, with alpha-diversity being lower (P0.05) in dogs fed iFPPB and the relative abundance of 20 bacterial genera being altered in dogs fed FPPB or iFPPB compared with CT. The circulating helper T cell:cytotoxic T cell ratio was higher (P0.05) in dogs fed iFPPB than those fed CT. Circulating B cells were lower (P0.05) in dogs fed FPPB than those fed iFPPB, and lower (P0.05) in dogs fed iFPPB than those fed CT. Our results demonstrate that feeding a fiber-prebiotic-probiotic blend may provide many benefits to canine health, including improved stool quality, beneficial shifts to fecal microbiota and metabolite profiles, reduced blood lipids, and increased fecal IgA.A variety of functional ingredients—those that provide benefits beyond their nutritional value—may be added to pet foods to support gastrointestinal and immune health. While many of these ingredients have been tested individually, commercial foods often include blends that also require testing. This study was conducted to evaluate the effects of diets containing blends of dietary fibers and other functional ingredients on nutrient digestibility and the stool characteristics and immune health outcomes of adult dogs consuming them. Treatments included a control diet containing low amounts of dietary fiber, a diet containing a fiber–prebiotic–probiotic blend, and a diet containing the fiber–prebiotic–probiotic blend as well as immune-modulating ingredients. The test diets were shown to shift many outcome measures. First, they were shown to reduce nutrient digestibility and decrease fecal scores (more firm stool). Second, test diets reduced blood lipids and beneficially altered fecal metabolite concentrations. Third, test diets increased fecal immunoglobulin A concentrations, suggesting enhanced gut immunity. Lastly, the test diets shifted fecal bacterial populations. Our results demonstrate that feeding a fiber–prebiotic–probiotic blend may provide many benefits to canine health, including improved stool quality, beneficial shifts to fecal bacteria and metabolite profiles, reduced blood lipids, and enhanced gut immunity.