Effects of dietary fiber and biotic supplementation on apparent total tract macronutrient digestibility and the fecal characteristics, metabolites, and microbiota of healthy adult dogs.

Dietary fibers and biotics have been shown to support gastrointestinal health in dogs, but are usually tested individually. There is value in testing fiber-biotic combinations that are commonly used commercially. Therefore, this study was conducted to determine the apparent total tract macronutrient digestibility (ATTD) of diets supplemented with fibers or biotics and to evaluate their effects on the fecal characteristics, metabolites, microbiota, and immunoglobulin A (IgA) concentrations of dogs. Twelve healthy adult female beagle dogs (age = 6.2 ±â€…1.6 yr; body weight = 9.5 ±â€…1.1 kg) were used in a replicated 3 × 3 Latin square design to test three treatments: 1) control diet based on rice, chicken meal, tapioca starch, and cellulose + a placebo treat (CT); 2) diet based on rice, chicken meal, garbanzo beans, and cellulose + a placebo treat (GB); 3) diet based on rice, chicken meal, garbanzo beans, and a functional fiber/prebiotic blend + a probiotic-containing treat (GBPP). In each 28-d period, a 22-d diet adaptation was followed by a 5-d fecal collection phase. Fasted blood samples were collected on day 28. Data were analyzed using the Mixed Models procedure of SAS 9.4, with P < 0.05 being significant and P < 0.10 being trends. ATTD of dry matter (DM), organic matter, and energy were lower (P < 0.001) and DM fecal output was higher (P < 0.01) in dogs fed GBPP than CT or GB, whereas ATTD of crude protein was higher (P < 0.001) in dogs fed CT and GBPP than GB. ATTD of fat was higher (P < 0.001) and wet fecal output was lower (P < 0.01) in dogs fed CT than GB or GBPP. Fecal DM% was higher (P < 0.001) in dogs fed CT than GBPP or GB, and higher in dogs fed GBPP than GB. Fecal short-chain fatty acid concentrations were higher (P < 0.001) in dogs fed GB than CT or GBPP, and higher in dogs fed GB than GBPP. Fecal IgA concentrations were higher (P < 0.01) in dogs fed GB than CT. Fecal microbiota populations were affected by diet, with alpha diversity being higher (P < 0.01) in dogs fed GB than CT, and beta diversity shifting following dietary fiber and biotic supplementation. The relative abundance of 24 bacterial genera was altered in dogs fed GB or GBPP than CT. Serum triglyceride concentrations were lower in dogs fed GB than GBPP or CT. Our results demonstrate that legume-based dietary fibers, with or without prebiotics and probiotics, reduce ATTD, increase stool output, beneficially shift fecal metabolites and microbiota, and reduce blood lipids in adult dogs.

Functional fibers and biotics have demonstrated the potential to modulate the gut microbiome and improve gastrointestinal health in dogs, but are often tested individually. Research investigating unique fiber/biotic combinations is needed. Twelve dogs were used in a replicated 3 × 3 Latin square design to test the efficacy of three dietary treatments on apparent total tract macronutrient digestibility (ATTD) and the fecal characteristics, metabolites, microbiota, and immunoglobulin A concentrations of dogs. Treatments included a low-fiber control diet without prebiotics or probiotics + a placebo treat, a diet containing garbanzo beans + a placebo treat (GB), and a diet containing garbanzo beans and a prebiotic blend + a probiotic (Bacillus subtilis and Bacillus amyloliquefaciens) treat (GBPP). ATTD was reduced and stool output was greater in dogs fed GB or GBPP than controls. Fecal short-chain fatty acids were higher in dogs fed GB or GBPP than controls. Fecal immunoglobulin A was higher, while blood lipids were lower in dogs fed GB than control. Finally, GB and GBPP shifted fecal bacterial populations. Our results demonstrate that legume-based dietary fibers, with or without prebiotics and probiotics, reduce ATTD, increase stool output, beneficially shift fecal metabolites and microbiota, and reduce blood lipids in adult dogs.

Effects of a Saccharomyces cerevisiae fermentation product-supplemented diet on fecal characteristics, oxidative stress, and blood gene expression of adult dogs undergoing transport stress.

Previously, a Saccharomyces cerevisiae fermentation product (SCFP) was shown to positively alter fecal microbiota, fecal metabolites, oxidative stress, and circulating immune cell function of adult dogs. The objective of this study was to measure the effects of SCFP on fecal characteristics, serum oxidative stress biomarkers, and whole blood gene expression of dogs undergoing transport stress. Sixteen adult pointer dogs [8M, 8F; mean age = 6.7 ± 2.1 yr; mean body weight (BW) = 25.5 ± 3.9 kg] were used in a randomized crossover design study. All dogs were fed a control diet for 4 wk, then randomly assigned to a control or SCFP-supplemented diet (formulated to include approximately 0.13% of the active SCFP ingredient) and fed to maintain BW for 11 wk. A 6-wk washout preceded the second 11-wk experimental period with dogs receiving opposite treatments. After 11 wk, fresh fecal and blood samples were collected before and after transport in a van for 45 min. Change from baseline data (i.e., before and after transport) were analyzed using the Mixed Models procedure of SAS 9.4, with P < 0.05 being significant and P < 0.10 being trends. Change in serum malondialdehyde concentrations increased (P < 0.05) and serum 8-isoprostane concentrations tended to increase (P < 0.10) in dogs fed SCFP, but decreased (P < 0.05) in control dogs after transport. Other serum markers were unaffected by diet during transport stress. Fecal dry matter percentage tended to be affected (P < 0.10) by diet during transport stress, being reduced in control dogs, but stable in dogs fed SCFP. Other fecal characteristics were unaffected by diet during transport stress. Genes associated with activation of innate immunity were impacted by diet in response to transport stress, with blood cyclooxygenase-2 and malondialdehyde mRNA expression being increased (P < 0.05) in control dogs, but stable or decreased in dogs fed SCFP. Expression of other genes was unaffected by diet during transport stress. These data suggest that the benefits of feeding a SCFP during transport stress may be mediated through suppression of innate immune cell activation.

Saccharomyces cerevisiae fermentation product (SCFP) is a yeast product containing bioactive fermentation metabolites, residual yeast cells, and yeast cell wall fragments. In this study, SCFP was investigated for its impacts on fecal characteristics and oxidative stress of dogs undergoing transport stress. Using a randomized crossover study design, 16 adult pointer dogs were used to compare changes in fecal characteristics, oxidative stress marker concentrations, and gene expression when fed a SCFP-supplemented diet or control diet. After transport, change in serum malondialdehyde concentrations increased and serum 8-isoprostane concentrations tended to increase in dogs fed SCFP, but decreased in control dogs. Fecal moisture percentage tended to be affected by diet during transport stress, being reduced in control dogs, but stable in dogs fed SCFP. Blood cyclooxygenase-2 and myeloperoxidase mRNA gene expression was affected by diet during transport stress, being increased in control dogs, but stable or decreased in dogs fed SCFP. In conclusion, these data suggest that the benefits of feeding a SCFP during transport stress may be mitigated through suppression of innate immune cell activation rather than through suppressing oxidative damage to lipids.

Effects of a Saccharomyces cerevisiae fermentation product-supplemented diet on circulating immune cells and oxidative stress markers of dogs.

Feeding Saccharomyces cerevisiae fermentation product (SCFP) has previously altered fecal microbiota, fecal metabolites, and immune function of adult dogs. The objective of this study was to investigate measures of skin and coat health, changes in circulating immune cell numbers and activity, antioxidant status, and oxidative stress marker concentrations of healthy adult dogs fed a SCFP-supplemented extruded diet. Sixteen adult English Pointer dogs (8 M, 8 F; mean age = 6.7 ± 2.1 yr; mean BW = 25.9 ± 4.5 kg) were used in a randomized crossover design study. All dogs were fed a control diet for 4 wk, then randomly assigned to either the control or SCFP-supplemented diet (0.13% of active SCFP) and fed to maintain BW for 10 wk. A 6-wk washout preceded the second 10-wk experimental period with dogs receiving opposite treatments. After baseline/washout and treatment phases, skin and coat were scored, and pre and postprandial blood samples were collected. Transepidermal water loss (TEWL), hydration status, and sebum concentrations were measured (back, inguinal, ear) using external probes. Oxidative stress and immune cell function were measured by ELISA, circulating immune cell percentages were analyzed by flow cytometry, and mRNA expression of oxidative stress genes was analyzed by RT-PCR. Change from baseline data was analyzed using the Mixed Models procedure of SAS 9.4. Sebum concentration changes tended to be higher (P < 0.10; inguinal, ear) in SCFP-fed dogs than in controls. TEWL change was lower (P < 0.05) on the back of controls, but lower (P = 0.054) on the ear of SCFP-fed dogs. Delayed-type hypersensitivity response was affected by diet and time post-inoculation. Other skin and coat measures and scores were not affected by diet. Changes in unstimulated lymphocytes and stimulated IFN-γ secreting T cells were lower (P < 0.05) in SCFP-fed dogs, while changes in stimulated T cells were lower (P < 0.05) in control-fed dogs. Upon stimulation, the percentage of cytotoxic T cells delta trended lower (P < 0.10) in SCFP-fed dogs. Change in serum superoxide dismutase concentrations was higher (P < 0.05) and change in catalase mRNA expression was lower (P < 0.05) in SCFP-fed dogs. All other measurements of immune cell populations, oxidative stress markers, and gene expression were unaffected by treatment. In conclusion, our data suggest that SCFP positively impacts indicators of skin and coat health of dogs, modulates immune responses, and enhances some antioxidant defense markers.

Saccharomyces cerevisiae fermentation product (SCFP) is a yeast product containing bioactive fermentation metabolites, residual yeast cells, and yeast cell wall fragments. In this study, SCFP was investigated for its impacts on immune health, oxidative stress, and skin and hair coat health in dogs. Using a randomized crossover study design, 16 adult pointer dogs were used to compare changes in immune cell numbers and activity, antioxidant status and oxidative stress marker concentrations, and skin and coat health markers when fed a SCFP-supplemented diet or control diet. Skin sebum concentrations increased in dogs fed SCFP, but transepidermal water loss changes depended on body location (ear, inguinal, or back). Delayed-type hypersensitivity response was affected by diet and time. Changes in unstimulated lymphocytes and stimulated IFN-γ secreting T cells were lower in SCFP-fed dogs, while changes in stimulated T cells were lower in control dogs. Changes in stimulated cytotoxic T cells tended to be lower in SCFP-fed dogs. Change in serum superoxide dismutase concentrations were higher, while change in catalase mRNA expression was lower in SCFP-fed dogs. In conclusion, our data suggest that SCFP positively impacts indicators of skin and coat health of dogs, modulates immune responses, and enhances some key antioxidant defense markers.