Fructooligosaccharides and Lactobacillus acidophilus modify gut microbial populations, total tract nutrient digestibilities and fecal protein catabolite concentrations in healthy adult dogs

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 ± 1.6 yr; body weight = 9.5 ± 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.

Characteristics of the Digestive Tract of Dogs and Cats

As for other mammals, the digestive system of dogs (facultative carnivores) and cats (obligate carnivores) includes the mouth, teeth, tongue, pharynx, esophagus, stomach, small intestine, large intestine, and accessory digestive organs (salivary glands, pancreas, liver, and gallbladder). These carnivores have a relatively shorter digestive tract but longer canine teeth, a tighter digitation of molars, and a greater stomach volume than omnivorous mammals such as humans and pigs. Both dogs and cats have no detectable or a very low activity of salivary α-amylase but dogs, unlike cats, possess a relatively high activity of pancreatic α-amylase. Thus, cats select low-starch foods but dogs can consume high-starch diets. In contrast to many mammals, the vitamin B12 (cobalamin)-binding intrinsic factor for the digestion and absorption of vitamin B12 is produced in: (a) dogs primarily by pancreatic ductal cells and to a lesser extent the gastric mucosa; and (b) cats exclusively by the pancreatic tissue. Amino acids (glutamate, glutamine, and aspartate) are the main metabolic fuels in enterocytes of the foregut. The primary function of the small intestine is to digest and absorb dietary nutrients, and its secondary function is to regulate the entry of dietary nutrients into the blood circulation, separate the external from the internal milieu, and perform immune surveillance. The major function of the large intestine is to ferment undigested food (particularly fiber and protein) and to absorb water, short-chain fatty acids (serving as major metabolic fuels for epithelial cells of the large intestine), as well as vitamins. The fermentation products, water, sloughed cells, digestive secretions, and microbes form feces and then pass into the rectum for excretion via the anal canal. The microflora influences colonic absorption and cell metabolism, as well as feces quality. The digestive tract is essential for the health, survival, growth, and development of dogs and cats.

Influence of dietary supplementation with new Lactobacillus strains on hematology, serum biochemistry, nutritional status, digestibility, enzyme activities, and immunity in dogs

Background and Aim

The use of antibiotics is associated with many side effects, with the development of bacterial resistance being particularly important. It has been found that dogs and their owners host similar resistant bacteria. This contributes to increased concurrent bacterial resistance and a possible trend of increased bacterial resistance in humans. Thus, using probiotics in dogs is an alternative option for preventing and reducing the transmission of bacterial resistance from dogs to humans. Probiotics are characterized by their potential to endure low pH levels and high concentrations of bile acids in the gastrointestinal tract. Lactobacilli are more acid-tolerant and resistant to bile acid, so they are ideal probiotics to be added to the canine diet. According to the previous studies, the benefits of Lactobacillus are a stable nutritional status and greater digestibility, along with improved fecal scores and reduced ammonia in dogs. However, no studies have been conducted with Lactobacillus plantarum CM20-8 (TISTR 2676), Lactobacillus acidophilus Im10 (TISTR 2734), Lactobacillus rhamnosus L12-2 (TISTR 2716), Lactobacillus paracasei KT-5 (TISTR 2688), and Lactobacillus fermentum CM14-8 (TISTR 2720), or their use in combination. Hence, the aim of this study was to examine the possible effects of the aforementioned Lactobacillus on hematological indices, nutritional status, digestibility, enzyme activities, and immunity in dogs. From the results, a new and safe strain of Lactobacillus may emerge for use as a probiotic in the future.

Materials and Methods

In this study, 35 dogs were allocated equally into seven groups: Group 1 received a basal diet (control), while Groups 2-7 received the same diet further supplemented with L. plantarum CM20-8 (TISTR 2676), L. acidophilus Im10 (TISTR 2734), L. rhamnosus L12-2 (TISTR 2716), L. paracasei KT-5 (TISTR 2688), L. fermentum CM14-8 (TISTR 2720), or a mixture of probiotics (L. plantarum, L. acidophilus, L. rhamnosus, L. paracasei, and L. fermentum), respectively. All probiotics were administered at a dose of 10⁹ colony-forming unit/dog for 28 days. Nutritional status, hematology, serum biochemistry, digestibility, enzyme activities, and immunity parameters were assessed.

Results

There were no differences among the groups in body weight, feed intake, body condition score, fecal score, and fecal dry matter on the different sampling days. The hematology and serum biochemical analyses showed a difference only in creatinine activity (p < 0.001), with higher values in group L. fermentum CM14-8 (TISTR 2720) and lower values in group L. paracasei KT-5 (TISTR 2688) than in controls. However, all measurements were within the normal laboratory reference ranges. Fecal characteristics (fecal ammonia and fecal pH), fecal digestive enzyme activities, serum immunoglobulin (IgG), and fecal IgA did not differ significantly among the groups (p > 0.05).

Conclusion

Lactobacillus plantarum CM20-8 (TISTR 2676), L. acidophilus Im10 (TISTR 2734), L. rhamnosus L12-2 (TISTR 2716), L. paracasei KT-5 (TISTR 2688), and L. fermentum CM14-8 (TISTR 2720), along with their mixture are safe and non-pathogenic additives for use as new probiotic strains of Lactobacillus in dogs. Although the new Lactobacillus strains had no effect on hematology, serum biochemistry, nutritional status, digestive enzyme activities, immunity, body weight, feed intake, or body condition scores in dogs, further studies should investigate the intestinal microbiota and the development of clinical treatments.

Effect of Limosilactobacillus reuteri ZJF036 on Growth Performance and Gut Microbiota in Juvenile Beagle Dogs

This experiment investigated the effects of Limosilactobacillus reuteri ZJF036 on growth performance, serum biochemical parameters, and gut microbiota in beagle dogs. Sixteen 75 ± 5-day-old healthy male beagles (4.51 ± 1.37 kg) were randomly divided into two groups; the experimental group (L1) and the control group (L0), and then fed with or without a basal diet containing L. reuteri ZJF036 (10⁹ CFU/g), respectively. The results showed that there was no significant difference in daily weight gain between the two groups (P > 0.05). However, we found that L. reuteri ZJF036 decreased Chao1 index and ACE index and increased the relative abundance of Firmicutes and Fusobacteria (P < 0.05) compared to the L0 group. In addition, we also found that the ratio of Firmicutes to Bacteroidetes was decreased in L1 group. Furthermore, the relative abundance of Lactobacillus increased, while that of Turicibacter and Blautia decreased in L1 group (P < 0.05). In conclusion, L. reuteri ZJF036 appeared to regulate the intestinal microbiota of beagle dogs. This study revealed the potential use of L. reuteri ZJBF036 as a probiotic supplement for beagle dogs.

Impact of Animal By-Products on Diet Digestibility and Fecal Quality in Beagle Dogs

In animal feeds and pet food, meat industry rendered by-products as a source of high-quality protein are commonly used. Among all rendered protein sources, poultry carcasses and neck meal are frequently used as ingredients in commercial pet foods due to their agreeable fatty acid and amino acid profiles, and they have no impact on the palatability of the diet. Nonetheless, it is unclear how poultry by-product meal affects companion animals regarding diet digestibility and fecal quality. This study either aimed to provide information on poultry by-product meal, including coarsely, finely, or very finely ground varieties, regarding their nutrient digestibility and characteristics of feces in dogs. One type of animal by-product meal was used in the three aforementioned particle sizes. Beagle dogs (n = 6; body weight, 16.6 kg ± 2.03) participated in a crossover experiment design. Each trial consisted of a five day adaptation period to the diet, and five days of fecal samples were collected and measured for individual apparent nutritional digestibility and fecal scores. The animal by-product supplementation in the diet of dogs was well accepted, with an acceptable percentage of apparent nutrient digestibility. Different particle sizes had no significant effect on the organic matter, crude protein, and crude fat digestibility as well as the fecal fatty acid concentrations. In addition, feces remained firm and well-formed and increased fecal dry matter. This indicates that poultry by-products should be taken into account as a potential dietary protein source in dog food.

Effects of commercial and traditional kefir supplementation on apparent total tract macronutrient digestibility and the fecal characteristics, metabolites, and microbiota of healthy adult dogs

Kefir is a fermented dairy beverage that has been consumed by humans for centuries, but poorly studied in pets. The objective of this study was to determine the effects of commercial or traditional kefir supplementation on apparent total tract macronutrient digestibility (ATTD) and fecal characteristics, microbiota populations, and metabolite and immunoglobulin (Ig) A concentrations of healthy adult dogs. Twelve healthy adult dogs (5.67 ± 1.72 yr, 7.27 ± 1.15 kg) were used in a replicated 3 × 3 Latin square design (n = 12/group). All dogs were fed a commercial diet and allotted to 1 of 3 treatments (60 mL/d): 2% reduced-fat milk treated with lactase [CNTL; 4.57E + 03 lactic acid bacteria (LAB) colony-forming units (CFU)/mL], commercial kefir (C-Kefir; 6.95E + 04 LAB CFU/mL), or traditional kefir brewed daily from 2% reduced-fat milk and kefir grains (T-Kefir; 1.79E + 09 LAB CFU/mL). The experiment was composed of three 28-d periods, with each consisting of a 22-d transition phase, a 5-d fecal collection phase, and 1 d for blood collection. Fecal samples were collected for determination of ATTD and fecal pH, dry matter, microbiota, and metabolite, and IgA concentrations. Data were analyzed using the Mixed Models procedure of SAS 9.4. The main effects of treatment were tested, with significance set at P ≤ 0.05 and trends set at P ≤ 0.10. Kefir products differed in microbial density and profile, but fecal microbiota populations were weakly impacted. Bacterial alpha diversity tended to be greater (P = 0.10) in dogs fed T-Kefir than those fed CNTL. Bacterial beta diversity analysis identified a difference (P < 0.0004) between dogs-fed CNTL and those fed C-Kefir. Dogs-fed C-Kefir tended to have a greater (P = 0.06) relative abundance of Fusobacteriota than those fed CNTL or T-Kefir. Dogs-fed T-Kefir had a greater (P < 0.0001) relative abundance of Lactococcus than those fed CNTL or C-Kefir. Dogs-fed T-Kefir also tended to have a lower (P = 0.09) relative abundance of Escherichia Shigella and greater (P = 0.09) relative abundance of Candidatus stoquefichus than dogs-fed CNTL or C-Kefir. Dogs-fed C-Kefir tended to have lower (P = 0.08) fecal valerate concentrations than those fed CNTL or T-Kefir. All other measures were unaffected by kefir treatments. Our results suggest that kefir supplementation had minor effects on the fecal microbiota populations and fecal metabolite concentrations of healthy adult dogs without impacting ATTD, fecal characteristics, or fecal IgA concentrations.

Effects of a milk oligosaccharide biosimilar on fecal characteristics, microbiota, and bile acid, calprotectin, and immunoglobulin concentrations of healthy adult dogs treated with metronidazole

In recent dog and cat experiments, a novel milk oligosaccharide biosimilar (GNU100) positively modulated fecal microbiota and metabolite profiles, suggesting benefits to gastrointestinal health. The objective of this study was to investigate the effects of GNU100 on the fecal characteristics, microbiota, and bile acid (BA) concentrations of healthy adult dogs treated with antibiotics. Twelve healthy adult female dogs (mean age: 3.74 ± 2.4 yr) were used in an 8-wk crossover design study (dogs underwent both treatments). All dogs were fed a control diet during a 2-wk baseline, then randomly allotted to 1 of 2 treatments (diet only or diet + 1% GNU100) for another 6 wk. From weeks 2 to 4, dogs were orally administered metronidazole (20 mg/kg BW) twice daily. Fecal scores were recorded daily and fresh fecal samples were collected at weeks 2, 4, 5, 6, and 8 for measurement of pH, dry matter, microbiota populations, and BA, immunoglobulin A, and calprotectin concentrations. On weeks 0, 4, and 8, blood samples were collected for serum chemistry and hematology analysis. All data were analyzed as repeated measures using the Mixed Models procedure of SAS version 9.4, with significance considered P < 0.05. Metronidazole increased (P < 0.0001) fecal scores (looser stools) and modified (P < 0.05) fecal microbiota and BA profiles. Using qPCR, metronidazole reduced fecal Blautia, Fusobacterium, Turicibacter, Clostridium hiranonis, and Faecalibacterium abundances, and increased fecal Streptococcus and Escherichia coli abundances. DNA sequencing analysis demonstrated that metronidazole reduced microbial alpha diversity and influenced the relative abundance of 20 bacterial genera and families. Metronidazole also increased primary BA and reduced secondary BA concentrations. Most antibiotic-induced changes returned to baseline by week 8. Fecal scores were more stable (P = 0.01) in GNU100-fed dogs than controls after antibiotic administration. GNU100 also influenced fecal microbiota and BA profiles, reducing (P < 0.05) the influence of metronidazole on microbial alpha diversity and returning some fecal microbiota and secondary BA to baseline levels at a quicker (P < 0.05) rate than controls. In conclusion, our results suggest that GNU100 supplementation provides benefits to dogs treated with antibiotics, providing more stable fecal scores, maintaining microbial diversity, and allowing for quicker recovery of microbiota and secondary BA profiles which play an essential role in gut health.

Digestibility of a Lignocellulose Supplemented Diet and Fecal Quality in Beagle Dogs

Lignocellulose (LC) might be used as a substitute fiber source for dogs as a strategy to decrease energy density and enhance gastrointestinal functionality. The objective of the present study was to compare the effects of including different levels of LC on apparent nutrient digestibility and fecal parameters (dry matter (DM), fecal score, and daily fecal output), as well as fecal fatty acid concentrations. Four diets were tested: control diet (no supplementation of LC; LC0), and three control diets diluted with increasing levels of LC: 1, 2, and 4% (LC1, LC2, and LC4). Six Beagle dogs (BW 17.1 kg ± 1.22) participated in a crossover experimental design. Before each experimental period, five days were used as a wash-out period. The fecal consistency was scored based on a 5-point scale (1 = very hard; 2 = solid, well-formed “optimum”; 3 = soft, still formed; 4 = pasty, slushy; and 5 = watery diarrhea). The results demonstrated that the organic matter apparent digestibility (p = 0.01) and nitrogen-free extract (NFE) (p < 0.01) was significantly lower for dogs fed LC4 compared to those fed LC0. Dogs fed LC2 and LC4 had a lower fecal consistency score (2.39 and 2.18, respectively; p < 0.05). The fecal DM was significantly the highest (p < 0.01), and the daily fecal output on fresh matter was lower (p < 0.05) when dogs were fed the LC4 diet compared with the LC0 diet. Including LC at 1% in the diet resulted in significantly higher fecal acidic pH levels. However, no differences among treatments were noted regarding fecal fatty acid concentrations.

Impacts of Various Nutraceutical Milk Replacer Supplements on the Health and Performance of High-Risk Holstein Calves

The objectives of this study were to determine the impacts of supplementing various nutraceuticals in milk replacers, including a blend of probiotics, β-glucan extract, mannanoligosaccharide extract, or a non-immunoglobulin rich extract, from colostrum on the performance and health of high-risk calves and to determine carry-over effects into the immediate post-weaned period. One hundred bull calves were acquired from a local calf ranch within 24 h of birth and randomly assigned to one of five dietary treatments added to milk replacer only: (1) Control (CON), no additive; (2) Immu-PRIME (ImmPr), 1.5 g/d ImmPr first 3 d only (Sterling Technology, Brookings, SD, USA); (3) Beta glucan (BG), 1 g/d BG extract (ImmuOligo, Irvine, CA, USA); (4) Mannanoligosaccharide + Bacillus subtilis (MOS+Bs), 3 g/d CEREVIDA EXCELL-M + 4 x 109 CFU/d Bacillus subtilis (MB Nutritional Sciences, Lubbock, TX, USA); and (5) PROVIDA CALF (PRO), proprietary blend of 2 x 109 CFU/d of a Lactobacillus casei and an Enterococcus faecium + 2 x 109 CFU/d Saccharomyces cerevisiae (MB Nutritional Sciences, Lubbock, TX, USA). Calves were weaned at d 56, comingled, and treatment carry-over effects evaluated through d 84. Starter intake was measured daily and BW weekly. Peripheral blood samples were collected and analyzed for hematology and serum was analyzed for haptoglobin concentrations. Polymorphonuclear leukocyte (PMNL) function was assessed through surface L-selectin expression, phagocytic, and oxidative burst activities against Escherichia coli. Data were analyzed using Proc Mixed in SAS (SAS 9.4, Cary, NC). The BG calves consumed the most starter from d 1 to 28 and pre-weaned average daily gain was greater for both the PRO and BG when compared to the CON group. There was a tendency for BG, MOS+Bs, and PRO to have reduced serum haptoglobin throughout the study. Total leukocyte, neutrophil, and lymphocyte counts were reduced among MOS+Bs calves, whereas BG calves tended to have the greatest neutrophil:lymphocyte ratio. Oxidative burst function for PMNL was reduced among BG and PRO treatments, suggesting a decreased need for neutrophil function. Supplementing BG, MOS+Bs, and PRO all influenced the performance and health of high-risk calves, but mechanistically appear to be different.

Nutrient Digestibility and Fecal Quality in Beagle Dogs Fed Meat and Bone Meal Added to Dry Food

Meat and bone meal (MBM) is one animal by-product used in pets. This study purposed to provide information on MBM including either coarsely (MBMc) or finely (MBMf) ground with regard to diet digestibility and fecal characteristics in dogs. Three different levels of MBM (6%, 12% and 24%) of each grinding form (MBM6, MBM12 and MBM24) were added to a basic diet. Six Beagle dogs (body weight 16.7 kg ± 0.42) participated in a Latin Square experiment. Each trial began with the animals adapting to the food for a five-day period, followed by five days of fecal collection. The feed particle size had no effect on the apparent digestibility of organic matter, crude protein and crude fat. The fecal score was significantly affected by the particle size × level interaction among treatments (p < 0.0001). It was noted that the different particle sizes or levels of MBM as main effects had no significant effect on the fecal fatty acid concentrations. These findings suggest that using coarse or fine grinding even including MBM up to 24% in dog diets does not affect the apparent digestibility of protein nor fecal quality negatively in our experimental study.

Influence of Probiotic Supplementation on Health Status of the Dogs: A Review

Most commonly, pet dogs suffer from gastrointestinal (GI) diseases due to careless eating behaviors, such as eating food other than dog food; excess or insufficient nutrient intake of food leading to malnutrition, which could be harmful to dogs; a lack of digestive enzymes; food intolerance or allergies; infections; and/or breed-related hypersensitivities. Probiotics are live microorganisms that deliver health benefits to the host when administrated in an adequate amount. The possible mechanism behind probiotics’ beneficial effects could be their positive regulation of the host’s intestinal microbiota. Probiotics are reported to have therapeutic properties against canine GI and other diseases. The most suitable dosages and applications of probiotics have not been evaluated extensively. The present review summarizes current knowledge regarding the benefits of probiotics and the changes in canine microbiota during probiotic interventions. This literature review provides clinical evidence for probiotics’ beneficial effects in preventing or treating canine ill-health conditions. Based on current knowledge, subsequent researchers could develop or improve probiotics-based canine pharmacological products.

Altered fecal microbiota, IgA, and fermentative end-products in adult dogs fed prebiotics and a nonviable Lactobacillus acidophilus

A study investigating the use of a nonviable Lactobacillus acidophilus (NVL: Culbac; TransAgra, Storm Lake, IA) and a mixed prebiotic (MP) blend (beet pulp, fructooligosaccharide (FOS), mannanoligosaccharide (MOS), inulin, and kelp) was done to evaluate changes in fecal microbiota, fermentative end products, and gut immune health in healthy female and male adult Beagle dogs (n = 24; 5.74 ± 2.18 yr; 9.30 ± 1.32 kg). The study protocol was first approved by the facility's Institutional Animal Care and Use Committee (Summit Ridge Farms; Susquehanna, PA) and followed throughout. Each of four test diets (control, NVL, MP, and MP + NVL [formulated to crude protein 25%, crude fat 14%, crude fiber 10% as-fed]) was fed once daily to maintain body weight for 21 d in a randomized-crossover design (four treatment periods and four washout periods). Fecal samples were collected on days 0 and 21 only for immunoglobulin A (IgA) and microbiota evaluation (16S rRNA V4 region and qPCR for Escherichia coli and Bifidobacterium), and fecal fermentative end-products and fecal pH were assessed only on day 21. Over the test periods, apparent total tract nutrient digestibility and stool quality were assessed. Data were analyzed by ANOVA (SAS v9.4, Cary, NC) or Kruskal-Wallis for between-diet effects, and paired t-test or Wilcoxon for time effects. Statistical significance was set at P ≤ 0.05. Apparent total tract nutrient digestibility revealed feeding MP-containing diets resulted in lower (P < 0.05) crude protein and fat digestibility vs. control and NVL diets. When dogs were fed MP, they had lower (P < 0.05) fecal pH compared with control and NVL diets, whereas fecal pH was lower in (P < 0.05) MP + NVL- vs. NVL-fed dogs. Fecal E. coli was (P < 0.05) lower at day 21 vs. day 0 when dogs were fed MP. Fecal Fusobacterium spp. was lower (P < 0.05) in both MP diets vs. control. Fecal Lactobacillus spp. increased (P < 0.05) from baseline with MP. Both diets with MP elicited greater (P < 0.05) fecal acetate and propionate concentration vs. control diet. At day 21, fecal IgA was greater (P < 0.05) in MP and MP + NVL compared with NVL diet. Only when dogs were fed MP did they have increased (P < 0.05) fecal IgA from day 21 vs. day 0. The MP + NVL diet decreased (P < 0.05) fecal isovalerate, isobutyrate, phenol, and indole vs. control. Overall, the MP elicited the most changes on microbiota, fermentative end-products, and IgA. Further investigation into NVL's gut health benefits is warranted.

Effects of Saccharomyces cerevisiae cell wall addition on feed digestibility, fecal fermentation and microbiota and immunological parameters in adult cats

Background

This study aimed to evaluate the effects of increasing dosages of a commercial product composed by Saccharomyces cerevisiae yeast (YAM), with active metabolites, which are beta glucans, nucleotides, organic acids, polyphenols, amino acids, vitamins and minerals (Original XPC^tm, Diamond V, IOWA, USA) added to a commercially available dry cat food. Apparent digestibility of dietary nutrients, fecal microbiota, fecal fermentation products and immunological parameters were evaluated. Twenty-seven healthy cats of mixed sexes, with a mean body weight of 4.19 ± 0.83 kg and a mean age of 9.44 ± 5.35 years were distributed by age in an unbalanced randomized block design, consisting of three experimental treatments: CD (control diet), YAM 0.3 (control diet with 0.3% yeast with active metabolites) and YAM 0.6 (control diet with 0.6% yeast with active metabolites).

Results

The inclusion of the additive elevated the apparent digestibility of crude fiber (p = 0.013) and ash (p < 0.001) without interfering feed consumption, fecal production and fecal characteristics. Regarding fermentation products present in the feces, prebiotic inclusion increased lactic acid concentration (p = 0.004) while reducing isovaleric acid (p = 0.014), only in the treatment YAM 0.3. No differences were noticed on biogenic amines (BA), fecal pH, ammonia concentration, total and individuals short-chain fatty acids (SCFA) and total and individuals branched-chain fatty acids (BCFA) (except isovaleric acid in YAM 0.3). As regards to fecal microbiota, prebiotic inclusion has resulted in the reduction of Clostridium perfringens (p = 0.023). No differences were found in the immunological parameters evaluated.

Conclusion

It can be concluded that the additive, at the levels of inclusion assessed shows prebiotic potential and it has effects on fecal fermentation products and microbiota without interfering on crude protein and dry matter digestibility. More studies evaluating grater inclusion levels of the prebiotic are necessary to determine optimal concentration.

Evaluation of graded levels of Bacillus coagulans GBI-30, 6086 on apparent nutrient digestibility, stool quality, and intestinal health indicators in healthy adult dogs

Bacillus coagulans GBI-30, 6086 is a commercially available spore-forming non-toxigenic microorganism approved for use in dog foods with high resiliency to stresses associated with commercial manufacturing. The objectives of this research were to examine the effect of B. coagulans on stool quality, nutrient digestibility, and intestinal health markers in healthy adult dogs. Extruded diets containing graded levels of B. coagulans applied either to the base ration before extrusion or to the exterior of the kibble as a topical coating after extrusion were randomly assigned to 10 individually housed adult beagle dogs (7 castrated males and 3 spayed females) of similar age (5.75 ± 0.23 yr) and body weight (12.3 ± 1.5 kg). The study was designed as a 5 × 5 replicated Latin square with 16-d adaptation followed by 5-d total fecal collection for each period. Five dietary treatments were formulated to deliver a dose of 0-, 6-, 7-, 8-, and 9-log10 colony-forming units (CFU) per dog per day for the control (CON), extruded B. coagulans (PEX), and low, moderate, and high B. coagulans coating levels (PCL, PCM, and PCH), respectively. Food-grade TiO2 was added to all diets at a level of 0.4% to serve as an indigestible dietary marker for digestibility calculations. Data were analyzed using a mixed model through SAS (version 9.4, SAS Institute, Inc., Cary, NC) with treatment as a fixed effect and room (i.e., replicate), period, and dog(room) as random effects. Apparent total tract digestibility of organic matter, crude protein, crude fat, and gross energy calculated by the marker method were numerically greatest for dogs fed the 9-log10 dose treatment with increases (P < 0.05) observed in gross energy and organic matter digestibility compared with the negative control. No significant differences were observed in food intake, stool quality, fecal pH, fecal ammonia, fecal short-chain fatty acids, or branched-chain fatty acids for the extruded B. coagulans treatment (PEX) or the coated B. coagulans treatments (PCL, PCM, and PCH) compared with CON. These results suggest that B. coagulans has a favorable impact on nutrient digestibility and no apparent adverse effects when added to extruded diets at a daily intake level of up to 9-log10 CFU in healthy adult dogs.

Nutrient digestibility and fecal characteristics, microbiota, and metabolites in dogs fed human-grade foods

Human-grade (HG) pet foods are commercially available, but they have not been well studied. Our objective was to determine the apparent total tract digestibility (ATTD) of HG pet foods and evaluate their effects on fecal characteristics, microbiota, and metabolites, serum metabolites, and hematology of dogs. Twelve dogs (mean age = 5.5 ± 1.0; BW = 11.6 ± 1.6 kg) were used in a replicated 4 × 4 Latin square design (n = 12/treatment). The diets included 1) Chicken and Brown Rice Recipe (extruded; Blue Buffalo); 2) Roasted Meals Tender Chicken Recipe (fresh; Freshpet); 3) Beef and Russet Potato Recipe (HG beef; JustFoodForDogs); and 4) Chicken and White Rice Recipe (HG chicken; JustFoodForDogs). Each period consisted of 28 d, with a 6-d diet transition phase, 16 d of consuming 100% of the diet, a 5-d phase for fecal collection, and 1 d for blood collection. All data were analyzed using the Mixed Models procedure of SAS 9.4. Dogs fed the extruded diet required a higher (P < 0.05) daily food intake (dry matter basis, DMB) to maintain BW. The ATTD of dry matter (DM), organic matter (OM), energy, and acid-hydrolyzed fat (AHF) were greater (P < 0.05) in dogs fed the HG diets than those fed the fresh diet, and greater (P < 0.05) in dogs fed the fresh diet than those fed the extruded diet. Crude protein ATTD was lower (P < 0.05) for dogs fed the extruded diet than those fed all other diets. Dogs fed the extruded diet had greater (P < 0.05) fecal output (as-is; DMB) than dogs fed fresh (1.5-1.7 times greater) or HG foods (2.0-2.9 times greater). There were no differences in fecal pH, scores, and metabolites, but microbiota were affected by diet. Dogs fed HG beef had higher (P < 0.05) relative abundance of Bacteroidetes and lower (P < 0.05) relative abundance of Firmicutes than dogs fed the fresh or HG chicken diets. The Actinobacteria, Fusobacteria, Proteobacteria, and Spirochaetes phyla were unchanged (P > 0.05), but diet modified the relative abundance of nearly 20 bacterial genera. Similar to previous reports, these data demonstrate that the fecal microbiota of dogs fed HG or fresh diets is markedly different than those consuming extruded diets, likely due to ingredient, nutrient, and processing differences. Serum metabolites and hematology were not greatly affected by diet. In conclusion, the HG pet foods tested resulted in significantly reduced fecal output, were highly digestible, maintained fecal characteristics, serum chemistry, and hematology, and modified the fecal microbiota of dogs.

Uso do gérmen de milho desengordurado, com e sem adição de um complexo enzimático, em dietas para cães

RESUMO Objetivou-se avaliar o coeficiente de digestibilidade aparente (CDA) dos nutrientes, a palatabilidade das dietas e as características fecais de cães alimentados com uma dieta controle e uma dieta contendo 20% de gérmen desengordurado (GD), com e sem adição de complexo enzimático (amilase, xilanase, betaglucanase e mananase). Para o experimento de digestibidade e das características fecais, foram utilizados 12 cães adultos, distribuídos em delineamento em blocos ao acaso, em esquema fatorial 2 x 2 (dieta x enzima). O segundo experimento avaliou a palatabilidade, por meio da primeira escolha e da razão de ingestão (RI) da dieta DC vs. 20% de GD, utilizando-se 16 cães. O teste de palatabilidade contou com três dias consecutivos, totalizando 48 repetições. A dieta com inclusão de 20% de GD teve os menores valores de CDA da MS, da EB e da EM (P<0,05). A inclusão do complexo enzimático melhorou o CDA da MS, da EB e da EM (P<0,05). Não foram observadas diferenças nas características fecais (P>0,05). Em relação à palatabilidade, os cães preferiram a dieta 20% de GD, tanto na primeira escolha como na RI (P<0,05). A inclusão de enzimas às dietas melhora a digestibilidade dos nutrientes e da EM, sendo um aditivo com potencial uso na alimentação de cães.

Effect of a novel animal milk oligosaccharide biosimilar on macronutrient digestibility and gastrointestinal tolerance, fecal metabolites, and fecal microbiota of healthy adult cats

GNU100 is a novel animal milk oligosaccharide (AMO) biosimilar. In a recent in vitro fermentation study, GNU100 was shown to be fermentable by feline gastrointestinal microbiota and lead to increased short-chain fatty acid production. Our objectives herein were to evaluate the palatability, safety, and gastrointestinal tolerance of GNU100 in healthy adult cats. Exploratory end-points were measured to assess utility. In study 1, 20 adult cats were used to test the palatability of diets containing 0% or 1% GNU100. In study 2, 32 (mean age = 1.9 yr; mean body weight = 4.6 kg) male (n = 12) and female (n = 20) adult cats were used in a completely randomized design. After a 2-wk baseline, cats were assigned to one of the following treatment groups and fed for 26 wk: control (CT, no GNU100), low dose (LD, 0.5% GNU100), medium dose (MD, 1.0% GNU100), and high dose (HD, 1.5% GNU100). On weeks 2, 4, and 26, fresh fecal samples were collected for the measurement of stool quality and immune and inflammatory markers and on weeks 2 and 4 for microbiota and metabolites. On week 4, total feces were collected to measure apparent total tract macronutrient digestibility. On weeks 2, 4, and 26, blood samples were collected for serum chemistry, hematology, and inflammatory marker measurement. The palatability test showed that 1% GNU100 was strongly preferred (P < 0.05), with GNU100 having a 17.6:1 consumption ratio compared with control. In the long-term study, all cats remained healthy, without any signs of gastrointestinal intolerance or illness. All diets were well accepted, resulting in similar (P > 0.05) food intake, fecal characteristics, immunoglobulin A, and calprotectin, and dry matter, organic matter, fat, and crude protein digestibilities. Fecal butyrate was greater (P = 0.02) in cats fed HD than cats fed LD or MD. Fecal indole was lower (P = 0.02) in cats fed HD than cats fed LD. Cats fed CT had a higher (P = 0.003) relative abundance of Actinobacteria than cats fed LD. The relative abundance of Peptococcus was impacted by diet and time. At 4 wk, Campylobacter was lower in fecal samples of cats fed HD. Overall, the data suggest that dietary GNU100 supplementation was highly palatable, well tolerated, did not cause detrimental effects on fecal quality or nutrient digestibility, increased fecal butyrate concentrations, and reduced fecal indole concentrations, supporting the safety of GNU100 for inclusion in feline diets and suggesting potential benefits on gastrointestinal health of cats.

Graded dietary resistant starch concentrations on apparent total tract macronutrient digestibility and fecal fermentative end products and microbial populations of healthy adult dogs

Resistant starch (RS) is fermentable by gut microbiota and effectively modulates fecal short-chain fatty acid concentrations in pigs, mice, and humans. RS may have similar beneficial effects on the canine gut but has not been well studied. The objective of this study was to evaluate the effects of 0%, 1%, 2%, 3%, and 4% dietary RS (Hi-maize 260) on apparent total tract macronutrient digestibility, fecal characteristics, fermentative end-product concentrations, and microbiota of healthy adult dogs. An incomplete 5 × 5 Latin square design with seven dogs and five experimental periods was used, with each treatment period lasting 21 d (days 0 to 17 adaptation; days 18 to 21 fresh and total fecal collection) and each dog serving as its own control. Seven dogs (mean age = 5.3 yr; mean body weight = 20 kg) were randomly allotted to one of five treatments formulated to be iso-energetic and consisting of graded amounts of 100% amylopectin cornstarch, RS, and cellulose and fed as a top dressing on the food each day. All dogs were fed the same amount of a basal diet throughout the study, and fresh water was offered ad libitum. The basal diet contained 6.25% RS (dry matter [DM] basis), contributing approximately 18.3 g of RS/d based on their daily food intake (292.5 g DM/d). Data were evaluated for linear and quadratic effects using SAS. The treatments included 0%, 1%, 2%, 3%, and 4% of an additional RS source. Because Hi-maize 260 is approximately 40% digestible and 60% indigestible starch, the dogs received the following amounts of RS daily: 0% = 18.3 g (18.3 + 0 g), 1% = 20.1 g (18.3 + 1.8 g), 2% = 21.9 g (18.3 + 3.6 g), 3% = 23.7 g (18.3 + 5.4 g), and 4% = 25.5 g (18.3 + 7.2 g). Apparent total tract DM, organic matter, crude protein, fat, and gross energy digestibilities and fecal pH were linearly decreased (P < 0.05) with increased RS consumption. Fecal output was linearly increased (P < 0.05) with increased RS consumption. Fecal scores and fecal fermentative end-product concentrations were not affected by RS consumption. Although most of the fecal microbial taxa were not altered, Faecalibacterium were increased (P < 0.05) with increased RS consumption. The decrease in fecal pH and increase in fecal Faecalibacterium would be viewed as being beneficial to gastrointestinal health. Although our results seem to indicate that RS is poorly and/or slowly fermentable in dogs, the lack of observed change may have been due to the rather high level of RS contained in the basal diet.

Duration of Prebiotic Intake Is a Key-Factor for Diet-Induced Modulation of Immunity and Fecal Fermentation Products in Dogs

Prebiotics promote health benefits, however, there is no consensus on the minimal intake period required in order to obtain good results. This study evaluated the effect of the time of ingestion of prebiotics on fecal fermentation products and immunological features in dogs. Twenty-four adult dogs were randomly distributed in a block design with six groups and four treatments. Diet and intake period were variation factors. Diets were either a control diet without the addition of prebiotic (CO) or with the inclusion of 1% of a commercial product containing a minimum of 0.38% galactooligosaccharides (GOS), 0.5% (B1) or 1% (B2) of a prebiotic blend. Time variable was set at 30 and 60 days for evaluation of immunity and gut health. Results were analyzed in the Statistical Analysis System software (SAS), version 9.4, considering the repeated measures over time design, and means were compared by the Tukey test and p < 0.05 was significant. Propionic acid was the only variable that had an interaction effect, with reduction of this metabolite in treatment B2 in the period of 60 days. At T60, concentrations of immunoglobulin A, lactic acid, and pH in the feces increased (p < 0.05) in all treatments regardless of prebiotic inclusion or not. GOS increased fecal score and lactic acid concentrations. Therefore, a 60-day intake period of a prebiotic blend was not sufficient to modulate fecal and immune variables and higher concentrations of a single prebiotic would be more relevant for results.

Lactobacillus species in drinking water had no main effects on sulphur compounds from manure, egg quality, and selected serum parameters of second cycle hens

1. The aim of this study was to investigate the effects of a combined probiotic product (Lactobacillus paracasei, L. plantarum, and L. rhamnosus) on egg quality, sulphur compounds in manure and serum biochemistry of second cycle hens. 2. A total of 48 White Leghorn hens, at 52- to 54 weeks of age, were treated in a completely randomised design with water containing 0 or 1.8375 × 10¹⁰ cfu/l of probiotics for 8 weeks. 3. Probiotic supplementation did not affect egg quality. Albumen height and Haugh units were in general lowest in week 2 and highest in week 6. 4. For manure and serum parameters, water with or without probiotics produced statistically similar effects. An interacting trend for increasing concentrations of methyl mercaptan in manure was noted for probiotics x week, and should be further investigated. The week of supplementation significantly affected hydrogen sulphide, dimethyl sulphide, and triglycerides.

The Effects of Nutrition on the Gastrointestinal Microbiome of Cats and Dogs: Impact on Health and Disease

The gastrointestinal (GI) microbiome of cats and dogs is increasingly recognized as a metabolically active organ inextricably linked to pet health. Food serves as a substrate for the GI microbiome of cats and dogs and plays a significant role in defining the composition and metabolism of the GI microbiome. The microbiome, in turn, facilitates the host's nutrient digestion and the production of postbiotics, which are bacterially derived compounds that can influence pet health. Consequently, pet owners have a role in shaping the microbiome of cats and dogs through the food they choose to provide. Yet, a clear understanding of the impact these food choices have on the microbiome, and thus on the overall health of the pet, is lacking. Pet foods are formulated to contain the typical nutritional building blocks of carbohydrates, proteins, and fats, but increasingly include microbiome-targeted ingredients, such as prebiotics and probiotics. Each of these categories, as well as their relative proportions in food, can affect the composition and/or function of the microbiome. Accumulating evidence suggests that dietary components may impact not only GI disease, but also allergies, oral health, weight management, diabetes, and kidney disease through changes in the GI microbiome. Until recently, the focus of microbiome research was to characterize alterations in microbiome composition in disease states, while less research effort has been devoted to understanding how changes in nutrition can influence pet health by modifying the microbiome function. This review summarizes the impact of pet food nutritional components on the composition and function of the microbiome and examines evidence for the role of nutrition in impacting host health through the microbiome in a variety of disease states. Understanding how nutrition can modulate GI microbiome composition and function may reveal new avenues for enhancing the health and resilience of cats and dogs.

Development and validation of the Simulator of the Canine Intestinal Microbial Ecosystem (SCIME)1

Whereas a wide variety of in vitro models have been developed and validated to assess the effect of specific food ingredients on the human gut microbiome, such models have only been developed and applied to a limited extent for companion animals. Since the use of pre- and probiotics to improve gut health is an emerging research topic in the field of companion animals and as dogs are often used as laboratory animals in developing and testing of pharmaceuticals, the current study aimed to establish an adequate canine in vitro model. This consisted of a four-stage reactor composed of a stomach and small intestinal compartment followed by a proximal and distal colon. This semi-continuous gastrointestinal tract model allowed a long-term, region-dependent, and pH-controlled simulation of the colon-associated microbial community of dogs. Upon reaching a functional steady state, the simulated canine microbial community composition proved to be representative of the in vivo situation. Indeed, the predominant bacterial phyla present in the in vitro proximal and distal colon corresponded with the main bacterial phyla detected in the fecal material of the dogs, resulting in an average community composition along the simulated canine gastrointestinal tract of 50.5% Firmicutes, 34.5% Bacteroidetes, 7.4% Fusobacteria, 4.9% Actinobacteria, and 2.7% Proteobacteria. A parallel in vivo-in vitro comparison assessing the effects of fructooligosaccharides (FOS) on the canine microbial community composition showed a consistent stimulation of Lactobacillus concentrations in the in vivo fecal samples as well as in the in vitro canine gut model. Furthermore, the in vitro platform provided additional insights about the prebiotic effect of FOS supplementation of dogs, such as a reduced abundance of Megamonas spp. which are only present in very low abundance in in vivo fecal samples, indicating an interesting application potential of the developed canine in vitro model in research related to gastrointestinal health of dogs.

Relationships Between Gut Microbiota, Metabolome, Body Weight, and Glucose Homeostasis of Obese Dogs Fed with Diets Differing in Prebiotic and Protein Content

Obesity is a major issue in pets and nutritional strategies need to be developed, like promoting greater protein and fiber intake. This study aimed to evaluate the effects of dietary protein levels and prebiotic supplementation on the glucose metabolism and relationships between the gut, microbiota, metabolome, and phenotype of obese dogs. Six obese Beagle dogs received a diet containing 25.6% or 36.9% crude protein, with or without 1% short-chain fructo-oligosaccharide (scFOS) or oligofructose (OF), in a Latin-square study design. Fecal and blood samples were collected for metabolite analysis, untargeted metabolomics, and 16S rRNA amplicon sequencing. A multi-block analysis was performed to build a correlation network to identify relationships between fecal microbiota, metabolome, and phenotypic variables. Diets did not affect energy homeostasis, but scFOS supplementation modulated fecal microbiota composition and induced significant changes of the fecal metabolome. Bile acids and several amino acids were related to glucose homeostasis while specific bacteria gathered in metavariables had a high number of links with phenotypic and metabolomic parameters. It also suggested that fecal aminoadipate and hippurate act as potential markers of glucose homeostasis. This preliminary study provides new insights into the relationships between the gut microbiota, the metabolome, and several phenotypic markers involved in obesity and associated metabolic dysfunctions.

RapidAIM: a culture- and metaproteomics-based Rapid Assay of Individual Microbiome responses to drugs

BACKGROUND

Human-targeted drugs may exert off-target effects or can be repurposed to modulate the gut microbiota. However, our understanding of such effects is limited due to a lack of rapid and scalable assay to comprehensively assess microbiome responses to drugs. Drugs and other compounds can drastically change the overall abundance, taxonomic composition, and functions of a gut microbiome.

RESULTS

Here, we developed an approach to screen compounds against individual microbiomes in vitro, using metaproteomics to both measure absolute bacterial abundances and to functionally profile the microbiome. Our approach was evaluated by testing 43 compounds (including 4 antibiotics) against 5 individual microbiomes. The method generated technically highly reproducible readouts, including changes of overall microbiome abundance, microbiome composition, and functional pathways. Results show that besides the antibiotics, the compounds berberine and ibuprofen inhibited the accumulation of biomass during in vitro growth of the microbiota. By comparing genus and species level-biomass contributions, selective antibacterial-like activities were found with 35 of the 39 non-antibiotic compounds. Seven of the compounds led to a global alteration of the metaproteome, with apparent compound-specific patterns of functional responses. The taxonomic distributions of altered proteins varied among drugs, i.e., different drugs affect functions of different members of the microbiome. We also showed that bacterial function can shift in response to drugs without a change in the abundance of the bacteria.

CONCLUSIONS

Current drug-microbiome interaction studies largely focus on relative microbiome composition and microbial drug metabolism. In contrast, our workflow enables multiple insights into microbiome absolute abundance and functional responses to drugs. The workflow is robust, reproducible, and quantitative and is scalable for personalized high-throughput drug screening applications.

Dietary supplementation of a fiber-prebiotic and saccharin-eugenol blend in extruded diets fed to dogs

Prebiotics and dietary fibers are nondigestible ingredients that may confer benefits to the host by selectively stimulating beneficial intestinal bacteria and microbial-derived metabolites that support gut and host health. This experiment evaluated the effects of a blend of prebiotics and dietary fibers on apparent total tract digestibility (ATTD) and fecal metabolites related to gastrointestinal health in adult dogs. Four diets containing either 5% cellulose (control; CT), 5% dietary fiber and prebiotic blend (FP), 0.02% saccharin and eugenol (SE), or 5% fiber blend plus 0.02% saccharin and eugenol (FSE) were formulated to meet or exceed the AAFCO (2017) nutritional requirements for adult dogs. Eight adult female beagles (mean age 4.2 ± 1.1 yr; mean BW = 10.8 ± 1.4 kg; mean BCS = 5.8 ± 0.6) were randomly assigned to 1 of the 4 dietary treatments using a replicated 4 × 4 Latin square design. Each experimental period consisted of 14 d (10 d of diet adaptation and 4 d of total and fresh fecal and total urine collection). All animals remained healthy throughout the study, with serum metabolites being within reference ranges for adult dogs. All diets were well accepted by the dogs, resulting in similar (P > 0.05) daily food intakes among treatments. Likewise, fecal output and scores did not differ (P > 0.05) among dietary treatments, with the latter being within the ideal range (2.5-2.9) in a 5-point scale. All diets were highly digestible and had similar (P > 0.05) ATTD of dry matter (81.6%-84.4%), organic matter (86.4%-87.3%), and crude protein (86.6%-87.3%). However, total dietary fiber (TDF) digestibility was greater for dogs fed the FSE diet (P < 0.05) in contrast with dogs fed the CT and SE diets, whereas dogs fed FP diets had intermediate TDF digestibility, but not different from all other treatments. Fecal acetate and propionate concentrations were greater (P < 0.05) for dogs fed FP and FSE diets. Fecal concentrations of isobutyrate and isovalerate were greater for dogs fed CT (P < 0.05) compared with dogs fed the other three treatments. No shifts in fecal microbial richness and diversity were observed among dietary treatments. Overall, the data suggest that dietary supplementation of fiber and prebiotic blend was well tolerated by dogs, did not cause detrimental effects on fecal quality or nutrient digestibility, and resulted in beneficial shifts in fecal metabolites that may support gut health.

Altered microbiota, fecal lactate, and fecal bile acids in dogs with gastrointestinal disease

The intestinal microbiota plays an important role in health and disease and produces, through fermentative reactions, several metabolic products, such as lactate, that can affect the host. The microbiota also interacts with and metabolizes compounds produced by the host, such as primary bile acids. Lactate and bile acids (BA) are of particular interest in gastrointestinal diseases because they have been associated with metabolic acidosis and bile acid diarrhea, respectively. The objectives of this study were to validate an enzymatic assay to quantify D-, L-, and total lactate in canine feces, and to characterize fecal lactate and BA concentrations as well as bacterial abundances in healthy dogs and dogs with gastrointestinal diseases. Fecal samples were collected from 34 healthy dogs, 15 dogs with chronic enteropathy (CE), and 36 dogs with exocrine pancreatic insufficiency (EPI). Lactate was quantified with an enzymatic assay, BA with gas chromatography-mass spectrometry, and 11 bacterial groups with qPCR. A fecal lactate reference interval was established from 34 healthy dogs and was 0.7–1.4 mM, 0.3–6.0 mM, and 1.0–7.0 mM for D-, L-, and total lactate, respectively. The assay to measure D-, L-, and total lactate in canine fecal samples was linear, accurate, precise, and reproducible. Significant increases in fecal lactate and decreases in secondary BA concentrations were observed in dogs with CE and dogs with EPI. Dogs with EPI had an increased abundance of Escherichia coli, Lactobacillus, and Bifidobacterium; a decreased abundance of Fusobacterium and Clostridium hiranonis; and a higher Dysbiosis Index when compared to healthy dogs. Further studies are necessary to determine the clinical utility of lactate and BA quantification in canine feces. These metabolites suggest functional alterations of intestinal dysbiosis and may become promising targets for further elucidating the role of the microbiota in health and disease.

Effects of three major protein sources on performance, gut morphology and fermentation characteristics in broilers

1. This study determined the effects of three protein sources (PS), each at two digestibility crude protein (DCP) levels, on performance, gut morphology and fermentation characteristics in the hindgut of broilers.2. It was hypothesised that broilers fed ingredients high in indigestible CP, i.e. rapeseed meal (RSM) or maize gluten (MG), could potentially cause reduced growth, impaired gut health, and more protein fermentation products in caecal digesta. Increasing the DCP level in each of the indigestible CP diets may compensate for these detrimental effects.3. In total, 288 one-d-old male Ross 308 broilers were used in a completely randomised 3 × 2 factorial design, with six replicate pens per treatment. Three PS: soybean meal (SBM), rapeseed meal (RSM) or maize gluten (MG), and two DCP levels: 15.8 and 17.2% were used.4. Broilers fed SBM had increased feed intake and BWG and improved FCR compared with those fed RSM and MG diets. Broilers fed high DCP had better performance compared with those on low DCP. No significant effects of PS or DCP level were found on gastrointestinal tract development, caecal ammonia or volatile fatty acid concentrations.5. Broilers fed SBM had longer villi, smaller crypts and increased villus height to crypt depth ratio compared with those fed RSM and MG diets. Broilers fed RSM diet had a lower caecal pH, and had 16.5% and 14.9% more branched chain fatty acid contents in caecal digesta compared with those fed SBM and MG diets, respectively, indicating more proteolytic fermentation.6. Replacing SBM by RSM and MG negatively affected growth performance and gut morphology. Hindgut protein fermentation was substantially increased in RSM fed birds.7. To a certain extent, retarded growth performance in RSM and MG fed birds could be counterbalanced by increasing the dietary level of digestible CP.

Efficacy of an orally administered anti-diarrheal probiotic paste (Pro-Kolin Advanced) in dogs with acute diarrhea: A randomized, placebo-controlled, double-blinded clinical study

BACKGROUND

Acute diarrhea is a common clinical presentation of dogs. The effect of specific anti-diarrheal probiotic pastes (ADPPs) in the management of acute, uncomplicated diarrhea in dogs is unknown.

HYPOTHESIS

Administration of an ADPP containing Enterococcus faecium 4b1707 will improve the clinical outcome of acute, uncomplicated diarrhea in dogs compared to placebo.

ANIMALS

One hundred forty-eight client-owned dogs with acute diarrhea as the main clinical sign.

METHODS

Double-blinded, placebo-controlled, randomized, blocked, multicenter clinical field study conducted at 14 primary care veterinary practices in the United Kingdom and Ireland.

RESULTS

The ADPP was associated with better clinical outcome compared to placebo in dogs with acute, uncomplicated diarrhea. Dogs in the ADPP group had a significantly shorter duration of diarrhea (ADPP: median, 32 hours; 95% confidence interval [CI], 2-118; n = 51; Placebo: median, 47 hours; 95% CI, 4-167; n = 58; P = .008) and the rate of resolution of diarrhea was 1.60 times faster in the ADPP group than in the Placebo group (ratio, 1.60; 95% CI, 1.08-2.44; P = .02). Fewer dogs required additional medical intervention (AMI) for non-improvement or worsening in the ADPP group compared to the Placebo group (3.5% of dogs and 14.8% of dogs, respectively), with a relative risk of 0.88 (P = .04; AMI, ADPP, 3.5%, 2/57 dogs; Placebo, 14.8%, 9/61 dogs; relative risk, 0.88; 95% CI, 0.77-0.99).

CONCLUSION AND CLINICAL IMPORTANCE

The ADPP may accelerate resolution of acute diarrhea in dogs and decrease the requirement for AMI.

Effect of Calsporin® (Bacillus subtilisC-3102) addition to the diet on faecal quality and nutrient digestibility in healthy adult dogs

This study evaluated the effect ofBacillus subtilisC-3102 (Calsporin®) addition to the diet on faecal characteristics and nutrient digestibility in healthy adult dogs. Sixteen Beagles received either a low-energy control diet (CON; 3.35 Mcal metabolisable energy (ME)/kg with 21.8, 27.9, and 50.3% ME as protein, fat, and nitrogen-free extractives (NFE), respectively) or the same diet supplemented withBacillus subtilisat 1 × 109CFU/kg diet as probiotic (PRO) for four weeks in a parallel design (eight dogs per diet). In the prior two weeks, all dogs received a high-energy diet (Advance Medium Adult, Affinity Petcare®, 3.81 Mcal ME/kg ME with 24.8, 41.2, and 34% ME protein, fat, and NFE, respectively). Faecal consistency, dry matter (DM), pH, and NH3were analysed on fresh samples collected at the start and weekly throughout the study. Additional samples were collected for the determination of lactate and short-chain fatty acids (SCFA) on days 0 and 21. In week four, a five–day total faecal collection was conducted in six dogs from each diet for the determination of nutrient apparent digestibility. Dogs fed the PRO diet had more firm faeces (P = 0.011) than control dogs and a higher faecal DM content in the first two weeks (P < 0.05). Feeding the PRO diet resulted in a decline in NH3over four weeks (P = 0.05) and in faecal pH in the first two weeks (P < 0.05) alongside an increase in SCFA content (P = 0.044), mainly acetate (P = 0.024). Faecal lactate did not differ between diets (P > 0.10). Dogs fed the PRO diet showed a higher apparent digestibility of fat (P = 0.031) and NFE (P = 0.038) compared to control dogs. Dog food supplementation with Calsporin®at 1 × 109CFU/kg improved faecal quality, enhanced fat and carbohydrate digestibility, and contributed to the gut health of dogs by reducing gut ammonia and increasing SCFA content.

Apparent and true digestibility of macro and micro nutrients in adult maintenance dog foods containing either a majority of animal or vegetable proteins1

There is dearth of knowledge with regards to mineral digestibility of ingredients in canines, and current knowledge is focused on the digestibility of supplemented minerals, not on intrinsic mineral digestibility of ingredients. The objectives of the present study were to determine the apparent and true digestibility (TD) of macronutrients and micronutrients, and the total tract gastrointestinal endogenous nutrient outputs in canines fed either animal- or vegetable-based adult maintenance diets. Eight purpose bred Beagles (two intact males, six spayed females) of similar age (2.12 ± 0.35 yr, mean ± SD) and weight (9.92 ± 0.73 kg, mean ± SD) were pair housed in kennels but fed individually based on individual maintenance energy requirements. Two basal diets (animal and vegetable protein based) were formulated to meet nutritional requirements of adult canines. Two additional trial diets were created, using the basal diets, by diluting diets by 50% with anhydrous α-d-glucose to attempt to quantify endogenous mineral losses and enable calculation of TD. All diets contained titanium dioxide at 0.3% for calculations of nutrient digestibility. Dogs were provided with deionized water as their only source of water throughout the trial. Dogs in a specific kennel were randomly assigned to an experimental diet for 10 d (experimental period), and fecal samples were collected the last 4 d of each period. All dogs were fed all experimental diets in random order based on a 4 × 4 replicated Latin square design. Dogs fed intact diets had a higher apparent mineral digestibility compared to dogs fed diluted diets (P < 0.05). Apparent phosphorus digestibility was higher for dogs fed the diet 2 compared with the diet 1 (P = 0.01) and the diluted diets (P < 0.001). There was a trend towards a greater TD of Cu for dogs fed the diet 2 compared with the diet 1 (P = 0.08). P, Mg, Zn, and Mn true digestibilities were higher for dogs fed the diet 2 compared with the diet 1 (P < 0.05, P = 0.01, P = 0.02, P = 0.009, respectively). These results suggest that apparent and TD do not result in similar values. Further research should be conducted on TD in canines only if a better model is developed.

Effects of two equine digestive aid supplements on hindgut health

Gastrointestinal disease is the number one killer of horses. Little is known about the maintenance of microbes in the equine hindgut and how to distinguish a healthy gut in a live horse. Utilization of internal and external digestibility markers and starch fermentation has been extensively studied in ruminants and is the basis for research conducted on horses. The aims of this study were to investigate the effects of two equine feed digestive aid supplements on hindgut health (HGH) as reflected in fecal pH and digestibility and to compare and validate DM digestibility measurements through the use of internal and external markers such as chromium oxide (CR), lignin (Lig), indigestible ADF (iADF), indigestible NDF (iNDF), and indigestible lignin (iLig). Nine mature Quarter horses (six geldings, three mares) were used in a crossover design, three feeding periods of 17 d (51 d total), using three treatments: control, no feed additive (CON), Smartpak (SP; Plymouth, MA), or Platinum Performance (PP; Buellton, CA). Both SP and PP contained a strain of Lactobacillus, whereas SP further supplied mannanoligosaccharides (MOS) and fructooligosaccharides (FOS) and PP supplied Saccharomyces boulardii. Within the 17-d period, horses were offered orchard grass hay and sweet cob grain and the assigned treatment daily and four CR cookies to deliver 8 g/d of CR for the last 7 d of each period. Total feces were collected from 15 to 17 d. Feed and fecal samples were dried, ground, and sent to ANALAB (Fulton, IL) for nutrient analysis. Duplicate samples of feed and feces were placed in ruminally cannulated cows for in situ determination of iADF, iNDF, and iLig to estimate digestibility. Estimated CR fecal output, CR DMI, and DM digestibilities were evaluated using the root mean square prediction error percentage of the observed mean (RMSPE), concordance correlation coefficient (CCC), and Nash–Sutcliffe efficiency methods. Marker predictive ability tests showed iADF to have the least amount of bias with the smallest RMSPE (4%), largest CCC (0.43), and the largest amount of random bias (error of dispersion = 0.45). Supplementation of PP decreased CR DM digestibility (P < 0.02). Smartpak increased fecal pH (P < 0.09), but PP had no effect on fecal pH. Therefore, SP had a beneficial effect on HGH that is believed to be due to MOS and FOS.

Oat beta-glucan as a dietary supplement for dogs

The aim of this study was to evaluate the effects of oat beta-glucan supplementation on metabolic, physiological, immunological and nutritional variables in adult dogs. Fourteen dogs were fed a control diet or a diet supplemented with 1% beta-glucan during 71 days. Serum concentrations of glucose, total cholesterol and lipoprotein fractions, as well as plasma concentrations of peptide YY and ghrelin, were determined. In addition, coefficient of total tract apparent macronutrient digestibility (CTTAD), food intake and fecal output, score, and pH were evaluated. For evaluation of immunological variables, serum concentrations of interleukin-4 and interferon gamma were determined on days 0, 57 and 71, which corresponded to blood collection prior to beta-glucan supplementation, and at 7 and 14 days post first and second dose of vaccination (Pneumodog^®, Merial, Campinas, Brazil), respectively. Animals fed the supplemented diet showed (P<0.05) lower serum concentrations of total cholesterol and low and very low density lipoproteins, lower coefficients of total tract apparent digestibility of dry matter, organic matter, mineral matter and ether extract, higher fecal output and lower fecal consistency, as well as a tendency (P = 0.07) of decreasing the coefficient of total tract apparent digestibility of crude protein. Moreover, the supplemented diet resulted in lower number of red blood cells, hematocrit percentage and hemoglobin concentration 21 days post-vaccination as well as lower serum concentration of interleukin-4 seven days post-vaccination (P<0.05). It is concluded that oat beta-glucan extract can be used as a dietary supplement for dogs at a dose of 10 g/kg of food, being effective in reducing blood concentrations of total cholesterol, LDL-c and VLDL-c as well as CTTAD of nutrients, demonstrating a potential to be used in the feeding of obese animals. In addition, by reducing the predominance of a Th2 response, oat beta-glucan can positively modulate the vaccine response of animals.

Pasture flock chicken cecal microbiome responses to prebiotics and plum fiber feed amendments

When prebiotics and other fermentation substrates are delivered to animals as feed supplements, the typical goal is to improve weight gain and feed conversion. In this work, we examined pasture flock chicken cecal contents using next generation sequencing (NGS) to identify and understand the composition of the microbiome when prebiotics and fermentation substrates were supplemented. We generated 16S rRNA sequencing data for 120 separate cecal samples from groups of chickens receiving one of 3 prebiotics or fiber feed additives. The data indicated that respective feed additives enrich for specific bacterial community members and modulate the diversity of the microbiome. We applied synthetic learning in microbial ecology (SLiME) analysis to interpret 16S rRNA microbial community data and identify specific bacterial operational taxonomic units (OTU) that are predictive of the particular feed additives used in these experiments. The results suggest that feed can influence microbiome composition in a predictable way, and thus diet may have indirect effects on weight gain and feed conversion through the microbiome.

Effects of dietary yeast cell wall on faecal bacteria and fermentation products in adult cats

This study evaluated the effects of increasing concentrations of spray-dried yeast cell wall (YCW) in diets for healthy adult cats on apparent nutrient digestibility and on bacterial composition and fermentation products in the stool. Fourteen cats with an average weight of 4.40 ± 1.05 kg and an average age of 6.2 ± 0.54 years were used and assigned to treatments in an unbalanced randomized block design (by experimental period) with two blocks and three or four cats per diet in each block. Treatments included: control (0% YCW), 0.2% YCW, 0.4% YCW and 0.6% YCW, totalling seven animals per experimental diet. We found that YCW did not affect body weight, nutrient and food intake, faecal production, faecal score, faecal pH or urine output (p > .05). Regarding faecal bacteria, we observed a linear reduction in Clostridium perfringens, a quadratic reduction in Escherichia coli, and linear increases in Bifidobacterium spp. and Lactobacillus spp. (p < .05) with the inclusion of YCW. Regarding the faecal short-chain fatty acid profile, butyrate, valerate, total biogenic amines, putrescine, cadaverine and histamine increased linearly (p < .05) with the inclusion of YCW. It was concluded that in healthy adult cats, consumption of YCW modulates the faecal bacterial populations, with an increased presence of beneficial bacteria and a reduction in some potentially pathogenic bacteria. It was concluded that YCW modulated the levels of fermentation products. There was an increase in fermentation products coming from carbohydrate metabolism, an important effect that can potentially benefit the intestinal health of cats. The consumption of YCW also increased the fermentation of nitrogen compounds, which have not yet been defined as deleterious or beneficial. The fermentability of carbohydrates and nitrogen compounds may be associated. Therefore, YCW may cause rapid fermentation of both classes of compounds by enhancing the fermentability of one class.

When the Nose Doesn't Know: Canine Olfactory Function Associated With Health, Management, and Potential Links to Microbiota

The impact of health, management, and microbiota on olfactory function in canines has not been examined in review. The most important characteristic of the detection canine is its sense of smell. Olfactory receptors are primarily located on the ethmoturbinates of the nasal cavity. The vomeronasal organ is an additional site of odor detection that detects chemical signals that stimulate behavioral and/or physiological changes. Recent advances in the genetics of olfaction suggest that genetic changes, along with the unique anatomy and airflow of the canine nose, are responsible for the macrosmia of the species. Inflammation, alterations in blood flow and hydration, and systemic diseases alter olfaction and may impact working efficiency of detection canines. The scientific literature contains abundant information on the potential impact of pharmaceuticals on olfaction in humans, but only steroids, antibiotics, and anesthetic agents have been studied in the canine. Physical stressors including exercise, lack of conditioning, and high ambient temperature impact olfaction directly or indirectly in the canine. Dietary fat content, amount of food per meal, and timing of meals have been demonstrated to impact olfaction in mice and dogs. Gastrointestinal (GI) microbiota likely impacts olfaction via bidirectional communication between the GI tract and brain, and the microbiota is impacted by exercise, diet, and stress. The objective of this literature review is to discuss the specific effects of health, management, and microbiota shifts on olfactory performance in working canines.

Influence of dietary protein and fructooligosaccharides on fecal fermentative end-products, fecal bacterial populations and apparent total tract digestibility in dogs

Background

Feeding dogs with diets rich in protein may favor putrefactive fermentations in the hindgut, negatively affecting the animal’s intestinal environment. Conversely, prebiotics may improve the activity of health-promoting bacteria and prevent bacterial proteolysis in the colon. The aim of this study was to evaluate the effects of dietary supplementation with fructooligosaccharides (FOS) on fecal microbiota and apparent total tract digestibility (ATTD) in dogs fed kibbles differing in protein content. Twelve healthy adult dogs were used in a 4 × 4 replicated Latin Square design to determine the effects of four diets: 1) Low protein diet (LP, crude protein (CP) 229 g/kg dry matter (DM)); 2) High protein diet (HP, CP 304 g/kg DM); 3) Diet 1 + 1.5 g of FOS/kg; 4) Diet 2 + 1.5 g of FOS/kg. The diets contained silica at 5 g/kg as a digestion marker. Differences in protein content were obtained using different amounts of a highly digestible swine greaves meal. Each feeding period lasted 28 d, with a 12 d wash-out in between periods. Fecal samples were collected from dogs at 0, 21 and 28 d of each feeding period. Feces excreted during the last five days of each feeding period were collected and pooled in order to evaluate ATTD.

Results

Higher fecal ammonia concentrations were observed both when dogs received the HP diets (p < 0.001) and the supplementation with FOS (p < 0.05). The diets containing FOS resulted in greater ATTD of DM, Ca, Mg, Na, Zn, and Fe (p < 0.05) while HP diets were characterized by lower crude ash ATTD (p < 0.05). Significant interactions were observed between FOS and protein concentration in regards to fecal pH (p < 0.05), propionic acid (p < 0.05), acetic to propionic acid and acetic + n-butyric to propionic acid ratios (p < 0.01), bifidobacteria (p < 0.05) and ATTD of CP (p < 0.05) and Mn (p < 0.001).

Conclusions

A relatively moderate increase of dietary protein resulted in higher concentrations of ammonia in canine feces. Fructooligosaccharides displayed beneficial counteracting effects (such as increased bifidobacteria) when supplemented in HP diets, compared to those observed in LP diets and, in general, improved the ATTD of several minerals.

Non-digestible carbohydrates in infant formula as substitution for human milk oligosaccharide functions: Effects on microbiota and gut maturation

Human milk (HM) is the golden standard for nutrition of newborn infants. Human milk oligosaccharides (HMOs) are abundantly present in HM and exert multiple beneficial functions, such as support of colonization of the gut microbiota, reduction of pathogenic infections and support of immune development. HMO-composition is during lactation continuously adapted by the mother to accommodate the needs of the neonate. Unfortunately, for many valid reasons not all neonates can be fed with HM and are either totally or partly fed with cow-milk derived infant formulas, which do not contain HMOs. These cow-milk formulas are supplemented with non-digestible carbohydrates (NDCs) that have functional effects similar to that of some HMOs, since production of synthetic HMOs is challenging and still very expensive. However, NDCs cannot substitute all HMO functions. More efficacious NDCs may be developed and customized for specific groups of neonates such as pre-matures and allergy prone infants. Here current knowledge of HMO functions in the neonate in view of possible replacement of HMOs by NDCs in infant formulas is reviewed. Furthermore, methods to expedite identification of suitable NDCs and structure/function relationships are reviewed as in vivo studies in babies are impossible.

An in vitro evaluation of the effects of a Yucca schidigera extract and chestnut tannins on composition and metabolic profiles of canine and feline faecal microbiota

The in vitro effect of a Yucca schidigera extract (YSE) and tannins from chestnut wood on composition and metabolic activity of canine and feline faecal microbiota was evaluated. Four treatments were carried out: control diet, chestnut tannins (CT), YSE and CT + YSE. The YSE was added to canine and feline faecal cultures at 0.1 g/l, while CT were added at 0.3 g/l for a 24-h incubation. A total of 130 volatile compounds were detected by means of headspace-solid phase microextraction gas-chromatography/mass spectrometry analyses. Several changes in the metabolite profiles of fermentation fluids were found, including a decrease of alcohols (-19%) and esters (-42%) in feline and canine inoculum, respectively, which was due to the antibacterial properties of tannins. In canine inoculum, after 6 h, YSE + CT caused lower cadaverine concentrations (-37%), while ammonia (-4%) and quinolone (-27%) were reduced by addition of CT. After 24 h, the presence of CT resulted in a decrease of sulphur compounds, such as dimethyl sulphide (-69%) and dimethyl disulphide (-20%). In feline faecal cultures, after 6 h, CT lowered the amount of indole (-48%), whereas YSE tended to decrease trimethylamine levels (-16%). Both in canine and feline inoculum, addition of CT and, to a minor extent, YSE affected volatile fatty acids patterns. In canine faecal cultures, CT exerted a marginal inhibitory effect on Escherichia coli population (-0.45 log 10 numbers of DNA copies/ml), while enterococci were increased (+2.06 log 10 numbers of DNA copies/ml) by YSE. The results from the present study show that YSE and tannins from chestnut wood exert different effects on the composition and metabolism of canine and feline faecal microbiota. In particular, the supplementation of YSE and tannins to diets for dogs and cats may be beneficial due to the reduction of the presence of some potentially toxic volatile metabolites in the animals' intestine.

Characterization of the fecal microbiome during neonatal and early pediatric development in puppies

Limited information is available describing the development of the neonatal fecal microbiome in dogs. Feces from puppies were collected at 2, 21, 42, and 56 days after birth. Feces were also collected from the puppies’ mothers at a single time point within 24 hours after parturition. DNA was extracted from fecal samples and 454-pyrosequencing was used to profile 16S rRNA genes. Species richness continued to increase significantly from 2 days of age until 42 days of age in puppies. Furthermore, microbial communities clustered separately from each other at 2, 21, and 42 days of age. The microbial communities belonging to dams clustered separately from that of puppies at any given time point. Major phylogenetic changes were noted at all taxonomic levels with the most profound changes being a shift from primarily Firmicutes in puppies at 2 days of age to a co-dominance of Bacteroidetes, Fusobacteria, and Firmicutes by 21 days of age. Further studies are needed to elucidate the relationship between puppy microbiota development, physiological growth, neonatal survival, and morbidity.

Infant food applications of complex carbohydrates: Structure, synthesis, and function

Professional health bodies such as the World Health Organization (WHO), the American Academy of Pediatrics (AAP), and the U.S. Department of Health and Human Services (HHS) recommend breast milk as the sole source of food during the first year of life. This position recognizes human milk as being uniquely suited for infant nutrition. Nonetheless, most neonates in the West are fed alternatives by 6 months of age. Although inferior to human milk in most aspects, infant formulas are able to promote effective growth and development. However, while breast-fed infants feature a microbiota dominated by bifidobacteria, the bacterial flora of formula-fed infants is usually heterogeneous with comparatively lower levels of bifidobacteria. Thus, the objective of any infant food manufacturer is to prepare a product that results in a formula-fed infant developing a breast-fed infant-like microbiota. The goal of this focused review is to discuss the structure, synthesis, and function of carbohydrate additives that play a role in governing the composition of the infant microbiome and have other health benefits.

Fructo-oligosaccharides: Production, Purification and Potential Applications

The nutritional and therapeutic benefits of prebiotics have attracted the keen interest of consumers and food processing industry for their use as food ingredients. Fructo-oligosaccharides (FOS), new alternative sweeteners, constitute 1-kestose, nystose, and 1-beta-fructofuranosyl nystose produced from sucrose by the action of fructosyltransferase from plants, bacteria, yeast, and fungi. FOS has low caloric values, non-cariogenic properties, and help gut absorption of ions, decrease levels of lipids and cholesterol and bifidus-stimulating functionality. The purified linear fructose oligomers are added to various food products like cookies, yoghurt, infant milk products, desserts, and beverages due to their potential health benefits. This review is focused on the various aspects of biotechnological production, purification and potential applications of fructo-oligosaccharides.

Biomarkers for nutrient intake with focus on alternative sampling techniques

Biomarkers of nutrient intake or nutrient status are important objective measures of foods/nutrients as one of the most important environmental factors people are exposed to. It is very difficult to obtain accurate data on individual food intake, and there is a large variation of nutrient composition of foods consumed in a population. Thus, it is difficult to obtain precise measures of exposure to different nutrients and thereby be able to understand the relationship between diet, health, and disease. This is the background for investing considerable resources in studying biomarkers of nutrients believed to be important in our foods. Modern technology with high sensitivity and specificity concerning many nutrient biomarkers has allowed an interesting development with analyses of very small amounts of blood or tissue material. In combination with non-professional collection of blood by finger-pricking and collection on filters or sticks, this may make collection of samples and analyses of biomarkers much more available for scientists as well as health professionals and even lay people in particular in relation to the marked trend of self-monitoring of body functions linked to mobile phone technology. Assuming standard operating procedures are used for collection, drying, transport, extraction, and analysis of samples, it turns out that many analytes of nutritional interest can be measured like metabolites, drugs, lipids, vitamins, minerals, and many types of peptides and proteins. The advantage of this alternative sampling technology is that non-professionals can collect, dry, and mail the samples; the samples can often be stored under room temperature in a dry atmosphere, requiring small amounts of blood. Another promising area is the potential relation between the microbiome and biomarkers that may be measured in feces as well as in blood.