Fecal Microbiome In Dogs Research Articles

Fecal microbiome in dogs with lymphoid and nonlymphoid tumors.

The association of gut microbiota with cancer etiology and prognosis has been demonstrated in humans and rodents but has not been studied in dogs with different types of tumors. To analyze microbiome composition according to tumor progression based on metastasis, recurrence, and therapeutic response in canine tumors. Thirty-two client-owned dogs were divided into 3 groups: healthy (n=9), with lymphoma (n=12), with nonlymphoid tumors (n=11). Retrospective case series included animals were divided into subgroups according to the nature and severity of their tumors. Feces were screened for the 16S rRNA gene. Overall, alpha diversity was significantly reduced in dogs with tumors (n=23; 12 lymphoid and 11 nonlymphoid) compared to healthy dogs (n=9). Bacteroides had lower abundance in canine tumors at genus level. Staphylococcus showed significantly reduced abundance in dogs with aggressive tumor progression. Higher white blood cell (WBC) and neutrophil counts and lower hematocrit were significant in dogs with aggressive tumor. Spearman's rank correlation coefficient analysis revealed several measurements that showed moderate to strong correlations, including Coprococcus with total WBC count, neutrophil count, and hematocrit in the aggressive tumor group, and Saccharimonas with serum albumin and sodium concentration in all tumor dogs. The diversity of the gut microbiome was significantly reduced in dogs with tumors compared to healthy dogs. Correlations were found between changes in blood measurements and changes in microbiome composition in relation to paraneoplastic syndrome.

The effect of phenobarbital treatment on behavioral comorbidities and on the composition and function of the fecal microbiome in dogs with idiopathic epilepsy.

Phenobarbital (PB) is one of the most important antiseizure drugs (ASDs) to treat canine idiopathic epilepsy (IE). The effect of PB on the taxonomic changes in gastrointestinal microbiota (GIM) and their functions is less known, which may explain parts of its pharmacokinetic and pharmacodynamic properties, especially its antiseizure effect and drug responsiveness or drug resistance as well as its effect on behavioral comorbidities. Fecal samples of 12 dogs with IE were collected prior to the initiation of PB treatment and 90 days after oral PB treatment. The fecal samples were analyzed using shallow DNA shotgun sequencing, real-time polymerase chain reaction (qPCR)-based dysbiosis index (DI), and quantification of short-chain fatty acids (SCFAs). Behavioral comorbidities were evaluated using standardized online questionnaires, namely, a canine behavioral assessment and research questionnaire (cBARQ), canine cognitive dysfunction rating scale (CCDR), and an attention deficit hyperactivity disorder (ADHD) questionnaire. The results revealed no significant changes in alpha and beta diversity or in the DI, whereas only the abundance of Clostridiales was significantly decreased after PB treatment. Fecal SCFA measurement showed a significant increase in total fecal SCFA concentration and the concentrations of propionate and butyrate, while acetate concentrations revealed an upward trend after 90 days of treatment. In addition, the PB-Responder (PB-R) group had significantly higher butyrate levels compared to the PB-Non-Responder (PB-NR) group. Metagenomics of functional pathway genes demonstrated a significant increase in genes in trehalose biosynthesis, ribosomal synthesis, and gluconeogenesis, but a decrease in V-ATPase-related oxidative phosphorylation. For behavioral assessment, cBARQ analysis showed improvement in stranger-directed fear, non-social fear, and trainability, while there were no differences in ADHD-like behavior and canine cognitive dysfunction (CCD) scores after 90 days of PB treatment. While only very minor shifts in bacterial taxonomy were detected, the higher SCFA concentrations after PB treatment could be one of the key differences between PB-R and PB-NR. These results suggest functional changes in GIM in canine IE treatment.

Characterization of the Fecal Microbiome in Dogs Receiving Medical Management for Congenital Portosystemic Shunts.

BackgroundThe GI microbiome has not been characterized in dogs being medically managed for congenital portosystemic shunts (CPSS).ObjectivesTo characterize the fecal microbiome in a population of dogs being medically managed for CPSS.Animals27 client-owned dogs.MethodsProspective cohort study enrollment of fecal samples was performed with follow-up data collected retrospectively. The overall fecal dysbiosis index (DI) and individual bacterial abundances were determined using real-time qPCR. Medical management, clinical findings, clinicopathologic, and outcome variables were collected, and logistic regression analyses were performed to evaluate associations between these variables and overall DI and bacterial abundances. Numerical variables were evaluated with general linear models for normality and equal variance using Shapiro-Wilk test and Levene's test, respectively.ResultsAll dogs were administered a hepatic diet and lactulose, while antibiotics were used in 22 (81.5%) and acid suppressants in 7 (25.9%). Seventeen dogs (63.0%) had a DI >2. The median DI in this population was 3.02 (range 4.23–8.42), and the median DI in dogs receiving and not receiving antibiotics was 4.3 (range −4.23–8.42) and 1.52 (range −1.62–5.43), respectively. No significant association between any of the analyzed variables and the DI was identified. There was a significant association between the use of metronidazole and a larger abundance of E. coli (p = 0.024).Conclusions and Clinical ImportanceDysbiosis appears to be common in dogs that are being medically managed for CPSS, though the clinical significance remains unclear.

Comparison of the Therapeutic Effect of Treatment with Antibiotics or Nutraceuticals on Clinical Activity and the Fecal Microbiome of Dogs with Acute Diarrhea.

Simple SummaryAcute diarrhea in dogs is one of the most common reasons for veterinary visits. Although this disorder is generally self-limiting, antibiotics are still frequently used as treatment for acute diarrhea in clinical practice. Antimicrobial resistance represents a major challenge for public health and requires immediate and drastic solutions. To date, the emergence and spread of antimicrobial resistance has been attributed to the misuse or indiscriminate use of antibiotics. The aim of this study is to compare the effects on clinical activity and fecal microbiota of the administration of an antibiotic combination in comparison to a nutraceutical product in dogs with acute non-hemorrhagic diarrhea. The results of the present study suggest that this nutraceutical treatment had a similar clinical effect compared to the antibiotic formulation and may represent an alternative to commonly used antimicrobial therapy.Dogs with acute diarrhea are often presented to clinical practice and, although this generally represents a self-limiting condition, antibiotics are still frequently used as treatment. The aim of this study was to evaluate the effects in dogs with acute non-hemorrhagic diarrhea of the administration of an antibiotic combination in comparison to a nutraceutical product. Thirty dogs were enrolled and randomly assigned to two groups: 15 dogs (group A) received a nutraceutical commercial product while 15 dogs (group B) received an antimicrobial combination of metronidazole and spiramycin. For each dog, the Canine Acute Diarrhea Severity Index, the fecal microbiota and the Dysbiosis Index were assessed. Both stool consistency and frequency decreased on day 2 in the dogs of group A compared to baseline, while in group B, these parameters significantly decreased at days 3 and 4. The global concern for rising antibiotic resistance associated with indiscriminate use of antimicrobials, in both humans and animals, suggests the necessity of avoiding empirical and injudicious use of these molecules in diarrheic dogs. These results suggest that the nutraceutical treatment had a similar clinical effect compared to the antibiotic formulation, representing a valid antibiotic-sparing therapeutic approach in canine acute diarrhea.

Effect of a novel nutraceutical supplement (Relaxigen Pet dog) on the fecal microbiome and stress-related behaviors in dogs: A pilot study

Anxiety and stress can trigger functional gastrointestinal disorders, whereas gastrointestinal symptoms can significantly increase anxiety and depression levels. These patterns are associated with the connection of the intestine and the brain through the “gut-brain axis,” a bi-directional communication of the nervous, endocrine, and immune systems. This clinical trial sought to investigate the effects of a novel nutraceutical supplement (Relaxigen Pet dog) containing natural anti-inflammatory compounds (CLA, Krill), pre/probiotics, 5-HTP, and L-theanine on stress-related behavior and to assess the connection between these stress-related behaviors and the fecal microbiome in dogs. Forty dogs, ranging in ages from 1 to 10 years, took part in this double-blind, placebo-controlled clinical trial. Ten dogs were control dogs without overt clinical signs of anxiety. Thirty dogs (experimental dogs) with signs of stress and anxiety were randomly assigned to the treatment (N = 20) and placebo (N = 10) groups. The treatment sample group (20 dogs balanced for sex) was administered with Relaxigen Pet dog tablets and the placebo group (10 dogs balanced for sex) with placebo tablets by mouth once a day for 60 days. A basic history questionnaire that focused on all aspects of dog's behavior, management, health issues, and behavioral signs of stress and anxiety, was collected at days 0, 30, and 60 for each experimental dog. A fecal sample was collected for all dogs at day 0 to compare the microbiome of the anxious and non-anxious dogs. The anxious dogs in the treatment and placebo dogs groups had a fecal sample collected again at 30 and 60 days. These samples were used to extract the DNA for microbiological analysis and to determine the leading bacterial group. ANOVA showed an influence of treatment × time and the group that received the treatment had a probability of improving greater than 10% (P ≤ 0.05). This study revealed a different structure of the intestinal microbiota between healthy dogs and those with stress-related behaviors at baseline. Supplementation with the Relaxigen seems to bring some changes in bacterial groups concentration in the treatment group of anxious dogs compared to the placebo one, but we must be very cautious in presenting these results due to the limitations of this pilot study (number of subjects, no dietary control, and no evaluation of microbiota over time for the control group dogs).

Effect of Added Dietary Betaine and Soluble Fiber on Metabolites and Fecal Microbiome in Dogs with Early Renal Disease.

Renal diets are recommended for dogs with chronic kidney disease (CKD). This study examined the effects of foods with added betaine and fiber on the plasma and fecal metabolome and fecal microbiome in dogs with early stage CKD. At baseline, several metabolites differed between healthy dogs and those with CKD. Dogs with CKD (n = 28) received a control food, low soluble fiber plus betaine food (0.5% betaine, 0.39% oat beta-glucan, and 0.27% short-chain fructooligosaccharides (scFOS)), or high soluble fiber plus betaine food (0.5% betaine, 0.59% oat beta-glucan, and 0.41% scFOS) each for 10 weeks in different sequences. Consumption of test foods led to several favorable, significant changes in the plasma metabolome, including decreases of several uremic toxins and other deleterious metabolites, and increases in favorable metabolites compared with the control food. Only 7 fecal metabolites significantly changed with consumption of the test foods compared with the control food, largely increases in polyphenols and lignans. Few changes were seen in the fecal microbiome, though some taxa that significantly changed in response to the test foods have beneficial effects on health, with some negatively correlating with uremic toxins. Overall, foods with added betaine and soluble fiber showed positive effects on the plasma and fecal metabolomes.

An ambient temperature collection and stabilization strategy for canine microbiota studies

Similar to humans, the fecal microbiome of dogs may be useful in diagnosing diseases or assessing dietary interventions. The accuracy and reproducibility of microbiome data depend on sample integrity, which can be affected by storage methods. Here, we evaluated the ability of a stabilization device to preserve canine fecal samples under various storage conditions simulating shipping in hot or cold climates. Microbiota data from unstabilized samples stored at room temperature (RT) and samples placed in PERFORMAbiome·GUT collection devices (PB-200) (DNA Genotek, Inc. Ottawa, Canada) and stored at RT, 37 °C, 50 °C, or undergoing repeated freeze–thaw cycles, were compared with freshly extracted samples. Alpha- and beta diversity indices were not affected in stabilized samples, regardless of storage temperature. Unstabilized samples stored at RT, however, had higher alpha diversity. Moreover, the relative abundance of dominant bacterial phyla (Firmicutes, Fusobacteria, Bacteriodetes, and Actinobacteria) and 24 genera were altered in unstabilized samples stored at RT, while microbiota abundance was not significantly changed in stabilized samples stored at RT. Our results suggest that storage method is important in microbiota studies and that the stabilization device may be useful in maintaining microbial profile integrity, especially for samples collected off-site and/or those undergoing temperature changes during shipment or storage.

Effect of different starch sources in a raw meat-based diet on fecal microbiome in dogs housed in a shelter.

A dietary intervention study was assessed to determine if different sources of starch in homemade diets could significantly modify fecal microbiome of dogs. Twenty-seven adult dogs were enrolled and fed a diet based on a mixture of rice and pasta with fresh raw meat (CD). After 90 d, 8 dogs continued to receive CD diet, 10 dogs received a diet made of a raw meat and a complementary food with rice as the main source of starch (B1), and 9 dogs were fed a diet with the same raw meat and a complementary food with potato as the main source of starch (B2). Samples of feces were collected from each dog in the mornings at the beginning of the study and after 15 d and analyzed for pH, ammonia N (N–NH3) and total N, short chain fatty acids (SCFA) and lactic acid. Relative abundance of fecal microbiota was assessed by sequencing and annotating the V3–V4 regions of the 16S rRNA. Total starch intake was similar between diets but differed in the in vitro rate digestion and in the resistant starch, which was higher in B2 than in B1 and CD diets. Dogs fed B2 diet showed lower (P < 0.05) N–NH3 and pH but higher (P < 0.05) molar proportion of lactic acid. Linear discriminant analysis of the genera relative abundances indicated a significant (P < 0.01) increase of SMB53 genus at the end of the study in B1 diet and of Megamonas genus in B1 and B2 diets in comparison to CD diet. These results suggest that changes of starch source in a raw meat-based diet have limited effects on fecal microbiome in healthy dogs, but underline a high variability of microbiota among dogs.

Evaluation of the effects of anthelmintic administration on the fecal microbiome of healthy dogs with and without subclinical Giardiaspp. and Cryptosporidium canisinfections.

BackgroundThe gastrointestinal microbiome plays an important role in host health and there is increasing concern regarding the deleterious effects of pharmaceuticals on the fecal microbiome. The effect of anthelmintic therapy on the fecal microbiome in dogs has not yet been evaluated. The purpose of this study was to evaluate the effect of anthelmintic administration on the fecal microbiome of dogs with and without subclinical Giardia species and Cryptosporidium canis infections.Methodology/Principal findingsPart 1: 6 healthy adult research beagles with subclinical giardiasis and cryptosporidiosis were administered a commercially available preparation of febantel combined with pyrantel and praziquantel (FPP) orally daily for three days. Part 2: 19 healthy staff-owned dogs without giardiasis or cryptosporidiosis were divided into a treatment group (n = 9) that was administered fenbendazole orally daily for five days and an untreated control group (n = 10). For both parts of the study, feces were collected at multiple time points before and after anthelmintic (FPP or fenbendazole) administration. Fecal DNA was extracted for Illumina sequencing of the bacterial 16S rRNA gene and qPCR assays. Neither FPP nor fenbendazole treatment caused a significant change in alpha or beta diversity or the relative abundance of bacterial species. Upon univariate statistical analysis neither FPP or fenbendazole caused minimal changes in the fecal microbiota.ConclusionFPP administration was associated with minimal alterations of the fecal microbiome of healthy research beagles with subclinical giardiasis and cryptosporidiosis. Fenbendazole administration was associated with minimal alterations of the fecal microbiome of healthy staff owned dogs.

Impact of Breed on the Fecal Microbiome of Dogs under the Same Dietary Condition.

The gut microbiome influences the health and well-being of dogs. However, little is known about the impact of breed on the fecal microbiome composition in dogs. Therefore, we aimed to investigate the differences in the fecal microbiome in three breeds of dog fed and housed under the same conditions, namely eight Maltese (8.0 ± 0.1 years), eight Miniature Schnauzer (8.0 ± 0.0 years), and nine Poodle dogs (8.0 ± 0.0 years). Fresh fecal samples were collected from the dogs and used to extract metagenomic DNA. The composition of the fecal microbiome was evaluated by 16S rRNA gene amplicon sequencing on the MiSeq platform. A total of 840,501 sequences were obtained from the 25 fecal samples and classified as Firmicutes (32.3-97.3% of the total sequences), Bacteroidetes (0.1-62.6%), Actinobacteria (0.2-14.7%), Fusobacteria (0.0-5.7%), and Proteobacteria (0.0-5.1%). The relative abundance of Firmicutes was significantly lower in the Maltese dog breed than that in the other two breeds, while that of Fusobacteria was significantly higher in the Maltese than in the Miniature Schnauzer breed. At the genus level, the relative abundance of Streptococcus, Fusobacterium, Turicibacter, Succinivibrio, and Anaerobiospirillum differed significantly among the three dog breeds. These genera had no correlation with age, diet, sex, body weight, vaccination history, or parasite protection history. Within a breed, some of these genera had a correlation with at least one blood chemistry value. This study indicates that the composition of the fecal microbiome in dogs is affected by breed.

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.

The Fecal Microbiome in Dogs with Acute Diarrhea and Idiopathic Inflammatory Bowel Disease

BackgroundRecent molecular studies have revealed a highly complex bacterial assembly in the canine intestinal tract. There is mounting evidence that microbes play an important role in the pathogenesis of acute and chronic enteropathies of dogs, including idiopathic inflammatory bowel disease (IBD). The aim of this study was to characterize the bacterial microbiota in dogs with various gastrointestinal disorders.Methodology/Principal FindingsFecal samples from healthy dogs (n = 32), dogs with acute non-hemorrhagic diarrhea (NHD; n = 12), dogs with acute hemorrhagic diarrhea (AHD; n = 13), and dogs with active (n = 9) and therapeutically controlled idiopathic IBD (n = 10) were analyzed by 454-pyrosequencing of the 16S rRNA gene and qPCR assays. Dogs with acute diarrhea, especially those with AHD, had the most profound alterations in their microbiome, as significant separations were observed on PCoA plots of unweighted Unifrac distances. Dogs with AHD had significant decreases in Blautia, Ruminococcaceae including Faecalibacterium, and Turicibacter spp., and significant increases in genus Sutterella and Clostridium perfringens when compared to healthy dogs. No significant separation on PCoA plots was observed for the dogs with IBD. Faecalibacterium spp. and Fusobacteria were, however, decreased in the dogs with clinically active IBD, but increased during time periods of clinically insignificant IBD, as defined by a clinical IBD activity index (CIBDAI).ConclusionsResults of this study revealed a bacterial dysbiosis in fecal samples of dogs with various GI disorders. The observed changes in the microbiome differed between acute and chronic disease states. The bacterial groups that were commonly decreased during diarrhea are considered to be important short-chain fatty acid producers and may be important for canine intestinal health. Future studies should correlate these observed phylogenetic differences with functional changes in the intestinal microbiome of dogs with defined disease phenotypes.