Serum metabolomics of diabetic dogs treated with daily administration of a commercially available lyophilized feces preparation

Veterinary Research Communications · 2026-03-27

Enteric microbial dysbiosis can contribute to the pathobiology of canine diabetes mellitus (DM) by interfering with host metabolism, promoting inflammation, and altering incretin hormone responses. Enriching and diversifying an unbalanced gastrointestinal microbiome with microbiome-based interventions such as lyophilized fecal preparations (LFP) can help improve gut function and glycemic control of diabetic dogs. This study aimed to determine the differences in the serum metabolomes, levels of interstitial glucose (IG), and 24-hour water intake of diabetic dogs treated with daily administration of LFP or placebo. A prospective, randomized, double-masked, placebo-controlled clinical trial was conducted using six DM dogs in the LFP group and six DM dogs in the placebo group. Dogs had physical examinations and 24-hour water intake assessments at admission, 2, 4, 6, and 8 weeks, with continuous IG monitoring performed throughout the study. Serum samples were collected longitudinally at baseline and during follow-up for untargeted metabolomic analysis. The marginal mean of IG after 8 weeks was lower in the LFP group (286 ± 22 mg/dL vs. 309 ± 22 mg/dL; p = 0.468), with the LFP group showing lower marginal mean IG at each time point except week five. Marginal mean log 24-hour water intake was significantly lower in the LFP group compared to placebo (mean difference − 0.24 ± 0.10, p = 0.024). Treatment groups significantly differed in metabolites with important roles in carbohydrate, protein, and lipid metabolism. Overall, our results show that LFP induced measurable metabolic alterations, with patterns generally consistent with a more favorable metabolic profile, but only minimal improvement in glycemic control.

Exocrine Pancreatic Insufficiency in Dogs

2026-01-14

Exocrine pancreatic insufficiency (EPI) is a malabsorptive disorder caused by inadequate production of digestive enzymes from the exocrine pancreas, leading to impaired digestion and nutrient absorption. Markedly affected dogs typically present with weight loss, diarrhea, and polyphagia despite a good appetite. Because the pancreas has a large functional reserve, clinical signs only appear after significant loss of function. Diagnosis relies on recognition of compatible signs and quantification of serum trypsin-like immunoreactivity (TLI) test. Low TLI concentrations are compatible with a diagnosis of EPI. Treatment involves pancreatic enzyme replacement (PERT), often with cobalamin supplementation and dietary adjustments. With high-quality treatment and monitoring, most dogs achieve clinical remission and maintain a good quality of life.

The effect of lyophilised oral faecal microbial transplantation on functional outcomes in dogs with diabetes mellitus

Journal of Small Animal Practice · 2025-04-15 · 2 citations

OBJECTIVES: We aimed to determine if oral faecal microbiota transplantation improves indices of glycaemic control, changes the faecal dysbiosis indices, alters faecal short-chain fatty acid and bile acid profiles and increases serum glucagon-like-peptide 1 concentrations in diabetic dogs. MATERIALS AND METHODS: In this prospective randomised, placebo-controlled, double-blinded pilot study, we recruited nine diabetic dogs (five faecal microbiota transplantation and four placebo) and nine healthy controls. RESULTS: Compared to healthy dogs, diabetic dogs had altered faecal short-chain fatty acid and bile acid profiles. In the first 30 days, the faecal microbiota transplantation group had a more rapid decline in interstitial glucose; however, the mean interstitial glucose of the faecal microbiota transplantation recipients did not differ from the placebo recipients at the end of the study. Compared with placebo, faecal microbiota transplantation recipients had a decreased 24-hour water intake at day 60 and increased faecal abundance of Faecalibacterium. CLINICAL SIGNIFICANCE: This study provides a proof of concept for faecal microbiota transplantation in canine diabetes, and its data could inform the design of future large-scale studies. Further investigation is required to determine whether faecal microbiota transplantation would have any role as an adjunctive therapy in canine diabetes and to elucidate the mechanisms by which faecal microbiota transplantation may provide a beneficial clinical effect in canine diabetes.

Oral itraconazole may alter the gastrointestinal microbiome in healthy cats

American Journal of Veterinary Research · 2025-12-30

Objective: To determine if and how oral itraconazole alters the gastrointestinal microbiome of cats. Methods: This was a single-arm, longitudinal exploratory study performed in a university setting. Healthy cats were administered 5 mg/kg/day of itraconazole solution orally with food during alternating weeks over a 5-week time period. Rectal swabs were collected at 2 time points before treatment and serially during and after treatment over 31 weeks. Bacterial and fungal populations were quantified by 16S and internal transcribed spacer 3 and 4 sequencing, respectively. Changes in α diversity, β diversity, and differential abundance were evaluated over time. Results: There were no significant changes in bacterial α diversity, β diversity (R2 = 0.0077; P = .550), or relative abundance between the 2 pretreatment time points indicating stable microbial populations before itraconazole exposure in 16 cats. Time was a significant determinant of β diversity during and after itraconazole treatment (R2 = 0.0181; P = .002), and several α-diversity indices significantly decreased in the posttreatment timeframe. Ruminococcus torques (-1.916; 95% CI, -2.971 to -0.861), Acidaminococcus spp (-1.291; 95%, CI -1.866 to -0.716), and Blautia hansenii (-1.475, 95% CI, -2.295 to -0.691) relative abundances were significantly decreased at weeks 1, 5, and 9, respectively. The final fungal internal transcribed spacer dataset only included 5 taxa limiting analysis and interpretation. Conclusions: These findings provide preliminary evidence for possible dysbiosis in the feline gastrointestinal tract during itraconazole treatment. However, many changes in differential abundance were small and no longer significant posttreatment. Clinical Relevance: Itraconazole administration might induce gastrointestinal bacterial dysbiosis in cats. Alternate methods for fungal microbiome assessment should be used in future feline studies.

Untargeted metabolomics reveals the effects of pre-analytic storage on serum metabolite profiles from healthy cats

PLoS ONE · 2024-05-30 · 1 citations

Untargeted metabolomics investigations have characterized metabolic disturbances associated with various diseases in domestic cats. However, the pre-analytic stability of serum metabolites in the species is unknown. Our objective was to compare serum metabolomes from healthy cats stored at -20°C for up to 12 months to samples stored at -80°C. Serum samples from 8 adult, healthy cats were stored at -20°C for 6 months, -20°C for 12 months, or -80°C for 12 months. Untargeted liquid chromatography-mass spectrometry was used to generate serum metabolite profiles containing relative abundances of 733 serum metabolites that were compared among storage conditions. Unsupervised analysis with principal component analysis and hierarchical clustering of Euclidian distances revealed separation of samples from individual cats regardless of storage condition. Linear mixed-effects models identified 75 metabolites that differed significantly among storage conditions. Intraclass correlation analysis (ICC) classified most serum metabolites as having excellent (ICC ≥ 0.9; 33%) or moderate (ICC 0.75-0.89; 33%) stability, whereas 13% had poor stability (ICC < 0.5). Biochemicals that varied significantly among storage conditions and classified with poor stability included glutathione metabolites, amino acids, gamma-glutamyl amino acids, and polyunsaturated fatty acids. The benzoate; glycine, serine and threonine; tryptophan; chemical (xenobiotics); acetylated peptide, and primary bile acid sub pathways were enriched among highly stable metabolites, whereas the monohydroxy fatty acid, polyunsaturated fatty, and monoacylglycerol sub-pathways were enriched among unstable metabolites. Our findings suggest that serum metabolome profiles are representative of the cat of origin, regardless of storage condition. However, changes in specific serum metabolites, especially glutathione, gamma-glutamyl amino acid, and fatty acid metabolites were consistent with increased sample oxidation during storage at -20°C compared with -80°C. By investigating the pre-analytic stability of serum metabolites, this investigation provides valuable insights that could aid other investigators in planning and interpreting studies of serum metabolomes in cats.

Fecal microbiome composition and diversity of cryopreserved canine stool at different duration and storage conditions

PLoS ONE · 2024-02-07 · 8 citations

Fresh-frozen stool banks intended for humans with gastrointestinal and metabolic disorders have been recently established and there are ongoing efforts to establish the first veterinary fresh-frozen stool bank. Fresh frozen stored feces provide an advantage of increased availability and accessibility to high-quality optimal donor fecal material. The stability of frozen canine feces regarding fecal microbiome composition and diversity has not been reported in dogs, providing the basis for this study. We hypothesized that fecal microbial composition and diversity of healthy dogs would remain stable when stored at -20°C and -80°C for up to 12 months compared to baseline samples evaluated before freezing. Stool samples were collected from 20 apparently healthy dogs, manually homogenized, cryopreserved in 20% glycerol and aliquoted, frozen in liquid nitrogen and stored at -20°C or -80°C for 3, 6, 9, and 12 months. At baseline and after period of storage, aliquots were thawed and treated with propidium monoazide before fecal DNA extraction. Following long-read 16S-rRNA amplicon sequencing, bacterial community composition and diversity were compared among treatment groups. We demonstrated that fresh-frozen canine stools collected from 20 apparently healthy dogs could be stored for up to 12 months at -80°C with minimal change in microbial community composition and diversity and that storage at -80°C is superior to storage at -20°C. We also found that differences between dogs had the largest effect on community composition and diversity. Relative abundances of certain bacterial taxa, including those known to be short-chain fatty acid producers, varied significantly with specific storage temperatures and duration. Further work is required to ascertain whether fecal donor material that differs in bacterial community composition and diversity across storage conditions and duration could lead to differences in clinical efficacy for specific clinical indications of fecal microbiota transplantation.

166 Development of non-model organoids in animal research: A paradigm shift in in vitro models

Journal of Animal Science · 2024-09-01

Abstract For decades, two-dimensional (2D) cell cultures have been used as the gold standard in vitro models for basic research, drug discovery and preclinical screening applications. However, since 2009, the field has quickly shifted towards the use of three-dimensional (3D) stem cell-derived organoids. Organoids offer a variety of advantages compared with conventional 2D models, including being self-organized, retaining their cellular polarity, and being simplified versions of organs in vitro. Adult stem cells can self-renew, differentiate into multiple cell types, and are genomically stable over multiple passage lines, providing a variety of technical benefits and offering the closest recapitulation of the in vivo environment. Our laboratory has focused on expanding, characterizing, and utilizing animal-derived 3D organoid models, specifically focusing on canines; but also including other animals such as swine, turtles, snakes, and squirrels to study their unique adaptations. Practically, we can use 3D canine colonoids for the screening of anti-inflammatory candidates using our tumor necrosis factor (TNF)-α stimulation model. Additionally, we have grown and used swine lung organoids as a model for studying H1N1 viral uptake. Furthermore, we have grown and bio-banked tumor organoids/spheroids from a variety of canine cancers, including urothelial carcinoma (derived from urine and biopsies) and nasal carcinoma, among others, with future applications in precision veterinary medicine and comparative oncology. To accomplish this goal, we have carried out in vitro screening of a variety of chemotherapies and combination therapies at different concentrations across patients to predict in vivo responses and demonstrate the predictive ability of the organoid model. Finally, our laboratory has derived and characterized a variety of healthy organoid lines from canines including the pancreas, lung, liver, bladder, colon, and pituitary to act as healthy controls in mechanistic studies looking at disease pathogenesis and for uses in basic biology. In summary, in vitro organoid models from various animal species and tissues can be used in a variety of basic and applied research fields, including virology, toxicology, and oncology, with the potential to broaden our scientific understanding of disease and overall improve human and veterinary medicine.

Exocrine pancreatic insufficiency in dogs and cats

Journal of the American Veterinary Medical Association · 2023 · 20 citations

• Medicine
• Internal medicine

Exocrine pancreatic insufficiency (EPI) is a malabsorptive syndrome caused by insufficient secretion of digestive enzymes from pancreatic acini. The most common causes of EPI in dogs and cats are pancreatic acinar atrophy and chronic pancreatitis. EPI is diagnosed by measurement of species-specific immunoassays for serum trypsin-like immunoreactivity, the concentration of which directly reflects the mass of functioning pancreatic acinar tissue. EPI is treated by pancreatic enzyme replacement therapy, nutritional management (low-residue diets with moderate fat content), and supplementation of cobalamin. Some dogs and cats have persistent clinical signs despite these treatments. Growing evidence suggests that these clinical signs may be due to enteric microbiota dysbiosis or the presence of concurrent diseases such as chronic enteropathies. Management of these abnormalities may improve outcome in dogs and cats with EPI. The long-term prognosis for dogs and cats with EPI is generally good if high-quality medical therapy is provided. Future studies are needed to further understand the causes of persistent dysbiosis in animals with EPI following initiation of pancreatic enzyme replacement therapy and assess the efficacy of treatments to ameliorate these abnormalities.

Chronic Inflammatory Enteropathy and Low-Grade Intestinal T-Cell Lymphoma Are Associated with Altered Microbial Tryptophan Catabolism in Cats

Animals · 2023-12-23 · 6 citations

Chronic inflammatory enteropathy (CIE) and low-grade intestinal T-cell lymphoma (LGITL) are common chronic enteropathies (CE) in cats. Enteric microbiota dysbiosis is implicated in the pathogenesis of CE; however, the mechanisms of host–microbiome interactions are poorly understood in cats. Microbial indole catabolites of tryptophan (MICT) are gut bacterial catabolites of tryptophan that are hypothesized to regulate intestinal inflammation and mucosal barrier function. MICTs are decreased in the sera of humans with inflammatory bowel disease and previous studies identified altered tryptophan metabolism in cats with CE. We sought to determine whether MICTs were decreased in cats with CE using archived serum samples from cats with CIE (n = 44) or LGITL (n = 31) and healthy controls (n = 26). Quantitative LC-MS/MS was used to measure serum concentrations of tryptophan, its endogenous catabolites (kynurenine, kynurenate, serotonin) and MICTs (indolepyruvate, indolealdehyde, indoleacrylate, indoleacetamide, indoleacetate, indolelactate, indolepropionate, tryptamine). Serum concentrations of tryptophan, indolepropionate, indoleacrylate, indolealdehyde, indolepyruvate, indolelactate were significantly decreased in the CIE and LGITL groups compared to those in healthy controls. Indolelactate concentrations were significantly lower in cats with LGITL compared to CIE (p = 0.006). Significant correlations were detected among serum MICTs and cobalamin, folate, fPLI, and fTLI. Our findings suggest that MICTs are promising biomarkers to investigate the role of gut bacteria in the pathobiology of chronic enteropathies in cats.

P51 | Evaluation of potential anti‐inflammatory and barrier‐enhancing effects of indoles on the canine duodenum using intestinal organoids

Journal of Veterinary Pharmacology and Therapeutics · 2023-06-01

interventions to decrease the development and spread of AMR from broiler farms.