The effects of selected sedatives on basal and stimulated serum cortisol concentrations in healthy dogs.

Background: Hormone assessment is typically recommended for awake, unsedated dogs. However, one of the most commonly asked questions from veterinary practitioners to the endocrinology laboratory is how sedation impacts cortisol concentrations and the adrenocorticotropic hormone (ACTH) stimulation test. Butorphanol, dexmedetomidine, and trazodone are common sedatives for dogs, but their impact on the hypothalamic-pituitary-adrenal axis (HPA) is unknown. The objective of this study was to evaluate the effects of butorphanol, dexmedetomidine, and trazodone on serum cortisol concentrations. Methods: Twelve healthy beagles were included in a prospective, randomized, four-period crossover design study with a 7-day washout. ACTH stimulation test results were determined after saline (0.5 mL IV), butorphanol (0.3 mg/kg IV), dexmedetomidine (4 µg/kg IV), and trazodone (3-5 mg/kg PO) administration. Results: Compared to saline, butorphanol increased basal (median 11.75 µg/dL (range 2.50-23.00) (324.13 nmol/L; range 68.97-634.48) vs 1.27 µg/dL (0.74-2.10) (35.03 nmol/L; 20.41-57.93); P < 0.0001) and post-ACTH cortisol concentrations (17.05 µg/dL (12.40-26.00) (470.34 nmol/L; 342.07-717.24) vs 13.75 µg/dL (10.00-18.90) (379.31 nmol/L; 275.96-521.38); P ≤ 0.0001). Dexmedetomidine and trazodone did not significantly affect basal (1.55 µg/dL (range 0.75-1.55) (42.76 nmol/L; 20.69-42.76); P = 0.33 and 0.79 µg/dL (range 0.69-1.89) (21.79 nmol/L; 19.03-52.14); P = 0.13, respectively, vs saline 1.27 (0.74-2.10) (35.03 nmol/L; 20.41-57.93)) or post-ACTH cortisol concentrations (14.35 µg/dL (range 10.70-18.00) (395.86 nmol/L; 295.17-496.55); (P = 0.98 and 12.90 µg/dL (range 8.94-17.40) (355.86 nmol/L; 246.62-480); P = 0.65), respectively, vs saline 13.75 µg/dL (10.00-18.60) (379.31 nmol/L; 275.86-513.10). Conclusion: Butorphanol administration should be avoided prior to ACTH stimulation testing in dogs. Further evaluation of dexmedetomidine and trazodone's effects on adrenocortical hormone testing in dogs suspected of HPA derangements is warranted to confirm they do not impact clinical diagnosis.

Clinicopathologic and gastrointestinal effects of administration of prednisone, prednisone with omeprazole, or prednisone with probiotics to dogs: A double-blind randomized trial.

BACKGROUND: The efffect of administering of probiotics or twice-daily omeprazole on glucocorticoid-induced gastric bleeding in dogs is unknown. HYPOTHESIS: Compare gastrointestinal bleeding among dogs administered placebo, prednisone (2 mg/kg q24h), prednisone with omeprazole (1 mg/kg q12h), or prednisone with probiotics (Visbiome, 11.2-22.5 billion CFU/kg q24h) for 28 days. ANIMALS: Twenty-four healthy research dogs. METHODS: Double-blinded, placebo-controlled randomized trial. Clinical signs and endoscopic gastrointestinal mucosal lesion scores at baseline (t1 ), day 14 (t2 ), and day 28 (t3 ) were compared using split-plot repeated-measures mixed-model ANOVAs. RESULTS: Fecal score differed by treatment-by-time (F[6,40] = 2.65, P < .03), with higher scores in groups receiving prednisone at t3 than t1 . Nineteen of thirty-three episodes of diarrhea occurred in the prednisone with omeprazole group. Gastric mucosal lesion scores differed by treatment-by-time (F[6,60] = 2.86, P = .05), among treatment groups (F[3,60] = 4.9, P = .004), and over time (F[2,60] = 16.5, P < .001). Post hoc analysis revealed lesion scores increased over time for all groups receiving prednisone. At t3 , scores for the prednisone (8.7 ± 4.9) and prednisone with probiotics (8.7 ± 4.9) groups differed significantly from placebo (1.8 ± 1.8; P ≤ .04), whereas scores for the prednisone with omeprazole (6.5 ± 5.5) group did not differ from placebo (P = .7). Ulcers occurred only in dogs receiving prednisone. CONCLUSIONS AND CLINICAL IMPORTANCE: Prednisone-induced gastric bleeding. Co-administration of omeprazole partially mitigated bleeding, but a similar protective benefit was not demonstrated by co-administration of the evaluated probiotic.

Virtual Clinics: A Student-Led, Problem-Based Learning Approach to Supplement Veterinary Clinical Experiences.

The COVID-19 pandemic created an abrupt need for effective remote clinical experiences for senior clinical veterinary students. Subsequently, the authors created virtual clinics. This activity was derived from a problem-based learning (PBL) model wherein students designed clinical cases and participated through virtual role play as clients and clinicians. The purpose of this article is to describe virtual clinics and to report data from focus groups of participating students and faculty facilitators from two institutions regarding the positive and negative aspects of the shift in practice. A few common emerging themes included that case rounds were fun and engaging, students could learn at their own pace, and peer-to-peer learning opportunities had perceived value. Themes are reflected against the pedagogical literature to draw out areas that resonated. Students felt this activity was more engaging than listening to a discussion of a case they had no ownership of, and facilitators agreed that the peer-to-peer interactions added to student engagement. Additionally, students developed deeper knowledge about the underlying disease process and clinical presentation of their case, which required independent and self-directed learning, enabling students to think about a case from a client's perspective. By participating in these activities, students developed skills of classroom-to-clinic transitional value. While virtual clinics should not replace in-person clinical experiences, this activity might be useful to facilitate students' transition from a structured classroom setting to a less-structured clinical experience.

Proficiency and Retention of Five Clinical Veterinary Skills Using Multipurpose Reusable Canine Manikins vs. Live Animals: Model Development and Validation.

Simulation in veterinary education provides a safe and ethical alternative to using live animals, but most simulators are single purpose and unvalidated. In this study, canine training manikins were created using readily available materials to teach fine needle aspiration (FNA) of peripheral lymph nodes, jugular venipuncture, cephalic venipuncture, intravenous catheterization, and cystocentesis. Undergraduate subjects were prospectively enrolled and stratified by veterinary experience prior to randomization into two groups. Students were taught a new skill each week through a written description of the technique, video training, and hands-on practice (live animal vs. manikin). The following week, participants were scored on the performance of the previous week's skill on a live animal using a standardized rubric by reviewers blinded to the training group. Six weeks later, the assessment was repeated for all skills. Scores were compared between groups and time points using repeated-measures ANOVA after logarithmic transformation. p < .05 was significant. There were no significant differences in scores for any of the skills between the groups immediately following or 6 weeks after training. Initial proficiency and short-term retention of clinical skills do not differ for students trained using a manikin vs. a live dog.

Pharmacokinetics of orally administered single-dose ponazuril in cats.

Cats and kittens in animal shelters and catteries regularly suffer from severe gastrointestinal coccidiosis, which can be fatal, and there are no drugs labeled for feline coccidiosis in the United States. Ponazuril, a triazine-class drug, is increasingly used at a dose of 50 mg/kg/d, orally, for three to five days in shelter environments for coccidiosis. A single oral dose of ponazuril paste 15% (Marquis® ; Merial) at 50 mg/kg was administered to six healthy adult cats. Sample analysis was completed via high-performance liquid chromatography. Plasma concentrations peaked at 7.49 ± 2.06 µg/ml at 14.67 ± 7.45 hr post-administration. This study shows that ponazuril achieved a plasma concentration that inhibits growth of similar organisms after a single oral dose in cats. Further studies are necessary to optimize dosing for the treatment of clinical coccidiosis in cats.

Effects of Synbiotics on the Fecal Microbiome and Metabolomic Profiles of Healthy Research Dogs Administered Antibiotics: A Randomized, Controlled Trial.

Background: Antibiotic-associated gastrointestinal signs occurred in 100% of dogs administered enrofloxacin with metronidazole in a previous study, and signs partially were mitigated by synbiotics. The objective of this randomized, double-blinded, placebo-controlled trial was to compare the fecal microbiome and metabolome of dogs administered enrofloxacin and metronidazole, followed by either a placebo or a bacterial/yeast synbiotic combination. Methods: Twenty-two healthy research dogs were randomized to two treatment groups. There were three study periods: baseline, treatment, and washout. Dogs were administered enrofloxacin (10 mg/kg qd) and metronidazole (12.5 mg/kg BID), followed 1 h later by placebo or a commercially-available synbiotic combination (BID), per os for 21 days with reevaluation 56 days thereafter. Fecal samples were collected on days 5-7 (baseline), 26-28, and 82-84. The fecal microbiome was analyzed by qPCR and sequencing of 16S rRNA genes; time-of-flight mass spectrometry was used to determine metabolomic profiles. Split plot repeated measures mixed model ANOVA was used to compare results between treatment groups. P < 0.05 was considered significant, with Benjamini and Hochberg's False Discovery Rate used to adjust for multiple comparisons. Results: Alpha diversity metrics differed significantly over time in both treatment groups, with incomplete recovery by days 82-84. Beta diversity and the dysbiosis index differed significantly over time and between treatment groups, with incomplete recovery at days 82-84 for dogs in the placebo group. Significant group-by-time interactions were noted for 15 genera, including Adlercreutzia, Bifidobacterium, Slackia, Turicibacter, Clostridium (including C. hiranonis) [Ruminococcus], Erysipelotrichaceae_g_, [Eubacterium], and Succinivibrionaceae_g_. Concurrent group and time effects were present for six genera, including Collinsella, Ruminococcaceae_g_, and Prevotella. Metabolite profiles differed significantly by group-by-time, group, and time for 28, 20, and 192 metabolites, respectively. These included short-chain fatty acid, bile acid, tryptophan, sphingolipid, benzoic acid, and cinnaminic acid metabolites, as well as fucose and ethanolamine. Changes in many taxa and metabolites persisted through days 82-84. Conclusion: Antibiotic administration causes sustained dysbiosis and dysmetabolism in dogs. Significant group-by-time interactions were noted for a number of taxa and metabolites, potentially contributing to decreased antibiotic-induced gastrointestinal effects in dogs administered synbiotics.

Intrahistiocytic Storage of Clofazimine Crystals in a Cat.

A 13-year-old castrated male Maine coon cat with a 5-year history of atypical mycobacteriosis was euthanized and submitted for necropsy. The cat had been kept in clinical remission since diagnosis using a combination of the antimycobacterial drug clofazimine and additional multimodal antimicrobial therapy. Grossly, tissues were diffusely discolored red-brown to yellow. Histologically, the myocardial interstitum was expanded by numerous, often multinucleated cells, which were distended by uniformly shaped acicular cytoplasmic spaces. These cells were immunopositive for CD18 and immunonegative for desmin, suggesting a histiocytic rather than muscular origin. Macrophages in other tissues contained similar acicular spaces. Ultrastructurally, the spaces were surrounded by 2 lipid membranes, resembling an autophagosome. Based on the clinical history and histologic, immunohistochemical, and ultrastructural data, we diagnosed clofazimine crystal storage. To our knowledge, this is the first report of clofazimine storage in a cat or within myocardial interstitial macrophages.

Management of polyethylene glycol solution aspiration using bronchoscopic lavage in a dog.

Polyethylene glycol lavage solutions are used for colonic preparation in dogs and are considered relatively safe. Aspiration is an uncommon but potentially devastating complication of polyethylene glycol administration. Full recovery is possible and often rapid in people treated with bronchoalveolar lavage. A healthy 2-year-old male Beagle used in an endoscopy teaching laboratory aspirated a small amount of polyethylene glycol lavage solution. Although initially appearing unaffected, the dog quickly became hypoxemic. Bronchoscopy was used to lavage the lungs and aspirate tracheal/pulmonary fluid 5 times over the course of 45 minutes. The dog completely recovered. This report presents the successful treatment of polyethylene glycol aspiration in a dog. Although the seriousness of aspiration might not be immediately evident, bronchoscopy and lavage should be pursued because of the rapidly progressive nature of polyethylene glycol-induced pulmonary edema.

Effects of clopidogrel and prednisone on platelet function in healthy dogs.

BACKGROUND: Glucocorticoids cause hypercoagulability, but it is unknown if they counteract clopidogrel's antiplatelet effects. HYPOTHESIS/OBJECTIVES: Determine the effects of clopidogrel and prednisone on platelet function. ANIMALS: Twenty-four healthy dogs. METHODS: Double-blinded, placebo-controlled randomized trial. Platelet function was evaluated using a platelet function analyzer and impedance aggregometry (days 0, 14, and 28) for dogs treated with placebo, clopidogrel (2-3 mg/kg/d), prednisone (2 mg/kg/d), or prednisone with clopidogrel PO for 28 days. Results were categorized as nonresponder versus responder (platelet function analyzer), and inadequate, ideal, or excessive response (aggregometry). Results were compared using mixed model, split-plot repeated measures analysis of variance and generalized estimating equation proportional odds models. P < .05 was considered significant. RESULTS: Closure times differed by treatment (F [3, 20] = 10.5; P < .001), time (F [2, 40] = 14.3; P < .001), and treatment-by-time (F [6, 40] = 3.4; P = .01). Area under the curve (AUC) differed by treatment (F [3, 20] = 19.6; P < .001), time (F [2, 40] = 35.4; P < .001), and treatment-by-time (F [6, 40] = 13.5; P < .001). Based on closure times, 5/6 dogs each in the clopidogrel and prednisone/clopidogrel groups were responders. All dogs in the prednisone/clopidogrel group were overcontrolled based on AUC (days 14 and 28), whereas 5/6 (day 14) and 2/6 (day 28) dogs treated with clopidogrel were overcontrolled. Compared to clopidogrel, dogs receiving prednisone/clopidogrel were 11 times (P = .03) more likely to have an excessive response. CONCLUSIONS AND CLINICAL IMPORTANCE: Administration of clopidogrel/prednisone increases platelet dysfunction in healthy dogs.

Multicenter retrospective evaluation of ileocecocolic perforations associated with diagnostic lower gastrointestinal endoscopy in dogs and cats.

BACKGROUND: Ileoscopy is increasingly performed in dogs and cats with gastrointestinal signs, but iatrogenic ileocecocolic (ICC) perforations have not been described. HYPOTHESIS/OBJECTIVES: To characterize endoscopic ICC perforations in dogs and cats. ANIMALS: Thirteen dogs and 2 cats. METHODS: This is a retrospective case series. Signalment, presentation, endoscopic equipment, colonic preparation, endoscopist's experience level, ileal intubation technique, method of diagnosis, perforation location, histopathology, management, and outcome data were collected and reviewed. RESULTS: Six ileal, 5 cecal, and 4 colonic perforations were identified between 2012 and 2019. Dogs weighed 2.4-26 kg (median, 10.3 kg) and cats 4.6-5.1 kg (median, 4.9 kg). Endoscopy was performed in dogs presented for vomiting (n = 4), as well as large (n = 5), mixed (n = 4), and small (n = 1) bowel diarrhea. Cats had large bowel diarrhea. Endoscopists included 1 supervised intern, 9 supervised internal medicine residents (2 first year, 6 second year, 1 third year), and 5 internal medicine diplomates. Diagnosis was delayed in 5 dogs, occurring 1-5 days after endoscopy (median, 3 days); dogs were presented again with inappetence (n = 4), lethargy (n = 4), abdominal pain (n = 3), retching (n = 2), and syncope (n = 1). All animals underwent surgical correction. Histopathology did not identify lesions at the perforation site in any animal. Two dogs required a second surgery; 1 died 12 hours after surgery. Survival to discharge was 93%, with 78% surviving ≥8 months. CONCLUSIONS AND CLINICAL IMPORTANCE: Iatrogenic endoscopic ICC perforation is not indicative of underlying disease and is associated with a good prognosis. Delayed diagnosis can occur. Therefore, perforation should be considered in the differential diagnosis for animals with clinical deterioration after endoscopy.

Effects of Aspirin and Prednisone on Platelet Function and Thromboxane Synthesis in Healthy Dogs.

Glucocorticoid administration is a risk factor for thromboembolism in hypercoagulable dogs, and it is unknown if aspirin counteracts glucocorticoid-induced hypercoagulability. The objective was to determine the effects of sustained aspirin and prednisone administration on platelet function and thromboxane synthesis. Our hypothesis was that aspirin would consistently inhibit platelet function and thromboxane synthesis when administered with or without prednisone. In 24 healthy dogs, platelet aggregometry and urine 11-dehydro-thromboxane-B2 (11-dTXB2)-to-creatinine ratios were measured on days 0, 14, and 28. Dogs were administered placebos, aspirin (2 mg/kg/d), prednisone (2 mg/kg/d), or prednisone/aspirin combination therapy PO for 28 days in a randomized double-blinded study. Aspirin response was based on a >25% reduction in platelet aggregation compared to pre-treatment values. Results were compared using mixed model, split-plot repeated measures ANOVAs. P < 0.05 was considered significant. AUC differed significantly by time [F (2,40) = 10.2, P < 0.001] but not treatment or treatment-by-time. On day 14, 2 dogs were aspirin responders (aspirin, 1; placebo, 1). On day 28, 3 dogs were aspirin responders (aspirin, 2; prednisone/aspirin, 1). Urine 11-dTXB2-to-creatinine ratios differed significantly by group [F (3,20) = 3.9, P = 0.024] and time [F (2,40) = 8.7, P < 0.001), but not treatment-by-time. Post-hoc analysis revealed significant differences between aspirin and placebo groups (P=0.008), aspirin and prednisone/aspirin groups (P = 0.030), and placebo and prednisone groups (P = 0.030). In healthy dogs, sustained aspirin, prednisone, and combination therapy do not inhibit platelet aggregation, and when used as individual therapies, aspirin and prednisone decreased thromboxane synthesis. Additional studies using varied platelet function methodologies in hypercoagulable dogs are necessary.

Clinical, clinicopathologic, and gastrointestinal changes from administration of clopidogrel, prednisone, or combination in healthy dogs: A double-blind randomized trial.

BACKGROUND: Dogs with immune-mediated disease often receive glucocorticoids with clopidogrel, but ulcerogenic effects of current protocols are unknown. HYPOTHESIS/OBJECTIVES: To compare gastrointestinal endoscopic findings among dogs administered clopidogrel, prednisone, and combination treatment. ANIMALS: Twenty-four healthy research dogs. METHODS: Double-blinded, placebo-controlled randomized trial. Dogs received placebo, clopidogrel (2-3 mg/kg q24h), prednisone (2 mg/kg q24h), or prednisone with clopidogrel PO for 28 days. Attitude, food intake, vomiting, and fecal score were determined daily. Clinicopathologic testing was performed at baseline and on day 28. Gastrointestinal hemorrhages, erosions, and ulcers were numerated by 2 blinded investigators for endoscopies performed on days 0, 14, and 28, and endoscopic mucosal lesion scores were calculated. Results were compared using mixed model, split-plot repeated measures ANOVAs and generalized estimating equation proportional odds models as appropriate. P < .05 was considered significant. RESULTS: Clinical signs of gastrointestinal bleeding were not noted. Endoscopic mucosal lesion scores differed significantly by group (F[3, 20] = 12.8, P < .001) and time (F[2, 40] = 8.3, P < .001). Posthoc analysis revealed higher lesion scores in the prednisone-receiving groups (P ≤ .006 for each) and on day 14 (P ≤ .007 for each). Ulcers were identified in 4 dogs administered prednisone and 3 dogs administered prednisone/clopidogrel. Odds of having endoscopic mucosal lesion scores ≥4 were 7-times higher for dogs in prednisone (95%CI 1.1, 43.0; P = .037) and prednisone-clopidogrel (95%CI 1.1, 43.4; P = .037) groups than those in the placebo group. CONCLUSIONS AND CLINICAL IMPORTANCE: Gastrointestinal bleeding and ulceration occur commonly in healthy dogs administered prednisone or prednisone/clopidogrel treatment, but not clopidogrel monotherapy. Though lesions are severe in many cases, they are not accompanied by clinical signs.

Indirect Doppler flow systolic blood pressure measurements taken with and without headphones in privately-owned, conscious dogs.

OBJECTIVE: The purpose of this study was to assess the effect of headphone use and covariates on indirect radial Doppler flow systolic arterial blood pressure (BP) measurements in dogs. METHODS: Between May and August 2018, 100 privately-owned dogs were enrolled. Blood pressure was measured in lateral recumbency, with and without headphones, using a randomized crossover design. The initial BP, mean of BP 2-6, weight, BCS, MCS, anxiety score, and heart rate were recorded. Mixed effects crossover analyses and Spearman rank correlation coefficients were determined. RESULTS: Eighty-four dogs completed the study. Eleven dogs were removed due to excessive anxiety, 10 of which were in the non-headphone first group. The number of dogs diagnosed as hypertensive did not differ between measurement types (19 vs. 18), with seven dogs categorized as hypertensive during both periods. Significant differences in BP were identified (F[1, 80] = 4.3, P = 0.04) due to higher results for measurements taken without headphones for BP 1, but not BP 2-6. Systolic BP was positively correlated with anxiety score, age, and weight. CONCLUSIONS AND CLINICAL RELEVANCE: Though BP 1 was significantly higher when taken without headphones, this pattern did not persist for BP 2-6. Lack of association between BP 2-6 results and measurement type could reflect exclusion of dogs most sensitive to white coat hypertension, acclimation to technique, or improved sound quality of headphones. Given significantly higher BP 1 results and disproportionate exclusion of dogs due to anxiety when measurements first were taken without headphones, use of headphones is recommended to improve accuracy of results.

Clinical, clinicopathologic, and gastrointestinal changes from aspirin, prednisone, or combination treatment in healthy research dogs: A double-blind randomized trial.

BACKGROUND: Dogs with immune-mediated disease are often coadministered glucocorticoids and aspirin, but ulcerogenic effects of current protocols are unknown. OBJECTIVES: To compare gastrointestinal changes among dogs administered aspirin, prednisone, and combination treatment. ANIMALS: Twenty-four healthy research dogs. METHODS: Double-blinded, placebo-controlled randomized trial of dogs administered placebo, aspirin (2 mg/kg q24h), prednisone (2 mg/kg q24h), or combination treatment PO for 28 days. Clinical signs were recorded daily, with laboratory work performed at baseline and day 28. Gastrointestinal mucosal hemorrhages, erosions, and ulcers were numerated for endoscopic studies performed on days 0, 14, and 28; endoscopic mucosal lesion scores were calculated. Results were compared using mixed model repeated-measures analyses of variance and generalized estimating equation proportional odds models. P < .05 was considered significant. RESULTS: Gastric mucosal lesion scores differed by treatment-by-time (F[6, 40] = 4.4, P = .002), treatment (F[3, 20] = 7.1, P = .002), and time (F[2, 40] = 18.9, P < .001). Post hoc analysis revealed increased scores in the aspirin (day 14 only), prednisone, and prednisone/aspirin groups during treatment. Ulcers were identified on 14 studies, representing 10 dogs. Dogs receiving prednisone and prednisone/aspirin had 11.1 times (95% CI, 1.7-73.6) and 31.5 times (95% CI, 3.5-288.0) higher odds, respectively, of having endoscopic mucosal lesion scores ≥4 than dogs receiving placebo (P ≤ .01). CONCLUSIONS AND CLINICAL IMPORTANCE: Gastrointestinal bleeding occurs commonly in dogs administered aspirin, prednisone, or prednisone/aspirin treatment, with higher lesion scores for dogs receiving combination treatment. Even severe lesions are not accompanied by clinical signs.

Randomized, controlled, crossover trial of prevention of antibiotic-induced gastrointestinal signs using a synbiotic mixture in healthy research dogs.

BACKGROUND: Synbiotics decrease antibiotic-associated gastrointestinal signs (AAGS) in cats, but data supporting synbiotic use to ameliorate AAGS in dogs are lacking. OBJECTIVES: To determine if administration of synbiotics mitigates AAGS in dogs. ANIMALS: Twenty-two healthy research dogs. METHODS: Randomized, double-blinded, placebo-controlled, 2-way, 2-period, crossover study with an 8-week washout period. Each period included a 1-week baseline and 3-week treatment phase. Dogs received enrofloxacin (10 mg/kg PO q24h) and metronidazole (12.5 mg/kg PO q12h), followed 1 hour later by a bacterial/yeast synbiotic combination or placebo. Food intake, vomiting, and fecal score were compared using repeated-measures crossover analyses, with P < .05 considered significant. RESULTS: Hyporexia, vomiting, and diarrhea occurred in 41% (95% confidence interval [CI], 21-64), 77% (95% CI, 55-92), and 100% (95% CI, 85-100) of dogs, respectively, during the first treatment period. Derangements in food intake were smaller in both periods for dogs receiving synbiotics (F-value, 5.1; P = .04) with treatment-by-period interactions (F-value, 6.0; P = .02). Days of vomiting differed over time (F-value, 4.7; P = .006). Fecal scores increased over time (F-value, 33.5; P < .001), were lower during period 2 (F-value, 14.5; P = .001), and had treatment-by-period effects (F-value, 4.8; P = .04). CONCLUSIONS AND CLINICAL IMPORTANCE: Enrofloxacin/metronidazole administration is associated with a high frequency of AAGS. Synbiotic administration decreases food intake derangements. The presence of milder AAGS in period 2 suggests that clinical effects of synbiotics persist >9 weeks after discontinuation, mitigating AAGS in dogs being treated with antibiotics followed by placebo.

Characterization of Fungal Colonization of Indwelling Esophagostomy Tubes.

Fungal colonization of feeding tubes occurs rapidly in people, resulting in decreased structural integrity and complications such as luminal obstruction and tube failure. Esophagostomy tubes (E-tubes) are commonly used in dogs and cats for enteral support, but data are lacking regarding colonizing fungi and the impact of colonization on tube integrity. In this study, esophagostomy tubes were collected in lieu of disposal from dogs and cats undergoing feeding tube exchange. Fungi were isolated with culture and identified using morphological characteristics. Scanning electron microscopy was used to evaluate the surface characteristics of the tubes. Two silicone and one polyurethane E-tube were evaluated. Fungi associated with the normal microbiota, including Candida sp. and Penicillium sp., as well as environmental fungi were identified. This case series represents the first documentation of fungal colonization of silicone and polyurethane E-tubes in dogs and cats. Additionally, this is the first report to document degenerative changes in a silicone E-tube.

Effects of a synbiotic on the fecal microbiome and metabolomic profiles of healthy research cats administered clindamycin: a randomized, controlled trial.

Reduction in antibiotic-associated gastrointestinal signs (AAGS) in people co-administered probiotics is believed to result from shifts in the microbiome and metabolome. Amelioration of AAGS in cats secondary to synbiotic administration has recently been demonstrated. Thus, the aim of this randomized, double-blinded, placebo-controlled trial was to characterize associated changes in the fecal microbiome and metabolome. Sixteen healthy research cats received clindamycin with food, followed 1 h later by either a placebo or synbiotic, daily for 21 days. Fecal samples were collected during baseline, antibiotic administration, and 6 weeks after antibiotic discontinuation. Sequencing of 16S rRNA genes was performed, and mass spectrometry was used to determine fecal metabolomic profiles. Results were compared using mixed-model analyses, with P < 0.05 considered significant. Alpha and beta diversity were altered significantly during treatment, with persistent changes in the Shannon and dysbiosis indices. The relative abundance of Actinobacteria (Adlercreutzia, Bifidobacterium, Collinsella, Slackia), Bacteroidia (Bacteroides, Prevotella), Ruminococcaceae (Faecalibacterium, Ruminococcus), Veillonellaceae (Megamonas, Megasphaera, Phascolarctobacterium) and Erysipelotrichaceae ([Eubacterium]) decreased and relative abundance of Clostridiaceae (Clostridium) and Proteobacteria (Enterobacteriaceae) increased during treatment, followed by variable return to baseline relative abundances. Derangements in short-chain fatty acid (SCFA), bile acid, tryptophan, sphingolipid, polyamine, benzoic acid, and cinnaminic acid pathways occurred with significant group by time, group, and time interactions for 10, 5, and 106 metabolites, respectively. Of particular note were changes related to polyamine synthesis. Further investigation is warranted to elucidate the role of these alterations in prevention of AAGS in cats, people, and other animals treated with synbiotics.

Fatal pulmonary hemorrhage associated with vascular amyloid deposition in a cat.

CASE SUMMARY: An adult female spayed Siamese-cross cat of unknown age was presented for bilateral hemorrhagic otorrhea. Nasopharyngeal polyps were diagnosed by CT and biopsy; bilateral ventral bulla osteotomies were performed. Episodic epistaxis, otic hemorrhage and hemoptysis with respiratory distress progressed over 18 months. Systolic blood pressure, complete blood count, plasma biochemistries, prothrombin time, partial thromboplastin time and coagulation factor 12, 9 and 8 activities were normal. Serial thoracic radiographs revealed patchy interstitial to alveolar patterns. Airway hemorrhage prevented diagnostic bronchoscopy. Respiratory hemorrhage was ultimately fatal. Amyloid deposition was identified in pulmonary vasculature, bronchial wall, lymphoid tissues, nasal-pharyngeal tissue and tympanic bullae based on microscopic examination and confirmed by Congo red staining with green birefringence under polarized light. RELEVANCE AND NOVEL INFORMATION: Amyloidosis should be considered as a differential diagnosis in cats with spontaneous hemorrhage of the respiratory or otic tracts. Although systemic amyloidosis is associated with a grave prognosis, this case suggests that prolonged survival is possible after the initial onset of signs in cats with pulmonary amyloidosis.

Short and long-term effects of a synbiotic on clinical signs, the fecal microbiome, and metabolomic profiles in healthy research cats receiving clindamycin: a randomized, controlled trial.

BACKGROUND: Antibiotic-associated gastrointestinal signs (AAGS) occur commonly in cats. Co-administration of synbiotics is associated with decreased AAGS in people, potentially due to stabilization of the fecal microbiome and metabolome. The purpose of this double-blinded randomized-controlled trial was to compare AAGS and the fecal microbiome and metabolome between healthy cats that received clindamycin with a placebo or synbiotic. METHODS: 16 healthy domestic shorthair cats from a research colony were randomized to receive 150 mg clindamycin with either a placebo (eight cats) or commercially-available synbiotic (eight cats) once daily for 21 days with reevaluation 603 days thereafter. All cats ate the same diet. Food consumption, vomiting, and fecal score were recorded. Fecal samples were collected daily on the last three days of baseline (days 5-7), treatment (26-28), and recovery (631-633). Sequencing of 16S rRNA genes and gas chromatography time-of-flight mass spectrometry was performed. Clinical signs, alpha and beta diversity metrics, dysbiosis indices, proportions of bacteria groups, and metabolite profiles were compared between treatment groups using repeated measures ANOVAs. Fecal metabolite pathway analysis was performed. P < 0.05 was considered significant. The Benjamini & Hochberg's False Discovery Rate was used to adjust for multiple comparisons. RESULTS: Median age was six and five years, respectively, for cats in the placebo and synbiotic groups. Hyporexia, vomiting, diarrhea, or some combination therein were induced in all cats. Though vomiting was less in cats receiving a synbiotic, the difference was not statistically significant. Bacterial diversity decreased significantly on days 26-28 in both treatment groups. Decreases in Actinobacteria (Bifidobacterium, Collinsella, Slackia), Bacteriodetes (Bacteroides), Lachnospiraceae (Blautia, Coprococcus, Roseburia), Ruminococcaceae (Faecilobacterium, Ruminococcus), and Erysipelotrichaceae (Bulleidia, [Eubacterium]) and increases in Clostridiaceae (Clostridium) and Proteobacteria (Aeromonadales, Enterobacteriaceae) occurred in both treatment groups, with incomplete normalization by days 631-633. Derangements in short-chain fatty acid, bile acid, indole, sphingolipid, benzoic acid, cinnaminic acid, and polyamine profiles also occurred, some of which persisted through the terminal sampling timepoint and differed between treatment groups. DISCUSSION: Cats administered clindamycin commonly develop AAGS, as well as short- and long-term dysbiosis and alterations in fecal metabolites. Despite a lack of differences in clinical signs between treatment groups, significant differences in their fecal metabolomic profiles were identified. Further investigation is warranted to determine whether antibiotic-induced dysbiosis is associated with an increased risk of future AAGS or metabolic diseases in cats and whether synbiotic administration ameliorates this risk.