Prevalence of gastric lesions in racing Alaskan sled dogs

Analysis of the gut microbiome in sled dogs reveals glucosamine- and activity-related effects on gut microbial composition

The composition of the microbiome influences many aspects of physiology and health, and can be altered by environmental factors, including diet and activity. Glucosamine is a dietary supplement often administered to address arthritic symptoms in humans, dogs, and other mammals. To investigate how gut microbial composition varies with glucosamine supplementation, we performed 16S rRNA sequence analysis of fecal samples from 24 Alaskan and Inuit huskies and used mixed effects models to investigate associations with activity, age, and additional factors. Glucosamine ingestion, age, activity, sex, and diet were correlated with differences in alpha-diversity, with diversity decreasing in dogs consuming glucosamine. Beta-diversity analysis revealed clustering of dogs based on glucosamine supplementation status. Glucosamine supplementation and exercise-related activity were associated with greater inter-individual pairwise distances. At the family level, Lactobacillaceae and Anaerovoracaceae relative abundances were lower in supplemented dogs when activity was accounted for. At the genus level, Eubacterium [brachy], Sellimonus, Parvibacter, and an unclassified genus belonging to the same family as Parvibacter (Eggerthellaceae) all were lower in supplemented dogs, but only significantly so post-activity. Our findings suggest that glucosamine supplementation alters microbiome composition in sled dogs, particularly in the context of exercise-related activity.

Assessment of gastrointestinal health in racing Alaskan sled dogs using capsule endoscopy and inflammatory cytokines

OBJECTIVES

Exercise-induced gastrointestinal syndrome occurs in dogs and people and might compromise athlete performance by increasing intestinal permeability and causing gastrointestinal erosions. Racing sled dogs often receive acid suppressant prophylaxis which decreases the incidence of gastric erosions induced by exercise. The objectives were to quantify intestinal injury by measuring serum pro-inflammatory cytokine concentrations before and after exercise and to evaluate gastrointestinal mucosa using video capsule endoscopy after exercise.

MATERIALS AND METHODS

Prospective study of 12 racing Alaskan sled dogs receiving approximately 1 mg/kg omeprazole once daily from the day before the race until race completion. Blood was drawn before and 8 to 10 hours after an endurance race for the quantification of cytokines. Gastrointestinal tract mucosa was assessed with video capsule endoscopy immediately post-race.

RESULTS

Eight of nine dogs (89%; 95% confidence interval 52 to 100%) had gastric erosions; all dogs (100%, 95% confidence interval 63 to 100%) had small intestinal erosions. Most of the dogs (seven of nine) had straw or foreign material present. Cytokine levels were not different from before to after the race.

CLINICAL SIGNIFICANCE

Video capsule endoscopy identified gastrointestinal tract mucosal erosions after exercise in all dogs receiving once-daily omeprazole treatment, though other causes for the lesions besides exercise are possible.

Effects of a Saccharomyces cerevisiae fermentation product on fecal characteristics, metabolite concentrations, and microbiota populations of dogs subjected to exercise challenge

The objective of this study was to determine the fecal characteristics, microbiota, and metabolites of dogs fed a Saccharomyces cerevisiae fermentation product (SCFP) and subjected to exercise challenge in untrained and trained states. Thirty-six adult dogs (18 male, 18 female; mean age: 7.1 yr; mean body weight: 29.0 kg) were randomly assigned to control or SCFP-supplemented (250 mg/dog/d) diets and fed for 10 wk. After 3 wk, dogs were given an exercise challenge (6.5 km run), with fresh fecal samples collected pre- and post-challenge. Dogs were then trained by a series of distance-defined running exercise regimens over 7 wk (two 6.4 km runs/wk for 2 wk; two 9.7 km runs/wk for 2 wk; two 12.9 km runs/wk for 2 wk; two 3.2 km runs/wk). Dogs were then given exercise challenge (16 km run) in the trained state, with fresh fecal samples collected pre- and post-challenge. Fecal microbiota data were evaluated using QIIME2, while all other data were analyzed using the Mixed Models procedure of SAS. Effects of diet, exercise, and diet*exercise were tested with P < 0.05 considered significant. Exercise challenge reduced fecal pH and ammonia in both treatments, and in untrained and trained dogs. After the exercise challenge in untrained dogs, fecal indole, isobutyrate, and isovalerate were reduced, while acetate and propionate were increased. Following the exercise challenge in trained dogs, fecal scores and butyrate decreased, while isobutyrate and isovalerate increased. SCFP did not affect fecal scores, pH, dry matter, or metabolites, but fecal Clostridium was higher in controls than in SCFP-fed dogs over time. SCFP and exercise challenge had no effect on alpha or beta diversity in untrained dogs. However, the weighted principal coordinate analysis plot revealed clustering of dogs before and after exercise in trained dogs. After exercise challenge, fecal Collinsella, Slackia, Blautia, Ruminococcus, and Catenibacterium were higher and Bacteroides, Parabacteroides, Prevotella, Phascolarctobacterium, Fusobacterium, and Sutterella were lower in both untrained and trained dogs. Using qPCR, SCFP increased fecal Turicibacter, and tended to increase fecal Lactobacillus vs. controls. Exercise challenge increased fecal Turicibacter and Blautia in both untrained and trained dogs. Our findings show that exercise and SCFP may affect the fecal microbiota of dogs. Exercise was the primary cause of the shifts, however, with trained dogs having more profound changes than untrained dogs.

Military training-related abdominal injuries and diseases: Common types, prevention and treatment

Military training is intense, difficult and often dangerous, so all kinds of injuries or diseases frequently occur during training. Most of the previous studies and reviews on military training-related injuries focused on musculoskeletal system, whereas there are no reviews of abdominal injuries and diseases. Although the incidence of military training-related abdominal injuries and diseases is relatively low, the patients' condition is often critical especially in the presence of abdominal organ injury, leading to multi-organ dysfunction syndrome and even death. This paper elaborates on common types of military training-related abdominal injuries and diseases as well as the prevention and treatment measures, which provides some basis for scientific and reasonable training and improvement of medical security.

Clinical Features and Risk Factors for Gastrointestinal Complications in Dogs Treated Surgically for Thoracolumbar Intervertebral Disc Extrusion

Gastrointestinal (GI) complications and their clinical implications are poorly characterized in dogs treated surgically for acute thoracolumbar intervertebral disc extrusion (TL-IVDE). The objective of this retrospective study was to characterize GI signs (including vomiting, diarrhea, melena, and hematochezia) in dogs undergoing hemilaminectomy for acute TL-IVDE. One-hundred and sixteen dogs were included. Frequency, type and severity of GI signs during hospitalization, duration of hospitalization and outcome were obtained from the medical record. Potential risk factors for the development of GI signs were explored using univariable and multivariable analyses. Gastrointestinal signs occurred in 55/116 dogs (47%); 22/55 dogs (40%) had one episode and 21/55 (38%) had ≥5 episodes. Diarrhea was the most common (40/55, 73%) while melena was rare (1/55, 2%). GI signs developed in 8/11 dogs (73%) treated perioperatively with both non-steroidal anti-inflammatories and corticosteroids with or without a washout period and in 25/52 dogs (48%) treated prophylactically with proton pump inhibitors. Median hospitalization was 7 days (4-15 days) vs. 5 days (4-11 days) in dogs with or without GI signs, respectively. Duration of hospitalization was associated with development of any GI signs, diarrhea and more severe GI signs (p = 0.001, 0.005, 0.021, respectively). Pre-operative paraplegia with absent pain perception was identified on univariable analysis (p = 0.005) and longer anesthetic duration on multivariable analysis to be associated with development of more severe GI signs (p = 0.047). In dogs undergoing surgery for acute TL-IVDE, GI signs were common and associated with duration of hospitalization and anesthesia. The influence of specific medications and neurologic severity on development of GI signs requires further investigation.

Efficacy of Nx4 to Reduce Plasma Cortisol and Gastrin Levels in Norwegian Sled Dogs During an Exercise Induced Stress Response: A Prospective, Randomized, Double Blinded, Placebo-Controlled Cohort Study

Introduction: An exercise induced stress response is commonly seen in high performance sled dogs, resulting in increased plasma cortisol. A stress induced rise of cortisol might result in increased prevalence of gastritis and gastric ulcers mediated by an increase of gastrin. Neurexan^® (Nx4) is a medicinal product used for stress relief by reduction of cortisol. The aim of the study was to show that Nx4 reduces plasma cortisol and plasma gastrin in high performance sled dogs and to show tolerability of Nx4 in dogs.

Material and Methods: First, a pilot study was done to validate the increase of cortisol by performance. The data from the pilot study was used for sample size estimation via an adapted power analysis as well as the identification of important variables. These were then used in the randomization procedure of the main study. Second, a prospective randomized, double blinded, placebo-controlled cohort study was conducted. The main study included 45 sled dogs, assigning 23 dogs to the Nx4 group, and 22 dogs to the placebo group, to analyze plasma cortisol and plasma gastrin at four time points: before, directly after and 30 and 120 min after performance.

Results: For the main target variable, area under the curve (AUC) of plasma cortisol, a significantly lower adjusted mean value in the Nx4 group compared to the placebo group (p = 0.031) was found. Plasma gastrin was also significantly reduced in the Nx4 group 30 min after performance (p = 0.023), resulting in a significantly reduced plasma gastrin AUC in the Nx4 group compared to the placebo group (p = 0.049).

Discussion: Within the limitation of the study, the results carry implications for the usefulness of Nx4 to reduce exercise induced plasma cortisol and gastrin levels. The reduction of the exercise induced stress response could help to improve the welfare of high-performance sled dogs. Since activation of the hypothalamic-pituitary-adrenal axis resulting in increased cortisol is similar for exercise induced stress and psychologic stress, the same might be true independent of the stressor, making Nx4 potentially useful in any stressful situation for dogs.

Medical conditions associated with gastroduodenal ulceration or erosion in 168 dogs: 2008-2018

Background

Many medical conditions are thought to cause gastroduodenal ulceration or erosion (GUE) in dogs. However, evidence for the association between many of these conditions and GUE in dogs is lacking.

Objective

To identify medical conditions associated with GUE in dogs.

Animals

One hundred and sixty‐eight dogs with GUE and 168 randomly selected control dogs without evidence of GUE identified on necropsy between January 2008 and September 2018.

Methods

Patient signalment, blood urea nitrogen (BUN) and serum creatinine concentrations, recently administered ulcerogenic drugs, as well as necropsy findings were recorded. The association between these findings and presence of GUE was assessed by univariable and multivariable analysis.

Results

In the final multivariable model, the following factors were associated with GUE: Nonsteroidal anti‐inflammatory drug (NSAID) administration (odds ratio [OR], 6.3; 95% confidence interval [CI], 2.3‐17.4; P = .0004), glucocorticoid administration (OR, 3.0; 95% CI, 1.5‐5.9; P = .001), gastrointestinal neoplasia (OR, 13.5; 95% CI, 1.7‐108.0; P = .01) and gastrointestinal mechanical disease (foreign bodies, gastric dilatation, and volvulus; OR, 4.8; 95% CI, 1.2‐19.7; P = .03). Additionally, working dog breeds were predisposed to GUE compared to mixed breed dogs (OR, 2.8; 95% CI, 1.1‐7.4; P = .04). Insufficient clinical data was available to either support or refute a role of other putative risk factors evaluated.

Conclusion and Clinical Importance

Administration of NSAID or glucocorticoid and gastrointestinal neoplasia or mechanical disease were associated with GUE in dogs. The potential predisposition of working breed dogs for GUE requires further investigation.

A comparative time-dependent study of hematology, serum gastrin concentrations, and gastroscopic assessment of meloxicam-induced gastric ulceration in dogs

Background

Diagnosis of gastric ulcers by methods other than gastroscopy in dogs has been problematic for many years and biomarkers such as serum gastrin (SG) concentrations have been introduced as a noninvasive way to evaluate gastric diseases.

Objectives

To determine the time course changes in hematology, SG concentrations, and gastroscopic images of meloxicam‐induced gastric ulceration in dogs and identify a relationship between SG and gastroscopic image analysis in a clinical setting.

Animals

Fifteen crossbreed dogs.

Methods

Two groups: control (n = 5) and meloxicam‐treated (n = 10). The meloxicam‐treated group received meloxicam 0.2 mg/kg PO for 15 days. Clinical signs, hematology, SG, and image analysis (PI, pixel intensity; ID, integrated density; RA, relative area; and UI, ulcer index) of the gastroscopic examination were evaluated across time (T5, time 5 day; T10, time 10 day; and T15, time 15 day).

Results

Significant changes were observed among 3 time points and between the 2 groups in terms of SG, hematology, and gastroscopic image analysis. In the meloxicam‐treated group, decreases in hemoglobin concentration, red blood cell count and packed cell volume at T10 and T15 (P = .0001) were observed, whereas SG, ID, and UI increased over time (P < .0001). The PI decreased significantly (P = .0001) in the meloxicam‐treated group compared to controls. Significant correlations were found between SG and PI, and ID and ulcer area (r = −0.89, 0.81, 0.64), respectively.

Conclusion and Clinical Importance

Gastroscopy is the gold standard for early descriptive diagnosis of gastric ulcerations in dogs, and SG is a good indicator for meloxicam‐induced gastric ulcers in dogs and can predict the gastroscopic score of the lesion.

Prevalence of gastrointestinal lesions in dogs chronically treated with nonsteroidal anti-inflammatory drugs

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most common pharmaceutical associated with gastroduodenal ulceration and perforation. The prevalence of gastrointestinal (GI) injury associated with chronic use of NSAIDs in dogs is unknown.

OBJECTIVE/HYPOTHESIS

To determine the prevalence of GI mucosal erosions in dogs receiving chronic treatment with NSAIDs. We hypothesized that dogs receiving NSAIDs would have more GI mucosal erosions and longer GI transit time than a control population.

ANIMALS

Fourteen client-owned medium- and large-breed dogs receiving an NSAID for at least 30 days and 11 client-owned control dogs undergoing video capsule endoscopy (VCE) for evaluation of chronic GI disease.

METHODS

Dogs were prospectively recruited after determining no clinically relevant comorbidities were present and VCE was performed. The GI transit time and the presence of mucosal lesions were recorded.

RESULTS

Twelve dogs receiving NSAIDs and 11 retrospectively evaluated control dogs were included. The NSAIDs administered included carprofen (9 dogs), meloxicam (2 dogs), and firocoxib (1 dog) for a median of 6 months. Ten (83.3%; 95% confidence interval; 51.6%-97.9%) NSAID-treated dogs had GI erosions. Erosions were seen with all 3 NSAIDs in at least 1 dog. Three of 11 control dogs had gastric erosions. Dogs receiving NSAIDs had more erosions detected (P = .004).

CONCLUSIONS AND CLINICAL RELEVANCE

Subclinical GI erosions are more common in dogs receiving chronic treatment with NSAIDs than in control dogs with chronic GI disease, suggesting that NSAIDs be used with caution, particularly in dogs with comorbidities predisposing them to GI ulceration.

The effect of age and sex on selected hematologic and serum biochemical analytes in 4,804 elite endurance-trained sled dogs participating in the Iditarod Trail Sled Dog Race pre-race examination program

Endurance-trained sled dogs provide a unique translational model to characterize changes in hematologic and serum biochemical analytes due to the aging process. The primary objective of this study was to determine the effect of age and sex on specific hematologic and serum biochemical parameters in the endurance trained sled dog. Longitudinal and cross-sectional data were analyzed from 9,746 blood and serum samples from 4,804 dogs collected over 7 years as part of the Iditarod Trail Sled Dog Race pre-race examination program. Mixed models analysis was used for statistical analysis and P < 0.01 was considered significant. Dogs ranged from 1–12 years of age and 39% were female. Serum total calcium and phosphorus concentrations and white blood cell count decreased nonlinearly to asymptotic values by 6.6, 3.1, and 6.9 years of age, respectively, equivalent to estimated physiologic ages in human years of 44, 27, and 46 years. Serum glucose concentrations reached their lowest value at 7.8 years of age, equivalent to an estimated human physiologic age of 50 years, after which time the concentration increased. Serum globulin concentrations increased with age, but nonlinearly for females and linearly for males. Most sex-related differences were <5%; however, females had lower serum urea nitrogen (14.7%) and creatinine (7.3%) concentrations, lower serum alanine aminotransferase activity (16.6%), and higher serum total bilirubin concentration (12.8%) and platelet count (6.0%). The endurance-trained sled dog provides an excellent model to separate the physiologic effects of age from those of a sedentary lifestyle on hematologic and serum biochemical analytes.

Non-invasive Assessment of Fecal Stress Biomarkers in Hunting Dogs During Exercise and at Rest

Intense exercise causes to organisms to have oxidative stress and inflammation at the gastrointestinal (GI) level. The reduction in intestinal blood flow and the exercise-linked thermal damage to the intestinal mucosa can cause intestinal barrier disruption, followed by an inflammatory response. Furthermore, the adaptation to exercise may affect the gut microbiota and the metabolome of the biofluids. The aim of the present research was to evaluate the presence of a GI derangement in hunting dogs through a non-invasive sampling as a consequence of a period of intense exercise in comparison with samples collected at rest. The study included nine dogs that underwent the same training regime for hunting wild boar. In order to counterbalance physiological variations, multiple-day replicates were collected and pooled at each experimental point for each dog. The samples were collected immediately at rest before the training (T0), after 60 days of training (T1), after 60 days of hunting wild boar (T2), and finally, at 60 days of rest after hunting (T3). A number of potential stress markers were evaluated: fecal cortisol metabolites (FCMs) as a major indicator of altered physiological states, immunoglobulin A (IgA) as an indicator of intestinal immune protection, and total antioxidant activity [total antioxidant capacity (TAC)]. Since stool samples contain exfoliated cells, we investigated also the presence of some transcripts involved in GI permeability [occludin (OCLN), protease-activated receptor-2 (PAR-2)] and in the inflammatory mechanism [interleukin (IL)-8, IL-6, IL-1b, tumor necrosis factor alpha (TNFα), calprotectin (CALP), heme oxygenase-1 (HO-1)]. Finally, the metabolome and the microbiota profiles were analyzed. No variation in FCM and IgA content and no differences in OCLN and CALP gene expression between rest and training were observed. On the contrary, an increase in PAR-2 and HO-1 transcripts, a reduction in total antioxidant activity, and a different profile of microbiota and metabolomics data were observed. Collectively, the data in the present study indicated that physical exercise in our model could be considered a mild stressor stimulus.

Haematological and serum biochemical values in Norwegian sled dogs before and after competing in a 600 km race

Background

Long-distance racing is known to cause alterations in haematological and serum biochemical parameters in sled dogs. Given that finishing status reflects the physical condition in dogs completing a race, such variations will mainly be the result of physiological adaption achieved during endurance exercise. However, changes observed in withdrawn dogs may indicate pathological conditions. The aim of this study was to reveal changes in haematological and serum biochemical values in sled dogs participating in a long-distance race, with emphasis on the withdrawn dogs. Sixty-five sled dogs participated in a clinical prospective cohort study: 46 dogs competed in the 600 km race (25 finishing and 21 withdrawn dogs), and 19 dogs served as controls. Blood sampling was performed early in the training season and after the race.

Results

When compared to control dogs, both withdrawn and finishing dogs showed significant increases in neutrophil count, C-reactive protein, blood urea nitrogen and sodium/potassium ratio. Significant decreases were found in erythrocytes and eosinophil cell count, and in haematocrit, haemoglobin, total protein, albumin, globulin, creatinine, potassium and calcium levels. Finishing dogs presented significant increases in white blood cells, large unstained cells, monocyte count and cortisol level compared to control dogs. In contrast, withdrawn dogs had significant elevations in alanine aminotransferase and alkaline phosphatase activity, as well as parameters associated with muscle metabolism, such as aspartate aminotransferase, creatine kinase and phosphorus concentration.

Conclusions

Competing sled dogs experienced minor changes in blood parameters in general, mainly revealing the same pattern among withdrawals and finishers. This might indicate that numerous changes simply reflect physiological adaption due to endurance exercise. However, the serum concentration of muscle enzymes was significantly increased only in the withdrawals, and were well above reference ranges. This reflects muscle degradation, which could be the main cause of performance failure in some of the withdrawals.

Electronic supplementary material

The online version of this article (10.1186/s13028-019-0453-5) contains supplementary material, which is available to authorized users.

Psychogenic stress in hospitalized veterinary patients: Causation, implications, and therapies

OBJECTIVE

To review the sources, adverse effects, diagnosis, treatment, and prevention of psychogenic stress in hospitalized human and veterinary patients.

DATA SOURCES

Data were collected by searching PubMed for veterinary and human literature from the past 10 years.

HUMAN DATA SYNTHESIS

Psychogenic stress has been linked to immune suppression; gastrointestinal, cardiovascular, and cutaneous diseases; delayed wound healing; alterations in pain perception; and neurologic impairment. Sources of psychogenic stress include environmental alterations such as excessive noise and light, social and physical factors, sleep disruption, drugs, and underlying disease. Nonpharmacologic options for stress reduction include environmental and treatment modifications, music therapy, and early mobilization. Pharmacologic options include sedation with benzodiazepines and dexmedetomidine. Trazodone and melatonin have been examined for use in sleep promotion but are not currently recommended as standard treatments in ICU.

VETERINARY DATA SYNTHESIS

Activation of the stress response in veterinary patients is largely the same as in people, as are the affected body systems. Possible sources of stress can include social, physical, and environmental factors. No gold standard currently exists for the identification and quantification of stress. A combination of physical examination findings and the results of serum biochemistry, CBC, and biomarker testing can be used to support the diagnosis. Stress scales can be implemented to identify stressed patients and assess severity. Nonpharmacologic treatment options include low-stress handling, pheromones, environmental modifications, and sleep promotion. Pharmacologic options include trazodone, benzodiazepines, dexmedetomidine, and melatonin.

CONCLUSION

The prevalence and clinical significance of psychogenic stress in hospitalized veterinary patients is unknown. Future studies are needed to specifically examine the causative factors of psychogenic stress and the effects of various therapies on stress reduction. The recognition and reduction of psychogenic stress in veterinary patients can lead to improvements in patient care and welfare.

Effects of Short-Distance Recreational Mushing on Oxytocin, Gastrin, and Creatinine Kinase in Sled Dogs

A considerable increase in creatinine kinase (CK) activity and gastrin hormone due to exercise has been observed in sled dogs during endurance mushing races; however, there have been no studies on sled dogs during recreational mushing. Although oxytocin hormone is involved in social behaviors and empathy, it has not been studied in sled dogs. This study aimed to assess changes in plasma CK activity, and gastrin and oxytocin concentrations in adult sled dogs used in touristic mushing in North Patagonia, Argentina. Blood samples were collected before, during, and after the winter season of 2017. Creatinine kinase activity measurement was done using an enzymatic assay. Hormone analyses were performed using commercial Enzyme-Linked InmunoSorbent Assay kits. Results showed an expected two-fold increase in CK activity during the winter, with recovering basal values after winter (< 400 UI/L), low and stable levels of gastrin (9.4 ± 8.8 pg/mL), and a slight increase in oxytocin (23%) after mushing activities. No evidence indicated gastrin alterations or muscular damage from touristic mushing, but an oxytocin increase would indicate a stimulation of the brain reward system.

Effect of sucralfate on gastric permeability in an ex vivo model of stress-related mucosal disease in dogs

BACKGROUND

Sucralfate is a gastroprotectant with no known systemic effects. The efficacy of sucralfate for prevention and treatment of stress-related mucosal diseases (SRMD) in dogs is unknown.

HYPOTHESIS/OBJECTIVES

To develop a canine ex vivo model of SRMD and to determine the effect of sucralfate on mucosal barrier function in this model.

ANIMALS

Gastric antral mucosa was collected immediately postmortem from 29 random-source apparently healthy dogs euthanized at a local animal control facility.

METHODS

Randomized experimental trial. Sucralfate (100 mg/mL) was applied to ex vivo canine gastric mucosa concurrent with and after acid injury. Barrier function was assessed by measurement of transepithelial electrical resistance (TER) and radiolabeled mannitol flux.

RESULTS

Application of acidified Ringers solution to the mucosal side of gastric antrum caused a reduction in gastric barrier function, and washout of acidified Ringers solution allowed recovery of barrier function (TER: 34.0 ± 2.8% of control at maximum injury, 71.3 ± 5.5% at recovery, P < .001). Sucralfate application at the time of injury or after injury significantly hastened recovery of barrier function (TER: 118.0 ± 15.2% of control at maximum injury, P < .001 and 111.0 ± 15.5% at recovery, P = .35).

CONCLUSIONS AND CLINICAL IMPORTANCE

Sucralfate appeared effective at restoring defects in gastric barrier function induced by acid and accelerating repair of tissues subjected to acid in this model, suggesting that sucralfate could have utility for the treatment and prevention of SRMD in dogs.

Multiple gastric erosions diagnosed by means of capsule endoscopy in a dog

CASE DESCRIPTION A 6-year-old spayed female Golden Retriever was evaluated for a 2-week history of progressive hyporexia, signs of abdominal pain, and weight loss. CLINICAL FINDINGS Physical examination findings included mild signs of pain on palpation of the cranial part of the abdomen and a body condition score of 4 (scale, 1 to 9). A CBC revealed mild microcytosis and hypochromasia; results of serum biochemical analysis were within the respective reference ranges, and abdominal ultrasonography revealed no abnormalities. Capsule endoscopy was performed, and numerous gastric erosions and hemorrhages were detected, with rare dilated lacteals in the proximal aspect of the small intestine. TREATMENT AND OUTCOME Treatment was initiated with omeprazole and sucralfate for 6 weeks, and the dog was transitioned to a novel protein diet. Capsule endoscopy was repeated at the end of the initial treatment course and revealed overall improvement, with a few small erosions remaining; medical treatment was continued for an additional 2 weeks. At last follow-up 9 months after treatment ended, the dog was clinically normal. CLINICAL RELEVANCE Capsule endoscopy was useful for initial detection and subsequent reevaluation of gastrointestinal lesions in this patient without a need for sedation or anesthesia. Information obtained in the follow-up evaluation was valuable in identifying a need to extend the duration of medical treatment.

Continuous radiotelemetric monitoring of intragastric pH in a dog with peptic ulceration

CASE DESCRIPTION A 6-year-old castrated male Boxer was evaluated for a 5-week history of frequent vomiting, melena, and signs of abdominal pain following accidental ingestion of 5 to ten 15-mg meloxicam tablets (approx ingested dose, 3.1 to 6.2 mg/kg [1.4 to 2.8 mg/lb]). CLINICAL FINDINGS Clinical signs persisted despite 3 weeks of treatment with sucralfate (41.8 mg/kg [19 mg/lb], PO, q 8 h) and omeprazole (0.8 mg/kg [0.36 mg/lb], PO, q 24 h). Results of a CBC and serum biochemical analysis were unremarkable. Abdominal ultrasonography revealed peptic ulceration, and esophagogastroduodenoscopy confirmed the presence of severe proximal duodenal ulceration. TREATMENT AND OUTCOME A radiotelemetric pH-monitoring capsule was placed in the gastric fundus under endoscopic guidance for continuous at-home monitoring of intragastric pH and response to treatment. Treatment was continued with sucralfate (as previously prescribed) and omeprazole at an increased administration frequency (0.8 mg/kg, PO, q 12 h). Intragastric pH was consistently ≥ 3.0 for > 75% of the day during treatment, with the exception of 1 day when a single dose of omeprazole was inadvertently missed. Ulceration and clinical signs completely resolved. CLINICAL RELEVANCE Continuous radiotelemetric monitoring of intragastric pH in the dog of this report was useful for confirming that treatment achieved a predetermined target pH and for demonstrating the impact of missed doses. Duodenal ulceration resolved with twice-daily but not once-daily omeprazole administration. Findings suggested that twice-daily administration of omeprazole may be necessary to achieve this target pH and that a pH ≥ 3.0 for 75% of the day may promote healing of peptic ulcers in dogs.

Gastroduodenal Ulceration in Small Animals: Part 1. Pathophysiology and Epidemiology

Gastroduodenal ulceration in small animals is a complex and important comorbidity that occurs when the physiological homeostasis of the gastrointestinal tract is disrupted secondary to administration of medications or the presence of local or systemic diseases. The aim of this article is to provide a comprehensive review of the veterinary literature regarding the pathophysiology, epidemiology, and risk factors associated with gastroduodenal ulceration in small animals. Pertinent concepts from the human literature will be integrated into the discussion. This article serves as an introduction to the second part of this series, which will review current evidence regarding the use of H2-receptor antagonists and proton pump inhibitors in small animals.

Gastroduodenal Ulceration in Small Animals: Part 2. Proton Pump Inhibitors and Histamine-2 Receptor Antagonists

In the first part of this review, we discussed the pathophysiology and epidemiology of gastric acid secretion and the epidemiology of gastroduodenal ulceration in dogs and cats. In this section, we discuss the pharmacology and evidence-based clinical use of histamine-2 receptor antagonists and proton pump inhibitors.

Influence of exhaustive aerobic exercise on some cytokines and serum iron parameters in canine experimental model

The aim of the experiment was to study the effect of exhaustive exercise on some cytokines and iron status parameters. We used 12 male, mongrel dogs divided into two groups – animals from experimental group were submitted to exercise at moderate intensity with exhaustion as the end-point; animals from control group did no exercise. Serum levels of tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), hepcidin prohormone, serum iron (SI), total iron binding capacity (TIBC) and transferrin saturation (TS) were measured before exercise (BE), right after exercise (0 hour) and on 2, 4, 24, 48 and 72 hours after exercise. SI, TIBC and TS were measured also on day 7 and 14 after exercise. Serum levels of TNF-α increased after the exhaustive exercise. Serum levels of IL-6 demonstrated an increase at 0 hour, but increase was not statistically significant compared to BE level. Serum levels of hepcidin prohormone marked a slight increase 48 hours after the exercise, but change was insignificant. Levels of SI decreased on hour 72 (P<0.01) and on day 7 (P<0.01) and 14 (P<0.05) after the exercise, as compared to BE level. Similar were changes in TS. TIBC decreased on 4, 24 and 72 hours (P<0.05) after exercise, but only compared to control group. In conclusion, exhaustive exercise causes inflammatory response and a significant decrease in SI levels.

Serum concentration of gastrin, cortisol and C-reactive protein in a group of Norwegian sled dogs during training and after endurance racing: a prospective cohort study

Background

High incidences of gastritis and gastric ulceration are observed in sled dogs participating in endurance races. Exercise-induced increases in hormones like gastrin and cortisol have been suggested as possible contributing factors. An increase in C-reactive protein (CRP) has also been observed in canines during physical exercise. The aim of this study was to evaluate the effect of long distance racing on the serum concentration of gastrin, cortisol and CRP in a group of sled dogs, by comparing the results achieved early in the training season and after participating in a long distance race; “Femundløpet”. Dogs that only trained to the race, but did not compete in the race, were used as control dogs. Sixty-five sled dogs participated in the study; 46 competing dogs (25 completing and 21 non-completing the race) and 19 non-racing dogs (control dogs). The blood samples were collected in October 2012 and February 2013.

Results

The post-race serum concentration of gastrin, cortisol and CRP was significantly elevated in sled dogs participating in the race (both completing and non-completing dogs) when compared to the results from training. However, no significant differences were observed between the two sampling dates in the control dogs. Post-race results for completing and non-completing dogs were also compared. This demonstrated a significant elevation in gastrin in non-completing versus completing dogs, and a significant elevation in cortisol in completing compared to non-completing dogs.

Conclusions

Participation in a long distance race was associated with a significant increase in serum gastrin, cortisol and CRP in sled dogs.

Electronic supplementary material

The online version of this article (doi:10.1186/s13028-016-0204-9) contains supplementary material, which is available to authorized users.

Gastritis and Gastric Ulcers in Working Dogs

Gastritis and gastric ulcers are an important cause of morbidity and mortality in canine athletes. Although the majority of scientific work on this condition has been performed in ultraendurance racing sled dogs, this condition has been identified in other canine athletes, including sled dogs competing in shorter events and dogs performing off-leash explosive detection duties. The cause of the syndrome is unknown, but current hypotheses propose a link between exercise-induced hyperthermia and loss of gastric mucosal barrier function as an early event in the pathogenesis. Treatment is focused on prevention of clinical disease using acid secretion inhibitors, such as omeprazole, which has excellent efficacy in controlled clinical studies.

Effect of exercise on gastric health in field retrievers

Exercise-induced gastrointestinal disease (EIGD) has been reported in all domestic athletes. In dogs and humans, EIGD is most commonly associated with ultra-endurance racing sled dogs and marathon/triathlon competitors, respectively, suggesting that the syndrome is specifically a function of prolonged exercise. However, EIGD is also common in horses that exercise for brief periods, and more recently, EIGD has been identified in Labrador retrievers that perform off-leash explosive detection patrols. In this study, we tested the hypothesis that EIGD could be induced in retrievers performing competition-style retrieves. Gastric endoscopy and histopathological examination of gastric biopsies were performed on 10 healthy retrievers before and 24 h after a series of multi-set retrieves totalling over 5 km. Although the exercise challenge resulted in a small but statistically significant increase in gastric endoscopy severity score, it did not result in a higher prevalence of clinically-significant gastric disease or changes in gastric histopathology. We conclude that competitive retrieving is unlikely to induce clinically-significant gastric disease in healthy dogs.

Canine Gastric Pathology: A Review

Gastric disorders are common in dogs and are a major reason for veterinary consultation. In human medicine, the classification of gastric diseases based on histological features, genotypes and molecular phenotypes helps to better understand the characteristics of each subtype, and to improve early diagnosis, prevention and treatment. Canine gastric lesions often show strong histological similarities to their human counterparts. However, such conditions in the canine stomach are poorly studied and their cellular and molecular features are largely unknown. This article reviews the histopathological classification of inflammatory and neoplastic lesions of the canine stomach and provides an update on the application of molecular techniques within the field of canine gastric pathology. The canine disorders are compared with current knowledge of the equivalent human diseases.

Prevalence and risk factors for development of hemorrhagic gastro-intestinal disease in veterinary intensive care units in the United Kingdom

OBJECTIVE

To determine the prevalence of hemorrhagic gastro-intestinal (GI) disease developing in dogs and cats admitted for management of non-GI disease in veterinary intensive care units (ICUs).

DESIGN

Retrospective study of animals presented between October 2012 and July 2013.

SETTING

Three ICUs located in veterinary teaching hospitals in the United Kingdom.

ANIMALS

Dogs (n = 272) and cats (n = 94) were consecutively enrolled from 3 ICUs if they were hospitalized in the unit for at least 24 hours. Cases were excluded if they had hemorrhagic GI disease in the 48-hour period before presentation or in the 24-hour period after admission. Cases were also excluded if they suffered skull fracture, epistaxis, or hemoptysis, if they underwent surgical procedures of the GI or upper respiratory tracts, or if they were presented for management of GI disease.

MEASUREMENTS AND MAIN RESULTS

Hemorrhagic GI disease was observed in dogs at all 3 units, but at different rates (Center 1: 10.3%, Center 2: 4.8%, Center 3: 2.2%). Hemorrhagic GI disease was not observed in cats at any of the participating centers. Construction of a multivariable logistic regression model revealed that serum albumin concentration, administration of prophylactic gastro-protectant drugs, and institution were significantly associated with the development of hemorrhagic GI disease in dogs. Development of hemorrhagic GI disease and placement of a feeding tube were significantly associated with mortality during the period of hospitalization in dogs. Thirty-seven (13.6%) dogs and 12 (12.8%) cats died or were euthanized while hospitalized, with a higher mortality rate (42.1%) in dogs with hemorrhagic GI disease.

CONCLUSIONS

Hemorrhagic GI disease does develop in dogs hospitalized for management of non-GI disease, but this phenomenon was not observed in cats. Development of hemorrhagic GI disease appeared to have a significant impact on survival in veterinary ICUs.

Psychogenic Stress in Hospitalized Dogs: Cross Species Comparisons, Implications for Health Care, and the Challenges of Evaluation

Simple Summary

The effects of stress on health outcomes in animals are well documented. Veterinary clinicians may be able to improve their patients’ care by better understanding how to recognize and reduce stress in those patients. This review will describe the physiology of the mammalian stress response and known health consequences of psychogenic, rather than physical, stress; as well as methods of measuring stress in animals. While the review will address stress in a range of domestic species, it will specifically focus on dogs.

Abstract

Evidence to support the existence of health consequences of psychogenic stress has been documented across a range of domestic species. A general understanding of methods of recognition and means of mitigation of psychogenic stress in hospitalized animals is arguably an important feature of the continuing efforts of clinicians to improve the well-being and health of dogs and other veterinary patients. The intent of this review is to describe, in a variety of species: the physiology of the stress syndrome, with particular attention to the hypothalamic-pituitary-adrenal axis; causes and characteristics of psychogenic stress; mechanisms and sequelae of stress-induced immune dysfunction; and other adverse effects of stress on health outcomes. Following that, we describe general aspects of the measurement of stress and the role of physiological measures and behavioral signals that may predict stress in hospitalized animals, specifically focusing on dogs.

Reticulocytosis in nonanemic dogs: increasing prevalence and potential etiologies

BACKGROUND

An increasing prevalence of reticulocytosis in the absence of anemia (RAA) in dogs has been suspected in recent years.

OBJECTIVES

The objectives were to determine whether prevalence of RAA in our canine population has been increasing over the last years, and to identify potential predisposing factors.

METHODS

The annual prevalence of RAA in adult dogs was determined between 2000 and 2012. Clinical histories and CBC data were analyzed for all dogs, as well as owner response to a questionnaire including information on nutrition and supplements was conducted for dogs with RAA identified between 2011 and 2012. In addition, serum iron concentration (Fe), total iron-binding capacity (TIBC), and percent transferrin saturation (%TS) were determined in 14 dogs with RAA and compared with 8 healthy control dogs.

RESULTS

Reticulocytosis in the absence of anemia was identified in 1035 dogs, with the prevalence increasing since 2006. Dogs with RAA evaluated after 2006 (n = 853) had significantly lower MCV and were more likely to have microcytosis than those prior to 2006 (n = 182). Increased incidence of osteoarthritis was observed in dogs evaluated after 2006, including the dogs studied between 2011 and 2012 (n = 31), and administration of nonsteroidal anti-inflammatory drugs, omega-3 fatty acids, and glucosamine was more common in the latter. Significantly lower mean Fe and %TS, and higher TIBC were found in dogs with RAA compared to unaffected dogs.

CONCLUSIONS

Prevalence of RAA has increased in recent years in our canine population. More ubiquitous use of anti-inflammatory medications and nutraceuticals, associated with increased diagnosis of osteoarthritis should be considered as contributing factors.

Exercise induced hypercoagulability, increased von Willebrand factor and decreased thyroid hormone concentrations in sled dogs

Background

Sled dogs performing endurance races have been reported to have a high incidence of gastric erosions or ulcerations and an increased risk of gastro intestinal bleeding leading to death in some cases. In addition, these dogs also become hypothyroid during training and exercise. Canine hypothyroidism has been shown to correlate with decreased von Willebrand factor antigen and potentially increased bleeding tendency. Whether increased gastro intestinal bleeding risk is exacerbated due to changes in the hemostatic balance is unknown. The aim of this study was to investigate the hemostatic balance in sled dogs before and after exercise and in addition evaluate any correlation to thyroid status. Twenty sled dogs have been assessed in untrained and trained condition and immediately after exercise. The first sample was collected in the autumn following a resting period, and subsequently the dogs were exposed to increased intensity of training. After four months the peak of physical condition was reached and a 68 km long sled pulling exercise was performed. Samples were collected before and immediately after the exercise. Evaluated parameters were: plasma thromboelastographic (TEG) R, SP, α and MA, activated partial thromboplastin time (aPTT), prothrombin time (PT), fibrinogen, von Willebrand factor (vWf), D-dimer, platelet number, thyroid hormones, hematocrit and C-reactive protein (CRP).

Results

Exercise induced an overall hypercoagulable state characterized by significant decreases of TEG R and SP and an increase of α, increased concentrations of plasma vWf and decreased aPTT. In addition, a proinflammatory status was seen by a significant increase of serum CRP concentrations. Thyroid status was confirmed to be hypothyroid as training and exercise induced significant decrease of thyroxin (T4), free thyroxin (fT4) and thyroxin stimulating hormone (TSH) concentrations. Fibrinogen decreased significantly and PT increased. The training-induced changes showed correlation between T4, fT4 and aPTT and correlation between TSH and fibrinogen. Exercise-induced changes showed correlation between T4 and PT.

Conclusions

Exercise was associated with a hypercoagulable state and an increase of vWf concentration in this group of sled dogs. Decreased thyroid hormone concentrations after training and exercise were confirmed, but were associated with increased and not decreased vWf in this group of sled dogs.

Effect of simulated deployment patrols on gastric mucosa of explosive detection dogs

Exercise-induced gastric disease is well-recognised in dogs performing ultra-endurance racing, but has not been described in dogs performing non-competitive athletic activities. Explosive detection dogs often perform prolonged periods of exercise and are reported to have chronic inappetance and weight-loss consistent with gastric disease. Seven privately-owned Labrador Retrievers trained for off-leash explosive detection activities were used to test the hypothesis that explosive detection dogs develop exercise-induced gastric disease while performing routine duties. Gastroscopy was performed on dogs before and after a 5-day exercise challenge designed to simulate routine military deployment activities. Five days of sustained submaximal exercise resulted in substantial gastric disease. These results demonstrate that dogs performing prolonged submaximal exercise consistent with off-leash explosive detection patrols are susceptible to exercise-induced gastric disease. Exercise-induced gastric disease may explain the anecdotal reports of poor thrift in these types of dogs during military deployment, and prophylactic acid suppression therapy should be considered in dogs participating in these activities.

Emergency visits and occupational hazards in German Shepherd police dogs (2008-2010)

OBJECTIVE

To describe the most common reasons for emergency medical visits in working police dogs.

DESIGN

Retrospective case control study.

ANIMALS

Two hundred three German Shepherd dogs (GSDs); 138 police dog visits by 74 dogs and 138 pet (control) dog visits by 129 dogs.

PROCEDURES

Medical records of all GSDs seen in the emergency service (ES) at the University of Pennsylvania Veterinary Hospital from July 2008 to July 2010 were reviewed. The recorded diagnoses from police GSD ES visits (defined as a new problem or new episode of a recurrent problem) were compared to those of randomly chosen pet GSD ES visits.

RESULTS

There were significantly more intact male police GSDs than pet GSDs. Police GSDs were significantly younger than pet GSDs. The most common presenting complaint in both groups was gastrointestinal disease (eg, vomiting, diarrhea, gastric dilatation and volvulus). Pet GSDs were significantly more likely to present for geriatric conditions (eg, central nervous system disease, cardiovascular disease, and neoplastic conditions). Orthopedic issues were significantly more common in police GSDs.

CONCLUSIONS AND CLINICAL RELEVANCE

Police GSDs are more likely to present for orthopedic injuries and less likely to present for geriatric diseases. Gastrointestinal disease is not unique to the working GSD and was equally represented in both populations. Preventative measures for all GSDs should focus on minimizing gastrointestinal disease. Preventive strategies focusing on physical fitness and conditioning as well as selective breeding programs may help reduce orthopedic injuries in police GSDs.

A review of stress-related mucosal disease

OBJECTIVE

To review and summarize the human and veterinary literature regarding stress-related mucosal disease (SRMD) pathogenesis, patient risk factors, and therapeutic options for prophylaxis and treatment.

ETIOLOGY

SRMD is a common sequela of critical illness in human patients. Development of SRMD results from splanchnic hypoperfusion, reperfusion injury, and exposure of the gastric mucosa to acid, pepsin, and bile acids following breakdown of the gastric mucosal defense system. Human patients with the highest risk of stress ulceration include those with respiratory failure necessitating mechanical ventilation greater than 48 h or coagulopathy. Currently, little is known about the incidence and pathophysiology of SRMD in critically ill veterinary patients.

DIAGNOSIS

A presumptive diagnosis can be made in high-risk patient populations following detection of occult or gross blood in nasogastric tube aspirates, hematemesis, or melena. Definitive diagnosis is achieved via esophagogastroduodenoscopy. Lesions are localized to the acid-producing portions of the stomach, the fundus, and body.

THERAPY

Therapy is aimed at optimization of tissue perfusion and oxygenation. Pharmacologic interventions are instituted to increase intraluminal pH and augment natural gastric defenses. Histamine(2)-receptor antagonists, proton pump inhibitors, and sucralfate are the mainstays of therapy. In people, clinically significant bleeding may necessitate additional interventions (eg, packed red blood cell transfusions, endoscopic, or surgical hemostasis).

PROGNOSIS

Mortality is increased in people with clinically significant bleeding compared to those patients who do not bleed. Institution of prophylaxis is recommended in high-risk patients. However, no consensus exists regarding initiation of prophylaxis, preference of frontline drug class, or indication for discontinuation of therapy. The prognosis of veterinary patients with SRMD remains unknown at this time.

Influence of endurance exercise on serum concentrations of iron and acute phase proteins in racing sled dogs

OBJECTIVE

To determine effects of long-distance racing exercise on iron status in endurance racing sled dogs, with or without anemia.

DESIGN

Prospective cohort study.

ANIMALS

114 dogs that participated in the 2007 Iditarod Trail Sled Dog Race (59 and 55 dogs that did or did not complete the race, respectively).

PROCEDURES

Stored serum samples obtained from 85 endurance-racing sled dogs that were expected to participate in the race were used to establish study reference intervals and prerace group values for iron-related variables. Blood samples collected from 114 study dogs before (ie, baseline) and after participation in the race were used to determine PCV and serum total protein concentrations before and after racing and assess iron-related variables after racing.

RESULTS

Mean values for PCV and serum total protein concentration were decreased after racing, compared with baseline values in the same dogs. Mean serum iron concentration was low, and mean serum ceruloplasmin and C-reactive protein (CRP) concentrations were high in dogs after racing, compared with prerace group values. Mean serum ferritin concentration was high in dogs that did not complete the race, compared with the prerace group value and that of dogs that finished the race; 4 of 113 (3.5%) study dogs had low ferritin concentrations (< 73 ng/mL) after racing, suggestive of possible iron deficiency.

CONCLUSIONS AND CLINICAL RELEVANCE

Decreased PCV and serum total protein concentrations were consistently detected, whereas iron deficiency appeared to be uncommon, in study dogs after race participation. High serum concentrations of ceruloplasmin and CRP after racing suggested that changes indicative of iron deficiency may be masked by inflammation. Alternatively, changes in serum iron and CRP concentrations may reflect a physiologic response.

Prevalence of diarrhea and enteropathogens in racing sled dogs

BACKGROUND

Diarrhea is highly prevalent in racing sled dogs, although the underlying causes are poorly understood.

HYPOTHESIS

Clostridium perfringens enterotoxin (CPE) and Clostridium difficile Toxin A and B are associated with diarrhea in racing sled dogs.

ANIMALS

One hundred and thirty-five sled dogs.

METHODS

Freshly voided feces were obtained from 55 dogs before racing and from 80 dogs after 400 miles of racing. Samples were visually scored for diarrhea, mucus, blood, and melena. CPE and C. difficile Toxin A and B were detected by ELISA. Samples were cultured for C. perfringens, C. difficile, Campylobacter, Salmonella, and Escherichia coli O157; Giardia and Cryptosporidium spp. were detected via immunofluorescence.

RESULTS

Diarrhea occurred in 36% of dogs during racing, and hematochezia, fecal mucus or melena, or all 3 occurred in 57.5% of dogs. Salmonella was isolated from 78.2% of dogs before racing, and from 71.3% of dogs during racing. C. perfringens and C. difficile were isolated from 100 and 58.2% of dogs before racing, and from 95 and 36.3% of dogs during racing. Dogs were more likely to test positive for CPE during than before racing (18.8 versus 5.5%, P = .021); however, no enteropathogens or their respective toxins were significantly associated with hematochezia or diarrhea.

CONCLUSIONS AND CLINICAL IMPORTANCE

Sled dogs participating in long distance racing have a high prevalence of diarrhea and hematochezia that is not associated with common enteropathogens. It is possible that diarrhea and hematochezia represent the effect of prolonged exercise on the gastrointestinal tract.

Effects of training and strenuous exercise on hematologic values and peripheral blood leukocyte subsets in racing sled dogs

OBJECTIVE

To determine the effects of training and sustained submaximal exercise on hematologic values in racing sled dogs.

DESIGN

Cohort study.

ANIMALS

39 Alaskan sled dogs bred for endurance racing. Procedures-Blood samples were collected prior to initiation of a 7-month training regimen (n=39), after completion of the training regimen (19), and after completion of an 1,100-mile race (9), and a CBC, differential cell count, and flow cytometry for leukocyte surface antigens were performed.

RESULTS

Both training and exercise caused significant decreases in PCV and hemoglobin concentration and significant increases in total WBC count. In contrast, training and exercise were not found to have significant effects on absolute numbers or fractions of CD4+ or CD8+ lymphocytes, other than a significant increase in the fraction of CD8+ lymphocytes associated with training.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested that training and exercise induced changes in several hematologic values in racing sled dogs. Extracellular fluid volume expansion was the likely explanation for the training-induced decrease in PCV, and acute blood loss secondary to gastrointestinal tract bleeding was likely responsible for the decrease in PCV associated with acute exercise.

Exercise stress, intestinal permeability and gastric ulceration in racing Alaskan sled dogs

Sustained strenuous exercise has been shown to produce gastrointestinal disease in athletic species, but the causative factors remain unknown. Since exercise results in oxidative stress and hypercortisolaemia, we tested the hypothesis that oxidative and physiological stress cause gastrointestinal disease in racing Alaskan sled dogs. Dogs from three racing teams were examined before (pre) and immediately after (post) completing a 1770-km sled dog race in approximately 11 days. Serum cortisol and isoprostane concentrations were compared with markers of gastrointestinal barrier integrity and endoscopic evidence of gastric ulceration. Gastric barrier integrity was assessed by measuring the urinary recovery of sucrose and intestinal barrier integrity was assessed using the urinary recovery ratio of lactulose to rhamnose (L/R), administered together by orogastric gavage. Exercise produced a significant increase in median serum cortisol (pre: 1040, 717–2946 pg ml−1 (range); post: 8072, 2228–29 571 pg ml−1; P<0.0001) and L/R recovery ratio (pre: 0.110, 0.060–0.270; post: 0.165, 0.080–0.240; P=0.009) but not isoprostane (pre: 1007, 656–2305 pg ml−1; post: 1164, 23–4710 pg ml−1; P=0.194) concentration. The increased serum cortisol concentration was not correlated with a change in L/R recovery ratio or urine sucrose concentration. Dogs with abnormal gastric endoscopy results (61% of finishers) had higher serum cortisol concentrations than dogs with normal endoscopy results (P=0.0007). We have demonstrated concurrent hypercortisolaemia and gastrointestinal barrier dysfunction with no correlation of the two. Thus, our data do not provide support for the hypothesis that increased serum cortisol concentration causes exercise-induced gastrointestinal disease.

Effect of short-term sequential administration of nonsteroidal anti-inflammatory drugs on the stomach and proximal portion of the duodenum in healthy dogs

OBJECTIVE

To evaluate effects of injection with a nonsteroidal anti-inflammatory drug (NSAID) followed by oral administration of an NSAID on the gastrointestinal tract (GIT) of healthy dogs.

ANIMALS

6 healthy Walker Hounds.

PROCEDURES

In a randomized, crossover design, dogs were administered 4 treatments consisting of an SC injection of an NSAID or control solution (day 0), followed by oral administration of an NSAID or inert substance for 4 days (days 1 through 4). Treatment regimens included carprofen (4 mg/kg) followed by inert substance; saline (0.9% NaCl) solution followed by deracoxib (4 mg/kg); carprofen (4 mg/kg) followed by carprofen (4 mg/kg); and carprofen (4 mg/kg) followed by deracoxib (4 mg/kg). Hematologic, serum biochemical, and fecal evaluations were conducted weekly, and clinical scores were obtained daily. Endoscopy of the GIT was performed before and on days 1, 2, and 5 for each treatment. Lesions were scored by use of a 6-point scale.

RESULTS

No significant differences existed for clinical data, clinicopathologic data, or lesion scores in the esophagus, cardia, or duodenum. For the gastric fundus, antrum, and lesser curvature, an effect of time was observed for all treatments, with lesions worsening from before to day 2 of treatments but improving by day 5.

CONCLUSIONS AND CLINICAL RELEVANCE

Sequential administration of NSAIDs in this experiment did not result in clinically important gastroduodenal ulcers. A larger study to investigate the effect of sequential administration of NSAIDs for longer durations and in dogs with signs of acute and chronic pain is essential to substantiate these findings.