Objective-To evaluate the antinociceptive and sedative effects and duration of action of hydromorphone hydrochloride after IM administration to American kestrels (Falco sparverius). Animals-11 healthy 2-year-old American kestrels. Procedures-Hydromorphone (0.1, 0.3, and 0.6 mg/kg) and an equivalent volume of saline (0.9% NaCl) solution (control treatment) were administered IM to kestrels in a masked randomized complete crossover study design. Foot withdrawal response to a thermal stimulus was determined 30 to 60 minutes before (baseline) and 0.5, 1.5, 3, and 6 hours after treatment administration. Agitation-sedation scores were determined 3 to 5 minutes before each thermal test. Results-Hydromorphone at 0.6 mg/kg, IM, significantly increased the thermal foot withdrawal threshold, compared with the response after administration of saline solution, for up to 3 hours, and hydromorphone at 0.1, 0.3, and 0.6 mg/kg, IM, significantly increased withdrawal responses for up to 6 hours, compared with baseline values. No significant differences in mean sedation-agitation scores were detected between hydromorphone and saline solution treatments; however, appreciable sedation was detected in 4 birds when administered 0.6 mg of hydromorphone/kg. Conclusions and Clinical Relevance-Hydromorphone at the doses evaluated significantly increased the thermal nociception threshold for American kestrels for 3 to 6 hours. Additional studies with other types of stimulation, formulations, dosages, routes of administration, and testing times are needed to fully evaluate the analgesic and adverse effects of hydromorphone in kestrels and other avian species and the use of hydromorphone in clinical settings.

Objective-To assess the effects of ketamine hydrochloride, propofol, or compounded thiopental sodium administration on intraocular pressure (IOP) and qualities of induction of and recovery from anesthesia in horses. Animals-6 healthy adult horses. Procedures-Horses were sedated with xylazine hydrochloride (0.5 mg/kg), and anesthesia was induced with guaifenesin followed by ketamine (2 mg/kg), propofol (3 mg/kg), or thiopental (4 mg/kg) in a crossover study with ≥ 1 week between treatments. For each horse, IOP in the right eye was measured with a handheld applanation tonometer before and after xylazine administration, at the time of recumbency, and every 3 minutes after induction of anesthesia until spontaneous movement was observed. Cardiorespiratory responses and venous blood measurements were recorded during anesthesia. Induction of and recovery from anesthesia were subjectively evaluated by investigators who were unaware of the anesthetic treatment of each horse. Data were analyzed via a repeated-measures ANOVA with Holm-Ŝidák post hoc comparisons. Results-Compared with findings after xylazine administration (mean +/- SD, 17 +/- 3 mm Hg), thiopental decreased IOP by 4 +/- 23%, whereas propofol and ketamine increased IOP by 8 +/- 11% and 37 +/- 16%, respectively. Compared with the effects of ketamine, propofol and thiopental resulted in significantly lower IOP at the time of recumbency and higher heart rates at 3 minutes after induction of anesthesia. No other significant differences among treatments were found. Conclusions and Clinical Relevance-These findings support the use of thiopental or propofol in preference to ketamine for horses in which increases in IOP should be minimized.

Objective-To evaluate the platelet activation response before and after treatment with clopidogrel in horses. Animals-12 healthy adult mares. Procedures-In a masked study, horses (6/group) were randomly allocated to alternately receive placebo or clopidogrel via nasogastric tube at a loading dose of 4 mg/kg followed by 2 mg/kg every 24 hours. Blood samples were collected before and 72 hours after initiation of treatment for ADP- and collagen-induced light transmission aggregometry; determination of closure time in collagen-ADP cartridges; modified thrombelastography for comparison of maximal amplitudes generated by kaolin, reptilase, and reptilase plus ADP activation; and flow cytometric tests to detect platelet fibrinogen binding, P-selectin expression, and phosphatidylserine externalization before and after ex vivo stimulation with thrombin, convulxin, thrombin with convulxin, and calcium ionophore. Results-Clopidogrel administration induced a significant decrease in mean aggregation response to 5μM and 10μM ADP stimulation; however, 2 horses had resistance to clopidogrel's inhibitory action. Significant differences after clopidogrel treatment were not found in any other tests of platelet function. Conclusions and Clinical Relevance-Assays using commercially available reagents were configured to measure different variables of the platelet activation response; however, clopidogrel's platelet inhibitory action was only detected by ADP-induced light transmission aggregometry. Results also suggested that horses, like humans, have interindividual variability in response to clopidogrel that may influence the drug's clinical efficacy as an antiplatelet agent.

Objective: To evaluate fecal calprotectin concentrations in healthy dogs and dogs with chronic diarrhea, to identify cutoff values for fecal calprotectin concentrations for use in differentiating dogs with chronic diarrhea and a canine chronic enteropathy clinical activity index (CCECAI) < 12 from dogs with chronic diarrhea and a CCECAI ≥ 12, and to evaluate the association between histologic evidence of intestinal mucosal changes and fecal calprotectin concentrations in dogs with chronic diarrhea. Sample: Fecal samples from 96 adult dogs (27 dogs with chronic diarrhea and 69 healthy control dogs). Procedures: Severity of clinical signs was evaluated on the basis of the CCECAI scoring system. Endoscopy was performed in all dogs with chronic diarrhea, and mucosal biopsy specimens were evaluated histologically. Fecal calprotectin concentration was quantified via radioimmunoassay. Results: Fecal calprotectin concentrations were significantly higher in dogs with chronic diarrhea than in healthy control dogs. Fecal calprotectin concentrations were also significantly higher in dogs with a CCECAI ≥ 12, compared with concentrations for dogs with a CCECAI between 4 and 11. Fecal calprotectin concentrations were significantly higher in dogs with chronic diarrhea associated with histologic lesions, compared with concentrations in control dogs, and were significantly correlated with the severity of histologic intestinal lesions. Among dogs with chronic diarrhea, the best cutoff fecal calprotectin concentration for predicting a CCECAI ≥ 12 was 48.9 μg/g (sensitivity, 53.3%; specificity, 91.7%). Conclusions and Clinical Relevance: Fecal calprotectin may be a useful biomarker in dogs with chronic diarrhea, especially dogs with histologic lesions.

Hemorrhagic pneumonia is an acute and fatal disease of farmed mink caused by Pseudomonas aeruginosa. The pathogenesis of this disease has not yet been resolved. Mink are the only animals known to be susceptible to acute, contagious, and fatal lung infections caused by P. aeruginosa. The purpose of this study was to investigate the correlation between dose-response and season of infection and to clarify whether Danish mink are carriers of P. aeruginosa on their nasal mucosa during the season for hemorrhagic pneumonia. To elucidate the pathogenesis of the disease, an infectious dose-response trial was carried out on adult mink and mink kits, both in the season for hemorrhagic pneumonia (November) as well as out of season (July). It proved difficult to infect mink via the intra-nasal route. Only 4 out of 60 infected mink developed clinical disease and were euthanized, all of them in November, illustrating that predisposing factors in the mink itself and not infectious dose might be crucial for disease development. We were able to culture P. aeruginosa from the nasal cavity of the clinically healthy experimental mink 8 d after inoculation. This indicated that the mink can carry P. aeruginosa on their nasal mucosa without developing the disease. It was not possible, however, to culture P. aeruginosa from the nasal cavity of clinically healthy mink obtained from farms in November, which indicates that the organism is not a normal part of the nasal mucosal flora of mink.

Objective-To measure concentrations of glutamate, aspartate, γ-aminobutyric acid (GABA), and glycine in CSF of dogs with experimentally induced subarachnoid hemorrhage (SAH) and to assess effects of cyclosporine and simvastatin on these concentrations. Sample-CSF samples from 13 dogs. Procedures-In a previous study, SAH was induced in dogs via 2 injections of autologous blood into the cerebellomedullary cistern 24 hours apart. Dogs were untreated (control; n = 5) or received simvastatin alone (4) or simvastatin in combination with cyclosporine (4). Samples of CSF were collected before the first blood injection (baseline; time 0), before the second blood injection, and on days 3, 7, and 10. For the study reported here, neurotransmitter concentrations in CSF were analyzed via high-performance liquid chromatography. Data were analyzed with a repeated-measures model with adjustments for multiple comparisons by use of the Tukey method. Results-In control dogs, the glutamate concentration peaked on day 3 and there was a significant increase in GABA and glutamate concentrations. Glutamate concentrations were significantly lower and glycine concentrations significantly higher on day 3 after administration of simvastatin alone or simvastatin in combination with cyclosporine, compared with concentrations for the control group. No significant differences in GABA and aspartate concentrations were detected among treatment groups at any time point. Conclusions and Clinical Relevance-Glutamate concentrations were increased in the CSF of dogs with SAH. Simvastatin administration attenuated high glutamate concentrations. A combination of immunosuppression and upregulation of nitric oxide synthase may be useful in lowering high glutamate concentrations in ischemic CNS conditions.

Objective-To determine the effects of 2 weeks of intense exercise on expression of markers of pulmonary venous remodeling in the caudodorsal and cranioventral regions of the lungs of horses. Animals-6 horses. Procedures-Tissue samples of the caudodorsal and cranioventral regions of lungs were obtained before and after conditioning and 2 weeks of intense exercise. Pulmonary veins were isolated, and a quantitative real-time PCR assay was used to determine mRNA expression of matrix metalloproteinase-2 and −9, tissue inhibitor of metalloproteinase-1 and −2, collagen type I, tenascin-C, endothelin-1, platelet-derived growth factor, transforming growth factor (TGF)-β, and vascular endothelial growth factor (VEGF). Protein expression of collagen (via morphometric analysis) and tenascin-C, TGF-β, and VEGF (via immunohistochemistry) was determined. Results-Exercise-induced pulmonary hemorrhage was detected in 2 horses after exercise. The mRNA expression of matrix metalloproteinase-2 and −9, tissue inhibitor of metalloproteinase-2, TGF-β, and VEGF was significantly lower in pulmonary veins obtained after exercise versus those obtained before exercise for both the caudodorsal and cranioventral regions of the lungs. Collagen content was significantly higher in tissue samples obtained from the caudodorsal regions of the lungs versus content in samples obtained from the cranioventral regions of the lungs both before and after exercise. Exercise did not alter protein expression of tenascin-C, TGF-β, or VEGF. Conclusions and Clinical Relevance-Results of this study indicated 2 weeks of intense exercise did not alter expression of marker genes in a manner expected to favor venous remodeling. Pulmonary venous remodeling is complex, and > 2 weeks of intense exercise may be required to induce such remodeling.

Objective-To compare the diagnostic quality of bronchoalveolar lavage (BAL) fluid acquired from healthy dogs by manual aspiration via polyethylene tubing (MAPT) and via suction pump aspiration (SPA) with a suction trap connection. Animals-12 healthy adult Beagles. Procedures-BAL was performed with bronchoscopic guidance in anesthetized dogs. The MAPT was performed with a 35-mL syringe attached to polyethylene tubing wedged in a bronchus via the bronchoscope's biopsy channel. The SPA was performed with 5 kPa of negative pressure applied to the bronchoscope's suction valve via a suction trap. The MAPT and SPA techniques were performed in randomized order on opposite caudal lung lobes of each dog. Two 1 mL/kg lavages were performed per site. Samples of BAL fluid were analyzed on the basis of a semiquantitative quality scale, percentage of retrieved fluid, and total nucleated and differential cell counts. Results were compared with Wilcoxon signed rank tests. Results-Percentage of BAL fluid retrieved (median difference, 16.2%), surfactant score (median difference, 1), and neutrophil count (median difference, 74 cells/μL) were significantly higher for SPA than for MAPT. A higher BAL fluid epithelial cell score was obtained via MAPT, compared with that for samples obtained via SPA (median difference, 1). Conclusions and Clinical Relevance-Results indicated that in healthy dogs, SPA provided a higher percentage of BAL fluid retrieval than did MAPT. The SPA technique may improve the rate of diagnostic success for BAL in dogs, compared with that for MAPT. Further evaluation of these aspiration techniques in dogs with respiratory tract disease is required.

Blood samples from 105 northern pintails (Anas acuta) captured on Hokkaido, Japan were tested for antibodies to avian influenza virus (AIV), Japanese encephalitis virus (JEV), and West Nile virus (WNV) to assess possible involvement of this species in the spread of economically important and potentially zoonotic pathogens. Antibodies to AIV were detected in 64 of 105 samples (61%). Of the 64 positives, 95% and 81% inhibited agglutination of two different H5 AIV antigens (H5N1 and H5N9), respectively. Antibodies to JEV and WNV were detected in five (5%) and none of the samples, respectively. Results provide evidence for prior exposure of migrating northern pintails to H5 AIV which could have implications for viral shedding and disease occurrence. Results also provide evidence for limited involvement of this species in the transmission and spread of flaviviruses during spring migration.

Objective-To assess pharmacokinetics of pregabalin in horses after a single intragastric or IV dose. Animals-5 healthy adult mares. Procedures-Horses received 1 dose of pregabalin (approx 4 mg/kg) via nasogastric tube in a crossover-design study; after a 3-week washout period, the same dose was administered IV. Food was not withheld. Plasma pregabalin concentrations in samples obtained 0 to 36 hours after administration were measured by use of ultra-performance liquid chromatography with triple quadrupole tandem mass spectrometry. Pharmacokinetic variables were estimated by means of noncompartmental analysis. Results-Mild sedation was observed in 2 horses following intragastric and IV pregabalin administration. Signs of mild, transient colic or behavioral abnormalities were observed in all horses following IV administration. After intragastric administration, median (range) maximal plasma concentration was 5.0 μg/mL (4.4 to 6.7 μg/mL), time to maximal plasma concentration was 1. 0 hour (0.5 to 2.0 hours), elimination half-life was 8.0 hours (6.2 to 9.4 hours), and area under the curve from time 0 to infinity (AUC(0-∞)) was 47.2 μg·h/mL (36.4 to 58.4 μg·h/mL). After IV administration, initial concentration was 22.2 μg/mL (19.8 to 27.7 μg/mL), elimination half-life was 7.74 hours (6.94 to 8.17 hours), and AUC0-∞ was 48.3 μg·h/mL (44.8 to 57.2 μg·h/mL). Bioavailability was 97.7% (80.7% to 109.8%). Median predicted values for minimal, mean, and maximal steady-state plasma concentrations after intragastric administration assuming an 8-hour dosing interval were 3.9, 5.3, and 6.3 μg/mL, respectively. Conclusions and Clinical Relevance-At a simulated intragastric dosage of approximately 4 mg/kg every 8 hours, median pregabalin steady-state plasma concentration in healthy horses was within the therapeutic range reported for humans. Therapeutic concentrations and safety of this dosage have not been established in horses.