bluuebunny/crossref_metadata_2025 huggingface dataset:
Third‐Degree Atrioventricular Block in 21 Cats (1997–2004)
Authors: Kellum H.B. , Stepien R.L.
Published: March 2010

The effect of 3rd‐degree atrioventricular block on long‐term outcome in cats is unknown. Clinical findings and long‐term outcome of 21 cats with 3rd‐degree atrioventricular block were studied retrospectively. Median age of cats studied was 14 years (range 7–19 years). Presenting signs included respiratory distress or collapse, but 6 cats had no clinical signs of disease. Eight cats had congestive heart failure (CHF) at the time that 3rd‐degree atrioventricular block was detected. Heart rates ranged from 80 to 140 beats per minute (bpm; median 120 bpm) with no difference in heart rate between cats with and those without CHF. Eleven of 18 cats that had echocardiograms had structural cardiac disease, and 6 cats had cardiac changes consistent with concurrent systemic disease. No atrioventricular nodal lesions were detected by echocardiography. One cat had atrioventricular nodal lesions detected on histologic examination. Median survival of 14 cats that died or were euthanized was 386 days (range 1–2,013 days). Survival did not differ between cats with or without CHF or between cats with or without structural cardiac disease. Thirteen cats with 3rd‐degree atrioventricular block survived >1 year after diagnosis, regardless of presenting signs or underlying cardiac disease. Third‐degree heart block in cats is often not immediately life threatening. Survival was not affected by the presence of underlying heart disease or congestive heart failure at the time of presentation. Even cats with collapse might survive >1 year without pacemaker implantation.
Assessment of Left Atrial Appendage Flow Velocity and its Relation to Spontaneous Echocardiographic Contrast in 89 Cats with Myocardial Disease
Authors: Schober Karsten E. , Maerz Imke
Published: March 2010

The hypotheses of this prospective study were that (1) left atrial appendage (LAA) blood flow velocities can be recorded in cats with myocardial disease by transthoracic Doppler echocardiography, (2) LA enlargement, LA mechanical dysfunction, and left ventricular (LV) diastolic abnormalities are associated with decreased LAA flow velocities, and (3) low LAA flow velocities predict the appearance of spontaneous echocardiographic contrast in cats with cardiomyopathy. Transthoracic 2‐dimensional, M‐mode, and Doppler echocardiographic studies were performed in 89 cats with hypertrophic, restrictive, dilated, or unclassified cardiomyopathy or with hyperthyroid heart disease. Maximal LAA flow velocity (LAAmax) was decreased (P< .001) in cats with cardiomyopathy (median, 0.28 m/s; range, 0.08‐1.35) compared to normal cats. Associated with decreased LAA flow velocities were increased LA size, decreased LA function, increased severity of LV diastolic dysfunction, and the presence of congestive heart failure. Multivariate logistic regression analysis detected an LAAmax<0.20 m/s as the only independent variable to predict LA spontaneous echocardiographic contrast (odds ratio, 30.1; 95% confidence interval [CI], 4.1–222.3;P< .001). Receiver operating characteristic analysis performed to predict spontaneous echocardiographic contrast indicated an area under the curve of 0.88 (95% CI, 0.80‐0.95;P< .001) with sensitivities of 100 and 74% and specificities of 69 and 83% for LAAmax<0.25 and <0.20 m/s, respectively. Thus, low LAA flow velocities identified a subgroup of patients at increased risk of spontaneous echocardiographic contrast and possible thromboembolism. These findings may have important clinical implications for anticoagulation therapy and prognostication in cats with cardiomyopathy.
CCNU in the Treatment of Canine Epitheliotropic Lymphoma
Authors: Williams Laurel E. , Rassnick Kenneth M. , Power Helen T. , Lana Susan E. , Morrison‐Collister Kirsten E. , Hansen K. , Johnson Jeffrey L.
Published: March 2010

This retrospective study examined the use of CCNU (1‐[2‐chloroethyl]3‐cyclohexyl‐1‐nitrosurea) in 36 dogs with epitheliotropic lymphoma. Thirty‐one (86%) dogs had the cutaneous form of disease, and 5 (14%) dogs had the oral form of disease. Nineteen (51%) dogs were treated with other chemotherapeutic agents before receiving CCNU. All dogs had detectable disease at the time CCNU therapy was initiated. Dogs received a median starting CCNU dosage of 70 mg/m2(range, 50–100 mg/m2). The median number of treatments administered was 3 (range, 1–12 treatments). After the initial treatment, the CCNU dosage was adjusted in 9 of 26 (35%) dogs in which CCNU was continued: 7 had dosage reductions, and 2 had dosage escalations. Twenty‐eight of 36 (78%) dogs had a measurable response to CCNU for a median duration of 106 days (95% confidence interval [CI], 75–182). Six dogs (17%) had a complete response, including 5 dogs with the cutaneous form and 1 dog with the oral form. Twenty‐two dogs (61%) had a partial response, including 20 dogs with the cutaneous form and 2 dogs with the oral form, for a median duration of 88 days (95% CI, 62–170). Toxicoses after CCNU chemotherapy included myelosuppression in up to 29% of the dogs, gastrointestinal signs in up to 22% of the dogs, and liver enzyme activity increases in up to 86% of the dogs. This study demonstrates that CCNU chemotherapy can be considered a reasonable option for the treatment of canine epitheliotropic lymphoma in dogs.
Canine Mast Cell Tumors: Correlation of Apoptosis and Proliferation Markers with Prognosis
Authors: Scase Timothy J. , Edwards David , Miller Jodi , Henley William , Smith Ken , Blunden Anthony , Murphy Sue
Published: March 2010

The Patnaik histologic grading system is commonly used to predict the behavior of cutaneous mast cell tumors (MCTs) in dogs, but it is less useful for grade 2 MCTs because they exhibit considerable variation in biological behavior. In this retrospective study, immunohistochemical staining for Ki‐67, proliferating cell nuclear antigen (PCNA), and survivin and a standardized argyrophilic staining of nucleolar organizer regions (AgNOR) protocol were performed on 121 archived paraffin‐embedded specimens of canine cutaneous MCTs, for which clinical follow‐up data were available. Cox regression models indicated that the Ki‐67 score (hazard ratio, 1.92; P <.001) and mean AgNOR score (hazard ratio, 2.57; P < .001) were significantly associated with Patnaik grade and survival time. A binary Ki‐67 variable (cutoff point Ki‐67 score = 1.8) was a significant predictor of survival for dogs with grade 2 MCTs. The estimated 1‐, 2‐, and 3‐year survival probabilities for dogs with grade 2 MCTs and Ki‐67 scores less than 1.8 were 0.92, 0.86, and 0.77, respectively (SEs, 0.08, 0.14, and 0.23, respectively; median not estimable). The corresponding survival probabilities for dogs with grade 2 MCTs and Ki‐67 scores higher than 1.8 were 0.43, 0.21, and 0.21, respectively (SEs, 0.19, 0.18, and 0.18, respectively; median survival time, 395 days). No significant association was identified between survival and survivin score or PCNA score. This study shows that both mean AgNOR score and Ki‐67 score are prognostic markers for canine MCTs. The Ki‐67 score can be used to divide Patnaik grade 2 MCTs into 2 groups with markedly different expected survival times.
The Role of Alveolar Macrophages in the Pathogenesis of Recurrent Airway Obstruction in Horses
Authors: Laan Tamarinde T.J.M. , Bull Sarah , Pirie R. , Fink‐Gremmels Johanna
Published: March 2010

When challenged with allergens and pro‐inflammatory agents, such as Aspergillus fumigatus (AF), hay dust solution (HDS) and lipopolysaccharide (LPS), the innate immune response will not only activate the immune system but also increase the amount of pro‐inflammatory cytokines in the bronchoalveolar space. The aim of this study was to assess the response of equine alveolar macrophages to different aerosolized challenges and to investigate the differences in this response between horses susceptible or nonsusceptible to recurrent airway obstruction (RAO). Seven susceptible and 5 nonsusceptible horses were challenged with saline, LPS, HDS, or AF, and bronchoalveolar lavage (BAL) cytology, total cell counts, and lung function were assessed. In addition, alveolar macrophages were isolated 6 and 24 hours after challenge, and macrophage mRNA expression of tumor necrosis factor (TNF)‐α and interleukins (IL) IL‐1β, IL‐6, IL‐8, and IL‐10 were measured by means of real‐time (RT) polymerase chain reaction (PCR). There was a significant difference in lung function, neutrophil ratios, and total cell counts in the bronchoalveolar lavage fluid between RAO‐susceptible and nonsusceptible horses. In addition, the expression of TNF‐α, IL‐1β, and IL‐8 by alveolar macrophages after challenges were higher in susceptible horses, than in nonsusceptible horses. In contrast, Il‐6, considered an anti‐inflammatory cytokine, showed a higher expression in nonsusceptible horses 6 hours after inhalation challenge with allergens and pro‐inflammatory antigens. These data suggest that the differences between susceptible and nonsusceptible horses to RAO are not only dependent on adaptive immunity but also start with an innate immune response.
Lack of Clinical Efficacy of a Phosphodiesterase‐4 Inhibitor for Treatment of Heaves in Horses
Authors: Lavoie Jean‐Pierre , Pasloske Kirby , Joubert Philippe , Cordeau Marie‐Eve , Mancini Joseph , Girard Yves , Friesen Richard W. , Frenette Richard , Blouin Marc , Young Robert N. , Hickey Gerry
Published: March 2010

Phosphodiesterase‐4 (PDE 4) enzyme inhibitors have been shown to have anti‐inflammatory properties in various animal disease processes and therefore could be effective drugs for the treatment of equine airway diseases. The purpose of this study was to evaluate the efficacy and adverse effects of the PDE 4 inhibitor L‐826,141 in horses with heaves. In a blinded parallel design, horses with heaves exposed daily to moldy hay were given a placebo for 14 days and then administered either L‐826,141 (n = 6; loading dose of 1 mg/kg IV followed by 0.5 mg/kg IV q48h) or dexamethasone (n = 6; 0.04 mg/kg IV q24h) from days 15 to 29 (study 1). Pulmonary function and bronchoalveolar (BAL) cytology were evaluated weekly from baseline (day 0) to 29 days. In study 2, horses were treated with L‐826,141 (1.0 mg/kg IV q24h) for 8 days. Although ex vivo lipopolysaccharide‐induced tumor necrosis factor (TNF)‐α and LTB4production by fresh blood were inhibited up to 90% after repeated administrations of L‐826,141, this treatment failed to improve lung function. In contrast, dexamethasone (positive control) treatment resulted in significant improvement in lung mechanics and airway function in all horses. Neither drug had a significant effect on BAL total cell counts and differential cytology. Administration of the PDE 4 inhibitor L‐826,141 for up to 14 days to horses with heaves was not associated with an improvement in airway function or inflammation. These findings suggest that the PDE 4 enzyme is not a key mediator of lung inflammation in heaves.
Successful Conversion of Equine Atrial Fibrillation Using Oral Flecainide
Authors: Risberg Åse I. , McGuirk Sheila M.
Published: March 2010

Atrial fibrillation is the most common arrhythmia affecting performance in horses. Conversion to sinus rhythm carries a good prognosis if no significant underlying cardiac disease is present and horses commonly return to performance at the previous level or above. The drug most commonly used to convert equine atrial fibrillation is quinidine. However, quinidine has the potential for a number of adverse effects including colic, nasal mucosal edema, dyspnea and laminitis. Quinidine also requires administration through a nasogastric tube, as the drug is very bitter and acidic and may cause oral ulcerations if administered PO. Flecainide is an antiarrhythmic agent of Singh‐Vaughan Williams class Ic, whereas quinidine belongs to class Ia. Intravenously administered flecainide has been reported to be a safe and effective drug for treatment of induced atrial fibrillation in the horse, with fewer adverse effects compared to quinidine, but has been less effective when administered to horses with naturally occurring atrial fibrillation. The pharmacokinetics of oral flecainide and the oral dosage required to treat equine atrial fibrillation have been determined. To the authors' knowledge, there are no reports describing treatment of equine atrial fibrillation with oral flecainide. This report describes the successful conversion of naturally occurring atrial fibrillation, by means of oral flecainide, in a horse.
Effects of Allopurinol Treatment on the Progression of Chronic Nephritis in Canine Leishmaniosis (Leishmania infantum)
Authors: Plevraki K. , Koutinas A.F. , Kaldrymidou H. , Roumpies N. , Papazoglou L.G. , Saridomichelakis M.N. , Savvas I. , Leondides L.
Published: March 2010

Forty dogs with canine leishmaniosis (CL) participated in this study, which was designed to investigate the effect of allopurinol on the progression of the renal lesions associated with this disease. The animals were allocated into 5 groups. Group A dogs (n = 12) had neither proteinuria nor renal insufficiency, group B dogs (n = 10) had asymptomatic proteinuria, and group C dogs (n = 8) were proteinuric and azotemic. Two more groups, CA and CB, comprising 5 dogs each, served as controls for groups A and B, respectively. Group A, B, and C dogs received allopurinol PO (10 mg/kg q12h) for 6 months, whereas group CA and CB dogs were placebo‐treated. Serum biochemistry profile, urinalysis, urine protein/creatinine ratio, and glomerular filtration rate (GFR) measurements were carried out at the beginning of the study, the 3rd month, and the 6th month, whereas renal biopsies were carried out only at the beginning and the end of the trial. Membranoproliferative glomerulonephritis was the most common cause of chronic renal failure. Mesangioproliferative and tubulointerstitial nephritis were detected even in group A and CA dogs. Allopurinol not only lowered proteinuria in group B dogs but also prevented the deterioration of GFR and improved the tubulointerstitial, but not the glomerular, lesions in both group A and group B dogs. Further, it resolved the azotemia in 5 of the 8 dogs admitted with 2nd stage chronic renal failure (group C). Consequently, treatment with allopurinol is advisable in CL cases with asymptomatic proteinuria or 1st‐2nd stage chronic renal failure.
Use of Glargine and Lente Insulins in Cats with Diabetes Mellitus
Authors: Weaver Kelli E. , Rozanski Elizabeth A. , Mahony Orla M. , Chan Daniel L. , Freeman Lisa M.
Published: March 2010

The goals of this study were to compare the efficacy of once‐daily administered Glargine insulin to twice‐daily administered Lente insulin in cats with diabetes mellitus and to describe the use of a high‐protein, low‐carbohydrate diet designed for the management of diabetes mellitus in cats. All cats with naturally occurring diabetes mellitus were eligible for inclusion. Baseline testing included a physical examination, serum biochemistry, urinalysis and urine culture, serum thyroxine concentration, and serum fructosamine concentration. All cats were fed the high‐protein, low‐carbohydrate diet exclusively. Cats were randomized to receive either 0.5 U/kg Lente insulin q12h or 0.5 U/kg Glargine insulin q24h. Re‐evaluations were performed on all cats at weeks 1, 2, 4, 8, and 12, and included an assessment of clinical signs, physical examination, 16‐hour blood glucose curve, and serum fructosamine concentrations. Thirteen cats completed the study (Lente, n = 7, Glargine, n = 6). There was significant improvement in serum fructosamine and glucose concentrations in all cats but there was no significant difference between the 2 insulin groups. Four of the 13 cats were in complete remission by the end of the study period (Lente, n = 3; Glargine, n = 1). The results of the study support the use of once‐daily insulin Glargine or twice‐daily Lente insulin in combination with a high‐protein, low‐carbohydrate diet for treatment of feline diabetes mellitus.
Pharmacokinetics and Clinical Efficacy of Cyclosporine Treatment of Dogs with Steroid‐Refractory Inflammatory Bowel Disease
Authors: Allenspach K. , Rüfenacht S. , Sauter S. , Gröne A. , Steffan J. , Strehlau G. , Gaschen F.
Published: March 2010

The usual treatment of dogs with inflammatory bowel disease (IBD) consists of administration of immunosuppressive doses of steroids. However, some dogs are refractory to steroid treatment and pose a significant challenge to the veterinarian. Because cyclosporine A (cyA) has been shown to be effective in steroid‐resistant IBD in humans, the purpose of this study was to investigate the pharmacokinetics and clinical efficacy of PO cyA treatment in dogs with steroid‐refractory IBD (n = 14). All dogs were treated with cyA 5 mg/kg PO q24h for a period of 10 weeks. A clinical activity score was assigned to assess severity of clinical signs before and after treatment. The total number of infiltrating lymphocytes and T cells in duodenal biopsies were assessed before and after treatment in 9 dogs. In addition, serum concentration of cyA was measured in 8 dogs over a 24‐hour period. Pharmacokinetic profiles in dogs with IBD were similar to those of healthy dogs. Improvement of clinical signs was observed in 12 of 14 dogs with IBD. Median clinical activity score after treatment with cyA was significantly reduced from a median score of 9 to a median score of 5 (P= 0.001). T cell numbers in duodenal biopsies were significantly decreased after treatment from a median plusmn; 95% range in the villous region of 28 (19–30) cells/10,000 μm2before versus 7 (0–10)/10,000 μm2after treatment,P= 0.01; and from a median ± 95% range number in the crypt region of 15 (6–23) cells/10,000 μm2before versus 4 (0–9)/10,000 μm2after treatment,P= 0.02, implying T cell lysis as a possible mechanism of action. In conclusion, based on this small study, cyA appears to be an effective alternative drug in dogs with IBD that are refractory to immunosuppressive doses of steroids.
Antibiotic Sensitivity Profiles Do Not Reliably Distinguish Relapsing or Persisting Infections from Reinfections in Cats with Chronic Renal Failure and Multiple Diagnoses of Escherichia coli Urinary Tract Infection
Authors: Freitag Thurid , Squires Richard A. , Schmid Jan , Elliott Jonathan , Rycroft Andrew N.
Published: March 2010

Older cats with chronic renal failure (CRF) commonly develop urinary tract infections (UTI). Uropathogenic Escherichia coli (UPEC) is identified as the causal agent of UTI in most affected cats. Infections are often complicated, and UPEC infections may persist or recur in these cats. Antibiotic sensitivity profiles have been used to distinguish relapsing or persisting UTI from reinfection by different clones of the same species. However, the accuracy with which antibiograms discriminate different urinary E coli clones in cats is uncertain. We studied 17 cystocentesis‐derived UPEC isolates collected from 5 cats with stable CRF and multiple diagnoses of UTI. UTIs were classified as relapses versus persistent infections or reinfections using antibiograms determined by Kirby‐Bauer discs and Etests±. Subsequently, clonality of UPEC isolates was determined by pulsed‐field gel electrophoresis (PFGE). A comparison of PFGE results with antibiograms indicated that antibiotic resistance patterns varied considerably within several individual E coli clones. Both antibiotic susceptibility tests differentiated between relapsing or persistent infections and reinfections with only 58% overall efficiency. Thus, antibiotic sensitivity profiles cannot be relied upon to distinguish between persisting or relapsing infections as compared to reinfections in cats with CRF and multiple diagnoses of E coli UTI.
Physiologic VDD versus Nonphysiologic VVI Pacing in Canine 3rd‐Degree Atrioventricular Block
Authors: Bulmer Barret J. , Sisson D. David , Oyama Mark A. , Solter Philip F. , Grimm Kurt A. , Lamont Leigh
Published: March 2010

Historically, ventricular demand, nonphysiologic (VVI) pacing has been the most commonly used modality to treat 3rd‐degree atrioventricular (AV) block. The goal of this study was to determine the feasibility of using a commercial, single‐lead, physiologic (VDD) pacemaker in dogs with 3rd‐degree AV block. Furthermore, we hoped to characterize and identify differences in the radiographic, echocardiographic, neurohormonal, and quality of life consequences of physiologic versus nonphysiologic pacing. We evaluated 10 dogs during a 12‐week crossover study. Acutely, rate‐matched physiologic pacing reduced pulmonary capillary wedge pressure by 19% compared with nonphysiologic pacing. VDD pacing significantly reduced left atrial size normalized to body weight, left atrial‐to‐aortic root ratio, and left ventricular end‐systolic dimension and increased fractional shortening, aortic Doppler velocity, cardiac output, and stroke volume compared with VVI pacing. Variable rate VDD pacing resulted in a significantly slower heart rate (HR) during echocardiography than fixed‐rate (100 bpm) VVI pacing. AV synchronous pacing reduced circulating N‐terminal proatrial natriuretic peptide (ANP), norepinephrine (NOR), and epinephrine (EPI) concentrations compared with asynchronous pacing. There were no significant differences in systemic blood pressure, thoracic radiographs, or owner‐perceived quality of life. The median percentage of AV synchronous pacing during the VDD modality was 99.8% (range, 1.2 to 99.9%). This study confirms the potential to achieve physiologic pacing with a commercial, single‐lead system in dogs. VDD pacing improved hemodynamics and neurohormonal profiles over asynchronous pacing although the long‐term clinical benefits of these changes remain to be determined.
N‐Terminal Atrial Natriuretic Peptide Immunoreactivity in Plasma of Cats with Hypertrophic Cardiomyopathy
Authors: MacLean Heidi N. , Abbott Jonathan A. , Ward Daniel L. , Huckle William R. , Sisson David D. , Pyle R. Lee
Published: March 2010

Atrial natriuretic peptide (ANP) is an important regulator of fluid homeostasis and vascular tone. We sought to compare N‐terminal ANP immunoreactivity (ANP‐IR) in plasma from cats with and without hypertrophic cardiomyopathy (HCM). Secondarily, we evaluated relationships between ANP‐IR and echocardiographical variables in cats with HCM and healthy cats. Venous blood samples were obtained from 17 cats with HCM and from 19 healthy cats. Plasma ANP‐IR concentration was determined by an enzyme‐linked immunoassay. Two cats with HCM had clinical evidence of congestive heart failure; the remainder had subclinical disease. Plasma ANP‐IR concentration was higher in cats with HCM (3,808 ± 1,406 fmol/L, mean ± SD) than in control cats (3,079 ± 1,233 fmol/L), but this difference was not statistically significant (P= .11; 95% confidence interval [CI] = ‐166 to 1,622). There was a significant, but modest correlation between plasma ANP‐IR concentration and left ventricular posterior wall thickness (r= 0.42;P= .01). Additionally, plasma ANP‐IR concentration was weakly correlated with left atrial size (r= 0.35;P= .03). A linear regression model was developed to further explore these relationships. Atrial size and wall thickness were included in the model; the 2 explanatory variables had an interactive effect on plasma ANP‐IR concentration (R2= 0.27;P= .02). There was no appreciable correlation between plasma ANP‐IR concentration and any other echocardiographical variable. In a population that included cats with subclinical disease, those with HCM did not have significantly higher plasma ANP‐IR concentration than did healthy cats. An exploratory multivariable regression analysis suggested a linear relationship between ANP‐IR concentration and atrial size, wall thickness, and their interaction.
Use of Rheolytic Thrombectomy in the Treatment of Feline Distal Aortic Thromboembolism
Authors: Reimer S. Brent , Kittleson Mark D. , Kyles Andrew E.
Published: March 2010

The purpose of this prospective clinical trial was to evaluate the safety and efficacy of a commercially available rheolytic thrombectomy system in the treatment of naturally occurring feline aortic thromboembolic disease. All 6 cats enrolled in the investigation were affected at the level of the distal aorta and had signs of the disease affecting both pelvic limbs. Cats were anesthetized and an arteriotomy was performed on 1 carotid artery to gain access to the arterial system. Selective arterial angiography was used to confirm the presence of thromboembolic disease. The thrombectomy system was advanced to the level of the thrombus using fluoroscopic guidance. Repeat angiography was used intermittently to assess progress of thromboembolus dissolution throughout the procedure. The use of the rheolytic thrombectomy system resulted in successful thrombus dissolution in 5 of 6 cats. Three of 6 cats survived to discharge. Both of these results compare favorably with conventional therapies used in the treatment of this disease. Feline distal aortic thromboembolism is a frustrating disease that warrants a guarded to poor prognosis. Rheolytic thrombectomy may provide veterinarians with an alternative therapy in the treatment of thromboembolic diseases, including feline distal aortic thromboembolism.
Pharmacodynamics of Carvedilol in Conscious, Healthy Dogs
Authors: Gordon Sonya G. , Arsenault Wendy G. , Longnecker Mike , Boothe Dawn M. , Miller Matthew W. , Chalkley Jeff
Published: March 2010

The purpose of the study reported here was to determine the magnitude and duration of beta‐blocking efficacy, determine an effective dose and dosing interval, and document safety and tolerability of carvedilol given orally in clinically normal dogs. Pharmacodynamic data were evaluated in conscious, unrestrained, healthy hound dogs at baseline and after long‐term oral administration of carvedilol (1.5 mg/kg of body weight PO q12h for >5 days). At baseline, heart rate (HR) and blood pressure (BP) data were collected continuously for 24 hours, and complete echocardiography was performed. This protocol was repeated after long‐term oral carvedilol administration. Additionally, isoproterenol was administered to evaluate the magnitude and duration of the nonselective beta‐blocking efficacy of carvedilol. An isoproterenol challenge was performed 0.75, 1.5, 2.25, 4, 6, 12, and 24 hours after carvedilol administration, with echocardiography being performed once at 2 hours. Plasma samples were obtained prior to each challenge time point for determination of plasma carvedilol concentration. Time series regression analysis indicated no difference between baseline and carvedilol‐induced HR or BP trend lines in 6 of 8 dogs. In 2 of 8 dogs, HR, after long‐term carvedilol administration, was reduced. Carvedilol attenuated isoproterenol‐induced changes in HR by 54–76% through 12 hours and by 30% at 24 hours. The BP changes were attenuated by 80–100% through 12 hours. These data suggest that carvedilol (1.5 mg/kg PO q12h) in healthy, conscious dogs confers nonselective beta blockade for 12 hours, with minimal effects on resting HR, BP, and echocardiographic variables. Additionally, the magnitude of beta blockade correlated strongly to peak plasma carvedilol concentration, suggesting that therapeutic drug monitoring may be clinically useful.
Clinical and Topographic Magnetic Resonance Characteristics of Suspected Brain Infarction in 40 Dogs
Authors: Garosi L. , McConnell J.F. , Platt S.R. , Barone G. , Baron J.C. , de Lahunta A. , Schatzberg S.J.
Published: March 2010

Medical records of 40 dogs presented for evaluation of acute‐onset, nonprogressive, intracranial dysfunction by means of magnetic resonance imaging (MRI) diagnosis of brain infarction were reviewed. Location of the brain infarcts was: 11 of 38, telencephalic; 8 of 38, thalamic/midbrain; 18 of 38, cerebellar; and 3 of 38, multifocal. Telencephalic infarcts developed within the territory of the middle cerebral (4/11), rostral cerebral (2/11), and striate (5/11) arteries. Thalamic/midbrain infarcts developed within the territory of perforating arteries of the caudal portion of the thalamus and rostral portion of the brainstem (8/8). All cerebellar infarcts (18/38) were within the territory of the rostral cerebellar artery or one of its branches. All infarcts appeared nonhemorrhagic, with marked contrast enhancement observed in only 3 of 38 dogs, all of which were imaged more than 7 days after the onset of signs of neurologic dysfunction. Diffusion‐weighted imaging (DWI) sequences were available from 6 dogs, all imaged within 5 days of the onset of signs of neurologic dysfunction. Suspected infarcts were hyperintense on DWI sequences and were hypointense on the apparent diffusion coefficient map. Telencephalic infarcts caused abnormal mental status, contralateral postural reaction deficit, contralateral nasal hypalgesia, contralateral menace deficit, and ipsilateral circling. Thalamic/midbrain infarcts caused contralateral or ipsilateral postural reaction deficit, contralateral menace deficit, ipsilateral head tilt or turn, nystagmus, ventrolateral strabismus, and anisocoria. Cerebellar infarcts caused ipsilateral asymmetric cerebellar quality ataxia, head tilt, intermittent opisthotonus, nystagmus, and ipsilateral menace deficit with apparent normal vision.
Development and Evaluation of aSarcocystis neurona‐Specific IgM Capture Enzyme‐Linked Immunosorbent Assay
Authors: Murphy J.E. , Marsh A.E. , Reed S.M. , Meadows C. , Bolten K. , Saville W.J.A.
Published: March 2010

Equine protozoal myeloencephalitis (EPM) is a serious neurologic disease of horses caused primarily by the protozoal parasiteSarcocystis neurona.Currently available antemortem diagnostic testing has low specificity. The hypothesis of this study was that serum and cerebrospinal fluid (CSF) of horses experimentally challenged withS neuronawould have an increasedS neurona‐specific IgM (Sn‐IgM) concentration after infection, as determined by an IgM capture enzyme linked immunoassay (ELISA). The ELISA was based on theS neuronalow molecular weight protein SNUCD‐1 antigen and the monoclonal antibody 2G5 labeled with horseradish peroxidase. The test was evaluated using serum and CSF from 12 horses experimentally infected with 1.5 millionS neuronasporocysts and 16 horses experimentally infected with varying doses (100 to 100,000) ofS neuronasporocysts, for which results of histopathologic examination of the central nervous system were available. For horses challenged with 1.5 million sporocysts, there was a significant increase in serum Sn‐IgM concentrations compared with values before infection at weeks 2–6 after inoculation (P< .0001). For horses inoculated with lower doses ofS neurona, there were significant increases in serum Sn‐IgM concentration at various points in time after inoculation, depending on the challenge dose (P< .01). In addition, there was a significant increase between the CSF Sn‐IgM concentrations before and after inoculation (P< .0001). These results support further evaluation of the assay as a diagnostic test during the acute phase of EPM.
Effects of Chemotherapy on Immune Responses in Dogs with Cancer
Authors: Walter Claudia U. , Biller Barbara J. , Lana Susan E. , Bachand Annette M. , Dow Steven W.
Published: March 2010

Chemotherapy is assumed to be immunosuppressive; yet to the authors' knowledge, the effects of common chemotherapy protocols on adaptive immune responses in dogs with cancer have not been fully evaluated. Therefore, a study was conducted to evaluate the effects of 2 common chemotherapy protocols on T‐ and B‐cell numbers and humoral immune responses to de novo vaccination in dogs with cancer. Twenty‐one dogs with cancer (12 with lymphoma, 9 with osteosarcoma) were enrolled in a prospective study to assess effects of doxorubicin versus multi‐drug chemotherapy on adaptive immunity. Numbers of circulating T and B cells were assessed by flow cytometry, and antibody responses to de novo vaccination were assessed before, during, and after chemotherapy. The T‐ and B‐cell numbers before treatment also were compared with those of healthy, age‐matched, control dogs. Prior to treatment, dogs with cancer had significantly fewer (P < .05) CD4+ T cells and CD8+ T cells than did healthy dogs. Doxorubicin treatment did not cause a significant decrease in T‐ or B‐cell numbers, whereas treatment with combination chemotherapy caused a significant and persistent decrease in B‐cell numbers. Antibody titers after vaccination were not significantly different between control and chemotherapy‐treated dogs. These findings suggest that chemotherapy may have less impact on T‐cell numbers and ability to mount antibody responses in dogs with cancer than was previously anticipated, though dogs with lymphoma or osteosarcoma appear to be relatively T‐cell deficient before initiation of chemotherapy.
Measurement of Free Thyroxine Concentration in Horses by Equilibrium Dialysis
Authors: Breuhaus Babetta A. , Refsal Kent R. , Beyerlein Susan L.
Published: March 2010

The purpose of the study reported here was to validate measurement of free thyroxine (fT4) concentration in equine serum by equilibrium dialysis (fT4D), and to compare values with fT4concentration measured directly and with total T4(TT4) concentration. The fT4D, fT74, and TT4concentrations were measured over a range of values in euthyroid horses and horses made hypothyroid by administration of propylthiouracil (PTU). Concentrations of fT4D (<1.8–83 pmol/L) were consistently higher than those of fT4(<1–40 pmol/L). There was a significant (P< .001) regression of fT4D on fT4in 503 samples from normal horses (y = 2.086x‐ 0.430). In baseline samples from 71 healthy euthyroid horses, fT4concentration ranged from 6‐ 21 pmol/L (median, 11 pmol/L; 95% confidence interval [CI]10.5–11.8 pmol/L), and fT4D concentration ranged from 7–47 pmol/L (median, 22 pmol/L; 95% CI 20.9–25.1 pmol/L). Free T4D, fT4, and TT4concentrations were also measured in 34 ill horses. Horses consuming PTU and ill horses had significantly (P< .05) lower serum concentration of TT4, fT4, and fT4D than did clinically normal, healthy horses. If serum samples from ill horses were further subdivided into samples from horses that lived and samples from horses that died, fT4D concentration was not significantly different in ill horses that lived, compared with that in healthy horses, whereas fT4concentration was still significantly decreased in ill horses that died (P< 0.001). We conclude that measurement of fT4concentration by equilibrium dialysis is a valid technique in the horse, and its use may provide improved ability to distinguish nonthyroidal illness syndrome from hypothyroidism in that species.
Comparison of Four Staining Methods for Detection of Mast Cells in Equine Bronchoalveolar Lavage Fluid
Authors: Leclere Mathilde , Desnoyers Michel , Beauchamp Guy , Lavoie Jean‐Pierre
Published: March 2010

Mast cells normally are present in equine bronchoalveolar lavage fluid (BALF), but usually represent <2% of all cells in healthy horses. An increased percentage of mast cells has been associated with airway hyperactivity and inflammatory airway diseases, but marked differences are reported between studies in normal and diseased horses. Because an abnormal mast cell count may be of clinical relevance, we compared the ability of a fast Romanowsky method to stain mast cell granules with that of 3 metachromatic stains: automated Romanowsky, May‐Grünwald Giemsa, and toluidine blue stains. The BALF cells from 24 horses were studied. A differential cell count was performed blindly on 400 cells. The percentages of mast cells obtained were analyzed by means of repeated‐measures analysis of variance and Fischer's PLSD test. The Bland and Altman method was used to assess agreement among stains. The mean percentage of mast cells in BALF was significantly lower with the fast Romanowsky than with the automated Romanowsky, May‐Grünwald Giemsa, and toluidine blue stains. With the fast Romanowsky stain, the metachromatic granules of mast cells were not stained, and their identification was based on morphologic criteria. Toluidine blue staining allowed detection of the highest mean percentage of mast cells, but was inadequate for performing a differential cell count on other cell types. In conclusion, fast Romanosky stain may be inadequate for detection of mast cells in equine BALF, whereas automated Romanowsky, May‐Grünwald Giemsa, and toluidine blue stains provide metachromatic staining of mast cell granules.
Usefulness of a Commercial Equine IgG Test and Serum Protein Concentration as Indicators of Failure of Transfer of Passive Immunity in Hospitalized Foals
Authors: Metzger Nadine , Hinchcliff Kenneth W. , Hardy Joanne , Schwarzwald Colin C. , Wittum Thomas
Published: March 2010

Detection of failure of transfer of passive immunity (FTPI) is important in reducing morbidity and mortality in neonatal foals. We investigated the performance of a commercial equine IgG test (SNAP Foal IgG Test Kit) to diagnose FTPI in hospitalized foals. Furthermore, we evaluated the usefulness of serum total protein (STP) and serum globulin (SG) concentrations as indicators of FTPI. Serum IgG concentration was measured by means of the SNAP test and single radial immunodiffusion, and SG and STP concentrations were determined by means of a clinical chemistry analyzer. Subjects were 67 hospitalized foals, 19 days old. The SNAP test was repeated on 37 samples from 29 foals, with identical results for 24 samples (kappa statistic, 0.64; 95% confidence interval [CI], 0.46–0.82). The sensitivity of the SNAP test to detect serum IgG concentration [IgG] ≥400 and ≥800 mg/dl was 90% (95% CI, 71–98%) and 95% (85–99%), respectively, and the specificity was 79% (71–82%) and 52% (39–57%), respectively. Sensitivity for detection of [IgG] ≥ 400 mg/dl was not affected (P> .05) by plasma fibrinogen concentration, sepsis score, or bacteremia. Specificity for detection of [IgG] ± 800 mg/dl was lower (P< .05) in foals with sepsis score #11 (50% [31–60%] versus 100% [8–100%]) and bacteremia (25% [5–56%] versus 62% [45–62%]). Sensitivity and specificity of [STP] ± 5.0 g/dl for [IgG] ± 800 mg/dl was 94% (83–99%) and 47% (30–56%), respectively. Performance of the SNAP test in hospitalized foals is impaired because of low specificity, but can have usefulness provided that the properties of the test and characteristics of the foal being examined are considered when interpreting the results. The STP and SG concentrations are poor sole indicators of FTPI in hospitalized foals, but may be useful adjunctive tests.
Sucrose Concentration in Blood: A New Method for Assessment of Gastric Permeability in Horses with Gastric Ulceration
Authors: Hewetson M. , Cohen N.D. , Love S. , Buddington R.K. , Holmes W. , Innocent G.T. , Roussel A.J.
Published: March 2010

A urine sucrose test has recently been reported to be a reliable method of detecting gastric ulcers in horses; however, technical difficulties associated with urine collection have limited the practical value of the test. The objective of this pilot study was to determine whether gastric sucrose permeability, as evaluated by serum sucrose concentration, could be used to detect gastric mucosal injury in horses. Twelve adult horses with naturally acquired gastric ulceration were studied. After a 20‐hour nonfeeding period, each horse was dosed with 250 g of sucrose via nasogastric intubation. Blood samples were collected at 0, 15, 30, 45, 60, and 90 minutes, and horses underwent gastroscopy 4 hours later. The severity of gastric ulceration in each horse was defined by means of a 4‐point ulcer‐scoring system, and the relationship with serum sucrose concentration was analyzed by means of a linear mixed‐effects model. Serum sucrose concentration was measured by liquid chromatography operating in tandem with electrospray mass spectrometry. After nasogastric administration of table sugar, horses with moderate to severe gastric ulceration had significant increase in serum sucrose concentration at 30, 45, 60, and 90 minutes, relative to earlier times (P< .05). Peak sucrose concentration was observed at 45 minutes, and was correlated with ulcer severity (Spearman's rank correlation coefficient = 0.898,P< .05). These data indicate that determination of sucrose concentration in equine serum may be a useful test for identifying horses with endoscopically visible gastric ulceration and has potential use as a noninvasive method for screening and monitoring horses engaged in racing training and other performance‐related disciplines.
Effect of Beclomethasone Dipropionate and Dexamethasone Isonicotinate on Lung Function, Bronchoalveolar Lavage Fluid Cytology, and Transcription Factor Expression in Airways of Horses with Recurrent Airway Obstruction
Authors: Couëtil Laurent L. , Art Tatiana , de Moffarts Brieuc , Becker Martine , Mélotte Dorothée , Jaspar Fabrice , Bureau Fabrice , Lekeux Pierre
Published: March 2010

Glucocorticoid (GC) therapy is recognized to be effective for the treatment of recurrent airway obstruction (RAO) in horses. Anti‐inflammatory properties of GC are thought to be mediated by suppression of inflammatory gene expression via inhibition of transcription factors such as nuclear factor‐±B (NF‐±B) and activator protein‐1 (AP‐1). The purpose of this study was to evaluate the effect of low‐dose inhaled beclomethasone dipropionate and injectable dexamethasone 21‐isonicotinate on clinical signs, pulmonary function, airway cytology, and activity of NF‐kB and AP‐1 in bronchial cells of RAO‐affected horses. Seven horses with RAO were exposed to moldy hay until they developed airway obstruction on 3 separate occasions. In a crossover design, they were then treated with a placebo (injection on day 1), inhaled beclomethasone (500 μg q12h for 10 days), or dexamethasone (0.06 mg/kg, IM on day 1) and monitored for 10 days. Pulmonary function, bronchoalveolar lavage fluid cytology, and NF‐kB and AP‐1 activity in bronchial brushing cells were measured before (day 1) and after treatment (day 10). Treatment with beclomethasone resulted in significantly improved pulmonary function of RAO‐affected horses compared with placebo and dexamethasone treatments. However, none of the treatments had an effect on bronchoalveolar lavage fluid cytology or NF‐kB and AP‐1 activity. These findings reveal that, in a model of severe RAO, the benefits of low‐dose inhaled beclomethasone on pulmonary function are not accompanied by a decrease in airway inflammatory cells or a suppression of transcription factors NF‐kB and AP‐1 DNA‐binding activity.
Risk of After‐Hours Visits to an In‐Hospital Food Animal Service by Species
Authors: Tyler Jeff W. , Middleton John R. , Tessman Ronald K. , Nagy Dusty W.
Published: March 2010

Computer records were accessed documenting in‐hospital accessions to the food animal service maintained by the University of Missouri, College of Veterinary Medicine between January 1, 2001 and December 6, 2004. For each species category, the prevalence and relative risk (RR) of after‐hours admission were calculated. The prevalence of after‐hours visits varied from 0.040 for swine to 0.234 for South American camelidae. Using cattle as a reference level, the relative risk for an after‐hours admission was decreased in swine (RR 5 0.51) and increased in South American camelidae (RR 5 3.04) and sheep or goats (RR 5 1.66). The likelihood of an after‐hours admission differed significantly among groups.
Hyperphosphatasemia in Scottish Terriers: 7 Cases
Authors: Gallagher AIexander E. , Panciera David L. , Panciera Roger J.
Published: March 2010

Increased serum alkaline phosphatase (ALKP) activity in dogs is commonly encountered. In the study reported here, 7 Scottish Terriers were identified with hyperphosphatasemia, for which a cause could not be determined. The clinicopathologic findings of the syndrome are described and correlated with hepatic pathologic changes in biopsy specimens and in specimens obtained at postmortem examination. Five of the 7 dogs were related. The ALKP activity ranged from 1.7 to 17 times the reference value at the time of biopsy. Increased ALKP activity was present for > 6 months in 2 dogs and > 12 months in 5 dogs; activity was > 1,000 U/L for at least 1 measurement in 5 dogs. Results of liver function testing, adrenocortical function testing, and hepatic ultrasonography were reviewed. Results of histological examination were normal in 6 dogs. One dog had regional, chronic cholangitis without evidence of cholestasis. The lesion was judged unlikely to account for the degree of hyperphosphatasemia. This study provides evidence of possible benign hyperphosphatasemia in Scottish Terriers or of another familial disorder causing asymptomatical hyperphosphatasemia without corresponding histopathological abnormalities in the liver. Prospective studies of ALKP isoenzyme characterization, investigation of skeletal integrity, evaluation of additional related dogs to determine prevalence, and longer follow‐up evaluation are necessary to better characterize this finding.
ACVIM Small Animal Consensus Statement on Lyme Disease in Dogs: Diagnosis, Treatment, and Prevention
Authors: Littman Meryl P. , Goldstein Richard E. , Labato Mary A. , Lappin Michael R. , Moore George E.
Published: March 2010

The purpose of this report is to offer a consensus opinion of ACVIM diplomates on the diagnosis, treatment, and prevention ofBorrelia burgdorferiinfections in dogs (canine Lyme disease). Clinical syndromes known to commonly be associated with canine Lyme disease include polyarthritis and glomerulopathy. Serological test results can be used to document exposure toB. burgdorferibut not prove illness. Although serum enzyme‐linked immunosorbent assay/indirect fluorescent antibody assay titers can stay positive for months to years after treatment, quantitative C6 peptide antibody paired tests need more study. Serological screening of healthy dogs is controversial because it can lead to overdiagnosis or overtreatment of normal dogs, most of which never develop Lyme disease. However, serological screening can provide seroprevalence and sentinel data and stimulate owner education about tick infections and control. Although it is unknown whether treatment of seropositive healthy dogs is beneficial, the consensus is that seropositive dogs should be evaluated for proteinuria and other coinfections and tick control prescribed. Tick control can include a product that repels or protects against tick attachment, thereby helping to prevent transmission of coinfections as well asBorreliaspp. Seropositive dogs with clinical abnormalities thought to arise from Lyme disease generally are treated with doxycycline (10 mg/kg q24h for 1 month). Proteinuric dogs might need longer treatment as well as medications and diets for protein‐losing nephropathy. The ACVIM diplomates believe the use of Lyme vaccines still is controversial and most do not administer them. It is the consensus opinion that additional research is needed to study predictors of illness, “Lyme nephropathy,” and coinfections in Lyme endemic areas.
Anthelmintic Resistance of Gastrointestinal Parasites in Small Ruminants
Authors: Fleming Sherrill A. , Craig Tom , Kaplan Ray M. , Miller James E. , Navarre Christine , Rings Mike
Published: March 2010

Consensus Statements of the American College of Veterinary Internal Medicine (ACVIM) provide veterinarians with guidelines regarding the pathophysiology, diagnosis, or treatment of animal diseases. The foundation of the Consensus Statement is evidence‐based medicine, but if such evidence is conflicting or lacking, the panel provides interpretive recommendations on the basis of their collective expertise. The Consensus Statement is intended to be a guide for veterinarians, but it is not a statement of standard of care or a substitute for clinical judgment. Topics of statements and panel members to draft the statements are selected by the Board of Regents with input from the general membership. A draft prepared and input from Diplomates is solicited at the Forum and via the ACVIM Web site and incorporated in a final version. This Consensus Statement was approved by the Board of Regents of the ACVIM before publication.