bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Levothyroxine Treatment on Resting Energy Expenditure of Hypothyroid Dogs
Authors: Greco Deborah S. , Rosychuk Rod A.W. , Ogilvie Gregory K. , Harpold Lynn M. , Van Liew Camilla H.
Published: March 2010

Thirty adult, client‐owned dogs were diagnosed with hypothyroidism based on history, physical examination findings, hematologic and biochemical abnormalities, thyrotropin (TSH) response testing, endogenous canine thyrotropin (cTSH) concentration, or both, and total serum thryoxine concentration. All dogs received levothyroxine (L‐thyroxine) at an initial dose of 22 μg/kg PO sid in either a tablet (13 dogs) or chewable form (17 dogs). Energy expenditure of each dog during apparent rest was estimated with an open‐flow indirect calorimetry system by determining the rates of carbon dioxide production and oxygen consumption. Energy expenditure of apparent rest (EE) was lower in untreated hypothyroid dogs compared with reference values for EE. After treatment with L‐thyroxine, EE of the hypothyroid dogs was significantly (P< .05) higher than pretreatment values.
Veterinary Randomized Clinical Trial Reporting: A Review of the Small Animal Literature
Authors: Lund Elizabeth M. , James Katherine M. , Neaton James D.
Published: March 2010

The randomized clinical trial (RCT) is a valuable research method for the evaluation of new treatment and prevention regimens in veterinary medicine. Reporting of clinical trials in other disciplines has not been complete. Without complete information on the conduct and results of a clinical trial, readers cannot optimize their use of the information presented. This report represents an objective review of randomized clinical trials in the veterinary small animal literature from 1986 to 1990. Results indicate that RCT reports in the small animal veterinary literature are incomplete. The importance of reporting on particular aspects of RCT research is described.
Coagulation Abnormalities in 22 Cats with Naturally Occurring Liver Disease
Authors: Lisciandro Stephanie C. , Hohenhaus Ann , Brooks Marjory
Published: March 2010

Twenty‐two cats with liver disease were evaluated for coagulation abnormalities including alterations in prothrombin time, activated partial thromboplastin time, thrombin time, factor VII activity, and platelet count. The purpose of the study was to determine the prevalence of coagulation abnormalities in this population of cats, classify abnormalities according to underlying pathogenesis, and determine if serum biochemical parameters typically used as indicatiors of liver disease showed any correlation with the coagulation abnormalities present. Study results indicated that at least 1 coagulation abnormality was present in 82% of the cats. Prolongation of prothrombin time was most common (16/22 cats) and factor VII activity was below reference range (<60%) in 15 cats. When classified according to underlying pathogenesis, vitamin K deficiency was the most common abnormality found (11/22). Other abnormalities were less common and included hepatic synthetic failure (3/22), indeterminate (3/22), and disseminated intravascular coagulation (1/22). Increase in alkaline phosphatase (ALP) activity was the only biochemical abnormality that showed statistically significant correlation with coagulation abnormalities (P= .023). Cats with marked increases in ALP activity were more likely to have coagulation abnormalities than those with only mild increases in ALP activity.
Use of Serum Protein Concentration to Predict Mortality in Mixed‐Source Dairy Replacement Heifers
Authors: Tyler Jeff W. , Hancock Dale D. , Wiksie Steve E. , Holler Susan L. , Gay John M. , Gay Clive C.
Published: March 2010

The relationship between serum protein concentration in the 1st week of life and survival to 16 weeks of age was examined in 3,479 Holstein replacement heifers over a period of 10 years on a farm with endemic salmonellosis. Thirty‐four percent of calves studied had serum protein concentrations <5.0 g/dL and 60.5% of calves had serum protein concentrations <5.5 g/dL. Cumulative mortality was 7.9%, indicating that calves with marginal passive transfer status can be reared successfully under conditions of endemic salmonellosis. Optimal survival was observed in calves with serum protein concentrations >5.5 g/dL. Calves with serum protein concentrations of 5.0–5.4 g/dL had only a slightly increased relative risk (RR) of mortality (RR = 1.3) compared to calves with serum protein concentrations >5.5 g/dL. The highest RR was experienced by calves with serum protein concentrations <4 g/dL (RR = 4.6) and 4.0–4.4 g/dL (RR = 3.1). Calves with inadequate passive transfer (serum protein concentration <5.0 g/dL), experienced increased mortality until at least 10 weeks of age, indicating that failure of passive transfer has an effect on calf health that extends into the juvenile period. Models in which serum protein concentration was treated either as a continuous variable or as a categorical variable failed to demonstrate any significant interaction between baseline mortality and the RR of mortality. This finding suggests that the RR derived in the present study should be applicable to farms with dramatically different baseline mortality rates.
Juvenile‐Onset Distal Myopathy in Rottweiler Dogs
Authors: Hanson Stephen M. , Smith Mary O. , Walker Tom L. , Shelton G. Diane
Published: March 2010

Two juvenile Rottweiler siblings were presented with the complaint of decreased activity and various postural abnormalities, including plantigrade and palmigrade stance and splayed forepaw digits. The neurologic examinations were otherwise normal. Electromyography revealed rare fibrillation potentials and positive sharp waves. Motor nerve conduction velocities were normal, whereas compound muscle action potentials from the interosseous muscles were decreased. These findings were consistent with a primary myopathy. A 3rd pup from a different litter and a 4th pup from a litter with 3 of 8 affected dogs had similar clinical presentations. Histopathologic changes in fresh‐frozen muscle biopsy samples were similar in all pups and consisted of myofiber atrophy with mild myonecrosis, endomysial fibrosis, and replacement of muscle with fatty tissue. These changes were more severe in distal muscles than in proximal muscles. Plasma carnitine concentrations (total and free) were decreased in all pups. Muscle carnitine concentrations (total and free) were decreased in 3 of 4 pups and the least affected pup had a borderline low free muscle carnitine concentration. Abnormalities involving major metabolic pathways were not found on quantification of organic and amino acids. Dystrophin immunocytochemistry was normal in 2 dogs tested. Distal myopathies in humans are classified under the dystrophic group of muscle disorders. These 4 cases represent a form of muscular dystrophy apparently not previously reported in dogs.
Calcium Channel Blockers in Veterinary Medicine
Authors: Cooke Kirsten L. , Snyder Patti S.
Published: March 2010

Calcium channel blockers are becoming increasingly popular in veterinary medicine for the treatment of systemic hypertension, cardiac arrhythmias, and hypertrophic cardiomyopathy. Calcium is vital to many cellular functions and thus stringent regulation of intracellular calcium concentrations is required. Pharmacologic manipulation of the regulatory mechanisms has the potential to alter cellular function in all body systems. In human medicine, calcium channel blockers are being evaluated for, among other things, use in treating glaucoma, deep vein thrombosis, and pulmonary hypertension, in renal transplantation, and for prevention of reperfusion injury. The potentially beneficial effects of these drugs have often been overshadowed by adverse effects including hypotension, inappetence, bradycardia, conduction abnormalities, and decreased cardiac output. With the introduction of sustained‐ release formulations (diltiazem) and 2nd generation calcium channel blockers (amlodipine) many of these effects have been attenuated or eliminated. This paper will review the functions of calcium and the calcium channels as well as discussing the classes and current and potential uses of the various calcium channel blockers.
A Syndrome Resembling Idiopathic Noncirrhotic Portal Hypertension in 4 Young Doberman Pinschers
Authors: DeMarco JoAnn , Center Sharon A. , Dykes Nathan , Yeager Amy E. , Kornreich Bruce , Gschrey Ed , Credille Kelly A. , Guffroy Magali , del Piero Fabio , Valentine Beth A.
Published: March 2010

We describe 4 young male Doberman Pinschers (3 littermates and 1 unrelated dog) with a syndrome resembling idiopathic or noncirrhotic portal hypertension of humans. Each dog was evaluated for a hepatopathy resulting in portal hypertension, development of portosystemic collateral vessels, and hepatic encephalopathy. These dogs differ from previous reports of young dogs with hepatic insufficiency associated with portal hypertension and acquired portal systemic shunting by their lack of intrahepatic arteriovenous fistulae, portal vein atresia, or intrahepatic fibrosis. Clinicopathologic features included erythrocyte microcytosis, normal to mildly increased liver enzyme activities, increased concentrations of serum bile acids, reduced plasma indocyanine green clearance, and normal total bilirubin concentration. Abdominal ultrasonography disclosed a small liver and portosystemic collateral vessels. Radiographic imaging studies confirmed hepatofugal portal circulation and discounted hepatic arteriovenous fistulae. Histopathologic features in liver tissue from each dog were similar and consistent in all sections examined. Common findings included increased cross‐sectional views of hepatic arterioles; hepatic lobular atrophy; scanty increase in connective tissue around some large portal triads; and absence of inflammation, disturbed lobular architecture, bile duct proliferation, or intrahepatic cholestasis.
Acute Reactions in Dogs Treated with Doxorubicin: Increased Frequency with the Use of a Generic Formulation
Authors: Phillips Brenda S. , Kraegel Susan A. , Simonson Eric , Madewell Bruce R.
Published: March 2010

During a 4‐month period, 34 dogs with tumors received a total of 60 doses of a single generic formulation of doxorubicin; 13 acute drug reactions were observed in these 34 dogs, and no acute reactions were observed after replacing the product with the proprietary brand. These reactions were characterized by one or more of the following signs: pruritus; head‐shaking; urticaria; erythema of the pinnal, axillary, or inguinal regions; vocalization; vomiting; hyperemic or pale mucous membranes; high heart rate; and high respiratory rate. We propose that a component unique to generic doxorubicin was responsible for the unusually high number of acute drug reactions observed.
Skeletal Metastasis as the Initial Clinical Manifestation of Metastatic Carcinoma in 19 Dogs
Authors: Cooley Dawn M. , Waters David J.
Published: March 2010

Although the skeleton represents a potentially important target for the metastatic spread of carcinoma, the clinicopathologic features of skeletal metastases in dogs have not been documented extensively. In particular, no reports have focused on dogs in which skeletal metastasis was the initial clinical manifestation of their malignancy. Medical records were reviewed for dogs with skeletal carcinoma and cases were subdivided into 2 groups based upon the temporal relationship between the diagnosis of carcinoma and recognition of skeletal metastases. In 19 of 24 (79%) dogs, skeletal metastasis was the initial clinical manifestation of malignancy, and these dogs were studied in detail. Most affected dogs were elderly and weighed less than 25 kg. Thirty‐six skeletal lesions were identified in 19 dogs. Skeletal metastases occurred most frequently in the axial skeleton and proximal long bones. Only 4 of 36 (11%) skeletal carcinomas occurred distal to the elbow or stifle. Mammary gland, prostate, and urinary bladder were the most common primary sites. In 11 of 19 (58%) dogs, the primary tumor could not be determined, and in 6 of these dogs, the primary tumor could not be identified despite complete postmortem evaluation. Physical examination and abdominal ultrasonography were most valuable in detecting the primary tumor. Although biopsy or fine‐needle aspirate of skeletal lesions was essential in the diagnosis of skeletal carcinoma, these procedures did not yield definitive information on the primary tumor site. This report documents that the majority of skeletal metastases are diagnosed in dogs without a previous diagnosis of carcinoma. Detection of the primary tumor in these cases may be challenging, and skeletal metastases are frequently attributable to carcinoma of unknown origin.
Pharmacokineatic Aspects of Measurement of Glomerular Filtration Rate in the Dog: A Review
Authors: Heiene Reidun , Moe Lars
Published: March 2010

Glomerular filtration rate (GFR) is estimated by means of clearance, defined as the volume of plasma that has been cleared of a particular substance per unit time. Glomerular filtration rate may be estimated by measuring the renal clearance of a filtration marker using data from both urine and plasma or by plasma clearance using only plasma data. Several alternative pharmacokinetic models are used for the calculation of clearance using various filtration markers with slightly different pharmacokinetic properties. The purpose of this article is to discuss how the choice of marker and pharmnacokinetic model may influence estimated GFR values and to elucidate commonly used methods and reported GFR values in the dog.
Influence of Veterinary Care on the Urinary Corticoid: Creatinine Ratio in Dogs
Authors: van Vonderen Ilse K. , Kooistra Hans S. , Rijnberk Ad
Published: March 2010

Physical and emotional stresses are known to increase the production and secretion of glucocorticoids by the adrenal cortex in both humans and experimental animals. The urinary corticoid: creatinine (C:C) ratio is increasingly used as a measure of adrenocortical function. In this study we investigated whether a visit to a veterinary practice for vaccination, a visit to a referral clinic for orthopedic examination, or hospitalization in a referral clinic for 1.5 days resulted in increases of the urinary C: C ratio in pet dogs. In experiment 1, owners collected voided urine samples from 19 healthy pet dogs at specified times before and after taking the dogs to a veterinary practice for yearly vaccination. In experiment 2, 12 pet dogs were evaluated in a similar way before and after an orthopedic examination at a referral clinic. In experiment 3, 9 healthy pet dogs were hospitalized for 1.5 days and urine samples were collected before, during, and after this stay. Basal urinary C:C ratios in all experiments ranged from 0.8 to 8.3 × 10‐6. In experiment 1, the urinary C:C ratio after the visit to the veterinary practice ranged from 0.9 to 22.0 × 10‐6. Six dogs had a significantly increased urinary C:C ratio (responders), but in 5 of these dogs the ratio was ≤10 × 10‐6In experiment 2. 8 of 12 dogs responded significantly with urinary C:C ratios ranging from 3.1 to 27.0 × 10‐6. In experiment 3, 8 of 9 dogs had significantly increased urinary C:C ratios, ranging from 2.4 to 24.0 × 10‐6, in some or all urine samples collected during hospitalization. In 4 dogs urinary C:C ratios 12 hours after hospitalization were still significantly higher than the initial values. Thus, a visit to a veterinary practice, an orthopedic examination in a referral clinic, and hospitalization can be considered stressful conditions for dogs. A large variation occurs in response, and in individual dogs the increases in urinary C:C ratios can exceed the cutoff level for the diagnosis of hyperadrenocorticism. Therefore, urine samples for measurement of the C: C ratio in the diagnosis of hyperadrenocorticism should be collected in the dog's home environment, to avoid the influence of stress on glucocorticoid secretion.
Treatment of Neonatal Calf Diarrhea with an Oral Electrolyte Solution Supplemented with Psyllium Mucilloid
Authors: Cebra Margaret L. , Garry Franklyn B. , Cebra Christopher K. , Adams Ragan , McCann Joseph P , Fettman Martin J.
Published: March 2010

Dairy calves under 14 days of age with naturally occurring, uncomplicated diarrhea were treated for 3 days with a hypertonic oral electrolyte solution with (n = 15) or without (n = 12) psyllium. Clinical response and clinical pathology data were compared between the 2 groups. Glucose absorption was evaluated on days 1 and 3 by measurement of plasma glucose and lactate and serum insulin concentrations for 4 hours after formula administration. On day 1, glucose, lactate, and insulin concentrations were lower in psyllium‐fed calves than in control calves, with significant differences noted in glucose and lactate concentrations at several time points (P< 0.05). Plasma lactate concentrations were higher at several times in both treatment groups on day 3 than on day 1 (P< 0.05). Fecal consistency was markedly different in psyllium‐fed calves as compared with control calves within 24 hours of psyllium supplementation. Fecal percent dry matter content was lower in psyllium‐fed calves than in control calves at least once a day during supplementation and on day 3 compared with day 0 in the psyllium‐fed calves (P< 0.05). There were no significant differences in clinical performance scores, hydration status, arterial blood gas, serum anion gap, electrolyte, or total CO, concentrations. Addition of psyllium to an oral electrolyte solution resulted in immediate alterations in glucose absorption without impairing rehydration in diarrheic calves, but differences were transient and did not affect clinical outcome.
Retrospective Analysis of the Clinical Utility of Ambulatory Electrocardiographic (Holter) Recordings in Syncopal Dogs: 44 Cases (1991–1995)
Authors: Miller Rita H. , Lehmkuhl Linda B. , Bonagura John D. , Beall Melissa J.
Published: March 2010

The objective of this study was to evaluate retrospectively the clinical utility of ambulatory (Holter) electrocardiographic monitoring in syncopal dogs and to compare the Holter recording with the clinic electrocardiogram (ECG) in these animals. Fifty Holter reports and 44 medical records from 44 dogs were evaluated. A syncopcal episode occurred during monitoring in 24% of the recordings. No obvious relationship was found between the frequency of syncope occurring before Holter recording and the likelihood of a dog having an episode during recording. Holter recordings were helpful in establishing a diagnosis 42% of the time, but no relationship was detected between the frequency of episodes occurring before Holter recording and the likelihood of a diagnostically useful Holter. An arrhythmia was ruled out as the cause of syncope in 12% of the recordings and was implicated as the cause of syncope in 30% of recordings. Of these, 20% were ventricular tachyarrhythmias and 10% were bradyarrhythmias including pacemaker failure. Ambulatory electrocardiographic recordings led to a therapeutic change in 38% of cases.

A comparison of the Holter recordings and clinic ECGs documented the expected increased sensitivity for Holter detection of arrhythmias. The average clinic ECG heart rate consistently exceeded the average Holter heart rate with a mean difference between the average heart rates recorded by the two techniques of 31 bpm (range — 8–87 bpm).
Prediction of Serum IgG1Concentration in Beef Calves Based on Age and Serum Gamma‐Glutamyl‐Transferase Activity
Authors: Wilson Leilani K. , Tyler Jeff W. , Besser Thomas E. , Parish Steven M. , Gant Roderick
Published: March 2010

This study examined the relationship between serum gamma‐glutamyl‐transferase (GGT) activity and passive transfer status in beef calves less than 18 days of age. Immunoglobulin G1(IgG1) concentrations were measured in 69 commercial beef calves between the ages of 24 and 72 hours. GGT activities were then measured in these same calves at various ages between 3 and 18 days of age. Models were developed predicting serum IgG1concentration as a function of calf age and serum GGT activity. Minimal association was present between initial serum IgG1concentration and serum GGT activity when all calves less than 18 days of age were considered (r2= 0.065). When the study population was restricted to calves less than 8 days of age, the fit of the developed model was greatly improved (r2= 0.438). Serum GGT activity has no apparent advantage relative to other assay procedures for predicting passive transfer status in beef calves. If serum GGT activity is to be used to assess passive transfer status in beef calves, application of this procedure should be restricted to calves less than 8 days of age.
Vertebral Plasma Cell Tumors in 8 Dogs
Authors: Rusbridge Clare , Wheeler Simon J. , Lamb Christopher R. , Page Rodney L. , Carmichael Stuart , Brearley Malcolm J. , Bjornson Alexander P.
Published: March 2010

The case histories of 8 dogs with spinal pain and neurologic deficits associated with vertebral plasma cell tumor are reviewed. Four dogs had solitary plasmacytoma, 3 had multiple myeloma, and 1 dog had 2 vertebral lesions with no evidence of disseminated disease. Four dogs were treated: 2 with multiple myeloma received chemotherapy only and survived 17 and 26 months, respectively. Two dogs with solitary plasmacytomas of the spine had chemotherapy and radiotherapy: the 1st survived 4 months and was euthanized after developing radiation myelopathy; the 2nd survived 65 months before developing multiple myeloma. The diagnosis of solitary plasmacytoma of the spine versus multiple myeloma is discussed.
Hypofractionated Radiation Therapy of Brain Masses in Dogs: A Retrospective Analysis of Survival of 83 Cases (1991–1996)
Authors: Brearley Malcolm J. , Jeffery Nick D. , Phillips Susan M. , Dennis Ruth
Published: March 2010

There are few reports of radiation treatment for brain tumors in dogs, and the optimal treatment protocol has yet to be established. We completed a retrospective analysis of the survival times of a series of 83 dogs with intracranial masses that were treated by hypofractionated megavoltage radiation therapy. A total tumor dose of 38 Gray was given over 5 weeks as once weekly fractions via 3 perpendicular portals. The median survival time from the start of radiotherapy for the whole cohort was 43.7 weeks (range, 0.1–172 weeks). Extra‐axial masses had a better survival time (49.7 weeks) than did other intracranial masses (intra‐axial, 40.4 weeks; pituitary, 21.0 weeks). Delayed radiation toxicity was suspected as the cause of death or reason for euthanasia in 12 dogs. The hypofractionated radiation protocol resulted in survival times similar to those obtained using more conventional multifrac‐tionated regimens, and this protocol may be a useful, less intensive alternative treatment for brain tumors in dogs.
Disturbed Vasopressin Release in 4 Dogs with So‐Called Primary Polydipsia
Authors: van Vonderen Ilse K. , Kooistra Hans S. , Sprang Elpetra P.M. , Rijnberk Ad
Published: March 2010

Primary polydipsia is characterized by a marked increase in water intake and secondary polyuria, and in dogs often is described as a behavioral problem or a psychological disorder. We describe 4 dogs with primary polydipsia, diagnosed on the basis of a modified water deprivation test, in which further examination included serial measurements of urine osmolality (UOsm) and plasma vasopressin (VP) measurements during water deprivation and hypertonic saline infusion. The dogs, ranging in age from 4 months to 4 years, all were presented for evaluation of polyuria and polydipsia. Physical examination, routine blood chemistry, and urinalysis disclosed no specific cause for the polyuria and polydipsia. During serial measurements UOsm spontaneously reached high concentrations in 2 dogs, whereas in the other 2 dogs UOsm also fluctuated but on no occasion exceeded 1,000 mosm/kg. Primary polydipsia was diagnosed when UOsm exceeded 1,000 mosm/kg at the end of the modified water deprivation test and plasma osmolality did not exceed the upper limit of the reference range during testing. During water deprivation, plasma VP concentrations remained relatively low. The VP response to hypertonic saline infusion was abnormal, with an increased threshold value in 3 dogs, an increased sensitivity in 2 dogs, and an exaggerated response in 1 dog. It is concluded that some dogs fulfilling current criteria for primary polydipsia produce concentrated urine spontaneously throughout the day in a pattern similar to what has been observed in healthy pet dogs. This finding can be regarded as diagnostic and precludes the need for a water deprivation test. During water deprivation testing, all 4 dogs produced highly concentrated urine in the face of low basal plasma VP concentrations. The observed abnormal VP release in response to hypertonic stimulation may be interpreted as a primary disturbance in the regulation of VP secretion, although it might also be the result of overhydration caused by a primary abnormality in drinking behavior.
Determination of Normal Values Using an Automated Coagulation Timer for Activated Coagulation Time and its Application in Dogs with Hemophilia
Authors: Gerber Bemhard , Taboada Joseph , Lothrop Clinton D. , Busato Andre , Hosgood Giselle , Goodman Susan A. , Gaschen Frédéric P.
Published: March 2010

The present study was performed to determine normal values for the Medtronic HemoTec automated activated coagulation time (ACT) analyzer (Medtronic HemoTec Inc, Parker, CO, distributed in Switzerland by Convergenza AG, Vaduz, Liechtenstein), and to evaluate its ability to detect dogs with hemophilia. ACT was measured in 43 healthy dogs presented to the Companion Animal Hospital, University of Bern, Bern, Switzerland, with the Medtronic HemoTec ACT analyzer to determine normal values. The mean ± 2 standard deviations (SDs) of the values obtained was defined as the normal range. ACT was measured 8–10 times on the same day in 6 dogs to determine repeatability. ACT also was measured in 11 dogs with hemophilia and compared with a conventional visual ACT measurement test and with the activated partial thromboplastin time (APTT). ACT values of the 43 dogs used to determine normal values ranged from 66.5 to 97.0 seconds (mean, 79.3 seconds; SD, 7.35 seconds; median, 78.5 seconds). A range of 64–95 seconds (mean ± 2 SDs) was defined as the normal range for the tested device. Repeatability was poor (r= 0.256). ACT values measured with the automated device did not correlate with ACT values measured with a conventional visual test or with APTT. Sensitivity of the test was 90.9%, specificity was 98.0%, and accuracy was 96.7%. Variability in the test results was large and may lead to incorrect results. The automated measurement device was not superior to the conventional visual method in evaluating dogs with hemophilia.
Clinical Characteristics of 53 Dogs with Doppler‐Derived Evidence of Pulmonary Hypertension: 1992–1996
Authors: Johnson Lynelle , Boon June , Orton E. Christopher
Published: March 2010

Pulmonary hypertension occurs as a primary or secondary disorder of the pulmonary vasculature. Doppler echocardiography provides a noninvasive tool for the estimation of pulmonary arterial pressure when tricuspid regurgitation or pulmonic insufficiency is present. The cardiology database at Colorado State University was reviewed, and echocardiographic records from cases diagnosed with pulmonary hypertension were evaluated. Application of the modified Bernoulli equation to the maximal instantaneous velocity of a right‐sided regurgitant jet provided evidence of pulmonary hypertension in 53 dogs over a 4‐year period. Tricuspid regurgitant velocity ≥ 2.8 m/second or pulmonic insufficiency velocity ≥ 2.2 m/second was considered abnormal and indicative of pulmonary hypertension. Tricuspid regurgitant gradients in 51 dogs ranged from 32 to 145 mm Hg (mean, 63.0 mm Hg; median, 57.0 mm Hg; 25th‐75th percentiles, 45.2–76.5 mm Hg). Pulmonic insufficiency gradients in 8 dogs ranged from 20 to 100 mm Hg (mean, 59.5 mm Hg; median, 61.5 mm Hg; 25th‐75th percentiles, 32.0–84.5 mm Hg). Affected dogs ranged in age from 2 months to 16 years. Clinical signs were characteristic of cardiopulmonary disease, but a relatively high frequency of syncope was noted (12 of 53 dogs, 23%). Pulmonary hypertension was probably due to increased pulmonary vascular resistance in 23 dogs, pulmonary overcirculation in 2 dogs, and pulmonary venous hypertension in 23 dogs. Five dogs lacked a clinically recognizable cardiopulmonary cause of pulmonary vascular disease. Our results suggest that pulmonary hypertension can occur as a complication of commonly encountered cardiopulmonary diseases, and that Doppler echocardiography can facilitate recognition of this condition.
Prednisone and Vinblastine Chemotherapy for Canine Mast Cell Tumor—41 Cases (1992–1997)
Authors: Thamm Douglas H. , Mauldin Elizabeth A. , Vail David M.
Published: March 2010

Forty‐one dogs with mast cell tumors (MCTs) were treated with oral prednisone and injectable vinblastine (VBL), both in the adjuvant setting (23 dogs) and in dogs with gross disease (18 dogs). Adverse effects were noted in 20% (8/41) of the patients, usually after the 1st dose of VBL. Adverse effects were considered mild in 6, and severe, necessitating treatment discontinuation, in 2 (5%). Overall response rate in the evaluable dogs with gross disease was 47% (7/15), consisting of 5 complete responses and 2 partial responses. Median response duration was 154 days (24 to >645 days). As adjuvant therapy to incomplete surgical resection, prednisone and VBL conferred a 57% 1‐ and 2‐year disease‐free rate. Median survival time (MST) for the entire patient population was not reached with a median follow‐up of 573 days; however, the MST for dogs with grade III MCT was 331 days, with 45% of dogs alive at 1 and 2 years. This is an apparent improvement over historical survival data employing surgery alone. Upon univariate analysis, significant prognostic factors (P< .05) for survival included presence of a locally recurrent tumor, presence of gross disease, argyrophilic nucleolar organizer region frequency, lymph node status, histologic grade, previous chemotherapy, and ulceration of the tumor. Similar criteria were significant when analyzed for time to treatment failure. Response to therapy was also predictive of survival in the gross disease group. Upon multivariate analysis, histologic grade (P= .012) and presence of a locally recurrent tumor (P< .001) were significant factors for survival.
Effects of Renal Impairment on the Disposition of Orally Administered Enalapril, Benazepril, and Their Active Metabolites
Authors: Lefebvre Hervé P. , Laroute Valérie , Concordet Didier , Toutain Pierre‐Louis
Published: March 2010

The pharmacokinetics of benazepril, enalapril, and their active metabolites (benazeprilat and enalaprilat) were compared after a single administration of each product by the oral route at the recommended dosage (0.5 mg/kg for both drugs) in the dog before and after moderate experimental renal impairment. Ten dogs were randomly assigned to 2 groups of 5 animals in a 2‐period crossover design for angiotensin‐converting enzyme inhibitor administration. Renal failure was surgically induced by right ne‐phrectomy and electrocoagulation of the remaining kidney. Renal mass reduction induced a significant decrease (P< .001) in glomerular filtration rate (GFR) (1.7 ± 0.3 versus 3.3 ± 0.7 mL/kg/minute). No significant differences before and after surgery were observed for enalapril and benazepril kinetics. The area under the curve (AUC) for enalaprilat increased after surgery from 23.6 ± 14.7 to 42.4 ± 20.9 μg‐minute/mL (P< .01). Mean peak plasma concentration (Cmax) was increased in the impaired dogs (59.1 ± 23.3 versus 43.9 ± 32.9 ng/mL), but this variation was not significant (P> .05). Renal failure had no significant effect on AUC for benazeprilat (13.8 ± 9.8 versus 14.9 ± 5.0 μg‐minute/mL) (P> .05), but Cmaxdecreased significantly (from 55.0 ± 26.4 to 31.9 ± 17.7 ng/mL) (P< .05). Multiple regression analysis showed that both GFR and AUC for enalapril were highly significant variables that explained the variation in AUC for enalaprilat (R2= .86,P< .001) but not for benazeprilat (R2= .12,P> .05). The results of this study indicate that exposure to enalaprilat, but not to benazeprilat, is increased in dogs with subclinical renal impairment.
Prevalence of Feline Chlamydia psittaci and Feline Herpesvirus 1 in Cats with Upper Respiratory Tract Disease
Authors: Sykes Jane E. , Anderson Garry A. , Studdert Virginia P. , Browning Glenn F.
Published: March 2010

The epidemiology of feline chlamydiosis and feline herpesvirus 1 (FHV1) infection in cats was determined using a duplex polymerase chain reaction assay. In cats with upper respiratory tract disease (URTD), prevalences of 66 (14.3%) of 462 cats and 98 (21.2%) of 462 cats were found forChlamydia psittaciand FHV1, respectively. In cats without URTD, prevalences were 1/87 (1.1%) for both pathogens. Younger cats, cats sampled in summer, and cats with conjunctivitis were more likely to be positive forC psittacithan were cats sampled in other seasons and cats without conjunctivitis. Cats with recent contact with cats outside the household, cats with acute disease, and sneezing cats were more likely to be positive for FHV1 than were cats that had not had recent contact with cats outside the household, cats with chronic disease, and cats that were not sneezing. Purebred cats were less likely to be positive for FHV1 than were mixed breed cats and prevalence varied with year of sampling. Coinfection with both pathogens was lower than would be expected from their respective prevalences. Vaccinated cats were equally likely to be positive for FHV1 as unvaccinated cats. In sneezing cats FHV1 was more likely to be detected thanC psittaci,particularly in acute cases, and when sneezing was not accompanied by conjunctivitis. Cats with reproductive disease concurrent with URTD were more likely to be infected with FHV1 than withC psittaci.Thus, the factors that should be considered in clinical diagnoses ofC psittaciinfections are the presence of conjunctivitis, age, and season, whereas contact with other cats, acute disease, and sneezing should be considered in diagnoses of FHV1 infection.
Prognostic Value of Argyrophilic Nucleolar Organizer Region (AgNOR) Staining in Feline Intestinal Lymphoma
Authors: Rassnick Kenneth M. , Mauldin G. Neal , Moroff Scott D. , Mauldin Glenna E. , McEntee Margaret C. , Mooney Samantha C.
Published: March 2010

Limited information is available on prognostic factors for cats with lymphoma. The quantity of argyrophilic nucleolar organizer region (AgNOR) proteins can be used as a measurement of cellular proliferative activity. To determine if AgNORs were of prognostic value for feline intestinal lymphoma, the silver staining technique was performed on paraffin‐embedded sections of 31 cases. Mean number of AgNORs per nucleus ranged from 1.02 to 4.32. Twenty‐four (78%) cats had small AgNORs and 7 (22%) had large AgNORs. All cats were treated identically with a combination chemotherapy protocol. Response to chemotherapy was 87%. Median remission duration and survival times were 120 days and 201 days, respectively. No significant correlation was found between mean number of AgNORs per nucleus or AgNOR size and remission rate, remission duration, or survival time. This study indicates that AgNOR staining is not a useful prognostic factor for cats with intestinal lymphoma.
Gene Defect of Dermatan Sulfate Proteoglycan of Cattle Affected With a Variant Form of Ehlers‐Danlos Syndrome
Authors: Tajima Motoshi , Miyake Sachiko , Takehana Kazushige , Kobayashi Ataru , Yamato Osamu , Maede Yoshimitsu
Published: March 2010

A defect of the core protein of dermatan sulfate proteoglycan was suspected in a Holstein calf affected with a variant form of Ehlers‐Danlos syndrome. The mutation was a guanine‐to‐adenine transition at nucleotide position 254, which resulted in a serineto‐asparagine substitution of the bovine proteoglycan core protein. This substitution occurred in the serine–glycine dipeptide repeat that was suspected to be the binding portion of dermatan sulfate. This point mutation in the genome was also detected by the use of restriction fragment length polymorphism (RFLP) and polymerase chain reaction (PCR) methods. The results of the RFLP and PCR indicated that the calf was a heterozygote of an abnormal gene and a normal gene of the core protein. The interpretation of these data revealed that the functional abnormality in cutaneous tissues of the calf was caused by an abnormal gene of the proteoglycan core protein, which induced a substitution of amino acid.
Naturally Occurring Scrapie in Southdown Sheep
Authors: Tyler Jeff W. , Weaver Dusty M. , Turk James R. , O'Rourke Katherine I. , Harrington Michael G. , Taylor William , Jenny Allen
Published: March 2010

The purpose of this study was to characterize naturally occurring scrapie in the Southdown breed of sheep. Experimental subjects included 4 Southdown ewes admitted to the University of Missouri, College of Veterinary Medicine Large Animal Clinic. All 4 sheep had signs compatible with clinical scrapie. Cerebrospinal fluid (CSF) cell counts ranged from a low of 1 nucleated cell/mL to high of 4 cells/mL with a median of 3 cells/mL. Cerebrospinal protein concentrations ranged from 26 to 78 mg/dL with a median of 53 mg/dL. Immunoassay of the CSF for the 14–3–3 protein yielded positive results in 3 of the 4 sheep. Sequencing of the prion protein (PrP) gene revealed that all 4 sheep were homozygous for glutamine at codon 171 and, hence, were of the QQ genotype. Histopathologic examination of brain stem tissue sections revealed intracytoplasmic neuronal vacuolation and mild spongiform changes in the gray matter neuropil in all 4 ewes. The diagnosis of scrapie was confirmed by immunohistochemical staining for the abnormal PrP. Our results suggest that the genetics of scrapie susceptibility are probably similar in Suffolk and Southdown sheep. Positive immunoassay results for the 14–3–3 protein were observed in 3 of the 4 sheep.
Immune‐Mediated Neutropenia in 2 Dogs
Authors: McManus Patricia M. , Litwin Chaim , Barber Lisa
Published: March 2010

Immune‐mediated neutropenia, also termed autoimmune neutropenia (AIN), is an uncommon event, rarely documented within veterinary literature, although the clinical profile and probable pathogenesis have been outlined in detail within medical literature. In this paper, we review 2 different manifestations of this disorder. The 1st case primarily involved peripheral destruction of mature neutrophils, with little impact on marrow precursors, whereas the 2nd case resulted in suppression of neutrophilic granulopoiesis within marrow. In both cases, absolute neutrophil counts dropped below 200/mL.
Hemothorax in 2 Horses
Authors: Perkins Gillian , Ainsworth Dorothy M. , Yeager Amy
Published: March 2010

This report documents the successful conservative medical management of hemothorax in 2 horses. Hemothorax occurred after a lung biopsy procedure (horse 1) and strenuous exercise on a treadmill (horse 2). The horses had tachypnea, tachycardia, nostril flaring, hemoptysis, and pawing. Hemothorax was suspected based upon absence of auscultable ventral lung sounds; development of cool extremities and pale, tacky mucous membranes; the ultrasonographic appearance of moderate to severe amounts of pleural fluid; and a concurrent decrease in hematocrit and total plasma protein. Both horses were treated successfully by intranasal administration of oxygen, intravenous administration of balanced polyionic solutions, and treatment with antibiotics, nonsteroidal anti‐inflammatory drugs, and analgesics. In neither case was pleural blood removed. The hemothorax resolved in both horses without lasting abnormalities. Hemothorax does not require drainage for successful resolution.
Progression of Chronic Renal Disease in the Dog
Authors: Finco Delmar R. , Brown Scott A. , Brown Cathy A. , Crowell Wayne A. , Cooper Tanya A. , Barsanti Jeanne A.
Published: March 2010

Progressive loss of nephron function may be caused by persistence of factors that initiated renal disease. However, newer studies suggest that nephron damage is self‐perpetuating once renal mass is reduced to some critical level. Original theories on mechanisms of self‐perpetuated nephron injury focused on intraglomerular hypertension and glomerular hypertrophy, but several other factors have now been incriminated, including tubulointerstitial responses, proteinuria, and oxidative stress. Studies of dogs with surgically reduced renal mass (remnant kidney model of chronic renal disease) have allowed investigation of the self‐progression theory in this species. Use of this model eliminates pre‐existing renal disease as a confounding factor. Data from these studies indicate that self‐perpetuated renal injury is initiated when mild azotemia is induced (plasma creatinine concentration = 2 to 4 mg/dL). Thus, with naturally occurring renal disease(s), it is likely that self‐perpetuated nephron damage is occurring before or at the time when most cases of chronic renal disease are diagnosed. In dogs with remnant kidneys, loss of renal function often occurs at a linear rate over time, but non‐linear patterns are common as well. The reciprocal of plasma creatinine concentration, which has been used to monitor rate of progression, is only a fair marker of renal function when compared to GFR. Thus, clinical results from creatinine measurements on cases of naturally occurring disease should not be interpreted too stringently. In remnant kidney dogs, the magnitude of proteinuria (UPC ratio) was not predictive of the rate in decline of GFR, casting doubt on importance of proteinuria in causing progression of renal disease. However, progressive increases in UPC may be a marker of an accelerated rate of renal injury. Self‐perpetuation of renal injury in dogs could be the sole mechanism by which naturally occurring renal diseases progress. When more information is available on the rate of progression of naturally occurring diseases, it may become apparent whether factors initially inciting renal damage have an additive effect on rate of progression.
Detection and Effects on Platelet Function of Anti‐Platelet Antibody in Mule Foals with Experimentally Induced Neonatal Alloimmune Thrombocytopenia
Authors: Ramirez Sammy , Gaunt Stephen D. , McClure Jill J. , Oliver Julian
Published: March 2010

Horse mares carrying mule foals were immunized during the last trimester of pregnancy with whole acid‐citrate‐dextrose‐antico‐agulated donkey blood to experimentally induce neonatal alloimmune thrombocytopenia. Thrombocytopenia occurred in the neonatal mule foals born to immunized horse mares within 24 hours after ingestion of their dams' colostrum. Mule foals born to mares not immunized with donkey blood did not develop thrombocytopenia. These findings suggest that antibodies may have been directed against a donkey platelet antigen present in the mule foals but not present in their dams. The objectives of this study were to determine whether anti‐platelet antibody could be detected in mule foals with experimentally induced neonatal alloimmune thrombocytopenia, to identify any platelet proteins recognized by serum antibody in these foals, and to determine if platelet function was altered by sera from these mule foals. An indirect enzyme‐linked immunosorbent assay demonstrated significantly higher absorption at 1:200 of platelet‐bindable immunoglobulin G in serum from thrombocytopenic mule foals, compared with nonthrom‐bocytopenic mule foals. Sera from thrombocytopenic and nonthrombocytopenic mule foals produced similar binding patterns in western immunoblots with donkey platelet proteins separated on sodium dodecyl sulfate polyacrylamide gels. Maximal platelet aggregation and relative slope of aggregation in response to collagen were significantly inhibited after incubation with sera from thrombocytopenic mule foals. These results suggest that mule foals with induced alloimmune thrombocytopenia have serum antibodies that bind to platelets and may compete with collagen binding sites to impair platelet aggregation.
Analysis of Blood Clotting Factor Activities in Canine Legg‐Calvé‐Perthes' Disease
Authors: Brenig Bertram , Leeb Tosso , Jansen Stephan , Kopp Thorsten
Published: March 2010

Legg‐Calve‐Perthes' (LCP) disease is a noninflammatory aseptic necrosis of the femoral head and neck in small‐breed dogs. The etiology of the disease is not known, but ischemia resulting from vascular compression or occlusion has been proposed. A latent ischemic phase during development of the femoral epiphysis seems to be responsible for the onset of the typical clinical features of LCP disease. Ischemia might result from insufficient oxygen supply either caused by a reduced number of afferent arterial vessels or an occlusion of the efferent venous vessels by thrombosis. In humans, LCP disease has been linked to hypercoagulability and hypofibrinolysis caused by deficiencies of protein C, protein S, or resistance to activated protein C. To determine whether canine LCP disease is caused by similar deficiencies, we determined protein C, protein S, activated protein C, factor II, factor V, factor VIII:C, and AT III activities in plasma samples of 18 dogs with clinically and histopathologically verified LCP disease. All dogs had normal plasma activities of these factors, indicating that in these dogs LCP disease was not caused by deficiencies of the analyzed blood clotting factors.
Plasma Granulocyte Colony‐Stimulating Factor Concentrations in Neutropenic, Parvoviral Enteritis‐Infected Puppies
Authors: Cohn Leah A. , Rewerts Jennifer M. , McCaw Dudley , Boon G. Daniel , Wagner‐Mann Colette , Lothrop Clinton D.
Published: March 2010

We evaluated the temporal relationship between neutrophil numbers and plasma granulocyte colony‐stimulating factor (G‐CSF) concentrations in dogs infected with canine parvovirus, a common infectious cause of neutropenia. G‐CSF is produced in response to neutropenia, infection, or inflammation, and results in the production and release of neutrophils from the bone marrow. Adequate numbers of functional neutrophils are necessary for protection from infection, and the timely production of G‐CSF is a crucial response to certain diseases. The relationship between peripheral neutrophil numbers and plasma G‐CSF concentrations during the course of an infectious disease characterized by neutropenia has not been described previously in dogs. Eight mixed‐breed puppies were given an oronasal challenge with canine parvovirus, and peripheral neutrophil numbers as well as plasma G‐CSF concentrations were measured daily. G‐CSF was not detectable in plasma of any dog before the onset of neutropenia, but G‐CSF became detectable just after the onset of neutropenia in the 7 dogs that developed clinical illness. Neutropenia persisted or worsened for at least 2 days after plasma G‐CSF became detectable in all 7 dogs. Neutrophil nadir, the highest plasma G‐CSF concentrations, and the most severe clinical illness occurred concurrently in most dogs. Although 1 dog died while still neutropenic, plasma G‐CSF concentrations declined before resolution of neutropenia in the other 6 dogs, and were again below the limits of detection in 5 of the 6 dogs at the time of resolution.