bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased Pulmonary Transit Times in Asymptomatic Dogs with Mitral Regurgitation
Authors: Lord Peter , Eriksson Anders , Haggstrom Jens , Järvinen Anna‐Kaisa , Kvart Clarence , Hansson Kerstin , Maripuu Enn , Mäkelä Olli
Published: March 2010

Pulmonary transit time (PTT) normalized to heart rate (nPTT) is a measure of the pulmonary blood volume (PBV) to stroke volume ratio (PBV/SV). It is an index of cardiac performance. To determine the effect of compensated mitral regurgitation (CMR) and decompensated mitral regurgitation (DMR) caused by valvular endocardiosis on the index nPTT, we measured nPTT by first‐pass radionuclide angiocardiography and ECG in 13 normal dogs, 18 dogs with CMR, and 13 dogs with DMR. PTT was measured as time between onset of appearance of activity at the pulmonary trunk and the left atrium. In the normal dogs, the relationship between PTT and mean R‐R interval (mRR) was PTT = 4.08 X mRR + 0.15 (R2= 0.71). Normal nPTT was 4.4 ± 0.6 (SD) (range, 3.6‐5.3), in CMR, 6.3 ± 1.6 (SD) (range, 4.0–9.7), and in DMR, 11.9 ± 3.4 (SD) (range, 8.0–18.8). The differences among all groups were significant. Heart rates were 110 ± 22 bpm in normal dogs, 111 ±20 in dogs with CMR, and 144 ± 18 in dogs with DMR P < 001 for difference between DMR group and normal and CMR groups). Increased nPTT in CMR indicates preclinical heart pump dysfunction. Heart rate‐normalized pulmonary transit times may be a useful index of heart function in mitral regurgitation.
The Utility of Plasma D‐dimer to Identify Thromboembolic Disease in Dogs
Authors: Nelson O. Lynne , Andreasen Claire
Published: March 2010

This prospective study was designed to investigate D‐dimer concentrations in clinically healthy dogs, clinically ill dogs without thromboembolic disease (TE), and dogs with TE. The goals of this study were to determine whether the coagulation cascade is activated in nonembolic metabolic and inflammatory conditions and whether differentiation from TE is possible. Group 1 consisted of 30 clinically healthy dogs presented for routine care. Group 2 consisted of 67 clinically ill dogs without TE. This group was subdivided into the following categories: postoperative surgical procedures, congestive heart failure, renal failure, hepatic disease, and neoplastic disease. Group 3 consisted of 20 dogs diagnosed with TE. A CBC and a measurement of prothrombin time (PT), activated partial thromboplastin time (PTT), fibrinogen degradation product (FDP) concentration, and plasma D‐dimer concentration was performed on dogs in all groups. D‐dimer concentrations were highest in dogs with TE; next highest was the hepatic disease group. Only these 2 groups had median D‐dimer concentrations markedly different from clinically healthy dogs. The frequency of platelet abnormalities was markedly greater for the TE and neoplastic disease groups. The sensitivity of D‐dimer concentrations > 500 ng/mL for predicting TE was 100%; however, the specificity of D‐dimer for TE at that concentration was 70%. The specificity of D‐dimer concentrations ± 1,000 ng/mL to predict TE was 94% (sensitivity, 80%), and the specificity of D‐dimer concentrations > 2,000 ng/mL was 98.5% (sensitivity, 36%). FDPs were not high in any TE patient; thus, they may be an insensitive indicator of thromboembolism, with or without overt disseminated intravascular coagulation (DIC).
Effects of Age and Dietary β‐Carotene on Immunological Variables in Dogs
Authors: Massimino Stefan , Kearns Robert J. , Loos Kathleen M. , Burr John , Park Jean Soon , Chew Boon , Adams Scott , Hayek Michael G.
Published: March 2010

β‐Carotene is a naturally occurring carotenoid reported to have health‐promoting effects in several species. Advancing age is known to have a negative impact on various immune variables in several species. This study was conducted in order to assess the effect of age on immune response in dogs and to determine whether β‐carotene is able to reverse this age‐associated decline. To test this hypothesis, young and old dogs (n = 36) were fed either a control diet or experimental diets containing supplemental β‐carotene for 2‐month periods. Age significantly (P < .05) lowered CD4+ T cell populations (47.2% versus 33.7%; young‐control versus old‐control, respectively) and pj‐carotene restored percent distributions in old dogs to nonsignificance versus younger controls (41.0%). T cell proliferation was lower in old dogs (30,254 ±2,248 versus 14,811 ±2,497 cCPM; young‐control versus old‐control, respectively; P < .05), and pj‐carotene supplementation significantly improved responses in this age group (21,329 ±2,275 cCPM). Although B cell proliferation was depressed with age (17,967 ±1,384 versus 7,535 ±1,469 cCPM; young‐control versus old‐control, respectively; P < .05), pj‐carotene supplementation improved B cell proliferation in young dogs (23,500 ±1,339 cCPM). Old dogs displayed lower delayed‐type hypersensitivity test (DTH) responses versus younger controls to both phytohemagglutinin‐P (PHA; 11.1 ± 0.95 versus 7.57 ±1.15 mm; young‐control versus old‐control, respectively; P < .05) and sheep red blood cell (RBC; 9.12 ±0.62 versus 8.08 ±0.75 mm; young‐control versus old‐control, respectively; P < .10). β‐Carotene improved these responses, mostly within the first 24–48 hours after injection. In summary, older dogs have lower immunological responses compared with younger controls. β‐Carotene supplementation significantly restored immune responses in older dogs when compared with their age‐matched controls and younger counterparts.
Feline Intracranial Neoplasia: Retrospective Review of 160 Cases (1985–2001)
Authors: Troxel Mark T. , Vite Charles H. , van Winkle Thomas J. , Newton Alisa L. , Tiches Deena , Dayrell‐Hart Betsy , Kapatkin Amy S. , Shofer Frances S. , Steinberg Sheldon A.
Published: March 2010

The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 ±3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.
Hypomagnesemia in Hospitalized Horses
Authors: Johansson Anna M. , Gardner Sarah Y. , Jones Samuel L. , Levine Jay F.
Published: March 2010

This study was initiated to identify the signalment and clinical variables potentially associated with hypomagnesemia in horses evaluated at the North Carolina State University, College of Veterinary Medicine (NCSU‐CVM) veterinary teaching hospital between January 1999 and May 2001. A nested case reference study (nested case‐control study) was conducted to examine the potential relationship between hypomagnesemia and signalment, serum chemistry panel analyses, number of hospitalization days, discharge status, and diagnosis. A series of independent and multivariable logistic regression models were used to assess the potential association of each variable with low total serum magnesium concentrations. Four hundred one of 823 (48.7%) horses had serum total magnesium concentrations below the normal reference range. Hypomagnesemia was more likely to occur in horses older than 1 month of age. Colic (odds ratio [OR]: 2.96, 95% confidence intervals [CI]: 2.14–4.08), acute diarrhea (OR: 5.91, 95% CI: 2.32–15.06), other gastrointestinal disease (OR: 2.07, 95% CI: 1.15–3.71), infectious respiratory disease (OR: 5.07, 95% CI: 2.09–12.28), and multiorgan system disease (OR: 2.31, 95% CI: 1.24–4.28) were associated with hypomagnesemia in adult horses, whereas foals with diarrhea (excluding septic foals) (OR: 0.11, 95% CI: 0.01–0.84) were less likely to have hypomagne‐semia. Overall, there was no relationship between hypomagnesemia and mortality (OR: 1.00, 95% CI: 0.72–1.41), but horses with colic and hypomagnesemia were less likely to die than horses with colic and normal or high total magnesium (OR: 0.53, 95% CI: 0.30–0.95). Among horses that survived, hypomagnesemia at admission was associated with a longer hospitalization period (OR: 1.45, 95% CI: 1.00–2.11).
Clinical and Prognostic Significance of Radiographic Pattern, Distribution, and Severity of Thoracic Radiographic Changes in Neonatal Foals
Authors: Bedenice D. , Heuwieser W. , Brawer R. , Solano M. , Rand W , Paradis M.R.
Published: March 2010

A total of 207 thoracic radiographs obtained from 128 foals were evaluated to assess the impact of pulmonary radiographic pattern, distribution, and severity of pulmonary changes on short‐term survival of neonatal foals. The association between selected clinical variables and the radiographic manifestation of neonatal respiratory disease was also investigated. The evaluation of interstitial and alveolar‐interstitial radiographic patterns within the caudodorsal, caudoventral, and cranioventral lung regions proved to be highly reliable between viewers in the study. A diagnosis of systemic inflammatory response syndrome was related to increased pulmonary infiltrates within the caudodorsal lung region. Dyspneic foals had more extensive pulmonary infiltrates within the cranioventral lung, advanced respiratory disease, and lower survival rates. A fibrinogen concentration >400 mg/dL was associated with increased cranioventral radiographic abnormalities. In addition, tachypnea most consistently related to diffuse (caudodorsal, caudoventral, and cranioventral) pulmonary changes. Neutropenia, milk reflux from the nares, upper airway pathology, abnormal respiratory sounds, failure of transfer of passive immunity (IgG concentration <400 mg/dL), immaturity, or fever, however, were not related to radiographic pattern, distribution, or severity of radiographic changes. Sixty‐five percent of foals with radiographic pulmonary disease were discharged alive from our referral hospital. Concurrent caudodorsal and caudoventral radiographic disease was most frequently observed in this foal population. Increased caudodorsal radiographic scores retained statistical significance as a prognostic indicator for nonsurvival in a multiple stepwise logistic regression analysis.
Furosemide Continuous Rate Infusion in the Horse: Evaluation of Enhanced Efficacy and Reduced Side Effects
Authors: Johansson Anna M. , Gardner Sarah Y. , Levine Jay F. , Papich Mark G. , Reagan Virginia H. , Atkins Clarke E.
Published: March 2010

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin‐angiotensin‐aldosterone system (RAAS) in the horse. Five mares were used in a crossover‐design study. During a 24‐hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1,110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2,378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half‐lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.
A Retrospective Analysis of Hepatic Injury in Horses with Proximal Enteritis (1984–2002)
Authors: Davis Jennifer L. , Blikslager Anthony T. , Catto Katrina , Jones Samuel L.
Published: March 2010

The purpose of this study was to test the hypothesis that horses with proximal enteritis (PE) are predisposed to hepatic injury. We also determined whether the presence of liver injury in horses with PE was associated with other clinicopathologic abnormalities or affected outcome. The medical records of all horses admitted for evaluation of colic and gastric reflux between 1984 and 2002 were reviewed. Horses were considered to have PE if the diagnosis was made at surgery or postmortem examination or if they had clinical findings consistent with PE. Horses with a small intestinal strangulating obstruction (SISO) were used as the control group. Historic and clinicopathologic data were collected for each horse. The data were analyzed by descriptive statistics, parametric and nonparametric analyses, and logistic regression. Horses with PE had significantly higher serum gamma‐glutamyltransferase (GGT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) activities than horses with SISO(P< .05). Horses with PE were 12.1 times more likely to have high GGT activities than were horses with SISO. Horses with PE had an increased risk of at least 1 hepatic enzyme being increased if a high anion gap or large volume of reflux was present. Our conclusion is that horses with PE are more likely to have hepatic injury than horses with SISO. The mechanism of hepatic injury may involve ascending infection from the common bile duct, absorption of endotoxin or inflammatory mediators from the portal circulation, or hepatic hypoxia resulting from systemic inflammation and endotoxemic shock.
The Relationship between Endogenous Cortisol, Blood Micronutrients, and Neutrophil Function in Postparturient Holstein Cows
Authors: Cebra Christopher K. , Heidel Jerry R. , Crisman Russell O. , Stang Bernadette V.
Published: March 2010

Neutrophil function, blood micronutrients, and cortisol concentrations were measured in 43 clinically healthy postparturient Holstein cows. Estimated 305‐day mature equivalent milk production and neutrophil function were related to results of the blood micro‐nutrient concentrations and neutrophil function tests. Cattle had low to normal zinc concentrations; normal to high selenium, vitamin E, and cortisol concentrations; and normal copper concentrations. Blood selenium(P= .03) and zinc (P= .027) concentrations were both significant predictors of neutrophil adhesion, and selenium (P< .001) was a significant predictor of neutrophil cytochrome C reduction (superoxide production). Fourteen of 20 (70%) cattle with blood selenium concentrations >300 ng/mL had neutrophil adhesion, and 15 of 20 (75%) had cytochrome C reduction above the mean value for this group. There was also a significant correlation (r= 0.331;P= .037) between cytochrome C reduction and estimated milk production. These findings suggest that neutrophils from postparturient dairy cows with higher blood concentrations of selenium have greater potential to kill microbes, and that cattle with greater superoxide production may have higher milk production.
Lymphocyte Blastogenic Responses to Inciting Food Allergens in Dogs with Food Hypersensitivity
Authors: Ishida Rinei , Masuda Kenichi , Kurata Keigo , Ohno Koichi , Tsujimoto Hajime
Published: March 2010

Lymphocyte blastogenic responses against food allergens in dogs with food hypersensitivity were evaluated in this study. Eleven dogs with food hypersensitivity, based on food elimination and oral food provocation tests and allergic responses to food allergens, were examined by various tests such as intradermal testing, antigen‐specific IgE testing, and lymphocyte blastogenic responses. The number and kinds of food allergens identified as positive by these tests were compared with the offending food allergens that were found in an oral food provocation test. In 9 (82%) of the 11 dogs with food hypersensitivity, there was close agreement for positive allergens between the results of lymphocyte blastogenic responses and oral food provocation test; however, there was little agreement for intradermal and IgE testing of the positive allergens with those of the oral food provocation test (11% and 31%, respectively). In the 9 dogs, the stimulation indices of lymphocyte blastogenic responses increased to 2.0–10.1 upon food provocation but decreased significantly to 0.7‐1.4 upon feeding the elimination diet until clinical signs disappeared. These results indicate that lymphocyte blastogenic responses may fluctuate because of exposure to offending food allergens in dogs with food hypersen‐sitivity. Lymphocytes reactive to food allergens may play an important role in the pathogenesis of food hypersensitivity in dogs.
Management of Advanced Tracheal Collapse in Dogs Using Intraluminal Self‐Expanding Biliary Wallstents
Authors: Moritz Andreas , Schneider Matthias , Bauer Natali
Published: March 2010

Twenty‐four client‐owned dogs with tracheal collapse refractory to conventional treatment underwent management with an intraluminal self‐expanding stainless‐steel endoprosthesis (WallstentTM). Initial improvement of clinical signs was observed in 95.8% of the dogs. Two dogs (8.3%) died within a median interval of 6 days after stent implantation due to incorrect placement and size of the stent and emphysema, respectively. A dry cough occurred temporarily in most of the patients. One dog each (4.1%) suffered mild transient tracheal hemorrhage and pneumomediastinum. The results showed that the initial survival rate of intraluminal stabilization was comparable with surgical implantation of extratracheal prostheses. Clinical reevaluation was performed in 18 dogs within a median interval of 68 days after treatment. Of the dogs treated, 30.4% were reported to be asymptomatic after stent implantation, 60.9% improved markedly, and 4.3% remained symptomatic. In all patients undergoing endoscopy, the Wallstents were almost completely covered with tracheal epithelium. A median shortening of 27.3% of the endoprosthesis within a median interval of 175 days after stent implantation in 15 of 18 dogs was noted. The shortening was associated with clinical signs in 2 patients. In 5 dogs, steroid‐responsive granuloma formation resulted in a severe reduction of the tracheal lumen in 3 patients. The results suggest that implantation of Wallstents was minimally invasive and provided stabilization of collapsed thoracic tracheal portions in addition to the cervical part of the trachea. This minimally invasive method for the management of severe tracheal collapse therefore provides an attractive alternative to surgery.
Systemic Absorption of Amitriptyline and Buspirone after Oral and Transdermal Administration to Healthy Cats
Authors: Mealey K.L. , Peck K.E. , Bennett B.S. , Sellon R.K. , Swinney G.R. , Melzer K. , Gokhale S.A. , Krone T.M.
Published: March 2010

A prospective study was performed to determine the relative availability of buspirone and amitriptyline after oral and transdermal routes of administration in 6 adult cats. For topical administration, drugs were compounded in a transdermal organogel containing pluronic and lecithin (PLO). Using a crossover design, each cat received a single dose of amitriptyline (5 mg) and buspirone (2.5 mg) by the transdermal and oral route of administration with at least a 2‐week washout interval between drug treatments. Blood samples were obtained at 0, 0.5, 1, 2, 4, 6, 8, 10, and 12 hours after drug administration for determination of plasma drug concentrations. Plasma concentrations of immunoreactive amitriptyline and buspirone were determined using commercial enzyme‐linked immunosorbent assay (ELISA) tests. Systemic absorption of amitriptyline and buspirone administered by the transdermal route was poor compared with the oral route of administration. Until supporting pharmacokinetic data are available, veterinarians and cat owners should not rely on the transdermal route of administration for treating cats with amitriptyline or buspirone. Key Words: Cat; Pharmacokinetics.
Superficial Necrolytic Dermatitis in 11 Dogs with a History of Phenobarbital Administration (1995–2002)
Authors: March Philip A. , Hillier Andrew , Weisbrode Steven E. , Mattoon John S. , Johnson Susan E. , DiBartola Stephen P. , Brofman Peter J.
Published: March 2010

The clinical records of 11 dogs with histologically confirmed superficial necrolytic dermatitis (SND) and a history of phenobarbital (PB) administration (SND/PB) were evaluated retrospectively (1995–2002). Historical, clinical, clinicopathologic, ultrasonographic, and pathologic findings were compared with those in dogs with SND without prior PB exposure (SND/No PB; n=9) and with those dogs with PB‐associated hepatotoxicity without skin disease (PB/hepatotoxicity). Dogs in the SND/PB group accounted for 44% of all histologically confirmed cases of SND that were evaluated at The Ohio State University Veterinary Teaching Hospital between 1995 and 2002. Median age of dogs in the SND/PB group was 10 years, and median duration of PB therapy was 6 years. Mean alanine aminotransferase (ALT) activity was 239 U/L, and median duration of abnormally high ALT activity was 6.25 months before SND diagnosis. Plasma amino acid concentrations measured in 1 dog were severely decreased. Ultrasonographic findings of hypoechoic nodules with hyperechoic borders corresponded to pathologic findings of nodular areas of normal hepatic tissue surrounded by zones of collapsed parenchyma with vacuolated hepatocytes. Clinical, clinicopathologic, ultrasonographic, and pathologic features of SND/PB and SND/No PB were similar. PB‐associated cirrhosis and overt hepatic failure were not features of SND/PB. Different pathogenic mechanisms might induce SND in dogs. Chronic administration of PB requires further examination as a potential risk factor for the development of SND.
Hepatotoxicity Associated with CCNU (Lomustine) Chemotherapy in Dogs
Authors: Kristal Orna , Rassnick Kenneth M. , Gliatto John M. , Northrup Nicole C. , Chretin John D. , Morrison‐Collister Kirsten , Cotter Susan M. , Moore Antony S.
Published: March 2010

One hundred seventy‐nine tumor‐bearing dogs were treated with 1‐(2‐chloroethyl)‐3‐cyclohexyl‐1‐nitrosourea (CCNU) between 1995 and 2001. CCNU was given as a single dose of 50–110 mg/m2body surface area PO. Treatment interval varied, but the minimal interval between CCNU doses was 3 weeks. After treatment, 11 dogs (6.1%) developed hepatic toxicity. The median number of CCNU doses and the median total cumulative CCNU dose were significantly higher in dogs that developed hepatic toxicity (4 doses; 350 mg/m2) than in dogs without hepatic damage (3 doses; 230 mg/m2). Median duration to detection of hepatic toxicity from the last dose of CCNU was 11 weeks (range 2–49 weeks). Common biochemical abnormalities were abnormally high serum liver enzyme activities and hypoalbuminemia. Six dogs with CCNU‐associated hepatic toxicity had ascites, and 3 dogs had concurrent pleural effusion. Serum concentrations of bile acids were abnormally high in 4 of 5 dogs tested. Percutaneous ultrasound‐guided liver biopsies were performed in 10 dogs, and findings were nonspecific and chronic in nature. Seven dogs were euthanized because of progressive liver failure, and their median survival from diagnosis of liver disease was 9 weeks. Three dogs died of other causes and 1 dog of unknown cause. Although clinical signs resolved in 3 dogs, biochemical abnormalities and histopathologic lesions persisted 4 to 38 months from the time of diagnosis of liver disease. Our findings suggest that CCNU can cause delayed, cumulative dose‐related, chronic hepatotoxicity that is irreversible and can be fatal.
Clinical Efficacy and Safety of Recombinant Canine Erythropoietin in Dogs with Anemia of Chronic Renal Failure and Dogs with Recombinant Human Erythropoietin‐Induced Red Cell Aplasia
Authors: Randolph John F. , Scarlett Janet , Stokol Tracy , MacLeod James N.
Published: March 2010

The efficacy and safety of recombinant canine erythropoietin (rcEPO) therapy was evaluated in 19 dogs with anemia of chronic renal failure (group 1) and 6 dogs with chronic renal failure and recombinant human erythropoietin (rhEPO)‐induced red cell aplasia (group 2). Hematocrit (Hct) and absolute reticulocyte count (ARC) were monitored weekly for the first 8 weeks, CBC (including ARC) and serum iron profiles were evaluated monthly, and serum biochemical analyses were performed every 2 months for 6 (group 2) to 12 (group 1) months. For group 1 dogs, median Hct and ARC increased significantly during the 1st week of rcEPO treatment, and median Hct was sustained at >35% after week 5. In contrast, median Hct and ARC for group 2 did not change significantly with rcEPO treatment, even with doses greater than those used in group 1. Nevertheless, 2 (33%) of the 6 dogs in group 2 developed erythroid hyperplasia, reticulocytosis, and increases in Hct with rcEPO treatment. Although median systolic blood pressure did not change significantly in either group, 5 dogs developed systolic blood pressures a 180 mm Hg during the study. Appetite and energy level improved in most group 1 dogs with increases in Hct. Recombinant cEPO stimulated erythrocyte production in dogs with nonregenerative anemia secondary to chronic renal failure without causing the profound erythroid hypoplasia that can occur in rhEPO‐treated dogs. Unfortunately, rcEPO was not as effective in restoring erythrocyte production in dogs that had previously developed rhEPO‐induced red cell aplasia.
Airway Mucus in Recurrent Airway Obstruction– Short‐Term Response to Environmental Challenge
Authors: Gerber V. , Lindberg Å. , Berney C. , Robinson N.E.
Published: March 2010

Mucus accumulation and neutrophilic inflammation in the airways are hallmarks of heaves. Endoscopically visible mucus accumulations, however, have not been studied during exposure to dusty hay and allergens (ie, environmental challenge). We hypothesized that (1) heaves‐affected horses have increased mucus accumulation compared with controls, (2) mucus accumulations increase in heaves‐affected horses during environmental challenge, and (3) environmental challenge also induces neutrophilic inflammation and mucus accumulation in control horses. Mucus accumulation was graded endoscopically (mucus grades [MGs] 1–5), and airway inflammation was evaluated by bronchoalveolar lavage fluid (BALF) cytology before (0 hours) and during (6, 24, 48 hours) environmental challenge. Large amounts of mucus (MG 4–5) were specific for heaves‐affected horses in this study. Variation among controls was considerable, however, and intermediate grades (MG 2–3) were nonspecific, showing complete overlap between the 2 groups. Median mucus accumulations (25th, 75th percentiles) increased in heaves‐affected horses from MG 2.5 (1.5, 3.5) at baseline to MG 3.5 (2.0, 4.0), 4.0 (3.0, 4.0), and 4.0 (4.0, 4.0) at 6, 24, and 48 hours, respectively. MG values did not increase in controls–overall MG 1.0 (1.0, 2.0)–even though controls also showed a moderate increase of BALF neutro‐phils. Mucus accumulations before and especially after exposure to dust and allergens are increased in heaves‐affected horses compared with controls. Healthy controls show considerable variability in mucus accumulation but, despite an influx of neutrophils into the airways, no increase of mucus accumulation after exposure to hay dust.
The Effects of Oral Magnesium Hydroxide Administration on Rumen Fluid in Cattle
Authors: Smith Geoffrey W. , Correa Maria T.
Published: March 2010

This study was conducted to determine the effects of oral magnesium hydroxide administration on rumen fluid in cattle. Six lactating Holstein cows (4–7 years of age) with rumen fistulas were studied. Cattle were randomly assigned to receive boluses of magnesium hydroxide (162 g) or a powdered form (450 g dissolved in 3.5 L of water) PO daily for 3 days. Analysis of rumen fluid, blood gas tensions, and pH and measurement of serum magnesium concentrations were conducted daily. The study was discontinued after 72 hours, or sooner if rumen pH exceeded 8.0. After at least 3 weeks, the study was repeated with each cow receiving the other form of magnesium hydroxide (powder or bolus). Compared with baseline rumen pH (mean ± SD: 6.22 ± 0.28), magnesium hydroxide boluses caused a significant increase(P< .05) in rumen pH after 48 (7.27 ± 0.11) and 72 (8.01 ± 0.16) hours of administration, whereas the powdered form caused a significant increase(P< .05) in rumen pH after 24 (7.54 ± 0.19) and 48 (8.43 ± 0.22) hours of administration. Both the powdered and bolus forms of magnesium hydroxide decreased rumen protozoal numbers and increased methylene blue reduction times compared with baseline values. There was no change in blood pH, bicarbonate, or base excess values. Serum magnesium concentrations were significantly increased(P< .05) in cows that received the magnesium hydroxide powder. The results of this study indicate that magnesium hydroxide has a potent alkalinizing effect on rumen pH and significantly decreases rumen microbial activity.
Evaluation of a p30 Gene‐Based Real‐Time Reverse Transcriptase Polymerase Chain Reaction Assay for Detection of Feline Caliciviruses
Authors: Scansen Brian A. , Wise Annabel G. , Kruger John M. , Venta Patrick J. , Maes Roger K.
Published: March 2010

This report describes a feline calicivirus (FCV) p30 gene‐based real‐time SYBR Green I reverse transcriptase polymerase chain reaction (RT‐PCR) assay that is capable of detecting low virus concentrations and a broad range of FCV isolates. The assay consisted of a 1‐step RT‐PCR reaction with primers delineating a 126‐base‐pair (bp) region of the FCV p30 gene. Sensitivity of the RT‐PCR assay was determined to be equivalent to a FCV titer of 1.2 × 101 to 1.2 × 102 TCID50/mL. The assay was linear over a wide range of template concentrations and had a reaction efficiency of 95%. Specific FCV amplification products were detected from 51 wild‐type FCV isolates, whereas specific products were not detected from a canine calicivirus, a rabbit calicivirus, and a bovine calicivirus. The primers used in this study amplified a large number of North American FCV isolates and further confirm the diagnostic utility of p30 gene‐based real‐time RT‐PCR for detection of FCV.
Physiologic Responses in Healthy Labrador Retrievers during Field Trial Training and Competition
Authors: Steiss J. , Ahmad H.A. , Cooper P. , Ledford C.
Published: March 2010

Ten healthy Labrador Retrievers (4 females and 6 males aged 3–6.5 years [mean, 4.5 years]) training with a professional trainer were studied. The dogs were in training during the entire study. Dogs were monitored within 5 minutes after retrieving birds on land and in water on 2 consecutive days during training and on 2 consecutive days at the Atlanta Retriever Club Fall Field Trial. Baseline samples were taken in the morning on a separate day before the dogs were loaded onto a truck. Venous samples were analyzed with a portable blood analyzer. Measurements included hematocrit, sodium, potassium, chloride, blood urea nitrogen (BUN), glucose, lactate, blood pH, PCO2, PO2, HCO3, and TCO2plus rectal temperature, pulse rate, and respiratory rate. Ambient temperatures were recorded. Distances and times were estimated. Compared to baseline, significant increases occurred in rectal temperature, pulse rate, respiratory rate, chloride, lactate, and pH postexercise (P< .05); sodium, potassium, BUN, PCO2, and TCO2were significantly decreased postexercise. Blood pH was markedly higher after retrieves on land than after retrieves in water. Estimated mean speeds were 11.4 mph (18.3 km/h) during a triple retrieve on land and 5.6 mph (9.0 km/h) during a retrieve in water. Maximal ambient temperatures were 84–86oF (29–30oC). In summary, Labrador Retrievers training with a professional trainer had evidence of hyperthermia, respiratory alkalosis, hypocapnia, and mild metabolic acidosis monitored within 5 minutes postexercise during training and field trial competition when maximal ambient temperatures were 85oF (29oC). The results provide a baseline against which physiologic responses of dogs with poor performance can be compared.
High Urinary Corticoid/Creatinine Ratios in Cats with Hyperthyroidism
Authors: de Lange Mabet S. , Galac Sara , Trip Maartje R.J. , Kooistra Hans S.
Published: March 2010

Measurement of the urinary corticoid: creatinine (C: C) ratio provides an assessment of cortisol secretion over a period of time. Therefore, this test is a very sensitive measure of adrenocortical function. The stress of the diagnostic procedure and nonadrenal disease may increase the urinary C: C ratio. In addition, diseases such as hyperthyroidism may influence the metabolic clearance of cortisol. To evaluate the effect of thyroid hormone excess, urinary C: C ratios were measured in 32 cats with hyperthyroidism and 45 healthy household cats. In 7 cats, urinary C: C ratios were measured both before and after treatment for hyperthyroidism. With data from the healthy cats, the reference range for the urinary C:C ratio was determined to be 8.0 to 42.0 × 10‐6. The urinary C:C ratios in the cats with hyperthyroidism (median, 37.5 × 10‐6; range, 5.9–169.5 × 10‐6) were significantly (P =.001) higher than those in the healthy cats (median, 16 × 10‐6; range, 4.8–52.5 × 10‐6). In 15 cats with hyperthyroidism, the urinary C: C ratios exceeded the upper limit of the reference range. Treatment for hyperthyroidism led to a marked decrease in urinary C: C ratios. The results of this study demonstrate that the urinary C: C ratio may be abnormally high in cats with hyperthyroidism, probably because of increased metabolic clearance of cortisol and activation of the pituitary‐adrenocortical axis by disease. Although the clinical features of hyperthyroidism and hyperadrenocorticism in cats are different, hyperthyroidism should be ruled out when cats are suspected of hyperadrenocorticism on the basis of abnormally high urinary C: C ratios.
51Cr‐EDTA Absorption Blood Test: An Easy Method for Assessing Small Intestinal Permeability in Dogs
Authors: Frias Rafael , Sankari Satu , Westermarck Elias
Published: March 2010

The51Cr‐EDTA test is a valuable clinical tool for screening intestinal diseases in dogs. The test is performed by calculating the percentage of recovery from urine of a PO‐ingested dose of51Cr‐EDTA after 6 or 24 hours. Careful urine collection is a practical limitation of this test in dogs, and our goal was to develop a simpler test that measures51Cr‐EDTA in blood. A51Cr‐EDTA absorption test was simultaneously performed on urine and serum 43 times in healthy Beagle Dogs. Timed blood samples were withdrawn, and urine was collected during a 6‐hour period. Percentages of the ingested dose were then calculated in urine and serum. The mean ± standard deviation (range) percentage in urine after 6 hours was 14.07 ± 8.72% (3.81‐34.18%), whereas results in serum from samples taken at 2, 3, 4, 5, and 6 hours were 0.49 ± 0.45% (0.02‐2.13%), 0.75 ± 0.52% (0.03‐1.89%), 0.82 ± 0.57% (0.13‐2.21%), 0.70 ± 0.53% (0.12‐1.99%), and 0.47 ± 0.44% (0.11‐1.79%), respectively. The results for blood specimens showed good concordance with those for urine, especially for the samples taken at 4 hours (r= 0.89). Moreover, the correlation between urine and blood was better when the sum of the percentages of the recovered analyte from various blood samples was compared with urine. The correlation coefficient when summing 4 blood samples was excellent (r= 0.97) and remained excellent when summing only 2 blood samples taken at 3 and 5 hours (r= 0.95) or at 3 and 4 hours (r= 0.94). We conclude that a serum51Cr‐EDTA test determined by summing successive blood samples provides an easier means of estimating small intestinal permeability in dogs and gives results comparable to those of the 6‐hour urine test.
Magnetic Resonance Imaging Features of Feline Intracranial Neoplasia: Retrospective Analysis of 46 Cats
Authors: Troxel Mark T. , Vite Charles H. , Massicotte Christiane , McLear Robert C. , Winkle Thomas J. Van , Glass Eric N. , Tiches Deena , Dayrell‐Hart Betsy
Published: March 2010

The purpose of this retrospective study was to determine the magnetic resonance imaging (MRI) characteristics of feline brain tumors and to determine whether these characteristics can be used to accurately predict the histologic diagnosis. MRI scans of 46 cats with histologically confirmed brain tumors were reviewed, including 33 meningiomas, 6 lymphomas, 4 gliomas, 2 olfactory neuroblastomas, and 1 pituitary tumor. MRI features including axial origin, shape, location, signal intensity, contrast enhancement, peritumoral edema, and mass effect were reviewed and characterized for each tumor type. Tumor shape, axial origin, contrast enhancement, and degree of peritumoral edema aided in the identification of tumor type. Meningiomas were always extra‐axial and were most often ovoid with marked contrast enhancement and mild peritumoral edema. Gliomas were always intra‐axial with ring enhancement and generally caused more peritumoral edema than other tumors. The brain tumor was detected on MRI in 45 (98%) cats. Two blinded independent reviewers correctly identified 82% of all of the tumor types on the basis of MRI appearance alone. Thus, MRI is an excellent diagnostic tool for the detection of brain tumors in cats, and it provides important information to aid in the diagnosis of tumor type.
Efficacy and Toxicity of a Dose‐Intensified Doxorubicin Protocol in Canine Hemangiosarcoma
Authors: Sorenmo Karin U. , Baez Jennifer L. , Clifford Craig A. , Mauldin Elizabeth , Overley Beth , Skorupski Katherine , Bachman Roxanne , Samluk Marissa , Shofer Frances
Published: March 2010

The purpose of this study was to evaluate the efficacy and toxicity of a single‐agent, dose‐intensified doxorubicin protocol in canine hemangiosarcoma (HSA). Canine HSA is a highly malignant tumor, and most affected dogs die within 6 months of diagnosis. Doxorubicin is the most, and possibly the only, effective chemotherapeutic drug for this malignancy, but it provides only moderate improvement in survival. On the basis of previous studies reporting similar survival in dogs treated with doxorubicin as a single agent and doxorubicin‐based combination chemotherapy and the concept of summation dose intensity, a dose‐intensified single‐agent doxorubicin protocol was initiated. Twenty dogs with HSA were recruited to participate in this study. Workup and staging were performed according to standard practice. Chemotherapy was initiated within 3 weeks of surgery. Doxorubicin was scheduled to be administered at 30 mg/m2IV every 2 weeks for a total of 5 treatments. The dogs were monitored for toxicity and signs of recurrence during and at regular intervals after chemotherapy. The protocol was tolerated well. No dogs were hospitalized because of adverse effects or developed clinical signs consistent with doxorubicin‐induced cardiomyopathy. There was a significant difference in survival in dogs with stage I and II HSA compared with dogs with stage III HSA, with median survival times of 257, 210, and 107 days, respectively. These results are slightly better than the historical control with respect to toxicity and efficacy but are not statistically different from what is achieved with standard treatments. There was no association between dose intensity and outcome.
Efficacy and Toxicity of Paclitaxel (Taxol) for the Treatment of Canine Malignant Tumors
Authors: Poirier V.J. , Hershey A.E. , Burgess K.E. , Phillips B. , Turek M.M. , Forrest L.J. , Beaver L. , Vail D.M.
Published: March 2010

Paclitaxel (Taxol ®) was administered to 25 dogs with histologically confirmed malignant tumors at a dosage of 165 mg/m2 IV over 3–6 hours every 3 weeks. Dogs received premedication with antihistimines and corticosteroids to reduce hypersensitivity reactions. However, 64% of the dogs still experienced allergic reactions. Six dogs (24%) had grade 3 or 4 neutropenia, 6 dogs (24%) required hospitalization and 3 dogs (12%) died of sepsis. Five dogs (20%) had a partial response (osteosarcoma [2 dogs] mammary carcinoma [2 dogs] and malignant histiocytosis [1 dog]) for a median duration of 53 days. The overall toxicity was unacceptable at the 165 mg/m2 dose. Therefore, subsequent evaluations of paclitaxel in tumor‐bearing dogs should a starting dose of 132 mg/ m2 IV every 3 weeks.
Neurologic Abnormalities and Cerebrospinal Fluid Changes in Horses Administered Fumonisin B1Intravenously
Authors: Foreman Jonathan H. , Constable Peter D. , Waggoner Amy L. , Levy Michel , Eppley R.M. , Smith Geoffrey W. , Tumbleson Mike E. , Haschek Wanda M.
Published: March 2010

The objective of this experiment was to characterize a dose‐dependent toxic effect of fumonisin B1 (FB1) and to document initial neurologic signs, clinical progression, and terminal cerebrospinal fluid (CSF) changes in horses administered FB1 IV. Seventeen healthy horses were administered 0.00 (n = 4), 0.01 (n = 3), 0.05 (n = 3), 0.10 (n = 3), or 0.20 mg (n = 4) of purified FB1 IV q24h. When neurologic abnormalities observed by a masked observer became severe, atlanto‐occipital CSF taps were performed and CSF pressure, cell count, cytology, protein, albumin and glucose concentrations, and creatine kinase activity were measured. Changes in CSF and number of days to 1st observation of neurologic abnormalities were compared between doses by ANOVA, with the level of significance set atP< .05. Control horses and low‐dose horses (0.01 mg/kg) remained neurologically normal. In higher dose FB1‐treated horses (n = 10), initial clinical signs (days 4–10) included hindlimb ataxia, delayed forelimb placing, and decreased tongue tone and movement. Hindlimb and trunkal ataxia, depression, hyperesthesia, and intermittent dementia gradually became apparent. When data from all horses with neurologic abnormalities were pooled (0.05‐0.20 mg/kg FB1), mild clinical signs (mean day 6.3) occurred significantly earlier than did more severe (mean day 8.9) clinical signs (P =.009). Neurologic horses had high CSF protein, albumin, and IgG concentrations and increased albumin quotients (P< .05). It was concluded that FB1‐induced neurologic and CSF changes in a dose‐dependent manner, with a no‐observable‐limit of 0.01 mg FB/kg IV q24h for 28 days. The neurologic and CSF changes were consistent with vasogenic cerebral edema.
Characterization of the Pharmacokinetic and Pharmacodynamic Properties of the Angiotensin‐Converting Enzyme Inhibitor, Enalapril, in Horses
Authors: Gardner Sarah Y. , Atkins Clarke E. , Sams Richard A. , Schwabenton A. Brooke , Papich Mark G.
Published: March 2010

The pharmacokinetics of enalapril (0.5 mg/kg IV) and the pharmacodynamics of enalapril (0.5 mg/kg PO) in 5 mares were investigated. After single IV dosing, concentrations of enalapril and enalaprilat, its active metabolite, were measured. Two weeks later, enalapril was administered by nasogastric tube. Potassium, creatinine, blood urea nitrogen (BUN), enalapril, and enalaprilat concentrations and angiotensin converting enzyme (ACE) activity were measured in serum. In addition, heart rate, blood pressure, digital venous blood gases, and lactate were measured. Two weeks later, enalapril was again administered by nasogastric tube. To mimic activation of the renin‐angiotensin‐aldosterone system, angiotensin I (0.5 μg/kg) was administered at fixed intervals, followed by blood‐pressure and heart‐rate measurement. The elimination half lives of enalapril and enalaprilat were 0.59 and 1.25 hours, respectively, after IV administration. After PO administration, enalapril and enalaprilat were not detectable in serum. There was a tendency(P= .0625) toward a decrease in ACE activity 45–120 minutes after enalapril administration, but ACE activity suppression was never >16%. There was a tendency(P= .0625) toward a decrease in mean arterial pressure (MAP) 6–8 hours after enalapril administration. Serum concentrations of potassium, creatinine, and BUN and digital venous blood gases and lactate concentrations did not change. In response to angiotensin I, there was a tendency(P= .0625) toward a decrease in the MAP response 4–24 hours after enalapril administration. Single‐dose enalapril at 0.5 mg/kg PO did not demonstrate significant availability, pharmacodynamic effect, or substantial suppression of ACE activity.
Comparison of Serum‐Free Thyroxine Concentrations Determined by Standard Equilibrium Dialysis, Modified Equilibrium Dialysis, and 5 Radioimmunoassays in Dogs
Authors: Schachter Sara , Nelson Richard W. , Scott‐Moncrieff Catherine , Ferguson Duncan C. , Montgomery Tracey , Feldman Edward C. , Neal Larry , Kass Philip H.
Published: March 2010

Measurement of serum‐free thyroxine (fT4) concentration provides a more accurate assessment of thyroid gland function than serum thyroxine (T4) or 3,5,3'‐triiodothyronine (T3). Techniques for measuring serum fT4concentration include standard equilibrium dialysis (SED), radioimmunoassay (RIA), and a combination of both (modified equilibrium dialysis [MED]). This study compared results of serum fT4measurements by means of SED, MED, and 5 RIAs in 30 healthy dogs, 10 dogs with hypothyroidism, and 31 euthyroid dogs with concurrent illness for which hypothyroidism was a diagnostic consideration. Serum fT4concentrations were comparable when determined by the SED and MED techniques, and mean serum fT4concentrations were significantly(P<.01) lower in dogs with hypothyroidism than in healthy dogs and euthyroid dogs with concurrent illness. Significant(P< .05) differences in fT4concentrations were identified among the 5 RIAs and among the RIAs and MED and SED. Serum fT4concentrations were consistently lower when fT4was determined by the RIAs, compared with either equilibrium dialysis technique. Serum fT4concentrations were significantly lower(P <.01) in dogs with hypothyroidism than in healthy dogs for all RIAs; were significantly lower(P <.05) in dogs with hypothyroidism than in euthyroid dogs with concurrent illness for 4 RIAs; and were significantly lower(P <.01) in euthyroid dogs with concurrent illness than in healthy dogs for 4 RIAs. RIAs had the highest number of low serum fT4concentrations in euthyroid dogs with concurrent illness. This study documented differences in test results among fT4assays, emphasizing the importance of maintaining consistency in the assay used to measure serum fT4concentrations in the clinical or research setting.