bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection of Parathyroid Hormone—Related Protein in Cats with Humoral Hypercalcemia of Malignancy
Authors: Bolliger Anne Provencher , Graham Peter A. , Richard Virgile , Rosol Thomas J. , Nachreiner Raymond F. , Refsal Kent R.
Published: March 2008

Background —Increased serum parathyroid hormone‐related peptide (PTHrP) concentration is used to diagnose humoral hypercalcemia of malignancy (HHM) in humans and animals. A commercially available assay for human PTHrP has diagnostic utility in the dog, but has not been assessed in cats.

Objectives —The goals of this study were to determine serum or plasma levels of PTHrP in a population of hypercalcemic cats and to determine whether increased PTHrP concentration was associated with malignancy. In addition, we validated immunoradiometric assays (IRMAs) for intact parathormone (iPTH) and PTHrP for use with feline samples.

Methods —A retrospective analysis of iPTH and PTHrP results from 322 hypercalcemic cats (ionized calcium concentration >1.4 mmol/L) was performed. Immunoassays for human iPTH and PTHrP (residues 1–84) were validated using standard methods, and reference intervals were calculated using values from 31 healthy adult cats. Hypercalcemic cats were classified as parathyroid‐independent (iPTH <2.3 pmol/L), equivocal (iPTH 2.3–4.6 pmol/L), or parathyroid‐dependent (iPTH >4.6 pmol/L). Seven cats with detectable or increased PTHrP concentrations were evaluated further for underlying disease. Formalin‐fixed neoplastic tissues were immunohistochemically stained using rabbit antibody to human midregion PTHrP.

Results —Assays for iPTH and PTHrP showed acceptable precision for feline samples. The reference interval for iPTH was 0.8–4.6 pmol/L and for PTHrP was <1.5 pmol/L. The majority of hypercalcemic cats (263/322, 81.7%) were parathyroid‐independent, with fewer cats in the equivocal (32/322,9.9%) and parathyroid‐dependent (27/322,8.4%) groups. In 31 (9.6%) cats, PTHrP concentration was >1.5 pmol/L (range 1.5–26.6 pmol/L). All 7 cats for which follow‐up information was available had HHM; 6 had carcinomas (4 lung carcinomas, 1 undifferentiated carcinoma, 1 thyroid carcinoma) and 1 had lymphoma. All tumors had mild to moderate positive staining for PTHrP; however, lung carcinomas from normocalcemic cats also stained positive.

Conclusions —Human IRMA for PTHrP (1–84) can be used to measure PTHrP in cats. Malignancies, particularly carcinomas, appear to secrete PTHrP and induce HHM in this species. Immunohistochemistry alone cannot predict the occurrence of HHM in cats.
Quantitation of Reticulated Platelets in Healthy Dogs and in Nonthrombocytopenic Dogs With Clinical Disease
Authors: Smith Roger , Thomas Jennifer S.
Published: March 2008

Background —Thrombocytopenia is a common disorder in dogs and development of an objective diagnostic assay to measure platelets newly released from bone marrow into the blood would provide a noninvasive way to predict megakaryocytopoiesis. Reticulated platelets are newly released platelets with increased concentrations of RNA that can be detected by flow cytometric analysis of blood stained with thiazole orange (TO).

Objectives —The goals of this study were to establish a reproducible method to quantitate reticulated platelets in dogs, to establish a reference interval for reticulated platelet percentages in healthy dogs, and to determine whether the percentage of reticulated platelets was nonspecifically increased in nonthrombocytopenic dogs with clinical disease.

Methods —Blood samples were obtained from healthy dogs and from nonthrombocytopenic dogs presented for a variety of disorders. An aliquot of whole blood was stained with TO and a phycoerythrin‐labeled monoclonal antibody to platelet CD61, then analyzed by flow cytometry.

Results —The coefficients of variation were 7.8% to 15.6% (intra‐assay precision) and 6.1% to 19.5% (interassay precision). Overnight storage for 18 to 26 hours, under variable conditions, resulted in an increase in the percentage of platelets staining with TO. The reference interval for reticulated platelets in the healthy control group was 0–4.3% (0–12,095/μL). No significant differences were found in the mean percentage of reticulated platelets or absolute concentration of reticulated platelets between control and affected dogs.

Conclusions —These studies demonstrate a reliable, noninvasive diagnostic assay for measurement of reticulated platelets in whole blood and provide a baseline for assessment of the clinical utility of the assay.
Flow Cytometric Evaluation of Hemophagocytic Disorders in Canine Bone Marrow
Authors: Weiss Douglas J.
Published: March 2008

Background — Hemophagocytic macrophages in canine bone marrow are observed in malignant histiocytosis as well as benign hemophagocytic histiocytosis. Cytomorphologic evaluation alone may be inadequate to consistently differentiate between benign and malignant forms of hemophagocytic disorders.

Objective — The purpose of this study was to evaluate the ability of flow cytometry and immunophenotyping to differentiate between benign and malignant types of hemophagocytic disorders in dogs.

Methods — Blood smears and bone marrow differential cell counts were evaluated for 10 dogs with hemophagocytic disorders. Bone marrow samples were labeled with monoclonal antibodies to CD18, MCH class‐II, Thy‐1, CD14, CD3, and CD21. Using flow cytometry, forward‐angle versus side‐angle light scatter plots were analyzed and immunophenotypes were determined.

Results — Scatter plots from 3 dogs with a necropsy diagnosis of malignant histiocytosis revealed 2 atypical cell clusters. One cluster contained cells of similar size or larger than immature myeloid cells and metamyelocytes. Cells in the other cluster were highly granular, with granularity similar to or greater than that of metamyelocytes. In bone marrow from dogs with malignant histiocytosis that was labeled with anti‐CD14 antibody, macrophages represented 29–48% of nucleated cells. Seven dogs had a clinical or histopathologic diagnosis of benign hemophagocytic syndrome. Three of the dogs had normal cell distribution in scatter plots. Two dogs had 2 abnormal cell clusters: 1 within the immature myeloid and metamyelocyte gates and the other with granularity similar to or greater than that of metamyelocytes. The remaining 2 dogs had an atypical cell population, mostly within the immature myeloid gate. For dogs with benign hemophagocytic syndromes, 6–17% of cells in the bone marrow were CD14 positive.

Conclusions — The cellular distribution in scatter plots and the total number of macrophages in bone marrow may be useful in differentiating malignant histiocytosis from benign hemophagocytic syndromes in dogs.
Detection of Canine Microalbuminuria Using Semiquantitative Test Strips Designed for Use with Human Urine
Authors: Pressler Barrak M. , Vaden Shelly L. , Jensen Wayne A. , Simpson Dan
Published: March 2008

Background — Commercial testing for microalbuminuria in human urine is often performed with point‐of‐care semiquantitative test strips followed by quantitative testing when indicated. An ELISA that quantifies canine urine albumin concentration has been developed, but semiquantitative test strips for use in the dog are not available.

Objective — The purpose of this study was to prospectively determine the concordance of canine urine albumin concentrations measured by a commercial human test strip and by ELISA.

Methods — Urine samples were obtained from 67 dogs evaluated for a variety of clinical conditions. Dipstick urinalyses were performed on all samples; clinician discretion determined method of urine collection and performance of urine sediment examination and/or urine culture. Urine albumin concentration was determined using test strips (Clinitek Microalbumin, Bayer Corporation, Elkhart, Ind, USA), and results were compared with those obtained by ELISA.

Results — The Clinitek strips correctly determined albumin concentration in 42 of 67 (63%) urine samples tested. Concordance was lowest (48%) for dogs with microalbuminuria (10–300 μg/mL by ELISA). Clinitek strip sensitivity and specificity for correct identification of microalbuminuria were 48% and 75%, respectively. Concordance was lower in dogs with urinary tract infection or hematuria and in samples collected by catheterization. Sensitivity and specificity for correct identification of microalbuminuria after exclusion of dogs with urinary tract infection or hematuria were 59% and 83%, respectively.

Conclusion — These results suggest that the Clinitek strips lack sufficient concordance with results obtained by ELISA to be reliable screening tests for microalbuminuria in the dog. A reliable semiquantitative point‐of‐care test for canine urine albumin concentrations below those detected by standard urine dipsticks is still needed.
Application of Flow Cytometric Techniques to Veterinary Clinical Hematology
Authors: Weiss Douglas J.
Published: March 2008

Flow cytometry has emerged as a major new technology in veterinary clinical laboratories. Flow cytometers in current use include stand‐alone instruments and cytometers incorporated into hematology analyzers. Flow cytometers offer rapid and quantitative analysis of a variety of cell types based on cell size, molecular complexity, and antigenic composition. Therefore, flow cytometry complements and extends the knowledge that can be obtained by light microscopy. Stand‐alone instruments are very flexible, however, this flexibility opens the instrument to obtaining invalid or misleading results. The recent development of monoclonal antibodies specific for epitopes on blood cells of food and companion animals has greatly expanded the spectrum of tests with potential clinical application. Tests that appear to have the greatest potential for routine application include reticulocyte and reticulated platelet enumeration, detection of erythrocyte‐bound immunoglobulin, immunophenotyping of leukemias and lymphomas, and bone marrow differential cell counting. This report will briefly review the technical aspects of flow cytometry and then focus on techniques with present or potential application to the veterinary clinical laboratory.
Artifactual Changes in Equine Blood Following Storage, Detected Using the Advia 120 Hematology Analyzer
Authors: Clark Phillip , Mogg Tony D. , Tvedten Harold W. , Korcal David
Published: March 2008

Background — Delayed analysis of blood samples may be caused by restricted access to laboratories. Artifactual changes may occur in the measured analytes as a consequence of delayed analysis and may complicate interpretation of the data.

Objective — The purpose of this study was to characterize artifactual changes in equine blood, due to storage, using the Advia 120 hematology analyzer.

Methods — Samples of blood from 5 horses were analyzed using the Advia 120 soon after collection and again after 24 and 48 hours of storage at either 4°C or ambient laboratory temperature (∼24°C).

Results — Delayed analysis of equine blood samples resulted in increased numbers of normocytic hypochromic RBCs, increased numbers of macrocytic hypochromic RBCs, misclassification of granulocytes as mononuclear cells using the basophil reagent method, and pseudothrombocytosis, due to misclassification of ghost RBCs as platelets. The latter artifact was corrected by an amended version of the software. Many of the artifactual changes were identified by morphology flags.

Conclusion — Characteristic changes in cytograms produced by the Advia 120 allowed recognition of artifactual changes in stored equine blood samples. These changes were less pronounced in samples stored at 24°C than at 4°C.
Reference Values for Serum Biochemical Parameters in Free‐Ranging Harp Seals
Authors: Nordøy E. S. , Thoresen S. I.
Published: March 2008

Background — The harp seal (Phoca groenlandica) is one of the most important predators in the Northeastern Atlantic ecosystem. Establishing biochemical reference intervals is important for evaluating the health status of harp seals kept in captivity and for evaluating the effects of environmental changes on the health of populations in the wild.

Objective — The purpose of this study was to determine reference values for serum biochemical parameters in wild adult harp seals using readily available current methods.

Methods — Blood samples were obtained from 14 adult female harp seals and 9 suckling pups on the pack ice of the Greenland Sea in early March 1998. Seven seals were humanely killed on the ice by permission of the Norwegian Directory for Fisheries and in conjunction with several other research projects. The seals were sampled within 15 minutes postmortem. Remaining seals were captured alive and sampled via the extradural intravertebral vein. Serum biochemical parameters were measured using a Technicon Axon analyzer and included electrolytes (sodium, chloride, potassium, magnesium, and calcium), substrates (free fatty acids, triglycerides, fructosamine, and glucose), end products (urea and uric acid), and proteins (total protein, globulins, and albumin). Serum protein electrophoresis also was done. Data were tested for normality and reference limits were calculated as mean ±1.96 × SD. Results between groups were compared using 2‐tailed t‐tests.

Results — Serum levels of glucose and triglycerides were lower, but serum levels of urea were higher in dead animals than in animals that were captured alive. Serum levels for 7 of 17 parameters were significantly different in pups compared with adults. Separate reference intervals were calculated for adult seals and seal pups.

Conclusion — Both sampling method and age should be considered when evaluating the results of analysis of serum parameters in wild and captive harp seals.
Hematology, Morphology, Cytochemical Staining, and Ultrastructural Characteristics of Blood Cells in King Cobras (Ophiophagus hannah)
Authors: Salakij Chaleow , Salakij Jarernsak , Apibal Suntaree , Narkkong Nual‐Anong , Chanhome Lawan , Rochanapat Nirachara
Published: March 2008

Background —King cobras (Ophiophagus hannah) have been captive‐bred at Queen Saovabha Memorial Institute since 1996 to supply venom for antivenom production. Hematologic tests would be useful for evaluating the health of the snakes, however, basic hematologic data and morphology have not been described for this species.

Objective —The purpose of this study was to determine basic hematologic values and evaluate light microscopic, cytochemical, and electron microscopic characteristics of king cobra blood cells.

Methods —Blood samples from 13 wild‐caught and 15 captive‐bred king cobras were collected into EDTA from the ventral caudal vein. A CBC was done using standard methods. Significant differences between groups were determined usingt‐tests. Cytochemical stains (periodic acid‐Schiff [PAS], Sudan black B [SBB], a‐naphthyl acetate esterase [ANAE], acid phosphatase [AcP], and p‐glucuronidase [p‐glu]), and scanning and transmission electron microscopy were done using standard techniques.

Results —Eighteen snakes (64.3%) were positive forHepatozooninfection.Hepatozoonorganisms were detected nearly twice as frequently in wild‐caught (11/13) as in captive‐bred (7/15) snakes.Total WBC, azurophil, and lymphocyte counts were higher and fib‐rinogen concentration was lower inHepatozoon‐positivesnakes. Captive‐bred snakes had higher RBC values, lower azurophil, het‐erophil and punctate reticulocyte percentages, and higher lymphocyte numbers compared with wild‐caught snakes. Lymphocytes were the most commonly observed WBCs, and stained positive with PAS, ANAE, AcP, and (3–glu. Azurophil granules stained positive with SBB, PAS, and ANAE. Heterophils were the largest WBCs; their granules stained with SBB, ANAE, and (3–glu. Basophil granules stained with PAS, SBB, ANAE, and (3–glu. Thrombocytes were strongly positive with PAS. Transmission electron microscopic examination revealed organelles within all WBCs except eosinophils and revealed the gamonts ofHepatozoonsp in RBCs and azurophils.

Conclusions —These results provide comparative hematologic data and a guide for identification of blood cells in wild‐caught and captive‐bred king cobra snakes.Hepatozooninfection was relatively common, but was not associated with severe hematologic abnormalities.
Clinical Chemistry of Companion Avian Species: A Review
Authors: Harr Kendal E.
Published: March 2008

Birds have evolved alternate physiologic strategies to contend with dehydration, starvation, malnutrition, and reproduction. Basic anatomic and functional differences between birds and mammals impact clinical chemistry values and their evaluation. Interpretation of the results of standard biochemical analyses, including BUN, alanine aminotransferase, aspartate aminotransferase, creatine kinase, gamma glutamyltransferase, bilirubin, ammonia, alkaline phosphatase, cholesterol, bile acids, glucose, albumin, globulins, calcium, phosphorus, prealbumin (transthyretin), fibrinogen, iron, and ferritin, is reviewed and discussed in relation to these physiological differences. The use and interpretation of alternative analytes appropriate for avian species, such as uric acid, biliverdin, glutamate dehydrogenase, and galactose clearance, also are reviewed. Normal avian urine and appropriate use of urinalysis, an integral part of laboratory diagnosis in mammalian species that frequently is omitted from avian diagnostic protocols, is discussed.
Blood Copper Concentrations and Cuproenzyme Activities in a Colony of Cats
Authors: Fascetti Andrea J. , Rogers Quinton R. , Morris James G.
Published: March 2008

Background—There is little published information on plasma copper and whole blood copper concentrations in cats, and except for extracellular superoxide dismutase (EC SOD), we are unaware of published values for cat cuproenzyme activities.

Objective—In this study we determined plasma and whole blood copper concentrations, plasma ceruloplasmin (CP), EC SOD and diamine oxidase (DAO) activities, and erythrocyte superoxide dismutase (RBC SOD) activity in a specific pathogen‐free colony of cats. Results were evaluated for differences based on age and sex.

Methods—Blood was obtained from 20 adult cats (10 males, 10 females; >1 year of age) and 20 immature cats (10 males, 10 females; <1 year of age). Copper concentrations were determined using atomic absorption spectrophotometry. EC SOD and RBC SOD activities were determined using the pyrogallol oxidation method, and CP activity was determined by the oxidation of 0‐dianisidine dihydrochloride. DAO activity was measured using a colorimet‐ric assay. Differences among groups were analyzed using ANOVA.

Results—There were significant differences in mean plasma copper concentration, and CP and DAO activities (P=.001, .0001, and .02, respectively) among the 4 groups of cats. No age differences were identified. Male cats had significantly greater mean (± SEM) plasma copper (15.4± 0.9 umol/L versus 11.3 ± 0.6 umol/L;P= .001) concentrations, and CP (66.8 ± 2.9 U/L versus 39.7 ±2.1 U/L; P=.0001) and DAO (6.68 ±0.16 U/L versus 6.15 ±0.1 U/L;P= .03) activities compared with female cats. Males had significantly greater whole blood copper concentrations (16.16 ± 0.55 umol/L versus 13.36± 0.52 μmol/L;P= .002) than female cats.

Conclusion

Differences exist between male and female cats with respect to blood copper concentrations, and CP and DAO activities.
Fecal α1‐Proteinase Inhibitor Concentration in Dogs with Chronic Gastrointestinal Disease
Authors: Murphy K. F. , German A. J. , Ruaux C. G. , Steiner J. M. , Williams D. A. , Hall E. J.
Published: March 2008

Background:Fecal α1‐proteinase inhibitor (α1‐PI) clearance is a reliable, noninvasive marker for protein‐losing enteropathy in human beings. An assay for use in dogs has been developed and validated.

Objective:The aim of this study was to evaluate fecal α1‐PI concentration in dogs with chronic gastrointestinal disease, compared with healthy dogs, and to assess its correlation with serum albumin concentration.

Methods:Fecal samples were collected from 2 groups of dogs. Group 1 consisted of 21 clinically healthy client‐owned dogs without signs of gastrointestinal disease. Group 2 consisted of 16 dogs referred for investigation of suspected gastrointestinal disease. On the basis of gastric and duodenal biopsies, group 2 was further subdivided into dogs with normal histology (n = 9) and those with histologic abnormalities (n = 7: inflammatory bowel disease, n = 3; lymphangiectasia, n = 4). An ELISA was used to measure α1‐PI concentrations in fecal extracts.

Results:Fecal α1‐PI concentrations, expressed as μg/g of feces, were not significantly different between groups 1 and 2 as a whole. However, fecal α1‐PI concentrations (median, minimum‐maximum) were significantly higher in dogs with gastrointestinal diseases associated with histologic abnormalities (60.6 μg/g, 7.4–201.7 μg/g) compared with dogs with normal histology (3.8 μg/g, 0.7–74.0 μg/g) and control dogs (9.9 μg/g, 0.0–32.1 μg/g). There was no significant correlation between fecal α1‐PI and serum albumin concentrations in dogs with gastrointestinal disease.

Conclusions:Increased fecal α1‐PI concentration may signal the need to obtain gastrointestinal biopsies for a final diagnosis. Fecal α1‐PI concentration may be a useful test for early detection of protein‐losing enteropathy before decreases in serum albumin concentration can be detected.
Evaluation of a Commercially Available Human C‐Reactive Protein (CRP) Turbidometric Immunoassay for Determination of Canine Serum CRP Concentration
Authors: Kjelgaard‐Hansen Mads , Jensen Asger Lundorff , Kristensen Annemarie T.
Published: March 2008

Background:Serum C‐reactive protein (CRP) is an acute phase marker in dogs that is useful for the diagnosis and monitoring of inflammatory disease. Rapid, reliable, and automated assays are preferable for routine evaluation of canine serum CRP concentration.

Objective:The aim of this study was to evaluate whether canine serum CRP concentration could be measured reliably using an automated turbidometric immunoassay (TIA) designed for use with human serum.

Methods:A commercially available TIA for human serum CRP (Bayer, Newbury, UK) was used to measure canine serum CRP concentration. Cross‐reactivity of antigen was evaluated by the Ouchterlony procedure. Intra‐and interassay imprecision was investigated by multiple measurements on canine serum samples and serum pools, respectively. Assay inaccuracy was investigated by linearity under dilution and comparison of methodologies (canine CRP ELISA, Tridelta Development Ltd, Kildare, UK). Then the assay was applied to serum samples from 14 clinically healthy dogs, 11 dogs with neoplasia, 13 with infections, 8 with endocrine or metabolic diseases, and 10 with miscellaneous diseases.

Results:Cross‐reactivity between canine serum CRP and the anti‐human CRP antibody was found. Intra‐and interassay imprecision ranged from 5.2% to 10.8% and 3.0% to 10.2%, respectively. Serum CRP concentration was measured in a linear and proportional manner. There was no significant disagreement and there was linear correlation of the results in the comparison of methodologies, except for a slight proportional discrepancy at low CRP concentrations (<10 μg/mL). Dogs with infections had a significantly higher concentration of serum CRP than did all other dogs, and dogs with neoplasia had a significantly higher concentration of serum CRP than did clinically healthy dogs.

Conclusions:Canine serum CRP concentration can be measured reliably using the commercially available TIA designed for human CRP.
Biochemical Markers of Bone Metabolism in Animals: Uses and Limitations
Authors: Allen M. J.
Published: March 2008

Routine assessment of the skeleton's response to disease and injury traditionally has consisted of plain‐film radiography supplemented with advanced imaging techniques, such as computed tomography, magnetic resonance imaging, nuclear scintigraphy, and bone densitometry. Although these techniques provide increased sensitivity as compared with radiography, they still are limited by the fact that they can only document the net results of past skeletal activity. In contrast, serum and urinary biomarkers of bone formation and resorption provide near real‐time information about bone cell activity. In this review, I describe the scientific rationale behind the use of these markers in humans and detail the efforts that have been made to adapt this technology to veterinary medicine and animal research. Commercial assay kits that are applicable to different animal species are described, and the potential limitations of the technology are discussed. The goal of this review is to provide clinical pathologists and researchers with the information needed to decide whether the use of bone markers is likely to be helpful and to select the most appropriate marker (or panel of markers) to answer a particular question.
Fecal α1‐Proteinase Inhibitor Concentration in Dogs Receiving Long‐Term Nonsteroidal Anti‐Inflammatory Drug Therapy
Authors: Murphy K. F. , German A. J. , Ruaux C. G. , Steiner J. M. , Williams D. A. , Hall E. J.
Published: March 2008

Background:Fecal α1‐proteinase inhibitor (α1‐PI) clearance is a reliable, noninvasive marker for protein‐losing enteropathy (PLE) in human beings. An assay for measurement of this protein in the dog has been developed and validated and may be useful for the investigation of gastrointestinal disease in this species. Nonsteroidal anti‐inflammatory drugs (NSAIDs) frequently are administered to dogs and may have adverse effects on the gastrointestinal tract, including gastroduodenal ulceration and altered mucosal permeability. The value of fecal α1‐PI measurement in detecting unrelated gastrointestinal disease may be limited in dogs on NSAID therapy, but α1‐PI may be a useful marker for NSAID‐induced gastrointestinal damage.

Objective:The aim of this study was to evaluate the effects of long‐term administration of NSAIDs on fecal α1‐PI concentrations in dogs.

Methods:Fecal samples were collected from 2 groups of dogs: 1) 21 clinically‐healthy client‐owned dogs without signs of gastrointestinal disease and receiving no NSAIDs and 2) 7 dogs referred for investigation and treatment of orthopedic disorders; the dogs had received either meloxicam or carprofen daily for at least 30 days. Fecal α1‐PI concentration was measured by ELISA.

Results:Fecal α1‐PI concentrations, expressed as μg/g of feces, were not significantly different between groups 1 and 2 (median [range], group 1: 9.9 μg/g [0.0–32.1 μg/g]; group 2: 5.6 μg/g [1.1–32.3 μg/g];P= .81).

Conclusions:These results suggest that use of cyclooxygenase‐2‐selective NSAIDs, such as carprofen and meloxicam, does not significantly affect fecal α1‐PI measurements. However, study numbers were small, and larger prospective trials are required to assess more accurately the gastrointestinal effects of NSAIDs in dogs.
Comparison of Whole Blood and Plasma Potassium Concentrations in Dogs Using the Reflovet System
Authors: Trumel C. , Verwaerde P. , Rascol A. , Braun J. P.
Published: March 2008

Background:The Reflovet system is designed for chemical analysis of whole blood. However, plasma or serum is recommended for potassium analysis because of possible interference from RBC potassium. Because RBC potassium concentration is low in most canine erythrocytes, however, there should be little or no interference.

Objective:The objective of this study was to compare potassium results obtained in whole blood and in plasma from dogs using the Reflovet system.

Methods:Blood samples were collected from 104 dogs into lithium‐heparin tubes. The potassium concentration was measured in whole blood, and subsequently the PCV was measured. Samples were centrifuged and the potassium concentration was measured in plasma. Comparisons were made using Deming's regression and Bland‐Altman difference plots.

Results:There was very good correlation between results of potassium measurements in whole blood and plasma (r= 0.93). Potassium values were moderately lower in whole blood: Potassiumblood= 0.912 × Potassiumplasma+ 0.119. Hemolysis had a negligible effect on the results, but the difference increased with the PCV value. In more than 90% of samples, the difference between the 2 measurements was ≤ 0.3 mmol/L.

Conclusion:There is only a negligible difference in most cases between potassium values in canine plasma and whole blood using the Reflovet system.
Cerebrospinal Fluid from a Dog with Neurologic Collapse
Authors: Thompson Craig A. , Russell Karen E. , Levine Jonathan M. , Weeks Brad R.
Published: March 2008

A 3‐year‐old Staffordshire Terrier was presented to the Texas Veterinary Medical Center with a short progressive history of anorexia, weight loss, and weakness that had progressed to ataxia and collapse with empirical treatment. The dog was tetraparetic and obtunded. Results of a complete neurologic evaluation were consistent with severe, multifocal to diffuse disease involving the forebrain, spinal cord, and brainstem. Cerebrospinal fluid, obtained via cerebellomedullary cisternal puncture, was highly cellular and contained large atypical round cells with small numbers of nondegenerate neutrophils and large mononuclear cells. Rare eosinophils and small lymphocytes were noted. The atypical round cells were approximately 15–25 μm in diameter with a single nucleus set in a small amount of cytoplasm. The nuclei were typically round to slightly ovoid; however, occasional notched, lobulated, and reniform nuclei were observed. These cells were interpreted as malignant lymphocytes. Owing to a grave prognosis, the animal was euthanized and a necropsy was performed. No gross lesions were found in the central nervous system. Multiple sections of cerebellum, medulla, and spinal cord contained a diffuse neoplastic infiltrate that was predominantly meningeal with rare superficial neuropil invasion. The neoplastic cells were arranged in sheets, cords, and rosettes. Immunohistochemical staining for vimentin, pancytokeratin, CD3, CD79a, synaptophysin, S‐100, and neuronspecific enolase was negative; glial fibrillary acidic protein (GFAP) staining was equivocal. Based on histologic findings, a diagnosis of medulloblastoma was made. This case documents the rare occurrence of a canine medulloblastoma and illustrates the difficulty in distinguishing between some embryonal brain tumors and lymphoma.
Pleural Fluid from a Dog with Marked Eosinophilia
Authors: Cowgill Elizabeth , Neel Jennifer
Published: March 2008

A 12‐year‐old neutered male Shar‐Pei was presented to the North Carolina State University Veterinary Teaching Hospital cardiology service with a 2‐week history of coughing and a 2‐day history of lethargy and anorexia. Pleural effusion and a mediastinal mass were detected with thoracic radiographs. Ten mL of fluid were removed via thoracocentesis, and cytologic examination of the fluid revealed marked eosinophilic inflammation and few atypical mast cells. Mast cell neoplasia was suspected. Aspirates of the mediastinal mass, abdominal lymph nodes, and bone marrow contained similar pleomorphic mast cells and increased numbers of eosinophils. The dog was diagnosed with systemic (visceral) mastocytosis, a rare form of neoplasia in dogs, and was euthanized. These tumors carry a poor to grave prognosis and the etiology is uncertain.
Validation of a Chemiluminescent Enzyme Immunometric Assay for Plasma Adrenocorticotropic Hormone in the Dog
Authors: Scott‐Moncrieff J. Catharine , Koshko Mark A. , Brown Jennifer A. , Hill Kate , Refsal Kent R.
Published: March 2008

Background:The concentration of canine adrenocorticotropic hormone (ACTH) is usually determined by radioimmunoassay. However, chemiluminescent assay techniques have many advantages for clinical endocrine testing.

Objectives:The objectives of this study were to validate a commercially available chemiluminescent assay for determination of canine ACTH concentration and to determine whether protease inhibitors are appropriate for use in the chemiluminescent assay system.

Methods:Biological specificity was evaluated by treatment of 3 dogs with ovine corticotropin‐releasing hormone (CRH) followed by serial measurements of ACTH and by comparison with a previously validated immunoradiometric assay. All samples were collected both in the presence and absence of aprotinin, a protease inhibitor. The assay was further evaluated by measurement of intra‐assay precision, interassay precision, and recovery after dilution.

Results:Baseline ACTH concentrations ranged from 5.6 to 15.3 pg/mL, and maximum ACTH concentrations of 158 to 1240 pg/mL were observed 30–60 minutes after CRH administration. Plasma samples collected with aprotinin had significantly lower ACTH concentrations than did samples collected without aprotinin. The intra‐assay coefficients of variance (CVs) ranged from 4.1 to 8.2%, and interassay CVs ranged from 4.6 to 14.8%. Recovery after dilution with canine plasma ranged from 93.4 to 103.0% of predicted concentration; however, inadequate recovery was observed with other diluents. There was a high correlation with the immunoradiometric assay (r= .925) but a significant negative bias (‐32.9, 95% confidence interval −50.8 to −14.9).

Conclusions:This chemiluminescent assay is a valid technique for measurement of ACTH in canine plasma. ACTH concentration measured by chemiluminescence is lower than that measured by immunoradiometry. Aprotinin decreases the measured concentration of ACTH, and this effect should be taken into account when interpreting results. Diluents supplied with the kit should not be used for dilution of canine samples.
Comparative Sequences of Canine and Feline Endothelin‐1
Authors: Biondo Alexander W. , Wiedmeyer Charles E. , Sisson David D. , Solter Philip F.
Published: March 2008

Background: Endothelin‐1 (ET‐1, “mature ET‐1”) is a potent vasoconstrictor peptide that is made along with “big ET‐1” from its precursor, preproET‐1. Increased plasma concentrations of ET‐1 and big ET‐1 occur with various forms of cardiovascular disease in humans. Our laboratory is investigating plasma endothelins as diagnostic tests of cardiovascular disease in dogs and cats; however, commercial immunoassays designed specifically for use in dogs and cats are limited.

Objective: Amino acid sequences of feline and canine big ET‐1 were obtained and used to predict antibody cross‐reactivity with immunoassay test kits from other species.

Methods: Genomic DNA was extracted from peripheral blood and total RNA was extracted from canine and feline left ventricles for reverse transcription polymerase chain reaction (PCR) and PCR amplification of segments of the canine and feline preprohormone containing the big ET‐1 sequences. The derived amino acid sequences were compared with known big ET‐1 and ET‐1 sequences of several other species, including human, mouse, and rat.

Results: Feline and canine big ET‐1 had 87–97% and 89–100% homology, respectively, with that of other mammalian species. Canine ET‐1 was identical to human, mouse, and rat ET‐1. In contrast, the amino acid sequence of feline ET‐1 was unique owing to a leucine for methionine substitution at position 7.

Conclusions: It is highly likely that anti‐human and anti‐rodent ET‐1 antibodies will cross‐react with mature canine ET‐1. In contrast, antibodies to mature ET‐1 intended for use with feline tissues and antibodies to big ET‐1 in either dogs or cats may have partial or no cross‐reactivity depending on the peptide sequences used to produce the antibodies.
Hematology and Serum Chemistry Values of the European Brown Hare
Authors: Marco Ignasi , Cuenca Rafaela , Pastor Josep , Velarde Roser , Lavin Santiago
Published: March 2008

Background: Hematology and serum biochemistry values can be useful for evaluating the health of populations of captive and free‐living European brown hares (Lepus europaeus). However, current information is fragmented and incomplete.

Objective: The objective of this study was to determine normal hematology and serum chemistry values for a population of captive European brown hares and to investigate differences related to sex and age.

Methods: Routine hematology and serum chemistry values were determined for 48 captive European brown hares in Catalonia (northeastern Spain): 21 young (6 males and 15 females) and 27 adult (14 males and 13 females) hares. Blood was obtained by auricular venipuncture while animals were physically restrained. Results were expressed as the mean ± SD, and reference intervals were calculated as the mean ± 2SD.

Results: RBC count, PCV, concentrations of hemoglobin, total protein, albumin, gamma globulin, urea nitrogen, and creatinine, and alanine aminotransferase activity were significantly higher in adults than in young hares, and alkaline phosphatase activity and total bilirubin concentration were lower. Sex differences were not observed.

Conclusions: Hematology and serum chemistry results obtained in this study are considered representative for healthy captive European brown hares. A single reference interval can be used for values from male and female hares, however, age‐specific intervals are needed for some analytes.
Effects of urinary tract inflammation and sample blood contamination on urine albumin and total protein concentrations in canine urine samples
Authors: Vaden Shelly L. , Pressler Barrak M. , Lappin Michael R. , Jensen Wayne A.
Published: March 2008

Background: Urinary tract inflammation and hemorrhage are believed to be common causes of proteinuria in dogs based on results of studies that measured total urine protein concentration. A method to quantify urine albumin (UAlb) concentration in dogs recently has become available; however, the effect of inflammation on albuminuria is unknown.

Objectives: The goals of this study were to determine the effects of urinary tract inflammation, as indicated by pyuria and sample blood contamination, on UAlb concentration and on urine protein: creatinine (UPC) ratio in dogs.

Methods: Urine samples were obtained from dogs with pyuria that were presented to a veterinary teaching hospital or were part of a laboratory colony. To mimic the effects of hematuria, canine whole blood was added to a microscopically normal canine urine sample that had baseline albumin and total protein concentrations below the limits of detection. UAlb concentration was measured using a canine albumin‐specific competitive ELISA. UPC ratio was determined using routine methods.

Results: Of 70 samples with pyuria, 67% had negligible UAlb concentrations and 81% had normal UPC ratios. UAlb concentration but not UPC ratio was significantly higher (P < 0.05) in samples with concurrent hematuria or bacteriuria. When whole blood was added to normal urine, UAlb concentration did not exceed 1 mg/dL until the sample became visibly pink; the UPC did not exceed 0.4 at any dilution.

Conclusions: Many dogs with pyuria do not have albuminuria or proteinuria; however, albuminuria may be more likely in dogs with pyuria and concurrent hematuria or bacteriuria. Hematuria may not cause an increase in UAlb concentration until it becomes macroscopic and even then may not increase the UPC ratio.
Canine and feline hematology reference values for the ADVIA 120 hematology system
Authors: Moritz Andreas , Fickenscher Yvonne , Meyer Karin , Failing Klaus , Weiss Douglas J.
Published: March 2008

Background: The ADVIA 120 is a laser‐based hematology analyzer with software applications for animal species. Accurate reference values would be useful for the assessment of new hematologic parameters and for interlaboratory comparisons.

Objective: The goal of this study was to establish reference intervals for CBC results and new parameters for RBC morphology, reticulocytes, and platelets in healthy dogs and cats using the ADVIA 120 hematology system.

Methods: The ADVIA 120, with multispecies software (version 1.107‐MS), was used to analyze whole blood samples from clinically healthy dogs (n=46) and cats (n=61). Data distribution was determined and reference intervals were calculated as 2.5 to 97.5 percentiles and 25 to 75 percentiles.

Results: Most data showed Gaussian or log‐normal distribution. The numbers of RBCs falling outside the normocyticnormochromic range were slightly higher in cats than in dogs. Both dogs and cats had reticulocytes with low, medium, and high absorbance. Mean numbers of large platelets and platelet clumps were higher in cats compared with dogs.

Conclusions: Reference intervals obtained on the ADVIA 120 provide valuable baseline information for assessing new hematologic parameters and for interlaboratory comparisons. Differences compared with previously published reference values can be attributed largely to differences in methodology.
Cytologic evaluation of bone marrow in rats: indications, methods, and normal morphology
Authors: Bolliger Anne Provencher
Published: March 2008

Abstract: Bone marrow examination is an important part of the evaluation of the hematopoietic system. In pharmaceutical and toxicological research, bone marrow evaluation can help determine the potential hematotoxicity or effects of new compounds on hematopoietic cells. The rat is a common research animal, and bone marrow evaluation often is performed in this species. The goal of this review is to provide clinical pathologists and researchers with an updated overview of bone marrow evaluation in rats as well as practical guidelines for methods and microscopic evaluation. Indications for bone marrow collection in a research setting, methods of collection and smear preparation, and unique morphologic features of rat bone marrow cells are discussed. A summary of published cell differential percentages for bone marrow from healthy rats and possible explanations for discrepancies in these values also are provided.
Hematology and clinical chemistry values in pregnant Wistar Hannover rats compared with nonmated controls
Authors: Liberati Teresa A. , Sansone Sandra R. , Feuston Maureen H.
Published: March 2008

Background: The Wistar Hannover rat has been considered as an alternative animal model to the Sprague‐Dawley rat in the safety evaluation of candidate pharmaceuticals for potential reproductive and developmental toxicity. Hematology and clinical chemistry results may provide useful evidence of maternal toxicity in the absence of fetal effects.

Objective: The purpose of this study was to evaluate differences in routine laboratory values between nonmated and pregnant (near‐term) Wistar Hannover rats during a control developmental study.

Methods: One hundred fifty pregnant female Wistar Hannover rats (TacGbcWlfBR) were dosed orally once per day with distilled water from gestation days (CDs) 6 through 17. An additional 150 nonmated (nonpregnant) females used as age‐matched controls were dosed from study days (SDs) 7 through 18. Blood samples were collected on GD18 or 19 (SD 19 or 20) for routine hematology and plasma clinical chemistry tests. Reference intervals were established for pregnant and nonmated animals.

Results: On GD 18/19, pregnant rats had a lower RBC count, hemoglobin concentration, and HCT, and higher MCH, MCHC, reticulocyte percentage, and platelet, WBC, absolute reticulocyte, segmented neutrophil, lymphocyte, and monocyte counts compared with nonmated rats. Pregnant rats had lower albumin, glucose, urea, and chloride concentrations, lower creatine kinase and alkaline phosphatase activities, higher total bilirubin, cholesterol, triglyceride, calcium, phosphorus, and globulin concentrations, and higher ALT activity than nonmated rats. Serum triglyceride concentration was approximately fourfold higher in pregnant rats compared with nonmated controls.

Conclusion: Differences in hematology and chemistry values in pregnant Wistar Hannover rats are similar to those in Sprague‐Dawley rats and support use of the Wistar Hannover rat as an animal model in the assessment of maternal toxicity. Differences in laboratory values of pregnant rats should be considered when interpreting data following exposure to candidate pharmaceuticals.
Cytology of a mass on the meningeal surface of the left brain in a dog
Authors: Sharkey Leslie C. , McDonnell John J. , Alroy Joseph
Published: March 2008

Abstract: An 11‐year‐old neutered male Labrador Retriever presented to Tufts University School of Veterinary Medicine for a 2‐week history of seizures and altered behavior. Magnetic resonance imaging (MRI) revealed a homogeneously enhancing mass involving the surface of the left temporal, parietal, and occipital lobes of the brain, causing secondary hydrocephalus. Cytology samples obtained during rostrotentorial craniectomy contained abundant amorphous pink material suggestive of neuropil, scattered leukocytes, capillary fragments, large polyhedral nerve cell bodies, and other smaller cells with pale blue cytoplasm that occasionally were vacuolated and contained fine eosinophilic granules. The cytologic diagnosis was neoplasia, possibly meningioma. Ninety days after surgery the patient was euthanized after MRI results confirmed regrowth of the tumor. Histologic samples of the meningeal lesion collected at necropsy consisted of sheets and nests of loosely packed, large polygonal cells that compressed the brain parenchyma. The cytoplasm was eosinophilic and slightly granular, whereas nuclei were dense and eccentric. Neoplastic cells stained positive for S‐100 protein, periodic acid‐Schiff, and were partially diastase resistant. Vimentin staining was negative. Ubiquitin staining was light but diffusely positive. Ultrastructural features of the neoplastic cells included numerous secondary lysosomes and irregular pleomorphic nuclei. The final diagnosis was meningeal granular cell tumor. This case documents the cytologic and histologic features of an uncommon type of meningeal tumor.
Evaluation of the cytologic diagnosis of canine prostatic disorders
Authors: Powe Joshua R. , Canfield Paul J. , Martin Patricia A.
Published: March 2008

Background: Canine prostatic disease is commonly investigated using cytologic techniques, especially now that ultrasound‐guided fine needle cell aspiration (US‐ENA) is widely available. Few studies, however, have evaluated the diagnostic accuracy of prostatic cytology. Objective: The purpose of this study was to evaluate the usefulness of cytologic investigation of prostatic disease using US‐FNA and other methods in comparison with histopathologic diagnosis.

Methods: Cytologic and histopathologic specimens of prostate or paraprostatic tissue from 25 adult dogs were retrospectively evaluated. Cytologic samples were obtained by US‐FNA, prostatic massage, or direct impression smears or aspirates of tissue at surgery. Histopathologic sections were obtained from tissue collected by biopsy or at necropsy.

Results: Cytologic diagnoses were categorized as nondiagnostic (n = 2); cyst (n = 1); squamous metaplasia (n = 2); inflammation (n = 4); benign prostatic hyperplasia (BPH; n = 5); inflammation and BPH (n = 3); inflammation, BPH, and neoplasia (n = 1); inflammation and neoplasia (n = 3); and neoplasia (n = 4). Cytologic diagnoses agreed with final histologic diagnoses in 20 of the 25 cases (80%). Of those samples collected by US‐FNA, 75% were concordant. Four samples obtained by US‐FNA and 1 sample obtained by prostatic massage and wash had discordant results.

Conclusions: The results of this study suggest strong agreement between cytologic and histopathologic diagnoses for prostatic conditions. Discordance in results obtained by US‐FNA usually was the result of the pathologic process rather than a failure to obtain an appropriate sample.