An automated impedance-based in-house hematology analyzer, the PocH-100iV Diff, which provides a 3-part leukocyte differential count that includes eosinophils, recently has been introduced.
The aims of this study were to validate results from the PocH-100iV Diff for dogs and cats and evaluate the impact of the anticoagulant used and sample storage conditions.
Blood samples collected in K3EDTA from 153 cats and 150 dogs were included in the comparison study. The reference analyzer was the ADVIA 2120 hematology analyzer, and manual differential leukocyte counts and PCV were the manual reference methods.
Coefficients of variation were < 3% except for platelet counts and feline differential and eosinophil counts. Correlation between analyzers was good to excellent except for hemoglobin (HGB) concentration in dogs and RBC indices for both species. Biases were close to 0 except for MCHC and platelet counts. Correlation with manual counts was good for lymphocytes and OTHR cells (combined neutrophil and monocyte counts) and fair and poor for feline and canine eosinophil counts, respectively. Estimated sensitivity and specificity for detection of eosinophilia were, respectively, 50% and 98% for cats and 34% and 77% for dogs. A significant anticoagulant effect was seen for MCV in cats and for HCT, MCH, MCHC, and platelet, OTHR, and eosinophil counts in dogs. RBC and WBC counts, HGB concentration, and MCH were stable for 72 h. HCT, MCV, MCHC, and platelet counts were affected by sample storage (dogs > cats; 22°C > 4°C).
The PocH-100iV Diff is a suitable in-house instrument. A strength is its specific, but moderately sensitive, detection of feline eosinophils.
A 6-year-old intact female Pointer dog was presented for evaluation of acute onset of ataxia, circling, and head tilt. Neurologic assessment revealed overall decreased postural reaction, left-sided hemiparesis with incoordination, rigidity of fore- and hindlimbs, strabismus of the right eye, and bilateral horizontal nystagmus. Using magnetic resonance imaging, a mass lesion was identified in the cerebrum adjacent to the left side of the cerebellum compressing the brain stem ventrally. The mass was incompletely resected, and during surgery fine-needle aspiration and biopsy of the mass were performed. Cytologically, smears were highly cellular and contained predominantly small to medium-sized discrete round cells with high nuclear to cytoplasmic ratios and round nuclei with rare deep clefts or indentation, smooth chromatin, and indistinct nucleoli. Numerous cytoplasmic fragments were noted in the background. The primary diagnosis was lymphoma; other differential diagnoses included neuroendocrine tumor and poorly differentiated tumor of neural origin. The histologic diagnosis was lymphoma, and the lesion was presumed to be metastatic. On immunohistochemical analysis, the cells expressed neither CD3 nor CD79a. Re-examination of the histologic section revealed disorganized sheets of cells with multifocal palisading and perivascular arrangements of rosette-like structures. An expanded panel of antibodies to vimentin, cytokeratin, glial fibrillary acid protein (GFAP), neuron-specific enolase (NSE), synaptophysin (SYN), S-100, and CD45 was applied to histologic sections. Neoplastic cells were immunoreactive for vimentin, NSE, and S-100. Based on the histologic appearance and immunophenotype of the tumor, a diagnosis of primitive neuroectodermal tumor (PNET) was made. PNET, although rare in dogs, should be considered as a differential diagnosis for round cell tumors in the brain.
Primary immune-mediated hemolytic anemia (IMHA) is an important cause of morbidity and mortality in dogs. The mechanisms underlying autoimmune reactivity remain poorly understood.
The aim of this study was to identify membrane proteins of RBCs that could be antigenic in dogs with primary IMHA.
Antibodies were eluted with xylene from RBCs of 12 dogs with IMHA, 4 dogs with anemia due to causes other than IMHA, and 2 healthy dogs. Pooled RBC membrane proteins were prepared from blood of 17 healthy dogs. The eluted antibodies were then analyzed by immunoblotting for interactions with the pooled membrane proteins and autologous plasma. Bands present in the 12 dogs with IMHA but not in the 6 other dogs were considered potential autoantigens and were identified by liquid chromatography followed by tandem mass spectrometry.
RBC eluates from all 18 dogs had reactivity against band 3 protein. Antibodies to 6 additional proteins were uniquely identified in dogs with IMHA. Reactivity to calpain, complement component 3, and peroxiredoxin 2 was identified in 8, 8, and 4 of the 12 samples, respectively, from dogs with IMHA, but in none of the samples from the 6 dogs without IMHA.
Detection of universal immune reactivity against band 3 protein probably indicates recognition of senescent RBC. Proteins uniquely recognized by antibodies in dogs with IMHA are involved in oxidative stress and apoptosis (calpain), inflammation (complement), and scavenging of reactive oxygen species (peroxiredoxin 2). It remains to be determined if these proteins are important in initiating autoimmunity or if immunoglobulins targeting these proteins develop during IMHA.
β-Carotene is an important precursor of vitamin A, and is associated with bovine fertility. β-Carotene concentrations in plasma are used to optimize β-carotene supplementation in cattle, but measurement requires specialized equipment to separate plasma and extract and measure β-carotene, either using spectrophotometry or high performance liquid chromatography (HPLC).
The objective of this study was to validate a new 2-step point-of-care (POC) assay for measuring β-carotene in whole blood and plasma.
β-carotene concentrations in plasma from 166 cows were measured using HPLC and compared with results obtained using a POC assay, the iCheck-iEx-Carotene test kit. Whole blood samples from 23 of these cattle were also evaluated using the POC assay and compared with HPLC-plasma results from the same 23 animals. The POC assay includes an extraction vial (iEx Carotene) and hand-held photometer (iCheck Carotene).
Concentrations of β-carotene in plasma measured using the POC assay ranged from 0.40 to 15.84 mg/L (n = 166). No differences were observed between methods for assay of plasma (mean ± SD; n = 166): HPLC-plasma 4.23 ± 2.35 mg/L; POC-plasma 4.49 ± 2.36 mg/L. Similar good agreement was found when plasma analyzed using HPLC was compared with whole blood analyzed using the POC system (n = 23): HPLC-plasma 3.46 ± 2.12 mg/L; POC-whole blood 3.67 ± 2.29 mg/L.
Concentrations of β-carotene can be measured in blood and plasma from cattle easily and rapidly using a POC assay, and results are comparable to those obtained by the highly sophisticated HPLC method. Immediate feedback regarding β-carotene deficiency facilitates rapid and appropriate optimization of β-carotene supplementation in feed.
A 6-year-old spayed Labrador Retriever Mix dog was evaluated for a 2-week history of progressive generalized weakness and reluctance to stand. Physical examination revealed severe weakness with obtunded mentation, head tilt, bilateral nystagmus, and decreased vision. CBC findings included mild nonregenerative anemia, marked thrombocytopenia, and a few atypical mononuclear cells on the blood film. The cells were 15–30 μm in diameter and had round to oval to reniform centrally placed nuclei with stippled chromatin, prominent nucleoli, and abundant basophilic cytoplasm with numerous discrete vacuoles and, occasionally, small azurophilic granules. Similar cells were found in bone marrow. On histologic examination of tissues collected at necropsy, neoplastic cells were detected in bone marrow, hepatic sinusoids, cerebral and meningeal vessels, and in capillaries of the heart, renal interstitium, small intestinal submucosa, and muscularis, and alveolar septa. A small discrete mass in the right atrium consisted of similar neoplastic cells, and the spleen was diffusely infiltrated. Tissue distribution was suggestive of intravascular lymphoma. Neoplastic cells in tissue sections were immunoreactive for vimentin, CD18, CD45, and granzyme B and lacked immunoreactivity for cytokeratin. Neoplastic cells on bone marrow aspirate smears and blood films lacked immunoreactivity for CD3, CD79a, CD1c, CD11b, CD11c, CD11d, and E-cadherin. In the absence of immunophenotypic evidence for the neoplastic cells being derived from B-cell, T-cell, or histocytic/dendritic lineages and the lack of clonal antigen receptor gene rearrangement(s), along with positive immunoreactivity for granzyme B, a tumor of NK cells was considered likely. Based on current knowledge, this is the first report of canine intravascular lymphoma, of probable NK cell origin, with peripheral blood involvement.
An 8-year-old male neutered Pomeranian dog was presented to the Veterinary Teaching Hospital at Oregon State University for surgical treatment of hydronephrosis of the left kidney and a left cranial abdominal mass. A primary ureteral mass was found during exploratory surgery, and the mass was resected and ureteral anastomosis was performed. Cytologic evaluation of the mass revealed 3 distinct cell populations, including a large number of multinucleated giant cells, a moderate number of thin spindle-shaped cells, and cohesive clusters of transitional epithelial cells. The cytologic diagnosis was giant cell sarcoma. The diagnosis was confirmed by histologic examination, and immunohistochemical staining was performed. The spindle-shaped cells and multinucleated giant cells were both immunoreactive for vimentin and spindle-shaped cells for S-100. Tumor cells did not express wide-spectrum cytokeratin, broad-spectrum muscle actin, smooth muscle actin, sarcomeric actin, desmin, BLA36, Mac 387, synaptophysin, neuron-specific enolase, glial fibrillary acid protein, or von Willebrand factor. These findings are most consistent with an anaplastic sarcoma with giant cells. This is the first case report of a primary ureteral giant cell sarcoma in a dog.
Transport of horses may have significant impact on serum biochemical and hematologic analytes and resistance to infection.
The aim of our study was to assess the influence of transport stress on selected enzymatic antioxidants in equine blood.
The study was conducted on a group of 60 horses of different breeds and ranging in age from 4 to 10 years. Venous blood was collected immediately before loading horses onto trailers for 8 hours of transport (I), immediately after unloading them from the trailer (II), and after subsequent stall rest for 24 hours (III). Hemolysates of blood were prepared, and hemoglobin (Hb) concentration and activities of the enzymatic antioxidants glutathione reductase (GR), glutathione-S-transferase (GST), and glutathione peroxidase (GPx) were measured. Enzyme activities were expressed as units of activity per gram of hemoglobin.
There were significant decreases in activities (mean ± SD U/g Hb [minimum–maximum]) of GPx between collection times I (36 ± 14 U/g Hb [9–67 U/g Hb]) and III (30 ± 11 U/g Hb [12–51 U/g Hb]) and of GR between collection times I (54 ± 28 U/g Hb [7–117 U/g Hb]) and II (40 ± 23 U/g Hb [12–145 U/g Hb]). There was no significant difference in activities of GR between collection times I and III (50 ± 27 U/g Hb [9–116 U/g Hb]). There were no differences detected in GST activity among the 3 collection times.
Road transport has an impact on activities of the antioxidant enzymes GPx and GR, with recovery of GR activity evident by 24 hours post-transport. Decreased activity of these enzymes may be one mechanism for increased susceptibility to infections that are manifest after shipping; alternatively, decreases may indicate utilization as these enzymes work to neutralize increases in reactive oxygen species.
Most cases of canine chronic intranasal disease cannot be differentiated based on clinical examination alone, and biopsy is often required for a definitive diagnosis. Nonsurgical cytologic and histologic biopsy techniques represent desirable diagnostic approaches.
The aim of this retrospective study was to determine the diagnostic accuracy of brush cytology in differentiating non-neoplastic and neoplastic diseases in dogs with chronic intranasal disease.
Cytologic samples of lesions in dogs with chronic intranasal disease were obtained by brushing over a 12-year period. All dogs had complete physical examinations as well as radiographic, rhinoscopic, and cytologic evaluation. Histologic diagnosis, follow-up clinical information, or both were used as the gold standard, and dogs free of disease or with no progression of disease at 1 year were considered negative for neoplasia. Indicators of performance of brush cytology in detecting neoplasia were calculated and included sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio.
Samples of nasal brushings from 138 dogs were evaluated. Of 62 cases of neoplastic disease, true-positive and false-negative diagnoses were made using cytologic evaluation in 44 (71.0%) and 18 (29.0%) cases, respectively. False-negative diagnoses of neoplasia were not attributed to low cellularity, but to the presence of inflammatory cells that masked neoplastic cells. Brush cytology had a sensitivity of 0.71, specificity of 0.99, positive likelihood ratio of 53.94, negative likelihood ratio of 0.29, and diagnostic odds ratio of 188.33.
Brush cytology has good diagnostic accuracy for chronic intranasal lesions in dogs.
In dogs, the diestrus phase is considerably longer than in most domestic animals, and is characterized by high circulating progesterone concentrations that may influence clinical pathology values.
The objective of this retrospective study was to investigate differences in clinical pathology data in dogs in diestrus compared with data from dogs in all other phases of the estrous cycle.
Phase of the estrous cycle was determined by histologic evaluation of reproductive tissues from 86 control female Beagles that had participated in 23 toxicity studies. Serum biochemical, hematologic, and urinalysis values from dogs in diestrus were compared with data from dogs in all other estrous cycle phases using a 2-tailed t-test.
In Beagles in diestrus (n = 38), serum cholesterol concentrations and eosinophil counts were 35% (P < .0001) and 45.8% (P = .0035) higher, respectively, than for Beagles in all other phases of the estrous cycle (n = 48). Furthermore, Beagles in diestrus had 14% lower AST activity (P = .0011), 1% lower chloride concentration (P = .0224), 7.8% lower hemoglobin concentration (P < .0001), 7.8% lower RBC count (P < .0001), and 7.6% lower hematocrit (P < .0001) compared with female dogs in all other phases of the estrous cycle. Urine values did not differ significantly between groups.
Differences in clinical pathology values between dogs in different phases of the estrous cycle could potentially confound interpretation of data in toxicity studies, which often have small group sizes. Interpretation of clinical pathology data in female dogs should be performed with due consideration given to the phase of the estrous cycle.
A 5-year-old female spayed Shetland Sheepdog Mix dog was evaluated for a history of recent seizure activity, progressive hind limb ataxia, polyuria, and polydipsia and no history of gastrointestinal signs. Physical examination findings included conscious proprioceptive deficits, ataxia, and anterior uveitis along with a hypermature cataract in the right eye. Results of a CBC, serum biochemical profile, urinalysis, and computed tomography scan of the brain were unremarkable. Cerebrospinal fluid (CSF) analysis revealed marked eosinophilic pleocytosis and rare organisms consistent with Prototheca spp within neutrophils and macrophages. On postmortem histologic examination, mononuclear inflammation and numerous intralesional algal organisms, similar to those seen on the cytologic preparation of CSF, were found in the brain, eyes, kidneys, and heart. Abnormalities were not detected on gross and histologic examination of the gastrointestinal tract. Cultures of CSF and subdural/olfactory bulb, but not intestinal tract, yielded growth of Prototheca spp, and PCR analysis and DNA sequencing confirmed the organism as Prototheca zopfii genotype 2. We have reported a rare case of disseminated protothecosis that was diagnosed by evaluation of CSF in a dog presented with neurologic signs and no overt enteric disease. Protothecosis should be considered as a rare cause of seizures, even in the absence of obvious enteric signs, and should be included in the differential diagnosis of eosinophilic pleocytosis.
Emerging evidence suggests that aquaporin (AQP) 4 water channels play an important role in water homeostasis in the brain. These water channels are most abundant in the cell membrane of astrocytes, but are also present within ependymal cell membranes and in osmosensory areas of the hypothalamus. Water transport through AQP4 depends on concentration gradients across the membrane, but the rate of transport is determined by the capacity of astrocytes to up- and down-regulate AQP4 numbers, their location within the membrane, and the overall permeability of the channel. Other functions of brain AQP4 involve potassium uptake and release by astrocytes, migration of glial cells, glial scarring, and astrocyte-to-astrocyte cell communication. AQP water channels are involved in formation and control of edema in the brain and in multiple disease processes in the brain, such as seizures and tumors. There is abundant scientific literature on AQP4 describing its structure, function, location, and role in water homeostasis and edema in the brain. Investigation of AQP expression in the canine and feline brain should be pursued so that clinically relevant comparisons between findings in mice, rats, and people and animal patients can be made.
Hypothyroidism in dogs is often difficult to diagnose owing to nonspecific clinical signs and laboratory test results that can be mimicked by nonthyroidal illness (NTI). Thyroxine (T4) circulates in blood mainly bound to T4-binding globulin and, to a lesser degree, transthyretin (TTR) and albumin. The concentration of total T4 depends on the concentrations of these binding proteins.
We hypothesized that dogs with NTI and decreased serum total T4 concentrations would have decreased serum TTR concentrations. The objective of the study was to measure and compare serum TTR concentrations in healthy dogs, in dogs with NTI and low serum T4 concentrations, and in dogs with hypothyroidism.
Assignment of dogs to 3 groups was based on physical examination and serum concentrations of T4 and TSH (mean ± SD): for healthy dogs (n = 13), T4 was 24.8 ± 3.6 nmol/L and TSH was 0.15 ± 0.08 μg/L; for dogs with NTI and low T4 (n = 20), T4 was 3.2 ± 3.0 nmol/L and TSH was 0.18 ± 0.13 μg/L; and for hypothyroid dogs (n = 19), T4 was 5.3 ± 4.3 nmol/L and TSH was 2.33 ± 1.90 μg/L). TTR concentrations in serum were determined semiquantitatively using western blot analysis.
Serum TTR concentration (mean ± SD) was decreased in the dogs with NTI (24.8 ± 7.9 mg/L) compared with that of hypothyroid dogs (41.1 ± 21.4 mg/L, P = .0035). Differences were not found between TTR concentrations in clinically healthy dogs (33.3 ± 10.1 mg/L) and hypothyroid dogs or dogs with NTI.
Serum TTR concentrations were significantly decreased in dogs with NTI and low T4 compared with concentrations in hypothyroid dogs. Additional studies should be done to determine if TTR concentrations can discriminate between dogs with NTI and low T4 and dogs with primary hypothyroidism.
Although evaluation of biochemical analytes in blood is common in veterinary practice, studies assessing the global quality of veterinary in-clinic and reference laboratory testing have not been reported.
The aim of this study was to assess the quality of biochemical testing in veterinary laboratories using results obtained from analyses of 3 levels of assayed quality control materials over 5 days.
Quality was assessed by comparison of calculated total error with quality requirements, determination of sigma metrics, use of a quality goal index to determine factors contributing to poor performance, and agreement between in-clinic and reference laboratory mean results. The suitability of in-clinic and reference laboratory instruments for statistical quality control was determined using adaptations from the computerized program, EZRules3.
Reference laboratories were able to achieve desirable quality requirements more frequently than in-clinic laboratories. Across all 3 materials, > 50% of in-clinic analyzers achieved a sigma metric ≥ 6.0 for measurement of 2 analytes, whereas > 50% of reference laboratory analyzers achieved a sigma metric ≥ 6.0 for measurement of 6 analytes. Expanded uncertainty of measurement and ± total allowable error resulted in the highest mean percentages of analytes demonstrating agreement between in-clinic and reference laboratories. Owing to marked variation in bias and coefficient of variation between analyzers of the same and different types, the percentages of analytes suitable for statistical quality control varied widely.
These findings reflect the current state-of-the-art with regard to in-clinic and reference laboratory analyzer performance and provide a baseline for future evaluations of the quality of veterinary laboratory testing.
The effects of delayed anticoagulation and use of evacuated vacuum tubes in the collection of whole blood for nonactivated thrombelastography (TEG) are not known.
The objective of this study was to examine the effects of delayed anticoagulation and use of vacuum-assisted blood collection tubes on results of nonactivated TEG.
Twelve clinically healthy adult dogs were used in each of 3 studies. For each study, nonactivated TEG results from paired blood samples were compared. In study 1, the effect of delayed citrate anticoagulation was evaluated by collecting samples either into syringes containing citrate or into empty syringes followed by transfer to nonevacuated tubes containing citrate. In study 2, the effect of vacuum assistance in blood transfer was evaluated by collecting samples into syringes containing citrate and transferring either to nonevacuated plastic tubes or to evacuated plastic tubes. In study 3, the combined effects of delayed anticoagulation and vacuum assistance in blood transfer were evaluated by collecting samples into syringes containing citrate or into empty syringes followed by transfer to evacuated tubes containing citrate. Thrombelastographic analysis was performed in duplicate at 39°C after a 40-minute rest period.
The collection methods that delayed anticoagulation and/or used evacuated tubes yielded samples that appeared more coagulable compared with samples not exposed to delay or evacuated tubes.
Methods by which samples are collected affect results of nonactivated TEG and should be considered when establishing reference intervals, interpreting results, and publishing TEG results.
Presence of an abdominal effusion is a typical presenting sign associated with ovarian carcinoma (OC) in dogs.
The aims of this study were to describe the cytologic features of effusions associated with OC and to evaluate the diagnostic accuracy of such features for the diagnosis of OC in dogs.
Cytologic evaluations of 7 OC-associated peritoneal effusions in dogs were used to define cytomorphologic features of this neoplasm. Then, in a blinded study to evaluate the accuracy of these features in identifying OC, 2 independent board-certified clinical pathologists reviewed 82 pleural, pericardial, and abdominal effusions resulting from OC (n = 7), other neoplasms (n = 40), and non-neoplastic disorders (n = 35). The clinical pathologists were instructed to identify all samples containing papillary structures typically seen in OC and then apply the cytomorphologic criteria determined in the first part of the study to diagnose OC.
Effusions associated with OC contained blood and had moderate to high cellularity, with neoplastic cells arranged in a prominent papillary pattern in which intercellular spaces were not clearly evident. Individual cells were approximately 30 μm in diameter, with mild anisocytosis and anisokaryosis, moderate amounts of pale blue cytoplasm, and round to oval paracentral nuclei with fine chromatin and poorly distinct small nucleoli. Using these cytologic features to identify OC in the 82 effusions, sensitivity was 86% and 100% and specificity was 57% and 97% for the 2 clinical pathologists. Overall accuracies in distinguishing OC from other effusions were 98.8% and 93.9%.
Based on this preliminary study, effusion cytology from intact female dogs affected by OC appears to be useful in suggesting a diagnosis of neoplasia. The presence of cells with a prominent and uniform papillary pattern in peritoneal and pleural effusions in dogs with appropriate signalment and clinical signs should prompt a search for primary ovarian neoplasia.
Post-transfusion survival of allogeneic RBCs has been reported to be much shorter in horses than in other species. We hypothesized that post-transfusion survival of biotinylated allogeneic equine RBCs would be greater than the survival previously reported from studies using radioactive RBC-labeling techniques.
The study objective was to determine post-transfusion survival of N-hydroxysuccinimide (NHS)-biotin-labeled allogeneic equine RBCs transfused into adult horses.
Horses were adults and included 5 donors and 5 recipients. All horses were blood-typed, and donors were paired with recipients based upon blood type and crossmatch results. Donor blood was collected in a volume of 4 L into citrate phosphate dextrose adenine-1 and stored for 24 hours, labeled with NHS-biotin, and re-infused into recipients. Post-transfusion blood samples were collected at 15 minutes and at 1, 2, 3, 5, 7, 14, 21, 28, and 35 days. Biotin-labeled RBCs were detected by flow cytometry using streptavidin–phycoerythrin. Post-transfusion survival at 24 hours, lifespan, and half-life of biotinylated RBCs were determined.
Mean ± SD survival of biotinylated RBCs at 24 hours post-transfusion was 95 ± 24%; the mean lifespan of transfused allogeneic RBCs was 39 days based on calculation of a linear regression survival curve, and mean post-transfusion RBC half-life was 20 days.
Post-transfusion survival of 24-hour stored equine allogeneic RBCs was greater than previously reported but less than that observed for other companion animal species. Mechanisms for the relatively short post-transfusion lifespan of allogeneic equine RBCs remain unknown and warrant further study.
Urinary dipsticks are the most frequent method used for screening of ketones in animals, but this method has many drawbacks. In human medicine, portable meters that measure ketones in whole blood have largely replaced urinary dipsticks.
The aim of this prospective study was to validate a portable whole-blood ketone meter for use in cats.
Sixty-two cats (11 clinically healthy, 51 with diabetes mellitus) were included in the study. The concentration of β-hydroxybuyrate (β-HB) was measured in venous and capillary blood with a hand-held ketone meter (Precision Xceed; assay range 0–8 mmol/L) and compared with a spectrophotometric method. Precision, accuracy, and the effects of hematocrit and anticoagulants were evaluated.
Between-run precision using low- and high-concentration control solutions was 8.1% and 2.6%, respectively; within-run coefficient of variation determined using 12 feline blood samples was 2.8%. In the 62 cats, β-HB concentrations measured with the portable ketone meter ranged from 0–7.4 mmol/L (median 0.9 mmol/L). When β-HB concentrations measured by the portable meter were < 4.0 mmol/L there was good agreement with the reference method, but concentrations > 4.0 mmol/L were lower than those obtained by the reference method in 20 of 24 cats (83%). There was good correlation between capillary and venous measurements. Results were not affected by hematocrits from 0.17 to 0.50 L/L, but EDTA was not a suitable anticoagulant.
Measurement of β-HB concentration in peripheral or capillary blood by an easy-to-use portable ketone meter was suitable for detecting ketonemia in cats. Underestimation of β-HB concentration was observed at higher values, but results were sufficiently high to aid in diagnosing diabetic ketoacidosis.
Mycoplasma ovis is a hemoplasma parasite of sheep, goats, and reindeer; however, natural hemoplasma infection in white-tailed deer has not previously been reported. Subsequent to finding many coccoid, bacillary, and ring-shaped organisms, consistent with hemotropic mycoplasmas, on RBCs from a 72-day-old female white-tailed fawn, we sought to (1) identify the putative hemoplasma observed in blood from the fawn, (2) evaluate others in the herd for hemoplasma infection, and (3) identify clinicopathologic characteristics of hemoplasma-infected white-tailed deer. EDTA-anticoagulated whole blood was collected from the fawn and 8 apparently healthy does in the same herd. CBCs were performed on 7 nonclotted samples from the fawn and 6 does. DNA was extracted from all samples, followed by PCR amplification of bacterial (16S rDNA) and protozoal (18S rDNA) genes. The nearly complete 16S rDNA product from the fawn's sample was directly sequenced and compared with known sequences in the GenBank database. Samples from the fawn and 7 of 8 does were PCR-positive using hemoplasma-specific and M ovis-specific protocols. The fawn was PCR-negative for Anaplasma spp., Babesia spp., and Theileria spp. The 16S rDNA sequence from the fawn (GenBank accession number, FJ824847) was most closely related to M ovis (AF338268), having 98.5% sequence identity. The fawn had a mild nonregenerative anemia, a neutrophilic left-shift with toxic change, aspiration bronchopneumonia, and gastrointestinal disease. Hematologic values, including blood film evaluation, in infected does were unremarkable. The M ovis-like organism may have acted as either an opportunistic or primary pathogen in the fawn. The high occurrence of subclinical infections in the does suggests that white-tailed deer may act as wildlife reservoirs for M ovis.
Owing to the development of Greyhounds as racing sighthounds, these dogs have acquired unique physiologic adaptations that distinguish them from other breeds. Reference intervals for many analytes in retired racing Greyhounds (RRGs) differ from those of other breeds; most of the hematologic differences have also been described in other sighthounds. In this review, we provide a survey of the literature on clinical pathology of Greyhounds and other sighthounds and results of laboratory testing, including analysis of CBCs, biochemical profiles, coagulation tests, and blood gases, in RRGs at The Ohio State University. Major clinicopathologic differences in this breed include higher RBC mass, creatinine concentration, glomerular filtration rate, activities of hepatic enzymes, and concentration of cardiac troponin, as well as lower WBC, neutrophil, and platelet counts, thromboelastographic values, and concentrations of serum haptoglobin, total globulins, and T4.
Long-term corticosteroid therapy has been associated with increased risk of thrombotic disease in dogs.
The purpose of this prospective study was to use thrombelastography (TEG) and thrombin generation (TG) to detect development of a hypercoagulable state in healthy Beagle dogs receiving oral prednisone. We hypothesized that administration of corticosteroids would result in a hypercoagulable profile on TEG tracings and an increase in TG.
Six healthy adult Beagles from the University of Montreal's research colony were used to conduct a prospective longitudinal study in which all dogs received 1 mg/kg of prednisone orally once daily for 2 weeks, followed by a 6-week washout period, and then 4 mg/kg of prednisone orally once daily for 2 weeks. TEG tracings on citrated whole blood and TG measurements on frozen-thawed platelet-poor plasma were obtained before prednisone administration (baseline), at the end of the washout period, and at the end of both corticosteroid trials.
Significant differences compared with baseline values were obtained for K, α, and MA, with tracings compatible with a hypercoagulable profile following both corticosteroid trials. There was a significant increase in endogenous thrombin potential only after low-dose (1 mg/kg) prednisone.
Administration of prednisone to healthy Beagles resulted in hypercoagulability as indicated by TEG tracings, whereas the effect on TG was more variable. Further studies are needed to determine the underlying mechanisms of hypercoagulability and its clinical impact.
In human medicine, transfusion of ABO-mismatched platelets has been associated with shortened platelet survival and refractoriness to platelet transfusion because of expression of certain blood group antigens on platelets. It remains unknown if canine platelets express dog erythrocyte antigens (DEAs).
The aim of this study was to develop a flow cytometric assay for DEA 1.1 and determine whether DEA 1.1 is present on canine platelets.
Blood was collected from 172 clinically healthy dogs. Platelets and erythrocytes from each dog were tested for DEA 1.1 by flow cytometry using anti-DEA 1.1 blood-typing sera. Erythrocytes from each dog were also assessed for DEA 1.1 using a standard tube-typing test (T1) and using a second tube method (T2), if the flow cytometric and T1 results differed.
Using flow cytometry, DEA 1.1 was detected on erythrocytes of all 110 dogs shown by T1 or T2 testing to be DEA 1.1-positive. Initial results of the T1 test had a diagnostic accuracy of 93% (160 correct/172 tests). The frequency of erythrocyte DEA 1.1 positivity in previously untyped dogs (n = 118) was 56%. DEA 1.1 expression was not detected on platelets from DEA 1.1-positive dogs.
Flow cytometry was a reliable method for detection of DEA 1.1 on canine erythrocytes. The absence of DEA 1.1 on platelets from DEA 1.1-positive dogs suggests that their platelets do not express DEA 1.1 and will not induce production of anti-DEA 1.1 antibodies that might lead to platelet refractoriness or reactions to a subsequent transfusion of DEA 1.1-positive erythrocytes.
The therapeutic use of bone marrow-derived mononuclear cells (MNCs) and mesenchymal stem cells for the treatment of soft tissue and orthopedic injuries in equine patients is expanding. After collection, bone marrow must be reduced in volume and depleted of RBCs for immediate therapeutic use or to prepare cells for culture or cryopreservation and storage. The MarrowXpress (MXP) System is an automated, closed, sterile system designed to process human bone marrow samples.
The purpose of this study was to evaluate the capacity of the MXP System to process equine bone marrow to reduce volume, deplete RBCs, and enhance recovery of MNCs.
Bone marrow was collected from 47 horses into 2 60-mL syringes containing heparin and processed using the MXP System. HCT, total nucleated cell (TNC) count, and MNC count were obtained for each sample before and after processing using an Advia 120 hematology analyzer. Volume reduction, RBC depletion, and recovery of TNCs and MNCs were calculated.
For equine bone marrow samples, mean values were 73.2% for RBC depletion and 78.0% for volume reduction. TNC count before processing was 2.5 ± 1.2 × 107 and after processing was significantly higher at 7.8 ± 3.3 × 107 (P < .0001), with a recovery of 68.5 ± 24.5% (mean ± SD). MNC count before processing was 1.1 ± 0.9 × 107 and after processing was significantly higher at 3.8 ± 1.9 × 107 (P < .0001), with a recovery 73.0 ± 31.5%.
The MXP System can reliably reduce volume and deplete RBCs from aspirates of equine bone marrow aspirates. MNCs can be recovered in a reproducible and sterile manner. Further studies evaluating the effects of the MXP System on cell viability, identification of mesenchymal stem cells (MSCs), and the efficacy of MSC expansion are warranted.
Most automated hematology analyzers cannot detect canine or feline basophils. However, many veterinary laboratories continue to report basophils as part of the automated 5-part differential leukocyte count for dogs and cats.
The study objectives were to evaluate the performance of the Sysmex XT-2000iV, Advia 2120, and CELL-DYN 3500 hematology analyzers in detecting basophils using blood from dogs, cats, and rabbits with basophilia and to investigate the concurrence of basophilia and other hematologic changes, sex, and breed in dogs.
One or more of the 3 hematology analyzers was used to analyze 11 canine blood samples with prominent basophilia (≥ 5%) based on a manual differential count. In addition, samples from 2 cats and 4 rabbits with basophilia were analyzed with the Advia 2120. Leukocyte cytograms were inspected for the likely location of basophil cell clusters. In a retrospective study of canine patients, reports of hematologic results that included a manual leukocyte differential count were identified using the laboratory information system and examined for the occurrence of basophilia and other hematologic changes, sex, and breed of the dogs.
Canine basophils were not detected by the Sysmex XT-2000iV or CELL-DYN 3500 analyzers, and neither canine nor feline basophils were detected by the Advia 2120. The Advia was able to detect basophils in rabbits. On the Sysmex cytogram canine basophils were found slightly above or together with neutrophils. On the Advia Perox cytogram canine basophils were located in upper part of the lymphocyte box and in the area of large unstained cells (LUC). Dogs with marked basophilia often had concurrent eosinophilia, and basophilia may be found more frequently in Rottweiler dogs than in other breeds. In 5 dogs with marked basophilia and without eosinophilia, marked thrombocytosis and anemia were noted.
Canine basophils were not detected by these automated hematology analyzers, and careful analysis of instrument graphical displays or increased LUC (Advia) may guide the need to examine a blood smear for basophils.
Immune-mediated hemolytic anemia (IMHA) occurs in cattle; however, there are few reported cases.
The aim of this study was to investigate the prevalence of IMHA in cattle with anemia, describe the associated clinical and laboratory findings, including osmotic fragility, and identify potential causative infectious agents or drugs.
This study included 42 anemic cattle (HCT < 27.5%) comprising 31 females and 11 bulls with a mean age of 3.5 years referred to the University of Tehran Veterinary Teaching Hospital during a 10-month period. CBCs, saline osmotic fragility tests, direct Coombs’ tests, and biochemical profiles were performed, and blood smears were evaluated for spherocytosis, parasites, and microscopic agglutination. Five clinically healthy cattle were used as controls for testing osmotic fragility of RBCs.
The Coombs’ test was positive in 13/42 (30%) cattle; 5 had no evidence of concurrent disease or history of drug administration, and 8 had underlying or concurrent diseases, positivity for BLV, or exposure to drugs. The HCT (mean ± SE) of Coombs’-positive cattle (16 ± 1.7%) was significantly lower than that of Coombs’-negative animals (21 ± 0.8%). Hematologic and biochemical findings in cattle with IMHA included anisocytosis (2), polychromasia (2), basophilic stippling (2), spherocytosis (2), hyperfibrinogenemia (5), left-shifted neutrophilia (3), and hyperbilirubinemia (8). RBCs from Coombs’-positive anemic cattle were more fragile than those from Coombs’-negative anemic cattle. Four osmotically different populations of RBCs were detected in cattle with IMHA, whereas RBC populations were homogeneous in the Coombs’-negative anemic cattle and in normal cattle.
IMHA was identified in a significant proportion of anemic cattle. Idiopathic IMHA and IMHA secondary to infectious diseases and administration of certain drugs occur in cattle.
The need for breed-specific reference intervals (RIs) for Greyhounds has been identified. As Lurchers are a sighthound cross-breed, specific RIs may also be needed for these dogs. Hematologic RIs for Greyhounds and Lurchers using the Sysmex XT-2000iV hematology analyzer have not been established.
The aims of this study were to establish RIs for Greyhounds using the Sysmex XT-2000iV, to investigate whether RIs for Greyhound and nonsighthound dogs could be transferred to Lurchers, and to establish new RIs for Lurchers if transference was not possible.
Data were retrieved retrospectively from a database of blood donor dogs. Greyhound RIs were established using nonparametric methods based on a reference population of 179 dogs. For the RI transference study, 38 Lurchers were selected, following guidelines proposed by the Clinical and Laboratory Standards Institute. When transference was not appropriate, new RIs were generated using the robust method.
Greyhound RIs for the Sysmex hematology analyzer reflected known differences in this breed with a tendency toward higher RBC mass and lower WBC and platelet counts. RIs for hemoglobin concentration, HCT, MCV, MCH, MCHC, and WBC, neutrophil, lymphocyte, monocyte, and platelet counts for Greyhounds were suitable for transference to Lurchers. For RBC and eosinophil counts, new RIs were established.
Our study suggests that Lurchers share many hematologic characteristics with Greyhounds, but had higher reference limits for RBC and eosinophil counts.
Grey eosinophils (GE) reported to occur in Greyhounds, and occasionally in other breeds, have clear granules, probably due to abnormal staining properties.
The aims of this study were to investigate the frequency of GE in Greyhounds and 2 other sighthound breeds, and to assess the capacity of the ADVIA 120 and Sysmex XT-2000iV hematology analyzers to correctly identify GE.
Blood samples from 20 Greyhounds, 29 Italian Greyhounds, and 24 Whippets were analyzed using the ADVIA and Sysmex hematology analyzers, and blood smears stained with May-Grünwald Giemsa were evaluated microscopically. The frequency of samples with GE detected on smears was recorded for each breed. Manual and automated eosinophil counts were compared using a Wilcoxon signed-rank test. Agreement between methods was assessed using Passing–Bablok and Bland–Altman plots.
GE were detected in all 3 breeds: 9/20 Greyhounds (45.0%), 10/29 Italian Greyhounds (34.5%), and 5/24 Whippets (62.5%) with no significant differences in the frequency of GE among the breeds. In samples containing GE, both analyzers underestimated the percentage of eosinophils and occasionally eosinophils were not detected at all. When a novel “GE gate” was used, the percentage of eosinophils reported by the Sysmex was similar to that obtained by manual counting.
GE are found in the blood of sighthounds other than Greyhounds. Hematology analyzers may underestimate the percentage of GE, probably due to their abnormal physical or chemical features. Underestimation is slight and usually clinically insignificant, but occasionally eosinophils are completely misclassified. Using the Sysmex analyzer, a GE gate can be designed to normalize the eosinophil count.
The Sysmex pocH-100iV Diff is an impedance hematology analyzer recently introduced for point-of-care use in veterinary practices in Europe.
The purpose of this study was to validate the pocH-100iV Diff for analysis of blood samples from dogs, cats, horses, and cattle.
Fresh EDTA-blood samples from healthy and ill dogs (115), cats (94), horses (91), and cattle (78) were analyzed on the pocH-100iV Diff and the Cell-Dyn 3500. Results of the automated WBC differential counts were compared with the manual differential counts for 77 dogs, 65 cats, 40 horses, and 46 cattle. HCT were compared with PCVs obtained by microhematocrit centrifugation. Furthermore, precision, linearity, carry-over, cell aging, and clinical relevance of the pocH-100iV Diff results were assessed.
Most of the CBC results obtained by the pocH-100iV Diff correlated well with those of the Cell-Dyn 3500. Slightly low correlation was observed for canine MCV and hemoglobin concentration. Lymphocytes correlated well in horses and cattle, but less well in cats and dogs. The mixed cell population termed “OTHRS” (all granulocytes and monocytes for horses and cattle; neutrophils, monocytes, and basophils for cats and dogs) correlated well in all tested species. The instrument overestimated feline and canine eosinophils. In cats, platelet counts showed a strong negative bias.
The overall performance of the pocH-100iV Diff was excellent with the noted limitations. The automated differential count can be used as screening tool in conjunction with evaluation of a blood smear.
Corynebacterium pseudotuberculosis is the etiologic agent of caseous lymphadenitis (CLA), a disease that affects small ruminants and is responsible for economic losses, including condemnation of carcasses and damaged hides.
The goal of this study was to determine if serum haptoglobin and plasma fibrinogen concentrations and peripheral blood leukocyte counts are biologic markers of CLA in sheep.
Blood from 38 clinically healthy Santa-Inês ewes selected and segregated from a commercial flock of 2500 sheep in an area endemic for C. pseudotuberculosis was collected every 30 days for 6 months. An indirect ELISA was used to detect IgM and IgG antibodies against C. pseudotuberculosis. Serum haptoglobin concentration was measured using a hemoglobin-binding assay and plasma fibrinogen concentration by refractometry following heat precipitation. Total leukocyte counts were determined using a hemocytometer, and differential leukocyte counts were performed on smears of peripheral blood.
Twenty-one sheep were seropositive at the start of the study; 15 became seropositive during the study. Only 2 sheep were seronegative at the conclusion of the study. Haptoglobin and fibrinogen concentrations and WBC counts were not significantly different for seropositive and seronegative animals. Nine sheep, 5 that were seropositive positive at the start and 4 that became seropositive during the study period, developed abscesses in peripheral lymph nodes. There were 15 animals that became seropositive during the study, and their values did not differ significantly among the 3 phases – seronegative, acute (IgM+/IgG±), and chronic (IgM−/IgG+) – of infection. However, 11 of these sheep did not develop peripheral abscesses and had significantly higher haptoglobin concentrations and lower monocyte counts during the acute phase of the disease than did the 4 sheep that later developed abscesses.
Serum haptoglobin concentration and monocyte counts may be potential markers for progression of CLA in sheep.
Species-specific reference intervals are needed for interpretation of laboratory tests. Reference interval studies of alpacas have been limited by low numbers and use of outdated methods.
The aims of this study were to establish reference intervals for hematologic and coagulation tests in alpacas using a laser-based hematology analyzer and a mechanical clot detection coagulation analyzer, respectively; to compare results for automated and manual differential WBC and platelet counts and fibrinogen concentrations; and to examine the effect of herd and sex on hematologic tests in a population of alpacas.
Blood collected from clinically healthy female and male adult alpacas (Vicugna pacos) from 5 herds underwent full CBC analysis using an ADVIA 2120 (n = 65). Blood smears were examined for manual differential WBC counts, platelet estimates, and morphologic examination of blood cells. PCV and plasma protein and heat-precipitable fibrinogen concentration measured by refractometry were also determined. Partial thromboplastin time, prothrombin time, and clottable fibrinogen concentration were measured using a STA Compact analyzer (n = 13). Reference intervals were established using 2.5th and 97.5th percentiles for hematologic analytes and minimum and maximum values for coagulation tests. Automated and manual differential WBC counts, platelet counts, and fibrinogen concentrations were compared. Results were also evaluated for herd- and sex-associated effects.
Hematologic reference intervals for alpacas were similar to those reported previously, except for lower RBC-related results, which showed a herd bias. Correlations between automated and manual neutrophil, lymphocyte, eosinophil, and platelet counts were moderate to good, with weak to poor correlations for monocyte and basophil counts and fibrinogen concentrations. Owing to the low number of samples analyzed, reference intervals for coagulation tests should be considered estimated intervals.
Reference intervals will be useful guides for interpreting hematologic and coagulation results in alpacas, particularly when using the same instrumentation and reagents.
Frequencies of blood types A, B, and AB in domestic cats vary geographically and among breeds and have not been reported in China.
The purpose of this study was to survey the frequency of blood types in domestic cats in the Beijing area.
A total of 262 cats from the city of Beijing were blood-typed using a standard tube agglutination assay. All cats were nonpedigree domestic shorthaired and longhaired cats; purebred cats were excluded. Serum obtained from type-B cats and a lectin (Triticum vulgaris) solution served as anti-A and anti-B reagents, respectively. The presence of alloantibodies was also determined in some cats.
The frequency of blood types was 88.2% type A, 11.4% type B, and 0.4% type AB. The tube assay resulted in 3+ to 4+ agglutination reactions with either the anti-A or anti-B reagents. The 1 type AB sample showed 3+ agglutination with both anti-A and anti-B reagents; the plasma of that sample did not react with either type-A or type-B RBCs. Tested type-B cats had strong anti-A antibodies.
The frequency of blood type B in the Beijing area was relatively high and similar to that reported for other Asian countries and Australia. Blood-typing is recommended to match donors and recipients before transfusion therapy and planned matings to avoid hemolytic transfusion and neonatal isoerythrolysis reactions, respectively, due to blood-type incompatibility.
Dog erythrocyte antigen (DEA) 1.1 is the most important RBC antigen clinically, as it is highly immunogenic and causes acute hemolytic transfusion reactions (HTR) in sensitized dogs.
The aims of this study were to determine the frequency of DEA 1.1 expression in 4 Turkish dog breeds, and to estimate the potential risk of HTR when blood from a DEA 1.1-positive donor is administered to a DEA 1.1-negative recipient following sensitization by a prior mismatched transfusion.
EDTA blood samples (n = 178) were typed for DEA 1.1 using a commercial gel-column agglutination test (ID-Gel-Test Canine DEA 1.1). Probabilities of sensitization and risk of an HTR were calculated.
The frequency of positivity for DEA 1.1 among Kars (n = 59), Kangal (n = 53), Akbash (n = 50), and Catalburun (n = 16) breeds was 71.2%, 67.9%, 60.0%, and 50.0%, respectively. Potential risk for occurrence of an HTR after administration of blood from a dog of the same breed ranged from 12.5% to 14.8%, whereas HTR induced by blood of a dog from a different breed ranged from 7.2% to 25.3%.
The frequency of DEA 1.1-positive dogs among 4 Turkish breeds is high compared with that of most other breeds previously surveyed. The predicted risk of both sensitization and occurrence of DEA 1.1-related HTR following transfusion between dogs of either the same or different Turkish breeds was considerable. Although few dogs are transfused ≥4 days after the first transfusion, we recommend that (1) all donors and recipients be typed for DEA 1.1, (2) DEA 1.1-negative recipients receive only DEA 1.1-negative blood, and (3) blood be cross-matched prior to transfusing any dog ≥4 days after the first transfusion. These guidelines are also applicable to other breeds and countries.
Amniotic fluid embolism (AFE) is a rare but catastrophic complication of pregnancy characterized by severe hypotension, cardiovascular collapse, and massive consumptive coagulopathy. Several animal models of this syndrome have been proposed, but most have yielded inconclusive results.
The objective of this study was to develop a suitable animal model of AFE.
Twelve rabbits in late gestation (25 days) were used. Amniotic fluid was collected from the fetal amniotic sacs after laparotomy, and autologous fluid was injected into 6 rabbits via the left auricular vein. Six other rabbits received saline (control group). Blood pressure, platelet counts, and coagulation variables were measured at baseline and at various intervals for 60 minutes after injection. The in vitro effect of amniotic fluid on coagulation was assessed by thrombelastographic (TEG) analysis.
Injection of amniotic fluid did not reproduce clinical signs of AFE and had no effect on activated partial thromboplastin time (aPTT), prothrombin time (PT), or Factor VIII activity. However, significant thrombocytopenia was observed 5 minutes after administration of amniotic fluid and resolved by 60 minutes. In vitro addition of amniotic fluid to blood resulted in accelerated clotting on TEG tracings.
The syndrome of AFE was not reproduced in this rabbit model. However, injection of autologous amniotic fluid induced a transient and severe thrombocytopenia. Moreover, TEG analysis indicated that amniotic fluid could initiate the coagulation cascade. Other factors such as the presence of meconium in amniotic fluid may be needed to provoke more severe clinical signs.
A 16-month-old female spayed Labrador Retriever was referred to the University of Edinburgh for exercise intolerance, inappetence, and severe anemia. A CBC showed severe nonregenerative anemia and moderate numbers of atypical cells with morphologic features most consistent with megakaryoblastic origin. Similar cells were identified in a bone marrow aspirate and accounted for 23% of all nucleated cells. Atypical promegakaryocytes and megakaryocytes were also noted. Myelodysplastic syndrome affecting the megakaryocytic lineage was suspected. Cytologic examination of a fine-needle aspirate of the spleen revealed rare megakaryoblasts similar to those in blood and bone marrow. At necropsy, the bone marrow consisted of atypical megakaryoblasts and megakaryocytes that were also infiltrating spleen, liver, lymph nodes, renal perihilar tissue, and visceral adipose tissue, consistent with acute megakaryoblastic leukemia. Immunohistochemical analysis of splenic sections confirmed megakaryoblastic origin (immunoreactive for CD61 and von Willebrand factor). Some leukemic cells were also immunoreactive for myeloperoxidase (MPO). This aberrant immunophenotype suggested both megakaryocytic and granulocytic/monocytic differentiation of the leukemic cells. To our knowledge, this is the first report of MPO-positive acute megakaryoblastic leukemia in a dog.
Species-specific reference intervals for laboratory tests are required for diagnosis and management of disease. Few reports of reference intervals for biochemical analytes and protein fractions are available for alpacas.
The aims of this study were to establish reference intervals for biochemical analytes measured in both serum and plasma and in serum protein fractions, and to determine the influence of herd and sex on test results in a population of alpacas.
Blood was collected from 74 healthy male and female adult alpacas (Vicugna pacos) from 5 herds into tubes with no anticoagulant or with sodium heparin and analyzed within 4 hours. Biochemical analytes and ionized calcium were measured using a Hitachi P modular automated chemistry analyzer and an ABL-800 Flex blood-gas analyzer, respectively, and protein fractions were measured by agarose gel electrophoresis of serum. Nonparametric statistical methods were used to determine reference intervals, results obtained from serum and plasma were compared, and effects of herd and sex were examined.
Serum and plasma samples from 71 and 74 alpacas, respectively, were used to establish reference intervals for serum and plasma biochemical analytes. Intervals were similar, although clinically relevant differences between creatine kinase activity and phosphate concentration were found in individual animals. Serum proteins from 60 alpacas were analyzed by electrophoresis. There were significant herd- and sex-associated differences in some biochemical analytes and protein fractions; however, most had minimal impact on reference interval determination, with the exception of herd-associated effects on concentrations of urea nitrogen, ionized calcium, and bile acids and transferrin saturation.
Serum and plasma reference intervals are interchangeable; however, consistency of sample type is imperative when performing serial testing. Use of laboratory- and instrument-specific reference intervals is optimal; however, intervals reported here may be used as a guide for interpreting laboratory results from alpacas, especially when test methods are the same.
A captive adult crevice kelpfish, Gibbonsia montereyensis, developed a cutaneous mass, approximately 9 × 7 mm on the right side of the head in an area of nonscaled skin. Following surgical debulking, examination of both impression smears and histologic sections of the tumor revealed a predominant population of round to spindloid to polygonal cells with a moderate amount of lightly basophilic cytoplasm. The cytoplasm was filled with round, variably-sized reddish-brown granules that often obscured the nucleus. Nuclei were round to ovoid with coarsely granular chromatin. There was minimal anisocytosis and anisokaryosis. The cytoplasmic granules in histologic sections were weakly positive by the Fontana-Masson method, and staining was eliminated with melanin bleach. Immunohistochemical staining was strongly positive with a murine monoclonal antibody for melan A. As the specificity of melan A for melanophores is not clearly defined in nonmammalian species, the tumor was examined by transmission electron microscopy. Melanophores were not detected. Instead, neoplastic cells were filled with numerous intracytoplasmic organelles with triple-limiting membranes composed of concentric lamellae; these structures were most compatible with pterinosomes, which are the pigment-containing organelles of cells called xanthophores and erythrophores. As both of these organelles are ultrastructurally indistinguishable and as kelpfish skin is known to contain both xanthophores and erythrophores, a diagnosis of a mixed pigment cell tumor or chromatophoroma was made. As the tumor was grossly reddish-brown, the possibility of a neoplastic population of only erythrophores could not be excluded. Pigment cell tumors, arising from cells of the embryonic neural crest, are common in reptiles and bony fish.
A 3-year-old spayed female Labrador Retriever was presented for right prescapular lymphadenomegaly. Examination of fine-needle aspirates and impression smears of the node revealed many short hyphal structures found within macrophages and extracellularly. Hyphae were approximately 3 μm in diameter, were irregularly septate with nonparallel walls, and had a small clear halo surrounding a partially stained basophilic internal structure. Hyphae were tapered on one end and had oval to pyriform swellings of 7–10 μm on the other, resulting in a bulbous appearance. Fungal elements stained positively with Gomori methenamine silver and Periodic acid-Schiff stains. The dog was euthanized at the owner's request, and necropsy revealed marked peripheral and visceral lymphadenomegaly. Histopathologic examination of lymph nodes confirmed granulomatous lymphadenitis with many fungal hyphae. Fungal culture yielded pure cultures of organisms that failed to produce ascospores or conidia precluding morphologic identification. PCR was performed using pan-fungal primers, ITS-1 and ITS-2, to amplify the intergenic spacer regions of ribosomal RNA; the PCR product was sequenced and a BLAST search of the GenBank databases at NCBI revealed 100% identity of the organism with Talaromyces helicus, the sexual form of Penicillium helicum. Talaromyces helicus has not previously been reported to cause disease in people or animals.