Comparison of two automated multi-channel blood cell counting systems for analysis of blood of common domestic animals

An automated, multi-channel blood cell counting system (S-Plus) was compared to a reference counting system using blood samples from 187 animals of four species. The standard red cell bath aperture current of 150 volts (V) was used during analysis of 75% of the samples. At this setting, all samples with a Mean Corpuscular Volume (MCV) greater than 50 fl had accurate erythrocyte counts. As the MCV decreased below 50 fl, the severity of false low erythrocyte counts and false high MCV values increased. The remaining 25% of samples were analyzed with the red cell bath aperture current increased to 200 V. At this setting, only 5% or less of erythrocytes from animals with normal MCV values(>36 fl)were below the erythrocyte threshold. The red cell distribution width values provided by the S-Plus indicated that equine and bovine erythrocytes have greater anisocytosis than canine and feline erythrocytes. Leukocyte counts were significantly lower on the S-Plus (p<0.01). Canine and equine samples most frequently had platelet size distribution within the S-Plus platelet counting threshold window. Electronic whole blood platelet counting appeared unsatisfactory in cats due to large platelet size and erythrocyte-platelet size overlap. Small platelet size in cattle indicated that further modifications of the red cell bath aperture current would be required to count and size platelets in this species. Following electronic modifications, this state-of-the-art system appears adaptable to hematologic profiling in most species.     

Platelet size,platelet surface-associated IgG,and reticulated platelets in dogs with immune-mediated thrombocytopenia

Abstract: Immune-mediated thrombocytopenia (IMT) is a disorder in which bound IgG on the surface of platelets results in platelet removal and alterations in mean platelet volume. Using flow cytometry, alterations in platelet size, platelet surface-associated IgG (PSAIgG), and numbers of reticulated platelets were determined in 13 dogs with primary IMT and 4 dogs with secondary IMT induced by experimental infection with Babesia gibsoni . Effects of sample age on platelet parameters also were determined, using samples from 20 dogs with normal platelet counts analyzed within 4 hours and after 24, 48, and 72 hours of storage in EDTA. No significant changes in platelet count, platelet size, or reticulated platelet percentage were observed in samples assayed within 4 and 24 hours of blood collection; whereas PSAIgG values increased 3 to 7 fold in samples stored for 24–72 hours. Using reference values for freshly collected or 24-hour-old samples, 10 of 13 (77%) dogs with primary IMT and all B gibsoni-inf ected dogs had increased PSAIgG levels. In 12 (75%) of the 16 dogs with thrombocytopenia the percentage of reticulated platelets was increased; however, absolute numbers of reticulated platelets were within reference values. Moreover, PSAIgG level and the percentage of reticulated platelets were not always increased concurrently in dogs with primary and secondary IMT. Platelet microparticles were detected in all B gibsoni-infected dogs, 8 of 13 (62%) dogs with primary IMT, and transiently in a dog that responded to immunosuppressive treatment. The results of this study indicate that sample age and time of sampling during disease affect interpretation of platelet parameters in dogs with IMT.     

Haematology of clinically normal and abnormal captive llamas and guanacoes

Blood counts of healthy juvenile and adult llamas (Lama glama) and guanacoes (L guanacoe) showed that guanacoes have higher red cell counts, haemoglobin values and packed cell volumes than llamas. In both species, the numbers of lymphocytes and platelets were higher in juveniles than in adults. By reference to the values found in normal animals, abnormal haematological variations were detected in a number of sick individuals. Neutrophilia, hyperfibrinogenaemia and a tendency to develop regenerative hypochromic anaemia were observed in animals with acute and chronic inflammatory diseases and hypochromic macrocytic anaemia occurred in animals with parasitic infections. Many individuals in which subclinical intestinal parasitic infections were suspected had relatively high eosinophil counts although their other haematological values were normal.     

Presence of anti-platelet IgM and IgG antibodies in dogs naturally infected by Leishmania infantum

Thirty-three dogs, naturally infected by Leishmania infantum, were enrolled in the study and were classified as oligo-symptomatic (n. 15) and symptomatic or markedly symptomatic (n. 18). A control group was 10 healthy dogs. A haematological profile was obtained and the dogs serum was employed to assess the presence of platelet binding IgM and IgG antibodies (PBIgM, PBIgG) using flow cytometry. FITC labelled goat anti-dog IgM or IgG were used to detect PBIgM and PBIgG. Samples with a mean fluorescence intensity (MFI) that was 100 channels higher on a log scale for more than 30% of the platelets than seen in negative control platelets from a healthy dog were considered positive for the presence of anti-platelet antibodies (PBIg). Twenty-one (63.3%) dogs revealed the presence of PBIg. Six of them were oligo-symptomatic while 15 showed moderate or severe clinical signs of illness. All the dogs with PBIg showed the presence of PBIgM, with nine animals showing both PBIgM and PBIgG. Nine of 18 symptomatic or markedly symptomatic dogs showed thrombocytopenia, while normal platelet counts were observed in all oligo-symptomatic animals. Eight of 9 thrombocytopenic animals showed the presence of PBIgM, while six of them showed PBIgG. One thrombocytopenic dog was negative for PBIg. This study is the first report documenting the presence of PBIg in natural canine leishmaniasis implying a pathogenic association between thrombocytopenia and the presence of antibody against platelet membrane.     

Morphological evaluation of canine platelets on Giemsa- and PAS-stained blood smears

The morphology of canine platelets (changes in size, shape, staining characteristics, degree of activation and clump formation, distribution of granules, appearance of vacuoles on Giemsa-stained smears) was investigated in 20 healthy control and 181 diseased dogs. In the group of the sick dogs 84 animals suffered from disorders affecting directly the haematological parameters or the haematopoietic organs such as bleeding, thymic haemorrhage, haemolytic disorders, lymphoma, immune-mediated thrombocytopenia, and other 97 dogs were affected by other diseases (hepatopathy, nephropathy, hepatic, splenic or intestinal neoplasm, skin diseases, diabetes mellitus, Cushing's syndrome, sepsis). The alterations found in platelet morphology were not specific for any disorder. The most common platelet abnormalities were polychromasia and the presence of giant platelets. These changes occurred in a high number in disorders accompanied by bleeding or haemolysis. Anisocytosis was the most frequent finding in hepatic, splenic or intestinal neoplasms and in certain endocrinopathies. Microcytosis was observed in immune-mediated thrombocytopenia, hepatic neoplasms and endocrine disorders. Extreme platelet activation was common in haemolysis, hepatopathies, neoplastic diseases and sepsis. Vacuolisation was present in thymic haemorrhage, pancreatitis, diabetes mellitus and Cushing's syndrome. A new morphologic phenomenon, i.e. a ring-like formation of granules, was described in the cytoplasm of the platelets both in healthy and diseased animals. In addition, two forms of pathologic granulation were also described for the first time in Giemsa-stained blood smears: the pseudonuclear and the spot-like formation of granules, which were observed especially in disorders affecting the blood cells. The granulation and morphological characteristics of platelets on smears stained by periodic acid-Schiff reaction (PAS) were also studied. Three localisations of granulation were observed, such as peripheral, eccentric and diffuse. The ratio of PAS-positive and -negative platelets was evaluated in several diseases. Our findings support the diagnostic value of platelet evaluation by light microscopy and help clinicians/clinical pathologists to understand why morphologic changes of thrombocytes might be expected in several diseases.     

Age related haematological changes in captive Barbary sheep (Ammotragus lervia)

Full blood counts were carried out on a number of clinically normal newborn, juvenile and adult Barbary sheep. Significant age related differences in the number and size of the red cells and in the absolute and relative numbers of neutrophils and lymphocytes were found. Fibrinogen levels and platelet counts were lowest in newborn animals. These differences could complicate the interpretation of haematological findings on sick Barbary sheep if not taken into account.     

Validation of the Sysmex XT‐2000iV hematology system for dogs,cats, and horses. I. Erythrocytes,platelets, and total leukocyte counts

Background: The Sysmex XT‐2000iV is a laser‐based, flow cytometric hematology system that has been introduced for use in large and referral veterinary laboratories. Objective: The purpose of this study was to validate the Sysmex XT‐2000iV for counting erythrocytes, reticulocytes, platelets, and total leukocytes in blood from ill dogs, cats, and horses. Methods: Blood samples from diseased animals (133 dogs, 65 cats, and 73 horses) were analyzed with the Sysmex XT‐2000iV and the CELL‐DYN 3500. Manual reticulocyte counts were done on an additional 98 canine and 14 feline samples and manual platelet counts were done on an additional 73 feline and 55 canine samples, and compared with automated Sysmex results. Results: Hemoglobin concentration, RBC counts, and total WBC counts on the Sysmex were highly correlated with those from the CELL‐DYN (r≥0.98). Systematic differences occurred for MCV and HCT. MCHC was poorly correlated in all species (r=0.33–0.67). The Sysmex impedance platelet count in dogs was highly correlated with both the impedance count from the CELL‐DYN (r=0.99) and the optical platelet count from the Sysmex (r=0.98). The Sysmex optical platelet count included large platelets, such that in samples from cats, the results agreed better with manual platelet counts than with impedance platelet counts on the Sysmex. Canine reticulocyte counts on the Sysmex correlated well (r=0.90) with manual reticulocyte counts. Feline reticulocyte counts on the Sysmex correlated well with aggregate (r=0.86) but not punctate (r=0.50) reticulocyte counts. Conclusion: The Sysmex XT‐2000iV performed as well as the CELL‐DYN on blood samples from dogs, cats, and horses with a variety of hematologic abnormalities. In addition, the Sysmex detected large platelets and provided accurate reticulocyte counts.     

The importance of manual white blood cell differential counts and platelet estimates in elephant hematology: blood film review is essential

Unique features of elephant hematology are known challenges in analytical methodology like two types of monocytes typical for members of the Order Afrotheria and platelet counts of the comparatively small elephant platelet. To investigate WBC differential and platelet data generated by an impedance-based hematology analyzer without availability of validated species-specific software for recognition of elephant WBCs and platelets, compared to manual blood film review. Blood samples preserved in ethylenediaminetetraacetic acid (EDTA) of 50 elephants (n = 35 Elephas maximus and n = 15 Loxodonta africana) were used. A Mann-Whitney test for independent samples was used to compare parameters between methods and agreement was tested using Bland-Altman bias plots. All hematological variables, including absolute numbers of heterophils, lymphocytes, monocytes, eosinophils, basophils, and platelets, were significantly different (p < 0.0001) between both methods of analysis, and there was no agreement using Bland-Altman bias plots. Manual review consistently produced higher heterophil and monocyte counts as well as platelet estimates, while the automated analyzer produced higher lymphocyte, eosinophil, and basophil counts. The hematology analyzer did not properly differentiate elephant lymphocytes and monocytes, and did not accurately count elephant platelets. These findings emphasize the importance of manual blood film review as part of elephant complete blood counts in both clinical and research settings and as a basis for the development of hematological reference intervals.     

Evaluation of a citrate-based anticoagulant with platelet inhibitory activity for feline blood cell Counts

Abstract: Aggregation of feline platelets in vitro results in difficulty assessing platelet number. A citrate-based anticoagulant containing the platelet inhibitors theophylline, adenosine, and dipyridamole (CTAD; Diatube-H, Becton Dickinson, Oxford, UK) has been developed for use in human platelet studies and heparin assays. To evaluate the efficacy of CTAD in reducing platelet aggregation in feline blood samples, aliquots of blood from 51 cats were anticoagulated with EDTA, CTAD, and for 12 samples, citrate solution. Samples preserved in CTAD had significantly higher (P ≤ .001) platelet counts, as determined by an impedance counter, hemacy-tometer, and smear estimation, than samples preserved in EDTA. In addition, subjective assessment of blood smears showed significantly fewer platelet aggregates (P<.001) in CTAD-treated samples compared with EDTA samples. Although values were similar, automated platelet counts and smear estimates of platelet number were significantly higher (P < .05) and platelet aggregation was significantly less (P < .05) in CTAD samples than in citrate samples. These results suggest that the platelet inhibitory activity of CTAD reduced feline platelet aggregation. Automated total WBC counts in CTAD samples were significantly lower (P<.001) than automated counts in EDTA samples but were similar to manual WBC counts in EDTA samples. Differences in both platelet and WBC counts between CTAD and EDTA or citrate samples were clinically relevant. Mean platelet volume and MCV were significantly lower (P< .05) in CTAD samples than in EDTA samples. No effect was seen on cell morphology or staining characteristics. The anticoagulant CTAD offers an advantage over both EDTA and citrate for feline hematologic analysis, by decreasing pseudothrombocytopenia and pseudoleukocytosis.     

Hematological changes during the course of canine babesiosis caused by large Babesia in domestic dogs in Warsaw (Poland)

In the presented study we evaluated the hematological changes in samples of blood obtained from 248 dogs naturally infected with large Babesia. The evaluation included red blood cell count, hemoglobin concentration, hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), leucocyte counts, thrombocyte counts, mean platelet volume (MPV), morphology of erythrocytes and leucogram. The most common disorders in affected dogs were thrombocytopenia and anisocytosis. The count of erythrocytes below reference values was detected in 26.2% of dogs and 31.4% of affected animals presented hematocrit below the reference values. Hemoglobin concentration below the reference values was noted in 29% of dogs, an increase of MCHC above normal values was detected in 21% of examinated dogs and MCV below normal values was recognized in 2% of dogs. 60.5% of dogs presented anisocytosis, 25% poikilocytosis, 23.8% polychromasia, 19.7% hypochromia and 4.4% erythroblastosis. Thrombocytopenia was detected in 99.5% of dogs, but only 15.3% of examined animals showed increase of MPV, which suggests a response of the bone marrow. 36.3% of dogs had neutropenia, and 21.8% presented a left shift, 14.9% had the lymphocytosis and 7.2% lymphopenia.     

Measurement of thrombopoietic activity through the quantification of megakaryocytes in bone marrow cytology and reticulated platelets

Reticulated platelets are considered as marker for bone marrow thrombopoiesis. The aim of the study was evaluate the role of reticulated platelets as markers of thrombopoiesis in dogs. Reticulated platelets analysis by flow cytometry and megakaryocyte quantification by bone marrow cytology were determined in 29 healthy adult dogs (control group), 14 dogs with thrombocytopenia without megakaryocytic hypoplasia (group A) and 14 dogs with thrombocytopenia which presented megakaryocytic hypoplasia (group B), detected by bone marrow aspiration cytology. Blood samples were collected and the platelet rich plasma was obtained for reticulated platelets quantification in flow cytometry. Megakaryocytes were quantified in aspiration cytology by two techniques in marrow particles, and correlated to reticulated platelets counts. There are no differences between megakaryocyte quantification. Although there is no correlation between reticulated platelet values and megakaryocyte in bone marrow cytology, the interpretation of reticulated platelet values can be based both on absolute or relative corrected values.     

Haematological values in mouflon (Ovis musimon): influence of age, sex, season and vitamin E status

Full blood counts, fibrinogen estimations and red cell osmotic fragility tests were carried out on a number of clinically normal captive mouflon (Ovis musimon) from various locations. Age related differences in red and white cell counts and sex related differences in red cell counts were demonstrated. There was also evidence for seasonal changes in red cell values in adult females. During this study, some mouflon were found to be deficient in vitamin E and were transferred to a vitamin E supplemented diet. Comparison of findings on vitamin E deficient and supplemented animals revealed no significant haematological differences.     

Estimation of platelet counts on feline blood smears

Blood samples were obtained from 50 cats admitted for hematologic evaluation at the Royal (Dick) School of Veterinary Studies. Manual platelet counts were done using a hemacytometer, and the average number of platelets per oil immersion field (1,000X magnification) was determined on stained blood smears. A hemacytometer count was not obtained for one sample because of a failure in erythrocyte lysing. In nine samples, obvious platelet clumps in the blood smear prevented accurate determination of the number of platelets per oil immersion field. Hemacytometer counts on these nine samples ranged from 260-587 X 10 (3) platelets/microliter, suggesting that platelet clumps on a blood smear were usually associated with adequate platelet numbers. Simple regression analysis of hemacytometer counts and the average umber of platelets per oil immersion field for the remaining 40 samples yielded correlation coefficients (r) of 0.776 on untransformed data, and 0.892 on log10-transformed data. Each platelet per oil immersion field represented a circulating platelet count of approximately 20 X 10(3)/microliter, similar to conversion factors reported for dogs and human beings. It was concluded that estimation of platelet number on stained blood smears is a simple and quick method that appears to be reliable over a wide range of platelet counts in cats.     

Comparative analysis of haematological, haemostatic, and inflammatory parameters in canine venous and arterial blood samples

The objective of the present study was to validate the use of blood collected from an indwelling arterial catheter for analysis of haematological, coagulation and inflammatory parameters in canines compared to venous blood collected directly from the jugular vein. Blood samples were collected from 11 dogs. Agreement between sampling methods was found for neutrophil and monocyte counts, prothrombin time, activated partial thromboplastin time, antithrombin, protein C, factor VIII and C-reactive protein, whereas a statistically significant difference was found for white blood cells, lymphocyte, erythrocyte and platelet counts, haemoglobin, haematocrit, fibrinogen and thrombin time (TT). In conclusion, it is necessary to be aware that results from a complete blood count obtained from canine venous and arterial blood samples may not be comparable. Values for haemostatic parameters from arterial and venous blood samples, with the exception of fibrinogen and TT, were however statistically identical.     

Haematological, serum biochemical and serological features of platypuses with and without mycotic granulomatous dermatitis

OBJECTIVE: To determine whether there are haematological, serum biochemical and serological differences between platypuses (Ornithorhynchus anatinus) with and without granulomatous dermatitis due to Mucor amphibiorum infection. An additional objective was to establish reference haematological and serum biochemical ranges for the species in Tasmania. DESIGN: A clinicopathological and serological study. ANIMALS: A total of 37 free-living adult platypuses captured from streams and dams in Northern Tasmania were used in the clinicopathological study. Twenty-seven were clinically normal and 10 had mycotic granulomatous dermatitis. A total of 22 platypuses (20 adult and 2 juvenile) were used for the serosurvey. Eighteen were captured from streams in Northern Tasmania, and four were submitted for necropsy. RESULTS: Platypuses with mycotic ulcerative dermatitis had significantly smaller packed red cell volumes, haemoglobin concentrations, lymphocyte counts, serum cholesterol and calcium concentrations, and higher serum globulin and potassium concentrations than clinically normal animals. The lymphopenia and hyperkalaemia were thought to be clinically significant. Numbers of Trypanosoma binneyi in blood smears were similar between the two groups. Diseased platypuses had higher concentrations of serum antibody against Mucor amphibiorum as determined by ELISA compared to clinically normal platypuses. CONCLUSION: Platypuses affected by mycotic granulomatous dermatitis showed haematological and serum biochemical changes when compared to clinically normal animals from the same Tasmanian sites. A serological survey may be a useful method for detecting the prevalence of exposure to Mucor amphibiorum and humoral immunity in platypus populations both in Tasmania and the mainland of Australia.     

Plateletcrit is superior to platelet count for assessing platelet status in Cavalier King Charles Spaniels

Background: Many Cavalier King Charles Spaniel (CKCS) dogs are affected by an autosomal recessive dysplasia of platelets resulting in fewer but larger platelets. The IDEXX Vet Autoread (QBC) hematology analyzer directly measures the relative volume of platelets in a blood sample (plateletcrit). We hypothesized that CKCS both with and without hereditary macrothrombocytosis would have a normal plateletcrit and that the QBC results would better identify the total circulating volume of platelets in CKSC than methods directly enumerating platelet numbers.
Objectives: The major purpose of this study was to compare the QBC platelet results with platelet counts from other automated and manual methods for evaluating platelet status in CKCS dogs.
Methods: Platelet counts were determined in fresh EDTA blood from 27 adult CKCS dogs using the QBC, Sysmex XT-2000iV (optical and impedance), CELL-DYN 3500, blood smear estimate, and manual methods. Sysmex optical platelet counts were reanalyzed following gating to determine the number and percentage of normal- and large-sized platelets in each blood sample.
Results: None of the 27 CKCS dogs had thrombocytopenia (defined as <164 × 10⁹ platelets/L) based on the QBC platelet count. Fourteen (52%) to 18 (66%) of the dogs had thrombocytopenia with other methods. The percentage of large platelets, as determined by regating the Sysmex optical platelet counts, ranged from 1% to 75%, in a gradual continuum.
Conclusions: The QBC may be the best analyzer for assessing clinically relevant thrombocytopenia in CKCS dogs, because its platelet count is based on the plateletcrit, a measurement of platelet mass.     

Thrombocytopenia and platelet activity in dogs experimentally infected with Rangelia vitalii

The aim of this study was to evaluate the platelet count, coagulation time and platelet activity in dogs experimentally infected with Rangelia vitalii during the acute phase of the disease. For this study, 12 young dogs (females) were used, separated in two groups. Group A (uninfected control) was composed by healthy dogs (n=5), and group B consisted of R. vitalii-infected animals (n=7). After being inoculated with R. vitalii-infected blood, animals were monitored by blood smear examinations, which showed intra-erythrocytic forms of the parasite five days post-inoculation (PI). Blood samples were collected on days 0, 10, 20 and 30 PI. The material collected was placed in tubes containing EDTA for quantification of platelets, citrate anticoagulant platelet aggregation, and measuring the clotting time. Right after blood collection on days 10 and 20 PI, dogs were anesthetized for collecting bone marrow samples. A significant reduction (P<0.01) of the number of platelets was observed in R. vitalii-infected blood, when compared with uninfected dogs on days 10 and 20 PI. Additionally, macro-platelets were observed only in infected dogs. Prothrombin time and activated partial thromboplastin time did not differ between infected and uninfected dogs. The megakaryocyte count increased (P<0.01) significantly in infected dogs when compared with uninfected ones on days 10 and 20 PI. Platelet aggregation decreased (P<0.01) significantly in infected dogs in comparison to the control on days 10 and 20 PI. Therefore, rangeliosis in dogs causes a severe thrombocytopenia during the acute phase of infection. This platelets reduction probably occurred due to splenic sequestration and/or immune-mediated thrombocytopenia.     

Quantitation of reticulated platelets in healthy dogs and in nonthrombocytopenic dogs with clinical disease

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.     

Hematologic characteristics of captive western barred bandicoots (Perameles bougainville) from Western Australia

BACKGROUND: The western barred bandicoot (Perameles bougainville) is an Australian marsupial species now considered endangered as a consequence of habitat destruction and predation. A recently discovered papillomatosis syndrome is hindering efforts to repopulate this species. Hematology reference intervals have been lacking for P bougainville, preventing optimal interpretation of hematology results from wart-affected and clinically normal animals. OBJECTIVES: The purpose of this study was to establish hematology reference values and describe morphologic characteristics of blood cells of healthy western barred bandicoots. METHODS: Fifty-nine whole blood samples were collected by jugular venipuncture into EDTA from 47 clinically healthy captive western barred bandicoots at 3 locations on the Western Australian mainland. A CBC was performed using an ADVIA-120 analyzer. Data were compared on the basis of geographic location, sex, age, and lactation status, and reference intervals were calculated. Blood cell morphology was evaluated using light microscopy, and transmission and scanning electron microscopy. RESULTS: Significant differences were found based on sex (RBC indices, fibrinogen), age (% polychromatophilic RBCs), and geographic location (RBC, neutrophil, and lymphocyte counts, MCHC, % polychromatophilic RBCs, fibrinogen). Combined reference intervals were calculated for hemoglobin concentration (122-165 g/L), HCT (0.36-0.49 L/L), and total WBC (2.9-14.9 x 10(9)/L), monocyte (0-0.6 x 10(9)/L), eosinophil (0-0.9 x 10(9)/L), and total plasma protein (47-63 g/L) concentrations. Leukocyte, erythrocyte, and platelet morphology were similar to those of other marsupial peramelid species. Nuclei in neutrophils, monocytes, and eosinophils occasionally had an annular configuration. CONCLUSIONS: Reference intervals and blood cell morphology obtained in this study will be useful for the evaluation of laboratory data from ill animals and assist with population health monitoring of western barred bandicoots.     

Anticoagulant-induced Alterations in Pig Platelets

Application of an anticoagulant to prevent clotting is a prerequisite for the retention of morphological integrity of platelets in blood samples. Among the anticoagulants used for the collection of blood from veterinary animals, are heparin, the oxalate salts (sodium and potassium) and di-sodium and tri-sodium citrates. In a study on the effects of anticoagulants on platelet morphology, it was noted that oxalates caused severe morphological distortion in platelets. It is hypothesized that the membranous extensions, pseudopodia and loops detected in the platelets in oxalated blood may have been triggered by the irreversible formation of calcium oxalate salts which in turn alter the intracellular electrolyte balance.