A comparison study between the Siemens ADVIA 120 and manual method for the differential white blood cell count in goats.

BACKGROUND: Although widely used, the ADVIA 120 hematology analyzer has not been previously validated for determining the differential leukocyte count in goats. OBJECTIVES: The aim of this study was to compare the differential leukocyte counts provided by the ADVIA 120 (A-diff) and the manual method (M-Diff) in goats. METHODS: EDTA blood samples that were analyzed within 4 h of collection were used in the study. The following exclusion criteria were applied: inappropriately filled tubes or tubes containing clots, erroneous ADVIA peroxidase cytograms, and blood smears of poor quality. The A-Diff was compared with the M-Diff performed by two independent observers on 200 leukocytes. RESULTS: Forty samples were included after previously excluding eight samples. The correlation between the A-Diff and M-Diff was very strong for eosinophils (r = .870, p < .001) and strong for lymphocytes (r = .796, p < .001) and neutrophils (r = .730, p < .001), while no significant correlation was observed for monocytes (r = .026, p = .872). The Passing-Bablok regression analyses revealed statistically significant constant errors for neutrophils (5.83%; 95% confidence interval [CI]: 0.41%, 12.18%) and eosinophils (1.89%; 95% CI: 1.17%, 2.71%). Bland-Altman analyses showed a statistically significant negative bias for lymphocytes (-5.0%) and a statistically significant positive bias for eosinophils (2.2%). The very low basophil percentages precluded a meaningful method comparison. CONCLUSIONS: The ADVIA 120 overall demonstrated good performance for the differential WBC count in goats under the conditions of this study. Therefore, it can be considered suitable for routine hematologic screening in goats. Nonetheless, it should be emphasized that any abnormal result should be confirmed with a blood smear evaluation.

Association of platelet indices with glycemic status in diabetic dogs.

We investigated the platelet count (PLT), mean platelet volume (MPV), and plateletcrit (PCT) in dogs with type 1 diabetes mellitus (DM) compared to healthy controls, and their association with the major fraction of glycated hemoglobin (HbA1c). Blood samples from 33 clinically healthy dogs and 14 newly diagnosed diabetic dogs were included. CBCs were performed with the Advia 120; HbA1c was determined using a validated assay (Capillarys 2 flex-piercing; Sebia). Median [range] PLT and PCT were significantly higher (p = 0.040 and p = 0.010, respectively) in diabetic dogs (434 [176-987] × 109/L and 0.60 [0.26-1.22]%, respectively) compared to healthy dogs (297 [223-671] × 109/L and 0.35 [0.24-0.87]%, respectively]. Thrombocytosis was observed in 6 of 14 (43%) diabetic dogs. The median MPV was not significantly different (p = 0.114) between the diabetic (13.6 fL, 10.1-22.6 fL) and healthy dogs (11.9 fL, 8.6-19.1 fL). A significant, albeit weak, correlation was detected between HbA1c and PLT (rho = 0.298, p = 0.042) and PCT (rho = 0.340, p = 0.019), but no significant correlation was found with MPV (rho = 0.199, p = 0.180). Canine DM was associated with increased PLT and PCT, which was correlated with glycemic status. Our findings suggest dysregulated megakaryopoiesis in diabetic dogs, but this should be confirmed by large-scale studies, and the clinical implications should be investigated.

Prevalence of antinuclear antibodies and rheumatoid factor titers in dogs with arthritis secondary to leishmaniosis (Leishmania infantum).

Dogs with infectious arthritis may occasionally exhibit positive serum antinuclear antibody (ANA) and rheumatoid factor (RF) titers; however, relevant data are sparse for arthritis secondary to canine leishmaniosis (CanL) caused by Leishmania infantum. We determined the prevalence of positive serum ANA and RF titers in dogs with arthritis secondary to CanL. Blood samples from adult, client-owned dogs with purulent arthritis secondary to CanL, without any comorbidities, were collected for diagnostic purposes. Serum ANA titers were measured by immunoperoxidase test and RF titers by the Rose-Waaler latex test. Twelve of 23 dogs enrolled prospectively in our study had clinical arthritis, and 11 of 23 had subclinical arthritis. Based on LeishVet clinical staging, 7 dogs had clinical stage II disease, 11 had clinical stage III disease, and 5 had stage IV. None of the 23 dogs was seropositive for ANA; 3 of 23 were positive for RF. ANA and/or RF seropositivity, in dogs with CanL-associated arthritis, appears to be weak, if present at all. Based on our results, positive serum ANA and RF titers should not be expected in dogs with arthritis secondary to CanL.

The effect of age and sex on glycated hemoglobin in dogs.

We investigated the effect of age and sex on canine glycated hemoglobin (HbA1c) using a validated capillary electrophoresis assay. Aliquots of EDTA blood samples collected for routine health checks were used. HbA1c was measured using the Capillarys 2 flex-piercing system (Sebia). We included 58 clinically and hematologically healthy, normoglycemic dogs (29 males, 29 females), allocated to 3 age groups: young (14 dogs <1-y-old), adult (31 dogs 1-7.9-y-old), and senior (13 dogs ≥8-y-old). The mean (± SD) HbA1c was not significantly different (p = 0.428) between the age groups (young: 1.68 ± 0.54%; adult: 1.59 ± 0.41%; senior: 1.80 ± 0.57%). The HbA1c was not significantly correlated with age (rho = 0.144, p = 0.280). The median (range) HbA1c was not significantly different (p = 0.391) between male [1.7% (0.5-2.5%)] and female [1.5% (1.0-2.7%)] dogs. Age and sex do not appear to affect canine HbA1c; however, a study of geriatric dogs would be needed to fully exclude an effect of age on HbA1c.

Diagnostic and prognostic value of peripheral blood leucocyte ratios in sick cats.

The objective of this study was to assess the diagnostic and prognostic utility of feline neutrophil-to-lymphocyte (NLR) and lymphocyte-to-monocyte ratios (LMR) in a variety of underlying diseases. Five-year medical records from cats presenting to the internal medicine unit of a veterinary teaching hospital were retrospectively reviewed. Cats were considered for inclusion based on complete medical records. ADVIA 120 was used for the complete blood counts; the NLR and LMR were calculated by dividing the absolute numbers of the respective leucocytes. Two hundred and nineteen sick and 20 healthy cats were included in the study. The median NLR and LMR were significantly (P < 0.05) elevated and decreased, respectively, in cats with infectious, neoplastic and chronic kidney diseases compared to controls. Additionally, cats with neoplasia had significantly higher median NLR compared to cats with urinary tract and gastrointestinal diseases. Non-survivors had significantly higher NLR and lower LMR compared to survivors. Both ratios had suboptimal prognostic performance for the outcome of sick cats (NLR sensitivity: 37.9%, specificity: 86.4%; LMR sensitivity: 69.0%, specificity: 61.0%). Many different disease categories were associated with increased NLR and decreased LMR compared to controls, but the overall prognostic performance of the two leucocyte ratios was suboptimal.

Investigation of hypomagnesaemia prevalence and underlying aetiology in a hospitalised cohort of dogs with ionised hypocalcaemia.

OBJECTIVES: Calcium is the most abundant mineral in the body and plays a critical role in a wide range of physiological processes. Low concentrations of ionised calcium, the most metabolically available form of calcium, have been linked to an increased risk of adverse clinical outcomes in dogs. Magnesium plays an important role in parathyroid hormone function. The objective of this study was to define the prevalence and aetiology of hypomagnesaemia in a hospitalised cohort of dogs with ionised hypocalcaemia (IHC). METHODS: A total magnesium reference interval was established using serum biochemistry results from 346 clinically healthy dogs. The clinical records of dogs with IHC were reviewed, and concurrent serum magnesium concentrations were recorded alongside clinical signs and underlying aetiology. The prevalence, clinical presentation and aetiology of hypomagnesaemia were examined in the IHC population. RESULTS: Two hundred and ninety-five IHC dogs were identified. Hypomagnesaemia was identified in 22%. Total magnesium concentration was significantly higher in dogs with renal disease. The most common cause of concurrent hypomagnesaemia and IHC was gastrointestinal diseases. CONCLUSION: Low concentrations of serum magnesium occur in approximately one fifth of all dogs with IHC. Further studies are required to clarify the link between magnesium status, IHC and clinical outcome.

Effect of anaemia and erythrocyte indices on canine glycated haemoglobin.

BACKGROUND: The major fraction of glycated haemoglobin (HbA1c) depends on blood glucose concentration and erythrocyte lifespan, and consequently erythrocyte indices may affect HbA1c; our objective was to study this effect in dogs. METHODS: Blood samples from two (healthy and anaemic) age- and sex-matched, normoglycaemic populations were prospectively included. Advia 120 and Capillarys 2 flex-piercing were used for the haematological and HbA1c analyses, respectively. RESULTS: Lower mean HbA1c was found in dogs with regenerative (n = 8, 0.88 ± 0.58%) and non-regenerative anaemia (n = 12, 1.36 ± 0.56%) compared to healthy ones (n = 40, 1.68 ± 0.48%); the difference was significant (p < 0.001) between the healthy dogs and those with regenerative anaemia. HbA1c was significantly correlated (p < 0.05) with red blood cell count (r = 0.506), haemoglobin (r = 0.474), haematocrit (r = 0.467), mean corpuscular volume (r = -0.289), mean corpuscular haemoglobin concentration (r = 0.284), red cell distribution width (r = -0.286) and reticulocytes (rs = -0.542). CONCLUSION: Anaemia, particularly if regenerative, can lower HbA1c. The significant correlation between HbA1c and erythrocyte indices likely reflects the effect of erythrocyte turnover on HbA1c.

Differential white blood cell counts in rabbits: a comparison of the Advia 2120 and a manual method.

We evaluated the performance of the Advia 2120 (Siemens) differential leukocyte count (A-Diff) compared to the manual method (M-Diff) in rabbits. EDTA-anticoagulated blood samples collected for diagnostic purposes were analyzed within 6 h of collection. The M-Diff was performed blindly by 2 observers on blood smears by counting 200 cells. We initially included 117 samples; 25 samples were excluded because of suboptimal gating of leukocytes in the Advia peroxidase cytogram or poor blood smear quality. The correlation between the A-Diff and M-Diff was very high for heterophils (r = 0.924, p < 0.001) and lymphocytes (r = 0.903, p < 0.001), high for basophils (r = 0.823, p < 0.001), moderate for monocytes (r = 0.645, p < 0.001), and low for eosinophils (r = 0.336, p = 0.001). The Passing-Bablok regression analyses revealed a small-to-moderate constant error for lymphocytes and a slight constant error for basophils. Small proportional errors were detected for heterophils, lymphocytes, and eosinophils. The Bland-Altman analyses revealed that the Advia significantly underestimates heterophils and overestimates lymphocytes compared to M-Diff. The biases for the other leukocytes were minimal and likely clinical insignificant; however, our results, particularly for eosinophils, should be interpreted cautiously given the observed low percentages in our samples. Given the observed biases in heterophil and lymphocyte percentages in the Advia 2120 CBC results in rabbits, method-specific reference intervals should be used. The Advia can recognize leporine basophils. Evaluation of blood smears is still recommended to investigate abnormal results and erroneous cytograms reported by the Advia.

A comparison study between the results of the Siemens ADVIA 120 analyzer and the manual method for differential leukocyte counts in sheep.

BACKGROUND: The ADVIA 120 is a widely used hematology analyzer, which has not been previously validated for determining differential leukocyte counts in sheep. OBJECTIVES: We aimed to compare differential leukocyte counts on the ADVIA 120 (A-Diff) with counts obtained using the manual method (M-Diff) in sheep. METHODS: Ethylenediaminetetraacetic acid-anticoagulated blood samples analyzed within 4 hours of collection were used. Samples with inappropriately filled tubes, detectable clots, overtly erroneous ADVIA peroxidase cytograms, and poor-quality blood smears were excluded from the study. Two independent observers compared the results of the A-Diff with those of the M-Diff. The M-diff was performed by counting 200 leukocytes on a blood smear. RESULTS: Overall, 88 samples (44 rams and 44 ewes) were included. The correlation between the A-Diff and M-Diff was high for neutrophils (r = .873, P < .001), lymphocytes (r = .863, P < .001), and eosinophils (r = .750, P < .001), and low for monocytes (r = .212, P = .048). The Passing-Bablok regression analyses revealed constant error for eosinophils [1.17%; 95% confidence interval (CI): 0.67%, 1.55%] and proportional error for lymphocytes (0.84; 95% CI: 0.74, 0.95) and eosinophils (0.85; 95% CI: 0.74, 0.96). The Bland-Altman analyses revealed negative biases of 2.4% and 3.0% for neutrophils and lymphocytes, respectively, and positive biases of 3.2% and 0.8% for monocytes and eosinophils, respectively. The extremely low basophil percentages precluded a meaningful method comparison for this leukocyte type. CONCLUSIONS: The ADVIA 120 appears to perform well for determining neutrophil, lymphocyte, and eosinophil percentages in sheep as compared with the manual method. However, blood smear examinations are recommended for the confirmation of abnormal differential leukocyte count results.

Effects of surgery on free and total 25 hydroxyvitamin D concentrations in dogs.

BACKGROUND: It is unclear whether a low total 25(OH)D concentration is a cause or consequence of illnesses. To address this knowledge gap, studies measuring free and total 25(OH)D during the evolution and resolution of an inflammatory process are required. OBJECTIVES: Serum total and free 25(OH)D concentrations would transiently decline after cruciate surgery in dogs. ANIMALS: Seventeen client-owned dogs with a spontaneous cranial cruciate ligament rupture (CCLR). METHODS: A longitudinal cohort study involving the measurement of serum concentrations of total and free 25(OH)D, total calcium, creatinine, albumin, phosphate, C-reactive protein and plasma ionized calcium, at 1 day before and a median time of 1 and 60 days after surgical treatment of CCLR. RESULTS: Median serum concentrations of total 25(OH)D before surgery (80.3 nmoL/L [range, 43.5-137.3]) significantly declined immediately after surgery; (64.8 nmoL/L [range, 36.3-116.5] 1 day after surgery, P < .005) before increasing to become nonsignificantly different from concentrations before surgery at day 60 after surgery (median 78.0 nmoL/L [range, 24.2-115.8], P = .14). In contrast, median free 25(OH)D concentrations before surgery (7.6 pg/mL [range, 3.8-12.2]) significantly increased immediately after surgery (9.2 pg/mL [range, 5.2-15.7], P < .05) before declining to become nonsignificantly different from before surgery concentrations at day 60 after surgery (median 6.2 pg/mL [range, 4.0-15.8], P = .37). CONCLUSION AND CLINICAL IMPORTANCE: This study reveals the difficulties of assessing vitamin D status in dogs following elective surgery.

Capillary hemoglobin electrophoresis of healthy and anemic dogs: Quantification, validation, and reference intervals of hemoglobin fractions.

Despite the advances in canine medicine and the rapid gaining of attention of canine models in biomedical field and particularly in hemoglobin genes research, the studies on canine hemoglobin composition are sparse with ambiguous findings. Our aim was: i) to investigate the electrophoretic pattern of canine hemoglobin and the possible effects of age, sex, and anemia using a capillary electrophoresis assay, and ii) to validate this assay and calculate reference intervals (RIs) for canine hemoglobin fractions. Blood samples were collected from 53 healthy and 42 dogs with regenerative and non-regenerative anemias. The Sebia Capillarys 2 flex-piercing was used for hemoglobin analysis and it was validated using canine blood samples. R statistical language was employed for the statistical analyses. A major hemoglobin fraction (named HbA0) and a minor one (named HbA2) were identified in 100% and 47.4% of samples, respectively. The within-run and between-run CV was 0.1% for HbA0, and 9.1% and 11.2% for HbA2, respectively. The extremely narrow range of HbA0 and HbA2 values hampered a linearity study using canine blood samples. The RIs for HbA0 and HbA2 were 98.9-100% and 0-1.1%, respectively. HbA0 and HbA2 values were not significantly correlated with age (P = 0.866) or reticulocyte count (P = 0.731). No differences were observed in the median HbA0 and HbA2 between the two sexes (P = 0.887), and healthy and anemic dogs (P = 0.805). In conclusion, the capillary electrophoresis revealed a major hemoglobin fraction and an inconsistently present minor fraction. No effect of age, sex, anemia, or regenerative status of anemia was detected. The assay used was validated and RIs were generated, so as to be suitable for use in future investigations.

Circulating and bone marrow myeloid cells containing Leishmania amastigotes in a case of advanced canine leishmaniosis.

A 5-y-old male Poodle mix was presented with intermittent vomiting, anorexia, and weight loss. Physical examination revealed emaciation, lethargy, dehydration, hypothermia, respiratory distress, and splenomegaly. Based on clinicopathologic, serologic, and parasitologic findings, diagnoses of severe leishmaniosis and dirofilariasis were made. Extracellular, intraneutrophilic, and intramonocytic Leishmania amastigotes were observed on blood smear and buffy coat smear examination. In blood smears, 0.2% of neutrophils were observed to be infected; in buffy coat smears, 0.5% of neutrophils and 0.1% of monocytes were found to be infected. Leishmania amastigotes were also found engulfed by eosinophils and neutrophil precursors in bone marrow aspiration cytology. The detection of Leishmania amastigotes in blood smears is rare, and the clinical significance is uncertain. In circulating blood, Leishmania amastigotes are primarily found phagocytized by neutrophils. Although debatable, there is growing evidence that neutrophils are used as carriers enabling the "silent entry" of the protozoa into macrophages ("Trojan horse" theory). To date, cytologic screening of blood smears for the diagnosis of canine leishmaniosis is not a routine practice. Clinical pathologists and practitioners should be aware that Leishmania amastigotes may be present in neutrophils and less frequently monocytes during blood smear evaluation; neutrophil precursors and eosinophils may also be parasitized in bone marrow specimens.

Hereditary methemoglobinemia in a cyanotic cat presented for ovariohysterectomy.

A 1-year-old, female, domestic shorthair cat with a history of cyanotic mucous membranes for several months was referred for ovariohysterectomy. Blood samples exhibited a noticeably brownish discoloration, while laboratory screening revealed mild-to-moderate erythrocytosis and near normal partial arterial oxygen pressure. Blood methemoglobin content was 41% of total hemoglobin concentration, and erythrocytic methemoglobin reductase activity was < 1% compared with control samples. A diagnosis of hereditary methemoglobinemia was established. After an intravenous injection of methylene blue, the cat's mucous membranes became transiently pink, and the ovariohysterectomy was uneventful. Methylene blue may have improved safety during anesthesia and surgery. Hereditary methemoglobinemia should be considered in persistently cyanotic cats with normal partial arterial oxygen pressure and lack of evidence of cardiopulmonary disease, anemia, or toxin exposure.

Méthémoglobinémie héréditaire chez une chatte cyanotique présentée pour une ovariohystérectomie. Une chatte domestique âgée de 1 an avec une anamnèse de muqueuses cyanotiques pendant plusieurs mois a été recommandée pour l'ovariohystérectomie. Des prélèvements sanguins présentaient une décoloration brune manifeste tandis que les tests de laboratoire ont révélé une érythrocytose de légère à modérée et une pression d'oxygène artérielle partielle presque normale. Le contenu de méthémoglobine sanguine était de 41 % de la concentration totale des hémoglobines et l'activité de la réductase de la méthémoglobine érythrocytaire était < 1 % comparativement aux prélèvements témoins. Un diagnostic de méthémoglobinémie héréditaire a été posé. Après une injection intraveineuse de bleu de méthylène, les muqueuses du chat sont devenues provisoirement roses et l'ovariohystérectomie a été réalisée sans complications. Le bleu de méthylène peut avoir amélioré l'innocuité durant l'anesthésie et la chirurgie.(Traduit par Isabelle Vallières).

Hematologic, biochemical, hormonal, and redox status alterations during reproductive activity in adult rams of two breeds.

BACKGROUND: Reproduction is a crucial, energy-consuming physiologic activity, which can temporarily disturb the homeostatic balance of the organism. Although rams are commonly placed in intense breeding programs on contemporary sheep farms, the clinicopathologic and redox status alterations have not been adequately studied during reproductive activity. OBJECTIVES: The objective was to investigate the clinicopathologic and redox status changes in rams during reproductive activity. METHODS: Thirty-seven (19 Chios and 18 Florina breed) adult, healthy rams were individually mated with ten estrus-synchronized ewes of the same breed. Blood samples were collected prior to mating, during mating, and postmating. CBC (Advia 120), cytologic blood smear evaluation, biochemical analyses (Flexor E, AVL 9180 Electrolyte Analyzer), and thyroxine measurements (Immulite 1000) were performed. The reactive oxygen metabolites (d-ROMs) test, the biological antioxidant potential (BAP) test, and oxidative stress index were used to assess redox status. The linear mixed effects model (statistical language R) was used for statistical analyses. RESULTS: Many, mostly breed-independent, clinicopathologic changes were detected during reproductive activity. Conversely, redox status alterations were found to be breed-dependent. CONCLUSIONS: Intense reproductive activity was related to mild, acute muscle damage in both breeds and mild oxidative stress in Florina rams, whereas Chios rams exhibited oxidative stress resistance. The observed clinicopathologic and redox status alterations were generally consistent with those reported during various forms of physical activity and exercise in animals and humans. Intense reproductive activity does not seem to be physiologically innocuous; however, it appears to be a relatively mild muscle-damaging physical activity.

Canine and feline dirofilariosis in a highly enzootic area: first report of feline dirofilariosis in Greece.

Dirofilaria immitis (heartworm) is enzootic in many areas of the world and quite prevalent in southern European countries. Although dogs are the main host of the parasite, cats may also be infected, and the prevalence of feline dirofilariosis is associated with the respective prevalence of canine infection in any given area. The aim of the present study was to investigate the proportion of D. immitis infection among dogs and cats that were not under any kind of prophylactic treatment and were living in a heartworm enzootic area. In total, 180 stray animals (148 dogs and 32 cats) living in a shelter in Northern Greece were examined for heartworm infection by the Knott's test and serology (antigen and in cats also antibody detection), and additionally echocardiography in the infected cats. Thirty-seven (25%, CI 18.7-32.5%) of the dogs and 3 (9.4%, CI 3.2-24.2%) of cats were found to be positive, by at least one of the tests applied. In 2 of the infected cats, the parasites were also detected by echocardiography. One of the positive cats died suddenly 1 year after diagnosis and at necropsy two decomposing D. immitis were found in the right ventricle and pulmonary artery. This is the first report of confirmed feline dirofilariosis in Greece. The detected proportion of infection in cats was 38% of the respective canine infection in the examined shelter. The results of the present study underline the high risk of infection of cats living in enzootic areas and the imperative character of preventive measures in such conditions.

Whole-genome sequencing of a CTX-M-11-encoding and quinolone-non-susceptible Klebsiella pneumoniae ST194 isolate from a hospitalised dog in Greece.

OBJECTIVES: The emergence and spread of transferable ß-lactamases among Enterobacteriaceae is a major problem both to human and veterinary medicine and is an important contributing factor to the development of multidrug-resistant bacterial isolates. In the present study, whole-genome sequencing of a Klebsiella pneumoniae isolate (LKP817909) resistant to first- and second-generation cephalosporins and non-susceptible to fluoroquinolones, isolated from a urine sample of a hospitalised dog, was performed. METHODS: Genome sequencing was performed on an Illumina MiniSeq Sequencing System. Multilocus sequence typing (MLST) was performed using a BLAST-based approach, whereas antimicrobial resistance genes and plasmid replicons were identified by ResFinder and PlasmidFinder, respectively. The Rapid Annotation using Subsystem Technology (RAST) server v.2.0 was used for genome annotation. RESULTS: Data analyses revealed the complete resistome of isolate LKP817909, which included the cefotaximase-München-11 (CTX-M-11) extended-spectrum ß-lactamase together with 11 other resistance genes. Ten resistance genes were located on plasmids and two on the chromosome. CONCLUSIONS: To the best of our knowledge, this is the first detection of a CTX-M-11-producing K. pneumoniae isolated from a canine. The whole genome sequence of the isolate has been deposited at GenBank to serve as a future reference.

Combined and breed-specific RIs for hematologic, biochemical, and hormonal analytes in Chios and Florina adult rams.

BACKGROUND: Clinical pathology investigations are essential to evaluate the health status and practice management of ruminants. Appropriate and accurate RIs are required for the interpretation of laboratory results. Despite substantial phenotypic differences and management-related disparities between male and female sheep, RIs in rams are sparse and limited by small reference populations and outdated methods. OBJECTIVES: The purpose of this study was to establish RIs for hematologic, biochemical, and hormonal analytes in adult rams using controlled preanalytic and analytic procedures, and to investigate whether breed-dependent partitioning of RIs is required. METHODS: Reference individuals were selected by a direct a priori method. Blood was collected from 128 healthy adult rams representing 2 Greek breeds (64 Chios and 64 Florina). Hematologic analysis was performed on the Advia 120, while differential WBC counts were manually performed on Giemsa-stained blood smears. Flexor E, AVL 9180 Electrolyte Analyzer, and Immulite 1000 were used for biochemical and hormonal analyses, respectively. Combined and breed-specific RIs were calculated using nonparametric and robust methods, respectively. RESULTS: Five outliers were detected based on laboratory results. Partitioning of RIs, based on both statistical and nonstatistical criteria, was recommended for some of the analytes. CONCLUSIONS: The RIs are in some agreement with those in the literature. The observed differences may be attributed to preanalytic and analytic factors. The RIs determined in this study can be used as a guide for the interpretation of laboratory results in rams and can potentially be adopted by veterinary laboratories, provided that similar equipment and reagents are used.

Reference intervals for serum reactive oxygen metabolites, biological antioxidant potential, and oxidative stress index in adult rams.

OBJECTIVE To establish reference intervals for serum reactive oxygen metabolites (ROMs), biological antioxidant potential (BAP), and oxidative stress index (OSi) in adult rams by use of controlled preanalytic and analytic procedures. ANIMALS 123 healthy 1- to 4-year-old rams of 2 Greek breeds (Chios [n = 62] and Florina [61]). PROCEDURES 4 hours after rams were fed, a blood sample was obtained from each ram, and serum was harvested. Concentrations of ROMs and BAP were measured colorimetrically on a spectrophotometric analyzer. The OSi was calculated as ROMs concentration divided by BAP concentration. Combined and breed-specific reference intervals were calculated by use of nonparametric and robust methods, respectively. Reference intervals were defined as the 2.5th to 97.5th percentiles. RESULTS Reference intervals for ROMs, BAP, and OSi for all rams combined were 65 to 109 Carratelli units, 2,364 to 4,491 µmol/L, and 18.2 to 43.0 Carratelli units/(mmol/L), respectively. Reference intervals of Chios rams for ROMs, BAP, and OSi were 56 to 113 Carratelli units, 2,234 to 4,290 µmol/L, and 12.9 to 38.4 Carratelli units/(mmol/L), respectively. Reference intervals of Florina rams for ROMs, BAP, and OSi were 68 to 111 Carratelli units, 2,337 to 4,363 µmol/L, and 14.1 to 38.1 Carratelli units/(mmol/L), respectively. CONCLUSIONS AND CLINICAL RELEVANCE Reference intervals calculated in this study can be used as a guide for the interpretation of ROMs, BAP, and OSi results in rams and, under appropriate conditions, can be adopted for use by veterinary laboratories.