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.

Abortion Related to Toxoplasma gondii Infection in a Bactrian Camel (Camelus bactrianus) in Greece: A Case Report.

A female, 5 yr old Bactrian camel was presented to the Exotic and Wildlife Medicine Unit, School of Veterinary Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece, with severe dehydration, depression, anorexia, mild dyspnea and diarrhea. Supportive treatment immediately initiated with fluids, electrolytes and broad-spectrum antibiotics. The general condition of the animal was stable for the next 3 days, but at 4th day became worse, since the camel remained in sternal recumbency, denied to drink water and abortion of a mummified fetus was noticed. The aborted fetus and fetal membranes were submitted for laboratory examinations (bacterial cultures, MZN, cytology, PCR) that revealed Toxoplasma gondii infection. Treatment with sulfadimidine improved the situation of the animal that returned to its farm 1 week later. This seems to be the first reported case in the literature of confirmed toxoplasmic abortion in camels.

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.

Effect of anaesthesia on cell-mediated immunity in dogs undergoing mastectomy for mammary cancer.

OBJECTIVE: To investigate if anaesthesia for canine cancer mastectomy further influences host cell-mediated immunity (CMI) promoting cancer progression. STUDY DESIGN: A randomized, controlled, blinded clinical study. ANIMALS: A total of 20 bitches with malignant mammary tumours of clinical stage II or III undergoing the same type of mastectomy (regional mastectomy). METHODS: Dogs were randomly allocated to one of two anaesthetic groups (10 per group). The anaesthetic protocol of group A used minimally immunosuppressive drugs (tramadol, robenacoxib, propofol), whereas that of group B (control) used more immunosuppressive drugs (morphine, fentanyl, thiopental, isoflurane). For each animal, measurements of white blood cells (WBCs), neutrophils and lymphocytes, and flow cytometric assessment of T cells (CD3+), helper T cells (CD4+), cytotoxic T cells (CD8+) and CD5low+ T cells were performed prior to anaesthesia (day 0) and on days 3 and 10 postsurgery. Data were analysed using a General Linear Model for repeated measures and presented as mean ± standard deviation, p ≤ 0.05. RESULTS: In all animals, on day 3, WBCs and neutrophils were significantly increased (p < 0.0005), while flow cytometry revealed significantly decreased relative percentages of T cells (CD3+) (p = 0.003) and their subpopulations CD4+ (p = 0.006), CD8+ (p = 0.029) and CD5low+ (p = 0.031). Specifically, on day 3, the cytotoxic T cells (CD8+) were significantly decreased (p = 0.05) only in group B, whereas the CD4+ (p = 0.006) and CD5low+ (p = 0.008) T cells in group A. The only significant difference between groups was found preoperatively in the CD4+/CD8+ ratio, which was higher in group A (p = 0.006). CONCLUSIONS AND CLINICAL RELEVANCE: In dogs with mammary cancer undergoing regional mastectomy, a significant decrease in components of CMI was observed on day 3 postsurgery in both anaesthetic groups. Some indication, however, for better preserved cellular immunity by less immunosuppressive anaesthetic/analgesic drugs was detected, rendering their use advisable.

Bronchoscopy and Lung Fine-Needle Aspiration for Antemortem Evaluation of Pulmonary Involvement in Dogs with Naturally Occurring Canine Leishmaniosis.

Clinical manifestations from the lower respiratory tract are rare in canine leishmaniosis (CanL), making bronchoscopy and lung fine-needle aspiration (FNA) seldomly justified. The aim of this prospective study was to investigate the involvement of Leishmania infantum in the lungs of dogs with naturally occurring CanL by bronchoscopy and examination of bronchoalveolar lavage fluid (BALF), bronchial mucosa biopsies, and FNA, using immunodiagnostics. Dogs with relevant concurrent diseases and azotemia were excluded. Cough was detected in 5/31 (16.1%) dogs. Lesions (hyperemia, edema, mucosal granularity, secretions) were identified upon bronchoscopy in 19/31 (61.3%) dogs. The cytology of BALF revealed histiocytic inflammation in 14/31 (45.2%) dogs; the parasite was identified in one dog (3.2%). The immunofluorescence antibody test in BALF was positive in 15/31 (48.4%) dogs. Histopathology of bronchial mucosa and/or adjacent alveoli revealed lesions (mononuclear cell infiltration, fibrosis, edema, thickening of the inter-alveolar septa) in 24/31 (77.4%) dogs, with no Leishmania amastigotes. Positive antigen staining was observed within the cytoplasm of mononuclear cells in immunocytochemistry and immunohistochemistry. Μononuclear cells showed antigenic positivity in bronchial mucosa (27/31; 87.1%), BALF (30/31; 96.8%), and lung FNA (27/31; 87.1%). In conclusion, lungs seem to be affected from CanL more commonly than previously believed, and bronchoscopy allows obtaining valuable samples for antemortem diagnosis.

Effect of major versus minor mastectomy on host immunity in canine mammary cancer.

Surgical procedures can affect host immunity proportionally to the extent of surgical trauma. In cancer cases, surgery-induced immunosuppression can potentially promote tumour metastasis. The aim of this study was to investigate, in bitches with malignant mammary tumours, whether major surgery (total unilateral mastectomy or bilateral regional mastectomy) has a more negative effect than minor surgery (unilateral regional mastectomy) on components of host immunity. Twenty bitches with mammary cancer of clinical stage II or III were allocated to group A (minor surgery) or group B (major surgery) of 10 animals each receiving the same anaesthetic protocol for mastectomy. Immune cell measurements in blood [number of leukocytes, neutrophils, lymphocytes and platelets, and relative percentages of T-lymphocytes (CD3+) and their CD4+, CD8+ and CD5low+ subpopulations] were performed before anaesthesia (day 0) and on days 3 and 10 post-mastectomy. On day 3, leukocytes, neutrophils and platelets numbers were higher (p = 0.016, 0.032 and 0.017, respectively) in group B than in group A. For all 20 bitches, T-lymphocytes and the CD4+, CD5low+ T-cells were significantly decreased on day 3, but no significant differences were noted between groups. Minor mastectomy seemed to preserve innate immunity better than major mastectomy, but cellular immunity was rather equally affected.

Hematology reference intervals during the prepartum period, first week after calving, and peak lactation in clinically healthy Holstein cows.

Dairy cows face precipitous metabolic adaptations during the first postpartum week. Increasing knowledge of their hematologic profiles during this period could benefit both veterinary clinical pathologists and bovine practitioners. The objectives of this study were: (a) to establish period-specific RIs for Holstein dairy cows and (b) to assess the potential simultaneous effect of several factors on hematology parameters. Blood samples from clinically healthy cows of nine herds were used to establish hematology RIs for these periods. There were 68 cows in the prepartum period (PP), 247 and 218 cows at 2 and 8 days after calving (2 and 8 days in milk [DIM 2 and DIM 8], respectively), and 87 cows in peak lactation (PL). A complete blood count evaluation was performed using the ADVIA 120 analyzer. Linear models estimated the analytes associated with parity. RIs were calculated with Reference Value Advisor. Parity had a significant effect on analytes at all stages. Marked differences were evident between DIM 2 and 8 regarding red blood cell (RBC) counts, hematocrits, hemoglobin concentrations, and white blood cell (WBC), monocyte, and eosinophil counts. Reference intervals of RBC counts, hematocrits, and hemoglobin concentrations at DIM 2 were higher than those at PP and PL. This study provides evidence that period-specific RIs should be used for Holstein cows when making clinical decisions, especially during the critical first week postpartum.

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.

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.

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.

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.

Seroprevalence and risk factors associated with Ehrlichia canis in a hospital canine population.

BACKGROUND: Ehrlichia canis (E canis) infection has been documented in a few small canine case series in Greece. However, there is limited information on the prevalence of exposure to, or the potential risk factors associated with E canis seroreactivity in a large native canine population. OBJECTIVES: The objectives of this study were to evaluate E canis seroprevalence in dogs admitted to a veterinary teaching hospital, and to investigate the potential association between seropositivity and signalment, health status, the serologic assays used, and selected clinical and clinicopathologic abnormalities. METHODS: The medical records of 850 client-owned dogs, tested using three in-office serologic assays, were retrospectively reviewed. RESULTS: The E canis seroprevalence was significantly higher in sick (54.9%) compared with healthy (33.9%) dogs. Seropositivity differed significantly between the serologic assays used in this study (ImmunoComb vs SNAP 3Dx/SNAP 4Dx). Dogs presenting with bleeding tendencies, anemia, thrombocytopenia, leukopenia, pancytopenia, and hyperproteinemia were more likely to be E canis seropositive, and the median hematocrit (HCT), white blood cell (WBC), neutrophil, and platelet values were significantly lower in seropositive compared with seronegative dogs. CONCLUSIONS: A high E canis seroprevalence was documented in a canine population living in an endemic area. Selected clinicopathologic variables might be useful indicators of E canis exposure and could allow the prioritization of serologic testing in the clinical setting.

Cross-Sectional Serosurvey and Factors Associated with Exposure of Dogs to Vector-Borne Pathogens in Greece.

Blood samples from 2620 dogs living in 7 different areas were used for the detection of antibodies against Ehrlichia canis and Borrelia burgdorferi and Dirofilaria immitis antigen. Previously published seropositivity data against Leishmania infantum from the same samples were also used to identify multiple-pathogen seropositivity. The associations between seropositivity against each pathogen and gender, age, utility, hair length, and region of residence were evaluated by multivariate logistic regression analyses. The prevalence of seropositivity against E. canis, B. burgdorferi, and D. immitis was 12.25%, 2.23%, and 5.96%, respectively. Double- and triple-pathogen seropositivity was detected in seven different combinations. Age and region of residence were strongly associated with seropositivity against all pathogens. The association between seropositivity and the area of residence highlights the need for regular testing of dogs for vector-borne pathogens in areas with similar conditions to define control measures.

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.

The effect of subchronic oral exposure to zearalenone on hematologic and biochemical analytes, and the blood redox status of adult rabbit bucks.

BACKGROUND: Zearalenone (ZEN) is a mycoestrogen with a ubiquitous presence in animal feeds, which also has hematotoxic, hepatotoxic, nephrotoxic, and immunotoxic properties. However, there is a paucity of literature that discusses the effects of ZEN on rabbits. OBJECTIVES: The aim of this study was to evaluate the effect of a prolonged, low-level (50 µg ZEN/kg body weight) exposure on the clinicopathologic and redox status analytes of rabbit bucks. METHODS: Ten adult bucks were included in the study. Each underwent a 7-week control period, followed by a 7-week exposure period. Water or ZEN solutions were daily administered orally (0.5 mL) during the control and exposure periods, respectively. Blood samples were collected weekly for Complete Blood Counts, serum biochemical analyte and reactive oxygen metabolite (ROM) measurements. Data were analyzed using a mixed model, and the level of significance was set at a P of <0.05. RESULTS: During the ZEN exposure period, significant increases were noted in the red blood cell distribution width (RDW) and mean platelet volumes (MPVs), as well as in the white blood cell, monocyte, and eosinophil counts. Significant increases were observed in aspartate aminotransferase and total bilirubin, whereas urea, creatinine, glucose, total calcium, sodium, and potassium concentrations were significantly decreased. The ROM concentrations did not differ significantly between the control and ZEN exposure periods. CONCLUSIONS: Under the present experimental conditions, ZEN affected some of the clinicopathologic analytes of adult rabbit bucks; these changes were mostly indicative of mild hepatocellular damage and dysfunction, inflammatory and/or allergic responses, and renal tubular damage. A ZEN dose of 50 µg/kg body weight did not seem to affect the blood redox status of bucks, as evaluated by the ROM concentrations.

Quantitative characterization of viscoelastic properties of synovial fluid from forelimb joints of orthopedically normal Thoroughbreds and warmblood horses.

OBJECTIVE: To determine whether differences existed in the viscoelastic properties of synovial fluid samples from the metacarpophalangeal, intercarpal, and distal interphalangeal joints of orthopedically normal athletic horses. ANIMALS: 45 warmblood horses and 30 Thoroughbreds (age range, 4 to 16 years). PROCEDURES: Synovial fluid samples were aseptically obtained via arthrocentesis from 1 metacarpophalangeal, intercarpal, and distal interphalangeal joint of each horse, and nucleated cell counts were performed. A commercial ELISA was used to measure sample hyaluronic acid concentrations, and full rheological characterization of samples was performed to measure the elastic or storage modulus G' and viscous or loss modulus G" at 37.5°C (representing the body temperature of horses). Findings were compared among joints and between breed groups by means of ANOVA. RESULTS: Significant differences in synovial fluid G' and G" values were identified between Thoroughbreds and warmblood horses for the metacarpophalangeal joint, between the metacarpophalangeal and intercarpal joints of Thoroughbreds, and between the metacarpophalangeal and distal interphalangeal joints and intercarpal and distal interphalangeal joints of warmblood horses. No significant differences were identified between breed groups or among joints in synovial fluid hyaluronic concentrations or nucleated cell counts. CONCLUSIONS AND CLINICAL RELEVANCE: Viscoelastic properties of the forelimb joints of orthopedically normal Thoroughbreds and warmblood horses differed within and between these 2 groups, mainly as a function of the evaluated joint. To the authors' knowledge, this was the first study of its kind, and additional research is warranted to better understand the viscoelastic properties of synovial fluid in horses to optimize their locomotive function.