Hematologic abnormalities and flow cytometric immunophenotyping results in dogs with hematopoietic neoplasia: 210 cases (2002–2006)

Background: Growing interest in veterinary oncohematology has facilitated the recent development and advancement of new techniques, such as flow cytometry, for immunophenotyping hematopoietic neoplasia in animals. Objective: The aim of this retrospective study was to characterize hematologic abnormalities and flow cytometric immunophenotyping (FCI) results in cases of hematopoietic neoplasia in dogs. Methods: Signalment, CBC data, and FCI results were obtained for 210 dogs with blood samples submitted to our laboratory. Immunophenotyping was carried out using an Epics XL‐MCL flow cytometer and a panel of 10 antibodies (CD45, CD3, CD4, CD8, CD79, CD21, CD14, CD34, CD41/61, CD61). The prevalence and severity of hematologic abnormalities was determined for the different types of hematopoietic neoplasms. Results: Based on cell morphology and phenotype, cases were classified as: acute lymphoblastic leukemia (ALL, n=51), acute myeloid leukemia (AML, n=33), chronic lymphocytic leukemia (CLL, n=61), and leukemic high‐grade lymphoma (L‐HGL, n=65). Most cases of ALL (47/51) and L‐HGL (41/65) had a B‐cell phenotype, while most cases of CLL (54/61) had a T‐cell phenotype, with a high prevalence of the large granular lymphocyte subtype (49/61). Anemia was found in 85% of all cases and was significantly more severe in ALL and AML compared with CLL and L‐HGL. Neutropenia was seen in 64–78% of acute leukemias (AML and ALL) in contrast to no cases of CLL and 11% of L‐HGL. Thrombocytopenia was seen in 88–90% of acute leukemias in contrast to 15% of CLL and 40% of L‐HGL. Thrombocytopenia was more prevalent (71% vs 22%) and significantly more severe in T‐cell vs B‐cell L‐HGL. Conclusion: A standard CBC is useful in suggesting the type of hemoproliferative disorder and may also help to predict the phenotype, especially in cases of L‐HGL.     

Acute phase proteins in the diagnosis of bovine subclinical mastitis

Background: The California mastitis test (CMT) and somatic cell count (SCC) are commonly used for diagnosis of subclinical mastitis in cattle. Acute phase proteins (APPs), as alternative biomarkers of mastitis, may increase in concentration in the absence of macroscopic changes in the milk, or may precede the onset of clinical signs. Objective: The aim of this study was to compare the accuracy of APPs measured in milk and in serum with bacterial culture for the diagnosis of bovine subclinical mastitis. Methods: One hundred and seventy‐five Holstein cows were randomly selected from 7 dairy farms. Quarter milk and serum samples were taken from all cows. Milk samples were analyzed using a CMT and SCC, and for haptoglobin (MHp) and amyloid A (MAA) concentrations, and were also submitted for bacterial culture. Serum samples obtained concurrently were analyzed for haptoglobin (SHp) and amyloid A (SAA). Two‐sample Wilcoxon (Mann–Whitney) test was used to compare SCC, MAA, MHp, SAA, and SHp concentrations between culture‐positive and culture‐negative animals. Receiver‐operating characteristic analysis was used to assess the performance of each test using bacterial culture as the reference method. Results: MAA concentration was the most accurate of the 5 tests, with a sensitivity of 90.6% and specificity of 98.3% at concentrations >16.4 mg/L. MAA and MHp had significantly larger areas under the curve than the respective serum proteins, SAA and SHp. Conclusions: The results suggest that measuring haptoglobin and amyloid A in milk is more accurate than serum analysis for the diagnosis of subclinical mastitis in Holstein cows.     

Acute phase protein concentrations in retired racing Greyhounds

Background: Retired racing Greyhounds are popular as pets. Greyhounds have several differences in physiological values compared with other breeds, including lower serum α‐ and β‐globulin concentrations. We hypothesized that lower acute phase protein (APP) concentrations could contribute to lower α‐ and β‐globulin concentrations in this breed. Objectives: The purpose of this study was to compare serum concentrations of several APPs in Greyhounds with those of other dog breeds. Methods: We measured the serum concentrations of C‐reactive protein (CRP), haptoglobin (Hp), acid‐soluble glycoprotein (ASG), ceruloplasmin (CP), and serum amyloid A (SAA) in 15 clinically healthy retired racing Greyhounds and 11 age‐ and gender‐matched healthy nonGreyhound controls using previously validated methods. Results were compared by Student's t‐tests. Results: The concentration of Hp by both colorimetric and immunoturbidimetric methods was significantly lower in Greyhounds than in nonGreyhound dogs (P=.0009 and .019, respectively). The concentration of ASG was also significantly (P=.007) lower in Greyhounds, but CRP and CP concentrations were not significantly different between groups. SAA concentration was below the detection limit of the method in all dogs. Conclusions: The low serum concentrations of Hp and ASG should be taken into consideration when interpreting APP results in Greyhounds. Because both Hp and some ASG migrate in the α‐globulin fraction, these results may explain the low α‐globulin concentrations in Greyhounds.     

Infectivity of pestivirus following persistence of acute infection

Bovine viral diarrhoea virus (BVDV) is an endemic pathogen worldwide and eradication strategies focus on the identification and removal of persistently infected (PI) animals arising after in utero infection. Despite this, acute infections with BVDV can persist for months or years after the removal of the PI source despite repeated screening for PIs and tight biosecurity measures. Recent evidence for a prolonged duration of viraemia in the testicles of bulls following acute BVDV infection suggests the possibility of a form of chronic persistence that may more closely resemble the persistence strategies of hepatitis C virus (HCV). To investigate the potential for virus transmission from infected and recovered cattle to virus naïve hosts we established an acute infection of 5 BVDV-naïve calves and monitored animals over 129 days. Infectious BVDV was detected in white blood cells between days 3 and 7 post-challenge. The animals seroconverted by day 21 post-infection and subsequently were apparently immune and free from infectious virus and viral antigen.Animals were further monitored and purified white blood cells were stimulated in vitro with phytohaemagglutinin A (PHA) during which time BVDV RNA was detected intermittently.Ninety-eight days following challenge, blood was transferred from these apparently virus-free and actively immune animals to a further group of 5 BVDV-naïve calves and transmission of infection was achieved. This indicates that BVDV-infected, recovered and immune animals have the potential to remain infectious for BVDV-naïve cohorts for longer than previously demonstrated.     

Improvement in insulin resistance and reduction in plasma inflammatory adipokines after weight loss in obese dogs

Obesity is now a major disease of dogs, predisposing to numerous disorders including diabetes mellitus. Adipocytes are active endocrine cells, and human obesity is characterized by derangements in inflammatory adipokine production. However, it is unclear as to whether similar changes occur in dogs. The purpose of the current study was to assess insulin sensitivity and inflammatory adipokine profiles in dogs with naturally occurring obesity and to investigate the effect of subsequent weight loss. Twenty-six overweight dogs were studied, representing a range of breeds and both sexes. All dogs underwent a weight loss program involving diet and exercise. Body fat mass was measured by dual-energy x-ray absorptiometry; plasma concentrations of insulin, glucose, and a panel of inflammatory adipokines (including acute-phase proteins, cytokines, and chemokines) were also analyzed. Body fat mass before weight loss was positively correlated with both plasma insulin concentrations (Kendall τ = 0.30, P = 0.044) and insulin:glucose ratio (Kendall τ = 0.36, P = 0.022), and both decreased after weight loss (P = 0.0037 and 0.0063, respectively). Weight loss also led to notable decreases in plasma tumor necrosis factor-α (TNF-α), haptoglobin, and C-reactive protein concentrations (P < 0.05 for all), suggesting improvement of a subclinical inflammatory state associated with obesity. This study has demonstrated that in obese dogs, insulin resistance correlates with degree of adiposity, and weight loss improves insulin sensitivity. Concurrent decreases in TNF-α and adipose tissue mass suggest that in dogs, as in humans, this adipokine may be implicated in the insulin resistance of obesity.     

The use of receiver operating characteristic (ROC) analysis to assess the diagnostic value of serum amyloid A, haptoglobin and fibrinogen in traumatic reticuloperitonitis in cattle

Acute phase proteins (APPs) such as serum amyloid A (SAA), haptoglobin (Hp), and plasma fibrinogen (Fb) are diagnostic and prognostic biomarkers. This study determined the pattern of SAA in traumatic reticuloperitonitis (TRP) in cows, and compared the findings with Hp, and plasma Fb concentrations in the differential diagnosis of TRP using receiver operating characteristic (ROC) analysis. Blood samples were collected from 89 cows: 53 cases of TRP, 16 animals with other internal disorders and 20 healthy controls.SAA and Hp had a similar pattern and magnitude of changes in TRP. Using the ROC method, the optimal cut-off for the diagnosis of TRP was 68 μg/mL for SAA and 0.74 g/L for Hp, with 100% sensitivity and 86.1% specificity; either of these parameters may therefore be used as a sensitive and relatively specific tool for the differential diagnosis of TRP in cattle. The diagnostic accuracy of plasma Fb was significantly lower than either SAA or Hp (P < 0.01). The combined use of these APPs (whilst aware of their conditional interdependence) may not provide any additional diagnostic information than can be obtained using either SAA or Hp alone.     

Cu2+对脊尾白虾幼虾的急性毒性效应研究

[目的]研究Cu2+对脊尾白虾的毒性效应,揭示Cu2+对脊尾白虾的致毒机理。[方法]采用静水生物测试法开展了在不同浓度下铜离子对脊尾白虾的96 h急性毒性试验。[结果]暴露时间为24 h、48 h、72 h和96 h时,Cu2+对脊尾白虾的半致死浓度分别为50.35mg/L、26.73 mg/L、21.23 mg/L和18.07 mg/L。Cu2+对脊尾白虾的安全浓度为0.18 mg/L。[结论]脊尾白虾幼虾对Cu2+污染具有较强的耐受能力。     

强普生Ⅲ号毒性安全试验

采用动物毒性试验方法,对强普生Ⅲ号进行了毒性、安全性评价。结果显示:小鼠的急性毒性反应和死亡率与给药剂量成正比,强普生Ⅲ号的半数致死量(LD50)为44.20±2.96 mL/kg,LD50的95%可信限为47.26~41.35 mL/kg,表现为无急性毒性。亚慢性毒性试验,实验期间小鼠的临床表现、体质量变化、饲料消耗量、血常规检查、血清生化检查等各项指标,试验组与对照组均无显著差异,各组脏器剖检和病理学切片检查也均无病理学变化。吸入毒性试验,试验组鸡整体状况正常,72 h内无中毒反应和死亡,血清生化指标值均在正常范围内,与对照组无显著差异。