-Ehrlichia canis is the causative agent of canine monocytic ehrlichiosis. In order to evaluate platelet counts as a screening test for E. canis in an endemic area, 217 whole blood samples from dogs were divided into three groups: 71 non-thrombocytopenic samples (group A, platelet counts greater than 200 000/µL) and 146 thrombocytopenic samples (less than 200 000/µL). The thrombocytopenic group was further divided into 62 with platelet counts between 100 000-200 000/µL (Group B) and 84 samples with less than 100 000 platelets/µL (Group C). All samples were examined for the presence of a segment of the Ehrlichia canis 16S rRNA gene using a nested polymerase chain reaction. Sixty-seven of the 217 samples (30.9%) were positive for the presence of the E. canis 16S rRNA gene; 53 (63.1%) of the group C samples and 13 (21%) of group B. Only one (1.4%) of the non-thrombocytopenic samples (Group A) was positive. These data support the concept that platelet counts may be a good screening test for canine monocytic ehrlichiosis, and that the magnitude of thrombocytopenia may increase the reliability of diagnosis. Ehrlichia canis / thrombocytopenia / platelet counts / screening / PCR

Results indicated that the response to a low-dose aspirin regimen varied among healthy dogs.

Cyclosporine is an immunosuppressive agent that inhibits T-cell function by decreasing production of cytokines such as interleukin-2 (IL-2) and interferon-γ (IFN-γ). In dogs, there is currently no reliable analytical method for determining effective cyclosporine dosages in individual patients. Our laboratory has developed a quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) assay that measures IL-2 and IFN-γ gene expression, with the goal of quantifying immunosuppression in dogs treated with cyclosporine. This study focuses on analytical validation of our assay, and on the effects of sample storage conditions on cyclosporine-exposed samples. Heparinized whole blood collected from healthy adult dogs was exposed to a typical post-treatment blood concentration for cyclosporine (500 ng/ml) for 1 hour, and then stored for 0, 24, and 48 hours at both room temperature and 4°C. The study was then repeated using a cyclosporine concentration of 75 ng/ml, with sample storage for 0, 24, and 48 hours at 4°C. Cytokine gene expression was measured using RT-qPCR, and assay efficiency and inter- and intra-assay variability were determined. Storage for up to 24 hours at room temperature, and up to 48 hours at 4°C, did not significantly alter results compared to samples that were processed immediately. Validation studies showed our assay to be highly efficient and reproducible and robust enough to be feasible under standard practice submission conditions.

To date, a 4-bp deletion in the MDR1 gene has been detected in more than ten dog breeds, as well as in mixed breed dogs, in several countries, however information regarding this mutation in dogs from Brazil is lacking. For this reason, 103 Collies, 77 Border Collies, 76 Shetland Sheepdogs, 20 Old English Sheepdogs, 55 German Shepherds, 16 Australian Shepherds, and 53 Whippets from Brazil were screened for the presence of the mutation. The heterozygous mutated genotype, MDR1 (+/−), frequency found for Collies, Australian Shepherd, and Shetland Sheepdog was 50.5% (95% CI =41.1%–59.9%), 31.3% (95% CI =8.6%–53.2%), and 15.8% (95% CI =7.7%–23.9%), respectively. Homozygous mutated genotype, MDR1 (−/−), was detected only in Collies 35.9%. The MDR1 allele mutant frequency found for Collies, Australian Shepherd, and Shetland Sheepdog was 61.2% (95% CI =54.8%–67.5%), 15.6% (95% CI =3.1%–28.2%), and 7.9% (95% CI =3.7%–12.1%), respectively. Additionally, even free of the mutant allele, the maximum mutant prevalence (MMP) in that population, with 95% CI, was 3.8%, 5.2%, 5.4%, and 13.8% for Border Collies, German Shepherds, Whippets, and Old English Sheepdogs, respectively. In this way, this information is important, not only for MDR1 genotype-based breeding programs and international exchange of breeding animals of predisposed breeds, but also for modification of drug therapy for breeds at risk.

The objective of this study was to determine the frequency of different categories of specific and general classification in canine cavitary effusions (CE), as well as their association with the underlying etiologies. The laboratorial and clinical data from 304 cases of canine CE were retrospectively assessed. In 32.9% (100 cases), at least one of the specific classification categories was established, with a subtotal predominance of neoplasia (42%), bacterial serositis (24%) and hemorrhage (16%). Neoplasia was confirmed by effusion cytology in 57.5% of the cases with histopathological confirmation. From the cases in which the specific classification was not obtained, 35.8% were classified as modified transudate, 30.4% as pure transudate, 21.1% % as exudate and 12.7% was not included in any general category. The most common causes of effusion among these cases were hypoproteinemia and/or hipoalbuminemia (HPHA) (25.8%), hepatopathy (22.5%), cardiac insufficiency (15.5%) and cytologically undetected cases of neoplasia (12.4%). In conclusion, HPHA, hepatopathy and neoplasia represents important etiologies for canine CE development. Classification of effusions, solely based on [TP] and TNCC, might be an inaccurate diagnostic tool of effusions. New laboratorial classification methods for canine CE should be researched. RESUMO O objetivo deste estudo foi determinar a frequência de diferentes categorias de classificação específica e geral em efusões cavitárias (EC) caninas, bem como sua associação com as etiologias subjacentes. Os dados laboratoriais e clínicos de 304 casos de EC canina foram avaliados retrospectivamente. Em 32,9% (100 casos), pelo menos uma das categorias específicas de classificação foi estabelecida, com predomínio subtotal de neoplasia (42%), serosite bacteriana (24%) e hemorragia (16%). A neoplasia foi confirmada pela citologia da efusão em 57,5% dos casos com confirmação histopatológica. Dos casos em que a classificação específica não foi obtida (204 casos), 35,8% foram classificados como transudato modificado, 30,4% como transudato puro, 21,1% como exsudato e 12,7% não foram incluídos em nenhuma categoria geral. As causas mais comuns de efusão nestes casos foram hipoproteinemia e/ou hipoalbuminemia (HPHA) (25,8%), hepatopatia (22,5%), insuficiência cardíaca (15,5%) e casos de neoplasia citologicamente não detectados (12,4%). Em conclusão, HPHA, hepatopatia e neoplasia representam importantes etiologias para o desenvolvimento da EC canina. A classificação geral de efusões, baseada exclusivamente em proteína e celularidade, pode ser uma ferramenta diagnóstica imprecisa. Novos métodos de classificação laboratorial para ECs caninas devem ser pesquisados. Palavras-chave: líquido cavitário, exsudato, peritoneal, pleural e transudato Recebido em 18 de abril de 2018 Aceito em 4 de junho de 2018