Predicting the distribution of Ixodes ricinus and Dermacentor reticulatus in Europe: a comparison of climate niche modelling approaches.

BackgroundThe ticks Ixodes ricinus and Dermacentor reticulatus are two of the most important vectors in Europe. Climate niche modelling has been used in many studies to attempt to explain their distribution and to predict changes under a range of climate change scenarios. The aim of this study was to assess the ability of different climate niche modelling approaches to explain the known distribution of I. ricinus and D. reticulatus in Europe.MethodsA series of climate niche models, using different combinations of input data, were constructed and assessed. Species occurrence records obtained from systematic literature searches and Global Biodiversity Information Facility data were thinned to different degrees to remove sampling spatial bias. Four sources of climate data were used: bioclimatic variables, WorldClim, TerraClimate and MODIS satellite-derived data. Eight different model training extents were examined and three modelling frameworks were used: maximum entropy, generalised additive models and random forest models. The results were validated through internal cross-validation, comparison with an external independent dataset and expert opinion.ResultsThe performance metrics and predictive ability of the different modelling approaches varied significantly within and between each species. Different combinations were better able to define the distribution of each of the two species. However, no single approach was considered fully able to capture the known distribution of the species. When considering the mean of the performance metrics of internal and external validation, 24 models for I. ricinus and 11 models for D. reticulatus of the 96 constructed were considered adequate according to the following criteria: area under the receiver-operating characteristic curve > 0.7; true skill statistic > 0.4; Miller's calibration slope 0.25 above or below 1; Boyce index > 0.9; omission rate ConclusionsThis comprehensive analysis suggests that there is no single 'best practice' climate modelling approach to account for the distribution of these tick species. This has important implications for attempts to predict climate-mediated impacts on future tick distribution. It is suggested here that climate variables alone are not sufficient; habitat type, host availability and anthropogenic impacts, not included in current modelling approaches, could contribute to determining tick presence or absence at the local or regional scale

Dogs babesiosis - still actually problem

Babesiosis (piroplasmosis) is a tick−borne disease with a symptoms of hemolytic anemia. For the first time babesiosis was described in dogs in United States in 1934. The etiological factor of this disease in Poland is protozoa Babesia canis, and its vector – Dermacentor−tick. The most common symptoms of babesiosis are: icterus, hemoglobinuria, occasionally vomits and diarrhea. The biochemical examination of blood serum from sick animals can reveal the increase of activity of AST, ALT, the increase of total bilirubine, urea and creatynine concentrations. The results of hematological examinations can show anemia, leucopenia and thrombocytopenia. The diagnosis of babesiosis bases on anamnesis, clinical examinations of dogs, microscopical examinations of blood smears from sick animals; IF−assay and PCR can also be helpful for the diagnosis of babesiosis. Till now does not exist the effective immunoprophylaxis against this disease. Babesiosis is well−known disease, however there are still problems with therapy of infected animals. Most effective drug in therapy of dog piroplasmosis is imidocarb, but sometimes can be observed side effects after it application. It is possible that the genetically differences which are detected in subspecies may have an influence on the severity of disease and the effectiveness of therapy

Identyfikacja piroplazm izolowanych od koni w Polsce w klinicznych przypadkach choroby

The study was aimed at determining the cause of the diseases in three horses exhibiting symptoms of fever, ataxia, mucus membrane paleness, haematuria and thrombocytopenia. The PCR technique revealed the presence in the blood of 18S RNA Babesia/Theileria spp. genetic material. DNA amplification using primers RLB F2 and RLB R2 produced 430 bp size products. The sequences of these PCR products demonstrated a 95.6–97.5% similarity with the sequence of the fragment of 18S RNA Babesia equi, gene number DQ287951 in the GenBank. The treatment utilizing the subcutaneous application of the imidocarb resulted in gradual recovery of the diseased animals