| Abstract [eng] |
Avian malaria parasites are responsible for severe diseases in some domestic and wild birds. These parasites are cosmopolitan in distribution; they are widespread in Europe, including the Baltic region. A peculiarity of current studies of avian Plasmodium species is that information about ecology, distribution, prevalence and other aspects of their biology has been accumulated using free-living birds. To elucidate the significance of malaria infections and their impact on host fitness, behaviour, sexual selection and parasite-host co-evolution, experimental information about Plasmodium spp. virulence, specificity and dynamics of parasitemia in different avian hosts is crucial. Unfortunately such studies remain uncommon. The objective of this study was to obtain new field and laboratory experimental data about the biology of avian malaria parasites and to link PCR-based information with data from traditional parasitology. It was demonstrated that prevalence of avian malaria and other haemosporidian parasites is estimated equally well by microscopy and currently used nested PCR-based methods. Both methods have advantages and disadvantages. So we encourage using both these tools in parallel during studies of haemosporidians. Lineages for molecular identification of P. relictum (lineage SGS1) and P. circumflexum (TURDUS1) were determined, also new methods of single cell dissection, DNA extraction and PCR-based analysis of avian malaria and closely related blood parasites were developed. During experimental investigation, was shown that the susceptibility of different passerine birds to the same lineage of malaria parasites is markedly different, and that the same parasite lineage can cause malaria of different severity even in phylogenetically closely related bird species. Later, during treatment of the birds was estimated that the antimalarial drug Malarone™ is non-toxic for birds and is effective against blood stages of avian Plasmodium spp. The geographic distribution of P. relictum lineages SGS1 and GRW11 in the house sparrow was determined. |
