Expanding the known haemosporidian parasite diversity in Eurasian Bluethroat (Luscinia svecica) subspecies through amplicon sequencing
Description
Monitoring haemosporidian parasites in birds is essential for comprehending the dynamics of avian malaria, a disease that significantly affects bird populations worldwide. This study concentrated on the prevalence and diversity of haemosporidian parasites in 1989 specimens from two subspecies of the Eurasian bluethroat (Luscinia svecica), aiming to explore the genetic diversity and species richness of haemosporidian lineages fauna across the host populations. By utilizing next-generation (NGS) amplicon high-throughput sequencing, we observed a marked increase in the detection of haemosporidian diversity, revealing cryptic lineages variants and species previously unidentified by Sanger sequencing. A high prevalence of the Plasmodium haplotypes was seen in all studied sites, accompanied by a less frequent Leucocytozoon infection in the red-spotted subspecies and minimal occurrence of Haemoproteus lineages. Both the previously known lineages and new, low-prevalence cryptic lineages variants were detected, underscoring the complexity of haemosporidian infections in avian hosts. The use of species delimitation tools provided a detailed understanding of haemosporidian species diversity, their coexistence within hosts, and their phylogenetic relationships. Despite the varying ecological characteristics of the study sites, no significant difference in haemosporidian alpha diversity among populations was found. However, significant differences in beta diversity were identified, suggesting that habitat characteristics and geographic distance influence parasite distribution. These findings highlight the importance of advanced molecular techniques in revealing the hidden diversity of parasites, offering valuable insights into the ecology and evolution of haemosporidian infections. Given the threatened status of one of the host’s populations, knowledge on local diversity of haemosporidian parasites also has implications for possible conservation strategies.