| 1. |
- Brattström, Oskar, et al.
(författare)
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Geographic origin and migration phenology of European red admirals (Vanessa atalanta) as revealed by stable isotopes
- 2018
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Ingår i: Movement Ecology. - : Springer Science and Business Media LLC. - 2051-3933. ; 6:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Long-distance migration has evolved multiple times in different animal taxa. For insect migrants, the complete annual migration cycle covering several thousand kilometres, may be performed by several generations, each migrating part of the distance and reproducing. Different life-cycle stages and preferred orientation may thus, be found along the migration route. For migrating red admirals (Vanessa atalanta) it has been questioned if they reproduce in the most northern part of the range. Here we present migration phenology data from a two-year time series of migrating red admirals captured at Rybachy, Kaliningrad, in the northern part of Europe investigating time for migration, life-history stage (migration, reproduction) as well as site of origin in individual butterflies. Methods: Red admirals were captured daily at a coastal site during spring, summer and autumn in 2004 and 2005. For the sampled individuals, reproductive status and fuel content were estimated by visual inspection, and hydrogen isotopes (δ 2H) were analysed in wing samples. δ 2H values was compared with samples from two nearby reference sites in Estonia and Poland. Results: Analysis of hydrogen isotopes (δ 2H) in red admiral wings showed that the spring cohort were of a southerly origin, while those caught in August or later in the autumn were from the local region or areas further to the north. All females caught during spring had developing eggs in their abdomen, but no eggs were found in late summer/autumn. There was a male-biased sex ratio during autumn and a difference in lipid content between years. When comparing the isotopic data with inland nearby locations, it was clear that the range of δ 2H values (- 181 to - 78) was wider at Rybachy as compared to the two reference sites in Estonia and Poland (- 174 to - 100). Conclusions: During spring, migratory female red admirals arrived from the south and were ready to reproduce, while the autumn passage mainly engaged local and more northern individuals carrying large fuel deposits in preparation for long-distance migration. The phenology data suggest that individuals select to migrate in favourable weather conditions and that numbers may differ between years. Future studies should focus on individual sampling at a wide range of sites to reveal differential migration strategies and timing of migration between sexes and populations of migrating butterflies.
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| 2. |
- Dimitrov, Dimitar, et al.
(författare)
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Plasmodium spp.: An experimental study on vertebrate host susceptibility to avian malaria.
- 2015
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Ingår i: Experimental Parasitology. - : Elsevier BV. - 0014-4894. ; 148, s. 1-16
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Tidskriftsartikel (refereegranskat)abstract
- The interest in experimental studies on avian malaria caused by Plasmodium species has increased recently due to the need of direct information about host-parasite interactions. Numerous important issues (host susceptibility, development of infection, the resistance and tolerance to avian malaria) can be answered using experimental infections. However, specificity of genetically different lineages of malaria parasites and their isolates is largely unknown. This study reviews recent experimental studies and offers additional data about susceptibility of birds to several widespread cytochrome b (cyt b) lineages of Plasmodium species belonging to four subgenera. We exposed two domesticated avian hosts (canaries Serinus canaria and ducklings Anas platyrhynchos) and also 16 species of common wild European birds to malaria infections by intramuscular injection of infected blood and then tested them by microscopic examination and PCR-based methods. Our study confirms former field and experimental observations about low specificity and wide host-range of Plasmodium relictum (lineages SGS1 and GRW11) and P. circumflexum (lineage TURDUS1) belonging to the subgenera Haemamoeba and Giovannolaia, respectively. However, the specificity of different lineages and isolates of the same parasite lineage differed between species of exposed hosts. Several tested Novyella lineages were species specific, with a few cases of successful development in experimentally exposed birds. The majority of reported cases of mortality and high parasitaemia were observed during parasite co-infections. Canaries were susceptible mainly for the species of Haemamoeba and Giovannolaia, but were refractory to the majority of Novyella isolates. Ducklings were susceptible to three malaria infections (SGS1, TURDUS1 and COLL4), but parasitaemia was light (<0.01%) and transient in all exposed birds. This study provides novel information about susceptibility of avian hosts to a wide array of malaria parasite lineages, outlining directions for future experimental research on various aspects of biology and epidemiology of avian malaria.
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| 3. |
- Palinauskas, Vaidas, et al.
(författare)
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Comparison of mitochondrial cytochrome b lineages and morphospecies of two avian malaria parasites of the subgenera Haemamoeba and Giovannolaia (Haemosporida : Plasmodiidae)
- 2007
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Ingår i: Zootaxa. - 1175-5334. ; :1626, s. 39-50
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Tidskriftsartikel (refereegranskat)abstract
- PCR-based methods have been increasingly used in diagnosis of parasitic diseases. Over 40 morphospecies of avian malaria parasites of the genus Plasmodium have been described. However, only nine of them have been identified on the level of their mitochondrial cytochrome b (cyt b) gene lineages, which are frequently used in molecular biology studies of avian blood haemosporidian parasites. In this study, we linked two common mitochondrial cyt b lineages P-SGS1 and P-TURDUS1 with their morphospecies. Light infections with two species of malaria parasites of the subgenera Haemamoeba and Giovannolaia were isolated from naturally infected adult Hawfinches, Coccothraustes coccothraustes Linnaeus, on the Curonian Spit in the Baltic Sea. These parasites were inoculated to naive juveniles of the Common Crossbill, Loxia curvirostra Linnaeus, and House Sparrow, Passer domesticus Linnaeus. Heavy parasitemia of Plasmodium (Haemamoeba) relictum Grassi & Feletti, 1891 ( lineage P-SGS1) and Plasmodium (Giovannolaia) circumflexum Kikuth, 1931 (P-TURDUS1) developed in the subinoculated Common Crossbills and House Sparrows, respectively, which enabled the detailed illustration of all main blood stages of these parasites and the deposition of their voucher specimens. The parasites of both lineages are actively transmitted in Europe and inhabit a broad range of avian hosts. Lineages closely related to P. relictum and P. circumflexum were identified. This study contributes to establishing of combined PCR-based and morphological identification of avian malaria parasites.
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