• MeSH
• Bacteria klasifikace   MeSH
• interakce hostitele a patogenu * MeSH
• lidé MeSH
• mikrobiota * MeSH
• molekulární evoluce * MeSH
• paraziti mikrobiologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Overlapping distributions of hosts and parasites are critical for successful completion of multi-host parasite life cycles and even small environmental changes can impact on the parasite's presence in a host or habitat. The generalist Cardiocephaloides longicollis was used as a model for multi-host trematode life cycles in marine habitats. This parasite was studied to quantify parasite dispersion and transmission dynamics, effects of biological changes and anthropogenic impacts on life cycle completion. We compiled the largest host dataset to date, by analysing 3351 molluscs (24 species), 2108 fish (25 species) and 154 birds (17 species) and analysed the resultant data based on a number of statistical models. We uncovered extremely low host specificity at the second intermediate host level and a preference of the free-swimming larvae for predominantly demersal but also benthic fish. The accumulation of encysted larvae in the brain with increasing fish size demonstrates that parasite numbers level off in fish larger than 140mm, consistent with parasite-induced mortality at these levels. The highest infection rates were detected in host species and sizes representing the largest fraction of Mediterranean fishery discards (up to 67% of the total catch), which are frequently consumed by seabirds. Significantly higher parasite densities were found in areas with extensive fishing activity than in those with medium and low activity, and in fish from shallow lagoons than in fish from other coastal areas. For the first time, C. longicollis was also detected in farmed fish in netpens. Fishing generally drives declines in parasite abundance, however, our study suggests an enhanced transmission of generalist parasites such as C. longicollis, an effect that is further amplified by the parasite's efficient host-finding mechanisms and its alteration of fish host behaviour by larvae encysted in the brain. The anthropogenic impact on the distribution of trophically-transmitted, highly prevalent parasites likely results in a strong effect on food web structure, thus making C. longicollis an ideal bioindicator to compare food webs in natural communities versus those impacted by fisheries and aquaculture.

• MeSH
• ekosystém MeSH
• hlemýždi parazitologie   MeSH
• hostitelská specificita MeSH
• infekce červy třídy Trematoda parazitologie   přenos   veterinární   MeSH
• lidské činnosti MeSH
• měkkýši klasifikace   parazitologie   MeSH
• nemoci ptáků parazitologie   přenos   MeSH
• nemoci ryb parazitologie   přenos   MeSH
• potravní řetězec MeSH
• ptáci MeSH
• ribozomální DNA chemie   MeSH
• RNA ribozomální 28S genetika   MeSH
• rybářství MeSH
• ryby anatomie a histologie   klasifikace   MeSH
• sekvenční analýza DNA veterinární   MeSH
• stadia vývoje * MeSH
• Trematoda klasifikace   genetika   růst a vývoj   MeSH
• velikost těla MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Černé moře MeSH
• Středozemní moře MeSH

The life cycle of Hedruris spinigera Baylis, 1931 (Nematoda: Hedruridae) is determined here with the first formal identification of the parasite's intermediate host: the crustacean amphipod Paracorophium excavatum Thomson. Adult H. spinigera are redescribed from specimens collected from the stomach of fishes, Retropinna retropinna (Richardson) and Aldrichettaforsteri (Valenciennes), from Lake Waihola, New Zealand. Immature adults of the parasite collected from intermediate hosts (P. excavatum) are also described for the first time. The prevalence, abundance and intensity of infection of H. spinigera in several fish species are quantified along with the occurrence of P. excavatum, the parasite's intermediate host, in fish stomach contents. Although H. spinigera's transmission mode (trophic transmission) and fish diet potentially expose all fish species to infection, some level of host specificity must exist as parasite prevalence, abundance and intensity of infection vary greatly between potential definitive host species. We suggest here that the anatomy of the fish digestive tract and especially that of the stomach plays an important role in host suitability for H. spinigera. While P. excavatum is the only intermediate host in Lake Waihola, H. spinigera was found in six different fish species: Aldrichetta forsteri, Galaxias maculatus (Jenyns), Retropinna retropinna, Rhombosolea retiaria Hutton, Perca fluviatilis Linnaeus and Salmo trutta Linnaeus; although typical hedrurid attachment and mating positions were observed only in R. retropinna and A. forsteri. The limited distribution of H. spinigera is most likely due to that of its different host species (intermediate and definitive), all inhabitants of coastal fresh and brackish waters.

• MeSH
• Amphipoda parazitologie   MeSH
• financování organizované MeSH
• hlístice anatomie a histologie   fyziologie   MeSH
• interakce hostitele a parazita MeSH
• nemoci ryb epidemiologie   parazitologie   MeSH
• potravní řetězec MeSH
• prevalence MeSH
• ryby parazitologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Geografické názvy
• Nový Zéland MeSH

• MeSH
• finanční podpora výzkumu jako téma MeSH
• hlístice klasifikace   parazitologie   MeSH
• krabi parazitologie   MeSH
• nematodózy parazitologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Geografické názvy
• Nový Zéland MeSH

• MeSH
• bludiště - učení MeSH
• Hymenolepis MeSH
• krysa rodu rattus parazitologie   psychologie   MeSH
• moč chemie   MeSH
• odoranty MeSH
• parazitemie MeSH
• testosteron krev   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus parazitologie   psychologie   MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• srovnávací studie MeSH