GYROSCOPE · A multidisciplinary approach to host-shifting and invasive potential by gyrodactylid parasites

Final Activity Report Summary - GYROSCOPE (A multidisciplinary approach to host-shifting and invasive potential by gyrodactylid parasites)

This project has resulted in 17 publications (a further 15 in preparation), 16 new national and international academic collaborations, links with industry and governmental agencies, and spin-off funding for two PhD students (BBSRC/Cefas funded in Cardiff and Norwegian Research Council grant in Oslo). In addition, we have organised and hosted three international conferences showcasing the GYROSCOPE project, presented 20 conference talks and established a new internet database (GyroDb). Knowledge transfer between project partners (Cardiff, Oslo, as well as Stirling and Hull) and three associated Marie Curie Fellows has facilitated public understanding of science events and resulted in the following scientific achievements: Web-based resource (GyrodB) and host-parasite bank (GyroArc) facilitates gyrodactylid research. This project marked a new era in parasite taxonomy with the provision of http://www.gyrodb.net, a web-based resource, with interactive software for species identification. In the past gyrodactylid taxonomy has been hindered by the huge disparity in quality of descriptions, but this database increases the accuracy of species identification and diagnosis without the need for individual researchers to assemble and assimilate the diverse literature on gyrodactylids. Using specimens from GyroArC, we have utilised a combined morphological/genetic/experimental approach to describe: (a) a new gyrodactylid genus; (b) five Gyrodactylus n. spp.; (c) the reliability of gyrodactylid identification for routine governmental screening programmes and, (d) identified cryptic species in our extensive collection of field samples from Trinidad and Tobago (ca. 8,000 hosts screened for parasites). These provide excellent case studies for GyrodB, and we have demonstrated how such a facility could be extended to other taxon levels (e.g. MonodB). Host-parasite (poeciliid-gyrodactylid) system provides model for genetic and epidemiological studies. Although the ecology and behaviour of poeciliids, particularly guppies, has been studied extensively, this project is the first to focus on the parasite fauna of these fish. We confirmed gyrodactylids are the dominant parasites of Poecilia reticulata, both in ornamental (76.7% of petshop guppies infected in Europe) and wild (36.9% prevalence) stocks. One of these tropical parasite species can survive at European temperatures on native fish, posing a potential conversation threat. We also identified cryptic parasite species, co-infection interactions and complex patterns of host specificity. For instance, a common predator (Rivulus hartii) of the guppy can harbour two guppy gyrodactylids (Gyrodactylus bullaratudis and G. turnbulli), but only one parasite species thrives on the predator which may subsequently be transferred to the guppy - an unusual situation where a predator alters the parasite fauna of its prey. In a range of laboratory experiments, we showed how genetically distinct parasite strains vary in their virulence on fish stocks that also display variable resistance. Using microsatellite and MHC markers, we elucidated the reproductive mode of gyrodactylids and assessed the immunogenetics of their hosts. We also demonstrated applied applications for this system; investigating parasite control strategies and using this as a model system to assess the impact of parasites on translocation programmes utilized in conservation projects. All empirical data from the laboratory experiments contributed to development of software that predicts the outcome of infections http://www.hull.ac.uk/gyro-scope/. Finally, access to GyroArC by other researchers has facilitated international collaborations (e.g. Prof Dreyer of the Max Planck Institute completing a whole genome analysis of the guppy, and Prof. Kawata of Tohoku University in Japan, assessing Opsin gene diversity among guppies). Overall, this system is now ideally placed to address fundamental evolutionary and ecological questions about host-parasite interactions.

Data: CORDIS, © European Union