Parasites - Myxozoans

The Parasitology Group has a continuing programme of research into these enigmatic parasites and a number of species have been studied. A major focus of interest is Sphaerospora truttae, a common pathogen of salmonids in Scotland. This species has been used as a model for life-cycle and epidemiological studies. The life-cycles of several myxozoans have been shown to involve a fish and an invertebrate host, commonly an annelid, and research has been broadened in order to investigate the various myxozoans occurring in both hosts in an enzootic habitat. Molecular and experimental techniques, including in-situhybridisation, are used to determine life-cycles and development in the hosts. Communities of myxosporeans in cultured fish are also investigated to assess their contribution to morbidity, mortality and overall performance under culture conditions. Of particular interest are  myxosporean infections of maricultured fish although little is known of  life-cycles in the marine environment. Molecular data are also used for phylogenetic analysis of the different species in order to contribute to the currently confused systematics of this taxon.

Selected References

  1. Holzer, A.S., Wootten, R. & Sommerville, C. (2007) The secondary structure of the unusually long 18S ribosomal RNA of the myxozoan Sphaerospora truttae and structural evolutionary trends in the Myxozoa. International Journal for Parasitology, 37 (11), 1173-1296.
  2. Holzer, A.S., Sommerville, C. & Wootten, R. (2006) Molecular studies on the seasonal occurrence and development of five myxozoans in farmed Salmo trutta L. Parasitology, 132, 193-205.
  3. Holzer, A.S., Sommerville, C. & Wootten, R. (2005) Molecular identity, phylogeny and life-cycle of Chloromyxum schurovi Shul’man & Ieshko 2005. Parasitology Research, 99 (1), 90-96.
  4. Holzer, A.S., Sommerville, C. and Wootten, R. (2003) Tracing the route of Spheraerospora truttae from the entry locus to the target organ of the host, Salmo salar L., using an optomized and specific in situ hybrdization technique. Journal of Fish Diseases, 26, 647-655.
  5. Ozer, A., Wootten, R. & Shinn, A.P. (2002) Infection prevalence (%) seasonality and host specificity of actinosporean types in Atlantic salmon fish farms in Northern Scotland. Folia Parasitologica, 49, 263-268.
  6. Ozer, A., Wootten, R. & Shinn, A.P. (2002) Survey of actinosprean types (Myxozoa) belonging to seven collective groups found in freshwater salmon farms in Northern Scotland. Folia Parasitologica, 49, 189-210
  7. McGeorge, J., Sommerville, C. & Wootten, R. (1997) Studies of actinosporean myxozoan stages parasitic in oligochaetes from the sediments of a hatchery where Atlantic salmon harbour Sphaerospora truttae infection. Diseases of Aquatic Organisms, 30, 107–119.
  8. Lom, J., McGeorge, J., Feist, S.W., Morris, D. & Adams, A. (1997) Guidelines for the uniform characterisation of the actinosporean stages of parasites of the phylum Myxozoa. Diseases of Aquatic Organisms, 30 (1), pp.1-9.
  9. McGeorge, J., Sommerville, C. & Wootten, R. (1996) The epizootiology of Sphaerospora truttae (Myxozoa: Myxosporea) infections of Atlantic salmon, Salmo salar L. at freshwater smolt producing hatcheries in Scotland. Diseases of Aquatic Organisms, 26, 33-41.
  10. McGeorge, J., Sommerville, C. & Wootten, R. (1996) Transmission experiments to determine the relationship between Sphaerospora sp. from Atlantic salmon, Salmo salar, and Sphaerospora truttae: a revised species description for S.truttae. Folia Parasitologica, 43, 107-116.
  11. McGeorge, J., Sommerville, C. & Wootten R. (1994) Light and electron microscope observations on extrasporogonic and sporogonic stages of the genus Sphaerospora Thelohan, 1892 from Atlantic salmon, Salmo salar L., in Scotland. Journal of Fish Diseases, 17, 227-238
  12. Athanassopoulou, F. & Sommerville, C. (1993) The significance of myxosporean infections in roach in different habitats. Journal of Fish Diseases, 16 (1), 39-53.
  13. Athanassopoulou, F. & C. Sommerville (1993) A comparative study of the parasites of Myxidium rhodei Leger 1905 and Myxidium pfeifferi Auerbach 1908 in roach. (Rutilus rutilus L). Journal of Fish Diseases, 16 (1), 27-39.