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Population biology of Pomphorhynchus laevis in brown trout from two lakes in the west of Ireland

Published online by Cambridge University Press:  05 June 2009

S. Molloy
Affiliation:
Department of ZoologyTrinity College, Dublin 2, Ireland
C. Holland*
Affiliation:
Department of ZoologyTrinity College, Dublin 2, Ireland
M. O'Regan
Affiliation:
Department of Statistics, Trinity College, Dublin 2, Ireland
*
* Author for correspondence

Abstract

Since Ireland is the only country in which Pomphorhynchus laevis (Acanthocephala) uses brown trout (Salmo trutta) as its preferred definitive host, the population biology of the parasite in this host was investigated thus enabling a comparison to be made with data collected on P laevis from other hosts, particularly the cyprinids, chub and barbel. Over a period of 12 months, 549 brown trout were caught from two lakes, Lough Feeagh and Bunaveela Lake, in the Burrishoole River system, Co. Mayo, Ireland. The parasite component community was dominated by a single species, P laevis. Fifty eight percent of the trout sample were infected with the acanthocephalan and the mean abundance (± SD) was 3.1 ± 5.1. The relationships between the prevalence and abundance of P laevis and season and site of host capture and host age and sex were explored. As single factors none of these parameters emerged as significant contributors to changes in parasite abundance although some interaction terms proved to the significant. A random sample of over 700 P laevis parasites were subjected to further investigation and their size, position in the intestine and maturity status are described. Parasites attained an average weight of 7 mg and occupied the posteriad positions within the fish intestine (77%). Parasites from this sample of Irish brown trout attained a similar average size to those found in chub and barbel from England. 42.3% of the total parasites examined contained ovarian balls only and 17% contained fully mature acanthors. Therefore only a moderate proportion of female worms contained mature acanthors in these trout whereas the majority of worms recovered from a sample of chub were gravid. Utilizing a logistic regression model, parasite size, season, and site of host capture emerged as particularly significant factors which contribute to whether a parasite contains mature eggs.

Type
Research Papers
Copyright
Copyright © Cambridge University Press 1995

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References

Anderson, R.M. & Gordon, D.M. (1982) Processes influencing the distribution of parasite numbers within host population with special emphasis on parasite-induced host mortalities. Parasitology 85, 373398.CrossRefGoogle ScholarPubMed
Awachie, J.B.E. (1965) The ecology of Echinorhynchus truttae in a trout stream in North Wales. Parasitology 55,747762.Google Scholar
Bates, R.M. & Kennedy, C.R. (1990) Interactions between the acanthocephalansPomphorhynchus laevis and Acanthocephalus anguillae in rainbow trout: testing an exclusion hypothesis. Parasitology 100, 435444.Google Scholar
Brown, A.F. (1989) Seasonal dynamics of the acanthocephalan Pom phorhynchus laevis (Muller, 1776) in its intermediate and preferred definitive hosts. Journal of Fish Biology 34, 183194.Google Scholar
Brown, A.F., Chubb, J.C. & Veltkamp, C.J. (1986) A key to the species of Acanthocephala parasitic in British freshwater fishes. Journal of Fish Biology 28, 327334.Google Scholar
Conneely, J.J. & McCarthy, T.K. (1983) The metazoan parasites of freshwater fishes in the Corrib catchment area, Ireland. Journal of Fish Biology 24, 363375.Google Scholar
Fitzgerald, R.D. & Mulcahy, M.F. (1983) Parasites of salmon Salmo salar L. and trout Salmo trutta L. in the River Shournagh. Irish Fisheries Investigations Series A 23, 2431.Google Scholar
Hine, P.M. & Kennedy, C.R. (1974) The population biology of the acanthocephalan Pomphorhynchus laevis (Muller) in the River Avon. Journal of Fish Biology 6, 665679.Google Scholar
Kane, M.B. (1966) Parasites of Irish fishes. Scientific Proceedings of the Royal Irish Academy B1, 205220.Google Scholar
Kennedy, C.R. (1972) The effects of temperature and other factors upon the establishment and survival of Pomphorhynchus laevis (Acanthocephala) in goldfish, Carassius auratus. Parasitology 65, 283294.Google Scholar
Kennedy, C.R. (1974) A checklist of British and Irish freshwater fish parasites with notes on their distribution. Journal of Fish Biology 6, 613644.Google Scholar
Kennedy, C.R. (1984) The status of flounders, Platichthys flesus L., as hosts of the acanthocephalan Pomphorhynchus laevis and its survival in marine conditions. Journal of Fish Biology 24, 135149.CrossRefGoogle Scholar
Kennedy, C.R. & Moriarty, C. (1987) Co-existence of congeneric species of Acanthocephala: Acanthocephalus lucii and Acanthocephalus anguillae in eels Anguilla anguilla in Ireland. Parasitology 95, 301310.Google Scholar
Kennedy, C.R.& Rumpus, (1977) Long term changes in the size of the Pomphorhynchus laevis (Acanthocephala) population in the River Avon. Journal of Fish Biology 10,3542.Google Scholar
Kennedy, C.R., Broughton, P.F. & Hine, P.M. (1976) The sites occupied by the acanthocephalan Pomphorhynchus laevis in the alimentary canal of fish. Parasitology 72, 195206.Google Scholar
Kennedy, C.R., Broughton, P.F. & Hine, P.M. (1976) The status of brown and rainbow trout, Salmo trutta and Salmo gardneri as hosts of the acanthocephalan Pomphorhynchus laevis. Journal of Fish Biology 13, 265275.Google Scholar
Kennedy, C.R., Bates, R.M. & Brown, A.F. (1989) Discontinuous distributions of the fish acanthocephalans Pomphorhynchus laevis and Acanthocephalus anguillae in Britain and Ireland: and hypothesis. Journal of Fish Biology 34, 607619.Google Scholar
Margolis, L., Esch, G.W., Holmes, J.C., Kuris, A.M. & Schad, G.A. (1982) The use of ecological terms in parasitology (report of an ad hoc committee of the American Society of Parasitologists). Journal of Parasitology 68, 131133.CrossRefGoogle Scholar
Molloy, S.M., Holland, C.V. & Poole, R. (1993) Helminth parasites of brown trout and sea trout Salmo trutta L. from the west coast of Ireland. Biology and Environment 93B, 137142.Google Scholar
Molloy, S.M., Holland, C.V.& Poole, R. (1995) Parasite community structure in brown trout from two lakes in the west of Ireland. Journal of Helminthology (in press).Google Scholar
Moravec, F. & Scholz, T. (1991) Observations on the biology of Pomphorhynchus laevis (Zoega in Muller, 1776) (Acanthocephala) in the Rokytna River, Czech and Slovak Federative Republic. Helminthologia 28, 2329.Google Scholar
Munro, M.A., Whitfield, P.J. & Diffley, R. (1989) Pomphorhynchus laevis (Muller) in the flounder, Platichthys flesus L., in the tidal river Thames: population structure, microhabitat utilization and reproductive status in the field and under laboratory conditions. Journal of Fish Biology 35, 719735.Google Scholar
Munro, M.A., Reid, A. & Whitfield, P.J. (1990) Genomic divergence in the ecologically differentiated English freshwater and marine strain of Pomphorhynchus laevis (Acanthocephala: Palaeacanthocephala): a preliminary investigation. Parasitology 101, 451454.Google Scholar
Pennycuick, L. (1971) Seasonal variations in the parasite infections in a population of three-spined sticklebacks, Gasterosteus aculeatus L. Parasitology 63, 373388.Google Scholar
Polyanski, Yu.I. (1955) Contributions to the parasitology of the fishes of the northern seas of the USSR. Trudy Zoologicheskogo Instituta Leningrad 19, 5170.Google Scholar