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Aspects of the biology of the parasitic copepods Lepeophtheirus salmonis and Caligus elongatus on farmed salmonids, and their treatment

Published online by Cambridge University Press:  05 December 2011

R. Wootten ,
John W. Smith  and
E. A. Needham
R. Wootten
Affiliation:
D.A.F.S. Marine Laboratory, Victoria Road, Aberdeen AB9 8DB
John W. Smith
Affiliation:
D.A.F.S. Marine Laboratory, Victoria Road, Aberdeen AB9 8DB
E. A. Needham
Affiliation:
Home Farm, Maryculter, Aberdeen
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Synopsis

The general biology and pathology of Lepeophtheirus salmonis and Caligus elongatus and the prevention and treatment of such ‘sea-lice’ infestations on farmed salmonids are described from the literature and original observations. The life-cycle of L. salmonis and probably also that of C. elongatus comprises the egg and 10 stages separated by moults, namely, two nauplius, one infective copepodite, four chalimus, two pre-adult and the adult (male and female) stages. Water temperature greatly affects the rate of development, especially for early larval stages. Heavy infestations of wild fish seem rare, and lice are lost fairly rapidly in freshwater. In Scotland at least L. salmonis shows a succession of generations on farmed salmonids; generation time is about six weeks at 9–12 C. Post-chalimus stages of C. elongatus may exchange between farmed salmonids and wild fish (especially gadoids). Epizootics (particularly with L. salmonis) cause great damage to salmonids in Norwegian and Scottish farms largely through feeding on host skin. The dermis is oedematous and haemorrhaged where lice feed, and blood seeps between scales; deaths probably result from osmoregulatory failure. Whilst prevention of infestation is difficult, a bath treatment for 1 h with 1 ppm of the organophosphorus compound Dichlorvos is effective against post-chalimus stages of L. salmonis on caged salmonids. Side effects are minimal and clearance rates from fish tissues satisfactory, but treatment may be required every 3–4 weeks.

Type
Research Article
Information
Proceedings of the Royal Society of Edinburgh, Section B: Biological Sciences , Volume 81 , Issue 3: Marine fish diseases , 1982 , pp. 185 - 197
Copyright
Copyright © Royal Society of Edinburgh 1982

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References

Ashby, A. B. 1951. Sea-lice on salmon. Period of survival in freshwater. Salm. Trout Mag. No. 131, 82–85.Google Scholar
Berger, V. Ya. 1970. [Effect of sea water of different salinities on Lepeophtheirus salmonis (Krøyer)—an ectoparasite of salmon.p] Parazitologiya 4, 136–138. [In Russian]Google Scholar
Boxshall, G. A. 1974a. The developmental stages of Lepeophtheirus pectoralis (Müller, 1776) (Copepoda: Caligidae). J. Nat. Hist. 8, 681–700.Google Scholar
Boxshall, G.A. 1974b. Infections with parasitic copepods in North Sea marine fishes. J. Mar. Biol. Ass. U.K. 54, 355–372.CrossRefGoogle Scholar
Brandal, P. O. and Egidius., E. 1977. Preliminary report on oral treatment against salmon lice, Lepeophtheirus salmonis, with Neguvon. Aquaculture 10, 177–178.CrossRefGoogle Scholar
Brandal, P. O. and Egidius, E. 1979. Treatment of salmon lice (Lepeophtheirus salmonis, Krøyer, 1838) with Neguvon — description of method and equipment. Aquaculture 18, 183–188.CrossRefGoogle Scholar
Brandal, P. O., Egidius, E. and Romslo, I. 1976. Host blood: a major food component for the parasitic copepod Lepeophtheirus salmonis, Kryeri, 1838 (Crustacea: Caligidae). Norw. J. Zool. 24, 341–343.Google Scholar
Hastein, T. and Bergsjo, T. 1976. The salmon lice Lepeophtheirus salmonis as the cause of disease in farmed salmonids. Riv. Hal. Piscic. Ittiopatol. 11, 3–5.Google Scholar
Huntsman, A. G. 1942. Death of salmon and trout with high temperature. J. Fish. Res. BdCan. 5, 485–501.CrossRefGoogle Scholar
Hutton, J. A. 1923. The parasites of salmon. Salm. Trout Mag. No. 34, 302–312.Google Scholar
Johannessen, A. 1974. Oppdrett av laksefish i Norske kystfarvann. Lakselus. Fisken Hav. Ser. B No. 2, 21–33.Google Scholar
Johannessen, A. 1978. Early stages of Lepeophtheirus salmonis (Copepoda: Caligidae). Sarsia 63, 169–176.CrossRefGoogle Scholar
Kabata, Z. 1970. Diseases of Fishes. Book 1: Crustacea as Enemies of Fishes, ed. Snieszko, S. F. and Axelrod, H. R. New Jersey: T. F. H. Publications.Google Scholar
Kabata, Z. 1972. Developmental stages of Caligus clemensi (Copepoda: Caligidae). J. Fish. Res. Bd Can. 29, 1571–1593.CrossRefGoogle Scholar
Kabata, Z. 1974. Mouth and mode of feeding of Caligidae (Copepoda), parasites of fishes, as determined by light and scanning electron microscopy. J. Fish. Res. Bd Can. 31, 1583–1588.CrossRefGoogle Scholar
Kabata, Z. 1979. Parasitic Copepoda of British Fishes. London: The Ray Society.Google Scholar
Lewis, A. G. 1963. Life history of the caligid copepod Lepeophtheirus dissimulatus Wilson, 1905 (Crustacea: Caligoida). Pacif. Sci. 17, 195–242.Google Scholar
Lundborg, L. E. and Ljungberg, O. 1977. [Attack of Caligus sp. in salmon and rainbow trout in a brackish water floating cage management.] Nord. VetMed. 29, 20–21. [In Swedish.]Google Scholar
Paperna, I/ 1975. Parasites and diseases of the grey mullet (Mugilidae) with special reference to the seas of the Near East. Aquaculture 5, 65–80.CrossRefGoogle Scholar
Rae, G. H. 1979. On the trail of the sea lice. Fish Fmr 2, 22–23, 25.Google Scholar
Templeman, W. 1967. Distribution and characteristics of Atlantic salmon over oceanic depths and on the bank and shelf slope areas off Newfoundland, March-May, 1966. ICNAF Res. Doc. 67–65, Serial No. 1856, Annual Meeting, June 1967.Google Scholar
Voth, D. R. 1972. Life history of the caligid copepod Lepeophtheirus hospitalis Fraser, 1920 (Crustacea: Caligoida). Diss. Abstr. Int. B Sci. Eng. 33, 5547–5548.Google Scholar
White, H. C. 1940. ‘Sea lice* (Lepeophtheirus) and death of salmon. J. Fish. Res. Bd Can. 5, 172–175.CrossRefGoogle Scholar
White, H. C. 1942. Life history of Lepeophtheirus salmonis. J. Fish. Res. Bd Can. 6, 24–29.CrossRefGoogle Scholar
Wootten, R., Smith, J. W. and Needham, E. A. 1977. Studies on the salmon louse, Lepeophtheirus. Bull. Off. Int. Epizoot. 87, 521–522.Google Scholar