Dispersion and toxicity to non-target crustaceans of azamethiphos and deltamethrin after sea lice treatments on farmed salmon, Salmo salar

The ecology of infectious diseases in wild and managed salmon populations is reviewed. Few pathogens have caused significant disease epidemics in the wild, and although parasites of returning adults are best documented, diseases among parr (e.g., Gyrodactylus salaris) are probably most important. The greatest diversity of parasites is known from the marine phase but few are likely to be significant pathogens, although conclusive evidence is lacking because diseased salmon cannot be tracked. The importance of stress as an immunosuppressant of fishes in degraded habitats is discussed. In addition, releases and restocking have probably also reduced the genetic disease resistance of wild fishes. We note that myxozoans, furunculosis, G. salaris, and sea lice are the pathogens most likely to threaten wild and managed salmon stocks in future. Despite abundant research on pathogens of farmed salmon, little is known of their impact on wild or managed stocks and an adequate theoretical framework for salmon disease epidemiology is urgently needed before disease becomes a limiting factor in salmon conservation.

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Sea lice (Caligidae) on wrasse (Labridae) from selected British wild and salmon-farm sources

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400059415 ◽

1992 ◽

Vol 72 (3) ◽

pp. 645-650 ◽

Cited By ~ 10

Author(s):

J. E. Bron ◽

J. W. Treasurer

Keyword(s):

Salmo Salar ◽

Host Record ◽

Sea Lice ◽

Lepeophtheirus Salmonis ◽

Fish Health ◽

Fish Farms ◽

Intensity Of Infection ◽

Farmed Salmon ◽

Goldsinny Wrasse ◽

Low Prevalence

The occurrence and intensity of infection of caligid species on the five species of wrasse commonly found in British waters are reported from twelve localities in the British Isles and from seven fish-farms in Scotland where wrasse are used to remove sea lice from salmon (Salmo salar L.). A low prevalence of infection was recorded for all wrasse species except ballan. Chalimus of Caligus centrodonti Baird were identified from fins of ballan, rock cook and goldsinny wrasse, this being the first host record for the latter two species. Single chalimus stages of Caligus elongatus Nordmann were identified from a ballan wrasse and a goldsinny wrasse and are similarly first records from these host species. No C. centrodonti were found on farmed salmon and conversely no Lepeophtheirus salmonis (Krøyer) were identified from wrasse kept in contact with infected salmon. This suggests that transfer of caligids between wrasse and salmon and vice versa does not pose problems for fish health on sea-farms.

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The poor potential of cunner, Tautogolabrus adspersus, to act as cleaner fish in removing sea lice (Caligus elongatus) from farmed salmon in eastern Canada

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f95-524 ◽

1995 ◽

Vol 52 (S1) ◽

pp. 175-177 ◽

Cited By ~ 2

Author(s):

B.M. MacKinnon

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

Sea Lice ◽

Tautogolabrus Adspersus ◽

Eastern Canada ◽

Cleaner Fish ◽

Farmed Salmon ◽

The Poor ◽

Fouling Organisms ◽

Farmed Atlantic Salmon

Cunner, Tautogolabrus adspersus, were found not to be good candidates for removal of sea lice, Caligus elongatus, from farmed Atlantic salmon (Salmo salar) during seapen trials conducted in Passamoquoddy Bay, N.B. In laboratory trials conducted in 30-gal (~136 L) glass tanks, using one cunner per infected salmon, a significant reduction in sea lice numbers was evident. In seapen trials using 30 cunner to 2000 Atlantic salmon, no significant reduction in sea lice numbers was evident after 12 weeks. Availability of fouling organisms on the seapen net may account, in part, for the lack of cleaning behaviour in these fish.

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