1 DECEMBER 1999
Sent: October 25, 1999
From: Robert Blyth <rblyth@liverpool.ac.uk>
To: <AQUA-L@killick.ifmt.nf.ca>
QUESTION:
I have a number of weaned Dover sole (Solea solea) juveniles (0.5g-2g) that were generally feeding very well. However, for a couple of months they've had chronic problems of weakness, fin rot and tail necrosis, together with sloughing of skin, all leading to death a couple of days later. Histology and plating of skin scrapes has shown nothing out of the ordinary. Has anybody else had similar problems, or has anybody got any ideas for treatment? Our standard treatments (UV'ing and charcoal filtering the inflow, freshwater baths, reduced salinity rearing, regular tank changes, formalin, OTC, etc) haven't made any difference.
I also have a number of other flat and round fish species
which have apparently been unaffected.
Rob Blyth
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COMMENTS 1:
Is this not caused by a ciliate infection? Our Solea larvae have been affected by a ciliate eating parts of the fins and tail when they were app. 2 months old.
We subjected the fish to an acriflavine (5 ppm) treatment. The
treatment was very effective and all ciliates disappeared from the system after 4 days.
Philippe Dhert
Lab. of Aquaculture & Artemia Reference Center.
Rozier 44
B9000 Gent
Belgium
E-mail: philippe.dhert@rug.ac.be
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COMMENTS 2:
Was there any observation of cannibalism? Irrespective, don't overlook nutritional deficiencies/requirements. A lot of the flatfish people have looked at various fatty acid components which play an important part in general overall health and hardiness issues. Stress
triggers a lot of other problems as well and nutritional elements may highly contribute to stress management.
Leland
E-mail: owner-AQUA-L/OU=fisheries@mi.mun.ca
www.aquafauna.com