Efficacy of hydrogen
peroxide to control mortalities associated with bacterial gill disease
infections on hatchery-reared salmonids
J.J. Rach,
M.P. Gaikowski,
R.T. Ramsay-2000
Journal of Aquatic Animal Health, 12(2) : 119-127
(from Current Contents)
Abstract :
The efficacy of hydrogen peroxide to control
mortalities associated with bacterial gill disease (BGD) was evaluated in
three trials conducted at two Wisconsin Department of Natural Resources
hatcheries. Microscopic examination of the fish gills before treatment
revealed gill damage and the presence of bacteria indicative of BGD. In
separate trials, brown trout Salmo trutta, chinook salmon Oncorhynchus
tshawytscha, and rainbow trout O. mykiss were exposed to hydro en peroxide
concentrations of 0, 56, 110, or 230 mg/L for 30 or 60 min every other day.
In all three trials, at least one of the hydrogen peroxide treatment
regimens reduced cumulative fish mortality in comparison with the controls.
Exposures of 230 mg/L for 60 min increased the risk of mortality in brown
trout and chinook salmon relative to that at other treatment concentrations.
Exposures of up to 230 mgn for 30 min decreased the risk of mortality in
rainbow trout. Posttreatment qualitative gill examination indicated that
gills of the treated fish appeared normal, whereas the gills of control fish
exhibited pale coloration, clubbing of filaments, and lamellar fusion. On
the basis of the efficacy data, two static bath treatment regimens were
effective in the control of BGD: hydrogen peroxide administered at
concentrations of 56-110 mg/L as a 60-min exposure or hydrogen peroxide
administered at concentrations of 56-230 mg/L as a 30-min exposure.
(US Geol Survey, Upper Midwest Environm Sci Ctr, 2630
Fanta Reed Rd, La Crosse, WI 54603, USA, e-mail : jeffrey_rach@usgs.gov)
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