Rach, J.J. and M.P. Gaikowski.  1998.  Efficacy and safety of hydrogen peroxide to control and 
prevent fungal infections cold-, cool- and warm-water fish eggs.  Fisheries and Aquatic 
Resources Program Review of the USGS Biological Resources Division, Madison, WI, August 
11-12.

Abstract- Fish eggs were cultured in miniature egg jars and treated with hydrogen peroxide using 
methods similar to those used in fish hatcheries.  Fifteen minute hydrogen peroxide treatments 
were administered every weekday (Monday-Friday) to rainbow trout, northern pike, yellow 
perch, lake sturgeon, common carp, channel catfish, walleye, white sucker, and paddlefish eggs 
to determine the safety and efficacy of the standard egg treatment (500 無/L for 15 min).
Safety-  For all of the cool- and warmwater species tested, the mean percent hatch was greater in 
eggs treated with 1,000 無/L hydrogen peroxide for 15 minutes than in the untreated controls.  
Hydrogen peroxide concentrations of > 3,000 無/L could be safely administered to northern pike, 
yellow perch, lake sturgeon, common carp, and channel catfish eggs.  Eggs of walleye, white 
sucker, and paddlefish could be safely treated with hydrogen peroxide concentrations of greater 
than 1,000 and less than 3,000 無/L.  Common carp, lake sturgeon, and paddlefish were the least 
sensitive to hydrogen peroxide with percent hatches ranging from 40 to 48 percent in the 6,000 
無/L treatment.
Efficacy-  Fungal infections reduced or eliminated the hatch of most cool- and warmwater 
control eggs whereas nearly all treated cool- and warmwater eggs remained free of infection. The 
increased percent hatch and the lack of fungus on cool- and warmwater eggs receiving treatments 
indicated that hydrogen peroxide was effective in inhibiting fungal growth on fish eggs of all 
cool- and warmwater species tested, except lake sturgeon (fungus present in all test groups) and 
northern pike (no fungus present in any of the test groups). 
Sensitivity-  Daily percent mortality of rainbow trout eggs increased significantly between days 6 
and 10 (78 to 135 Daily Temperature Units ?C) of incubation.  Discontinuing hydrogen peroxide 
treatments to rainbow trout eggs from day 7 to day 11 (78 to 105 DTU ?C) of incubation 
significantly increased the probability of eggs reaching the eyed egg stage.  The mean percent 
hatch of rainbow trout eggs treated with hydrogen peroxide at concentrations up to 1,000 無/L 
may be increased if no treatments are administered between 70 to 140 DTU ?C.
      When fungal infections are established on fish eggs, hydrogen peroxide treatments of 
1,000 無/L may provide better control of fungus than the current standard treatment.  However, 
egg sensitivity is likely to vary with species, strain, and the unique environmental conditions at 
each facility, therefore, other species and strains not previously tested should be initially treated 
with hydrogen peroxide at 500 無/L until monitoring of egg mortality identifies the presence or 
absence of a sensitive period.