Rach, J.J., T. M. Schreier, S. M. Schleis, and M.P. Gaikowski.   2003.  Efficacy of hydrogen 
peroxide to control fungus (saprolegniasis) on channel catfish eggs (Ictalurus punctatus). 
Submitted to the U.S. Food and Drug Administration Center for Veterinary Medicine, February 
2003.   149 pp.



A clinical field trial was conducted at the Missouri Department of Natural Resources Lost 
Valley Fish Hatchery  (Warsaw, Missouri) to evaluate the efficacy of hydrogen peroxide 
to control mortality associated with saprolegniasis in channel catfish eggs.   The study 
design consisted of two trials: (1) trial one consisted of nine egg jars (0, 500, and 750 
mg/L treatment groups) containing eggs in the natural gelatin matrix, and (2) trial two 
consisted of six egg jars (0 and 500 mg/L treatment groups) containing individual eggs 
that had the gelatin matrix dissolved with sodium sulfite.  Each treatment group was 
tested in triplicate.  Fifteen-minute flow-through hydrogen peroxide treatments (six total) 
of 0 (untreated control), 500, or 750 mg/L were applied daily (one treatment per day) 
through hatch (June 21-26, 2002).  Hydrogen peroxide concentrations were verified for 
each treatment on water samples removed from each egg jar approximately 5 min before 
treatment termination.  The efficacy of a treatment regimen was determined by the 
number of fry that hatched.  Mean percent hatch in trial 1(eggs in matrix) was 44 
(control), 54 (500 mg/L), and 69% (750 mg/L).  Hydrogen peroxide treatment at 500 and 
750 mg/L significantly increased the probability of hatch compared to the untreated 
control group, (P<0.01).  In trial 2 (gelatin matrix removed from eggs), the mean percent 
hatch was 57 (control) and 67 (500 mg/L).  The probability of hatch of channel catfish 
eggs in trial 2 was significantly increased (P<0.01) by hydrogen peroxide treatments of 
500 mg/L in comparison to the untreated controls.  Hydrogen peroxide was effective in 
controlling mortality and increasing percent hatch of channel catfish eggs incubated 
either in the gelatin matrix or without the matrix in comparison to the untreated control.