Reducing or
Withholding Hydrogen Peroxide Treatment during a Critical Stage of Rainbow
Trout Development: Effects on Eyed Eggs, Hatch, Deformities, and Fungal
Control
R.E. Arndt, E.J. Wagner, M.D.
Routledge-2001
North American Journal of Aquaculture, 63(2): 161-166
Abstract:
In two separate trials, eggs of rainbow trout Oncorhynchus mykiss
were cultured with the use of hydrogen peroxide and formalin treatments to
control fungal infections. For the first trial, treatment regimens consisted
of no chemical treatment (control) or daily treatments of either hydrogen
peroxide at 500 mg/L for 35 min or formalin at 1,667 mg/L for 15 min.
Hydrogen peroxide treatment duration was reduced to 5 min daily during
70–140 daily temperature units (DTU°C). In this trial, 27% of control
eggs were infected with fungus, compared with 0% for the hydrogen peroxide
and formalin treatments. Eyed egg percentages were significantly lower for
control eggs compared with the hydrogen peroxide and formalin treatments.
Comparing formalin and hydrogen peroxide treatments, percent hatch at 91%
and 90% and percent deformities at 1.0% and 1.3%, respectively, were not
significantly different. In the second trial, rainbow trout eggs were reared
from fertilization to hatch under four treatment regiments: (1) control or
no chemical treatment, (2) 500 mg hydrogen peroxide/L for 35 min daily
(hydrogen peroxide A), (3) 500 mg hydrogen peroxide/L for 35 min daily with
treatment completely withheld during 70–140 DTU°C (hydrogen peroxide B),
and (4) 1,667 mg formalin/L for 15 min daily. Within this trial 15% of
control eggs were infected with fungus, compared with 1% for hydrogen
peroxide B and 0% for both hydrogen peroxide A and formalin. Eyed egg
percentages were significantly better for hydrogen peroxide B than for
hydrogen peroxide A. Hatch was significantly reduced in the control group
compared with the formalin treatment. Incidence of deformities was not
significantly altered by treatment type.
(Utah Division of Wildlife Resources, Fisheries
Experiment Station, 1465 West 200 North, Logan, Utah 84321, USA)