control group was 50.0%. Statistical comparisons performed on the 10% infected
treatment groups showed that the 500 ~1 l- ’ hydrogen peroxide treatment was
significantly different from the positive control and the 100 ~1 1-l treatment. The 500
~1 1-l hydrogen peroxide treatment was the most effective at controlling the spread of
fungus and improving the hatch.
No significant difference in final infection rate or percent hatch was seen among all
concurrent treatments of 1500 ~1 1-l formalin, 1000 ~1 1-l hydrogen peroxide, and
30000 mg 1-l salt treatment groups for uninfected eggs (mean range 86.6-90.6%, Table
3). The concurrent treatments on eggs with 10% fungal infection indicated that all three
fungicides significantly improved the hatching success in comparison with the positive
control. Formalin (1500 ~1 l- ’ ) and hydrogen peroxide (1000 ,ul l- ’ > appeared to be the
most effective based on mean percent hatch of 73.5% and 68.3%, respectively. These
chemicals controlled the spread of fungus to healthy eggs (mean final fungal infection
rates of 26.1% and 29.0%, respectively). Sodium chloride was not as effective as the
other chemicals and provided a mean percent hatch of 60.3% (mean final infection rate
of 41.3%). The mean hatch for the positive control was 27.3% and the mean final
infection rate was 67.9%.
Analyses of water samples to determine actual chemical treatment concentrations
were conducted for all efficacy tests. Mean treatment concentrations measured ranged
from 100.4 to 117.3% of expected values (Table 1, Table 2, and Table 3).