Egg disinfection is considered the most important
routine work in hatcheries to avoid fungal and/or
bacterial infection of fish eggs. The aim of this study
was to determine the effectiveness of three disinfectants:
formalin, iodine and sodium chloride on the
hatching success of yellow perch eggs. The disinfectants
were tested in triplicate at different concentrations
for 15 and 30 min bath treatments. Two
experiments were conducted; formalin at five concentrations
(25, 50, 100, 150 and 200 mg L1)
and 25 mg L1 iodine were tested in the first
experiment. The second experiment involved formalin
at three concentrations (250, 500 and
1000 mg L1), iodine at three concentrations (50,
100 and 250 mg L1) and sodium chloride at
three concentrations (500, 1000 and
3000 mg L1) were used. Iodine and sodium chloride-
treated eggs hatched earlier than formalintreated
eggs. The highest mean percentage of eyed
stage, hatching rate and survival to first feeding fry
was observed at 200 mg L1 formalin for 30 min,
50 mg L1 iodine for 15 min and 500 mg L1
sodium chloride for 30 min. High concentrations of
formalin (1000 mg L1), iodine (250 mg L1) and
sodium chloride (1000 and 3000 mg L1) showed
toxicity to yellow perch eggs, resulting in low
hatching rate and survival to first feeding fry. We
recommended formalin at a concentration of 150–
200 mg L1 for 30 min as an effective, easily
available and low-cost disinfectant for routine use
to improve yellow perch hatchability |
