Entirely controlled reproduction of grass carp

In this study, it was aimed to determine the eggs number, rates of fertilized and infertilized eggsand the effects of three different concentrations (2, 3 and 4 ml/L) of alkali protease (Alcalase-Bacilluslicheniformis) on incubation duration, hatched eggs rate, living larvae rate and the duration of egg sacabsorption of larvae on eggs obtained entirely controlled method from grass carp. For this purpose, carppitiutary was injected to both male and female and their sperm and eggs were obtained. Total 12 zuggerjars with 7 liter capacity each were used for incubation of fertilized eggs. Incubation water hadtemperature 23ºC, pH 7.8 and dissolved oxygen 8 mg/L.Absolute egg numbers were determined as 844 for 1 kg fish weight. Fertilization rate was foundaverage 80.4%. Hatching rates in the eggs kept in 2, 3 and 4 ml/L alkali protease during incubation were94.2%, 95.3% and 95.4% respectively. It was 94% for control group. In addition, living rates were 80.8%,80.8% and 79.2% respectively. It was 78.8% for control group.There was not statistically significant differences among fertilization rates (p>0.05). But, thedifferences among hatching rates and among living larvae rates were statistically found significant(p<0.05) as a result of treatment with different alkali protease concentrations of eggs during incubationperiod.In conclusion, in terms of fertilized, eggs hatched eggs and a live larvae number of 16880 eggsused, 3ml/L concentration of alkali protease has better effect on grass carp eggs compared with otherconcentrations.Key Words: Grass carp, Ctenopharyngodon idella, reproduction, fertilization, spawning, alkaliprotease.I