Brood stock management | ||||||
---|---|---|---|---|---|---|
Item | Tilapia Oreochromis niloticus | Grasscarp Ctenopharyngodon idella | Bighead carp Artistichthys nobilis | Silver carp Hypopthalmichthys molitrix | Puntius Puntius gonionotus | Freshwater prawn Macrobrachium rosenbergii |
Number of brooders (Male / Female) | M=300 | M=40 | M=25 | M=60 | M=100 | 4,000 |
F=600 | F=90 | F=20 | F=30 | F=50 | ||
Keeping place (pond/tank) | 8 ponds | 5 ponds | 4 ponds | 5 ponds | 2 ponds | 4 ponds |
24 tanks | 3 tanks | |||||
Kept separate or mixed (age or sex) | separate, 1–2 yr. | separate sex basis | separate sex basis | separate sex basis | mixed | mixed, 6 months |
Kept until age of | 3 yrs. | 8 yrs. | 8 yrs. | 6 yrs | 5 yrs | 2 yrs |
Spawning (one pond or tank) | ||||||
Method (natural/stripping) | natural | induced spawning by hormone injection | induced spawning by hormone injection | induced spawning by hormone injection | natural | natural |
Season | year round | Sept – March | Sept - March | Sept - March | Sept - March | year round |
Place (pond/tank) | pond / tank | tank | tank | tank | pond | pond / tank |
Stocking density | 15 fish / tank | 12 fish / tank | 12 fish / tank | 15 fish / tank | 21 fish / tank | - |
Female / male ration in one pond/tank | pond: 40 F - 20 M | 4 F - 8 M | 4 F - 8 M | 5 F - 10 M | 1 F - 2 M | - |
tank: 10 F - 5 M | ||||||
Water temp. C° | 25 – 30°C | 24 – 28°C | 24 – 28°C | 24 – 28°C | 25 – 30°C | 25 – 30°C |
Duration in pond / tank: | pond: 4 – 6 wks | 24 hrs | 24 hrs | 24 hrs | 24 hrs | - |
tank: 3 wks | ||||||
Time for hatching | 2 – 3 wks (incl. spawning) | 17 – 20 hrs | 17 – 20 hrs | 17 – 20 hrs | 1 month | 1 wk |
Number of eggs produced | 200 – 300 / female (estimate) | 300 – 600 thousand / female | 250 – 500 thousand / female | 250 – 500 thousand / female | 300 – 500 / female | 5000 – 10000 / female |
Number of larvae / fry collected from pond/tank | pond: 8000 / cycle | 500,000 | 300,000 | 200,000 | 30,000 | - |
tank: 2000/cycle | ||||||
Number of ponds / tanks used in one turn | 4 ponds | 8 ponds | 3 ponds | 3 ponds | 2 ponds | 3 – 10 tanks |
12 tanks | ||||||
Size of pond / tank used | pond:400 – 600 m2 | 400 – 600 m2 | 400 – 600 m2 | 400 – 600 m2 | 800 m2 | tank 500 l |
tank: 10 – 25 m2 | ||||||
Fry rearing (one pond or tank) | ||||||
Place (pond or tank) | tank | pond | pond | pond | pond | |
Age of larvae / fry stocked | 2 – 3 wks | 2 months | 2 months | 2 months | 3 months | PLs |
Stocking density | 2000 / tank | 150 – 160 / m2 | 250 / m2 | 150 – 160 / m2 | 20 / m2 | - |
Number of larvae / fry stocked | 2000 / tank | 62,500 | 100,000 | 66 – 67,000 | ||
Duration of rearing | 2 – 3 wks | 3 months | 3 months | 3 months | 3 months | - |
Water temp. C° | 25 – 30°C | 25 – 30°C | 25 – 30°C | 25 – 30°C | 25 – 30°C | 25 – 30°C |
Average weight of fry harvested | 3 g | 200 g | 200 g | 200 g | - | |
Survival rate | 98 – 100 % | 70 % | 70 % | 70 % | 100 % | |
Fries transferred to: | supplied to farmers | stocking to river | farmers + river | farmers + river | stocking to river | - |