Shrimp Broodstock Management
Shrimp broodstock management is essential for continuous operation for seed production. The maturation of the species differs greatly depending on the location and climatic conditions. Under pond conditions, maturity of shrimps generally occur after attaining a maximum size of 60-75 mm. Berried females are recorded year-round in some of the ponds. The ratio of berried females in total population is found to be higher during rainy months and during this period they carry good quantity of eggs (10000-80,000). Shrimps breed 3-4 times in a season. Successful community breeding and year-round seed production of shrimps under captive conditions is possible.
Since the juvenile seed requirement for commercial farming is not met from the natural resources, large-scale seed production under controlled conditions for year-round supply is extremely important. The technologies of large-scale seed production and grow-out culture have led to increased attention of the farmers and entrepreneurs for diversification of their culture practice.
Incubation period of eggs lasts between 10-15 days depending upon the optimum water temperature of 28-30°C. However, at lower temperature, the incubation period is longer. Different larval rearing technologies such as static, flow-through, clear or green water, closed or semi-closed, with or without circulation systems of larval rearing of shrimps under hatchery conditions have been developed. The green water technique generally provides higher sucess over other techniques.Bio-filter systems equipped with air-lift re-circulation has shown promising results in maintaining favorable water quality in different rearing media with enhanced rate of post-larval production.