World Aquaculture - December 2014

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54 DECEMBER 2014 • WORLD AQUACULTURE •
during the 3-4 weeks of rearing indoors (Fig. 3).
Fry rearing. Fry are further reared in cement tanks to
fingerlings. Tanks may be prepared with a soil base and manured
as in carp ponds to obtain a plankton bloom. Rearing tanks are
filled with a minimum of 30 cm of water for easy visibility of
fish activity. Fry show shoaling behavior and are active during
feeding. Hence, a low density of 100-150/m2 is maintained to
minimize competition and obtain homogenous growth and
better survival (Sahoo et al. 2014). Fry are fed with crumbled
feed containing 30 percent crude protein ad libitum, as visually
indicated by satiation of fish. Filamentous algae grows in tanks
because of the low water level and must be removed to avoid
oxygen depletion and retarding swimming activity of fry. Survival
is >60 percent and weight gain is > 500 mg and ≥ 60 percent
during the 6-7 weeks of rearing. Fingerlings can be sold directly
as ornamental fish at this stage or can be further reared in nursery
tanks before grow-out (Fig. 4).
Best Management Practices
• Broodfish of > 100 g is necessary to induce spawning.
• Broodfish can be reared by stocking at 1-2/m2 and feeding
a 30-32 percent protein pelleted diet. Intermittent water exchange
in broodfish pond enhances maturity for a better output of healthy
eggs.
• Injection of 1-1.5 mL Ovaprim/kg of female and stripping
after 12-13 h of injection is sufficient to obtain good breeding
performance and egg quality.
• Larvae can be reared at a density of 500-1000/m 2 for good
growth within a short time, thereby enhancing survival.
• Live feed should be provided during an initial rearing
phase and larvae should be gradually weaned to the compound
larval feed after 10-11 days of fertilization. This acclimation to
feed stimulates fry to accept feed immediately after release into
nursery tanks, which ultimately increases survival.
Notes
S.K. Sahoo, S. Ferosekhan, M. Paramanik, S. K. Swain, Central
Institute of Freshwater Aquaculture, Kausalyaganga, Bhubaneswar
751 002, Orissa, India
Corresponding author email:
References
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the world: Horabagrus brachysoma (Gunther, 1864) (Bagridae).
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Bhat, A. 2001. New report of the species, Horabagrus brachysoma in
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Kurian, M and N.D. Inasu. 2003. Reproductive biology of a catfish
Horabagrus brachysoma (Gunther) from inland waters of Kerala.
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Sahoo, S.K., S.S. Giri, M. Paramanik and S. Ferosekhan. 2014.
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FIGURE 4. Fingerlings produced in nursery tanks before grow-out. FIGURE 3. Fry produced in high-density rearing during a 3-4 wk indoor rearing
period.