Aquaculture of cobia
Their rapid growth rate in aquaculture, as well as the high quality of their flesh, makes cobia potentially one of the more important potential marine fish for aquaculture production.
Greater depths, stronger currents, and distance from shore all act to reduce the environmental impacts often associated with fin fish aquaculture. Offshore cage systems could become some of the most environmentally
Production
Wild cobia
Broodstock are reared in controlled ponds or tanks. These tanks are often stocked with cleaner fish, Gobiosoma oceanops, as a biological control for any remaining ectoparasites. The broodstock diet includes sardines, squid and formulated feeds, as well as vitamin and mineral supplements. The water temperature is used to control spawning.[5][7]
The
Optimal rearing densities are required when rearing larvae. Even though water quality and food can be controlled, it has been shown that high rearing densities may still affect growth and survival of the larvae through responses related to crowding.[10] In addition, juveniles exposed to varying salinities exhibited sustained growth and improved health at higher salinities, 15 and 30 ppt.[11]
Cobia larvae
Juveniles thrive on a wide range of protein and lipid, but there are optimal levels where they get the most benefit. After an 8-week growth trial, juvenile cobia displayed a peak in their weight gain with a dietary protein concentration of 44.5%.
The cobia are then transferred to open ocean cages for final the grow-out when they reach 6–10 kilograms (13–22 lb).
Diseases
- Nephrocalcinosis (kidney stones) cause significant mortality during both the hatchery and grow-out stages. These stones vary in diameter from 2–6 millimetres (0.079–0.236 in) in the kidney and can block the urethra. This condition is not fully understood, but is thought to be a symptom of prolonged exposure to free carbon dioxide in excess of 10 mg/L. The ratio of calcium to magnesium in the diet could also be out of balance.[17]
- A Sphaerospora-like myxosporean infection caused 90% mortality during one month in a marine cage cultured in Taiwan.[19]
Benefits and constraints
However, such operations require more developed infrastructure than near-shore aquaculture systems, which makes them expensive. Offshore sites have access difficulties and much higher labour costs.
See also
- List of harvested aquatic animals by weight
References
- ^ Kaiser, J.B. & Holt, G.J. 2004. Cobia: a new species for aquaculture in the US. World Aquaculture, 35: 12–14
- ^ a b c d e Liao, I.C., Huang, T.S., Tsai, W.S., Hsueh, C.M., Chang, S.L. & Leano, E.M. (2004) "Cobia culture in Taiwan: current status and problems" Aquaculture, 237: 155–65.
- ^ Nhu, V. C., Nguyen, H. Q., Le, T. L., Tran, M. T., Sorgeloos, P., Dierckens, K., Reinertsen H., Kjorsvik, E. & Svennevig, N. (2011) Cobia Rachycentron canadum aquaculture in Vietnam: recent developments and prospects Aquaculture 315: 20–25
- ^ Rachycentron canadum FAO Cultured Aquatic Species Information, Rome. Updated 23 May 2007.
- ^ a b c d e f g Benetti, D. D., Orhun, M. R., Zink, I., Cavalin, F. G., Sardenberg, B., Palmer, K., Dnlinger, B., Bacoat, D. & O’Hanlon, B. (2007) "Aquaculture of cobia (Rachycentron canadum) in the Americas and the Caribbean" Archived July 26, 2010, at the Wayback Machine RSMAS, p. 1–21
- ^ Benetti, D.D., Alarcon, J.F., Stevens, O.M., O'Hanlon, B., Rivera, J.A., Banner-Stevens, G. and Rotman, F.J. (2003) Advances in hatchery and growout technology of marine finfish candidate species for offshore aquaculture in the Caribbean Proceedings of the Gulf and Caribbean Fisheries Institute, 54: 475–487
- ^ .
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- ^ Faulk, C.K. & Holt, G.J. (2005) Advances in rearing cobia Rachycentron canadum larvae in recirculating aquaculture systems: live prey enrichment and greenwater culture Archived 2012-04-25 at the Wayback Machine Aquaculture, 249: 231–243
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- .
- ^ Faulk, C.K. & Holt, G.J. (2006) "Responses of cobia Rachycentron canadum larvae to abrupt or gradual changes in salinity" Archived 2012-04-25 at the Wayback Machine Aquaculture, 254: 275–283
- ^ a b Chou, R.L., Su, M.S. & Chen, H.Y. (2001) "Optimal dietary protein and lipid levels for juvenile cobia (Rachycentron canadum). Aquaculture" 193: 81–89
- ^ Wang, J.T., Liu, Y.J., Tian, L.X., Mai, K.S., Du, Z.Y., Wang, Y. & Yang, H.J. (2005) "Effect of dietary lipid level on growth performance, lipid deposition, hepatic lipogenesis in juvenile cobia (Rachycentron canadum)" Archived 2012-04-25 at the Wayback Machine Aquaculture, 249: 439–447
- ^ Chou, R.L., Her, B.Y., Su, M.S., Hwang, G., Wu, Y.H. & Chen, H.Y. (2004) "Substituting fish meal with soybean meal in diets of juvenile cobia Rachycentron canadum" Archived 2011-12-15 at the Wayback Machine Aquaculture, 229: 325–333
- ^ Craig, S.R., Schwarz, M.H. & McLean, E. (2006) "Juvenile cobia (Rachycentron canadum) can utilize a wide range of protein and lipid levels without impacts on production characteristics" Archived 2012-04-25 at the Wayback Machine Aquaculture, 261:384–39
- ^ a b c Benetti, D. D., O’Hanlon, B., Rivera, J. A., Welch, A. W., Maxey, C. & Orhun, M. R. (2010) "Growth rates of cobia (Rachycentron canadum) cultured in open ocean submerged cages in the Caribbean"[permanent dead link] Aquaculture 302: 195–201
- ^ Franks, J.S., Warren, J.R. & Buchanan, M.V. (1999) "Age and growth of cobia, Rachycentron canadum, from the northeastern Gulf of Mexico" Fishery Bulletin 97: 459–471
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- ^ Naylor, R. & Burke, M. (2005) "Aquaculture and ocean resources: raising tigers of the sea" Annu. Rev. Environ. Resour. 30: 185–218