The aquatic fern Azolla (Azolla caroliniana) can be easily grown organically in North Eastern India due to favorable climatic conditions. This fern was fed to the grass carp, Ctenopharyngodon idella (Val.) as a step towards producing organic fish. In the study, Azolla was found to be a preferred feed by the grass carp and mean daily growth increment was recorded. The statistically paired t-test indicated that the final weight gain of grass carp in Azolla fed ponds were significantly higher (tcal=4.85***; df=13) than that of the control pond. The net profit for production of organic grass carp was calculated as 0.12 $/m2. It was concluded that the utilization of organic Azolla through grass carp is one of the best options for production of fish biomass from the aquatic habitat. This would also pave way for producing organic fish and help in bridging the gap between production and demand of organic fish in the country.
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Alderman, D. and Hastings, T. 1998. Antibiotic use in aquaculture: development of antibiotic resistance potential for consumer health risks. International J. of Food Science and Technology, 33: 139-155.
APHA. 1998. Standard Methods for the Examination of Water and Wastewater, (20th Ed.), APHA, AWWA and WPCF, Washington, DC.
Azad, I.S. 1996. Growth performance of grass carp fingerlings fed on Ageratum conyzoides, a common terrestrial weed of Manipur. J. of Inland Fisheries Society of India, 28(1): 44-49.
Bernward, G. and Thomas, C. 2002. International Federation of Organic Agriculture Movement, IFOAM Annual Report, 1-28.
Bujarbaruah, K.M., Das, A. and Nanda, S.K. 1996. Status of animal husbandry in Meghalaya. ICAR Research Complex for NEH Region publication, 12: 27-29.
Bujarbaruah, K.M. 2004. Organic Farming: Opportunities and Challenges in North Eastern Region of India. International Conference on Organic Food. 13-23.
Bjorklund, H., Bondestam, J. and Byland, G. 1990. Residue of oxytetracycline in wild fish and sediments from fish farm. Aquaculture, 86: 359-367.
Devaraj, K.V., Manissery, J.K. and Keshavappa, G.Y. 1986. On the growth of grass carp (Ctenopharyngodon idella) fed with Luceme (Medicage sativa) and Hydrilla (Hydrilla verticillata) ad libitium in cement cisterns. Mysore J. of Agricult. Science, 19: 275-278.
Grygierek, K. 1973. The influence of phytophagous fish on pond zooplankton. Aquaculture, 2: 197-208.
Majhi, S.K. 2005. Prospect of integrated fish-livestock aquaculture in North Eastern Hill Region of India. Ecology Env. & Conservation, 11(2): 287-291.
Prasad, R. 1998. A practical manual for soil fertility, P.50. Division of Agronomy, Indian Agricultural Research Institute. ICAR Agronomy National Professor Unit, New Delhi. 50 pp.
Sivakumar, C. and Solaimalai, A. 2003. Weed management in rice-fish-azolla farming system-A Review. Agricultural Review, 24(3): 190-196.
Sardana, V. 1997. Agronomic evaluation of biofertilizers to supplement inorganic fertilizers for sustained crop production-A Review. Agricultural Review, 18(2): 69-93.
Suresh, V.R. and Mandal, B.K. 2002. Growth and feed utilization of grass carp fingerlings. Indian J. of Fisheries, 49(2): 155-160.
Venkatesh, B. and Shetty, H.P.C. 1978. Nutritive value of two aquatic weeds and a terrestrial grass as feed for grass carp Ctenopharyngodon idella (Val.). Mysore Journal of Agricultural Science, 12: 605-607.
Vinod, K., Mahapatra, B.K., Majhi, S.K. and Mandai, B.K. 2004. Potentials of terrestrial weeds for the production of grass carp Ctenopharyngodon idella (val.) in Meghalaya, North Eastern India, SAARC Journal of Agriculture, 2: 211-219.