A review on research achievements of rainbow trout (Oncorhynchus mykiss) aquaculturein inland brackish water in central area of Iran

Document Type : Other

Author

Bafgh Saltwater Fisheries Research Center, Fisheries Research Institute of Iran

Abstract

Inland brackish aquaculture may offer an opportunity for income diversification and a potentially productive use of land that can no longer support traditional agriculture in salt-affected parts of inland production and investment levels are characteristically low. It may also provide a means of defraying all or part of the cost of surface and subsurface water management systems. It seems inland brackish aquaculture will be an essential component of salinity management in the future, because unlike many other adaptation strategies, it can be effectively integrated with engineering solutions to treat salinised land. This activity needs to develop in a manner that both prevents the further degradation of agricultural land and provides opportunities for an alternative and sustained economic base for dependent rural communities. Most central areas of Iran are rich in saline water resources with different salinities (5-40g/l). Applying these resources for aquaculture production is a potential adaptive use, although it maybe limited by some factors especially strict environmental conditions. The limitations, have led to the logical progression of investigating the suitability of these resources for aquaculture. So, regarding to well adaptation of rainbow trout to rapid changes in salinity and profitability of its production in state of Iran, this species promoted as potential candidate for aquaculture in these regions. After feasibility studies, supplementary researches carried out during recent decade in Inland Saline Water Aquaculture Research Center, Bafgh, Iran. According to the results, rainbow trout well adapted to underground brackish well water (in salinity 14g/l) without any mortality and growth performance was desired. It was also introduced the earth pond as culturing system for rainbow trout through semi-intensive method during cold seasons when the cool weather provide a suitable conditions in cultivating ponds. Investigations on increasing production methods in selected system indicated that reusing wastewater and establishing net pen in pond are the effective ways than aeration by submerged and surface aerators. Study on protein and energy requirements of rainbow trout in this medium showed the best growth was obtained by fishes fed by 35% protein and 4750kcal/kg digestible energy levels. Considering some gonadic and somatic indices of rainbow trout in the research station demonstrated that body growth and gonad development were faster than fresh water, as well as maturation speed was quicker too. Findings of this paper demonstrated that by using appropriate semi-annual production system, rainbow trout farming in brackish water is a profitable method to develop inland aquaculture industry in Iran

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