Mahmoud Nafisi Bahabadi; Vahid Morshedi
Volume 4, Issue 1 , September 2015, , Pages 67-78
Abstract
At the present work, effects of salinity were studied on growth and feeding performance, survival rate and blood biochemical parameters of pre on-growing rainbow trout (Oncorhynchus mykiss) with initial weight 93.22±4.11 g for 60 days. After adaptation to water salinity for 10 days, 450 fish were ...
Read More
At the present work, effects of salinity were studied on growth and feeding performance, survival rate and blood biochemical parameters of pre on-growing rainbow trout (Oncorhynchus mykiss) with initial weight 93.22±4.11 g for 60 days. After adaptation to water salinity for 10 days, 450 fish were distributed in 5 treatments and 3 replicates according to a complete randomized design. Before adaptation to water salinity 1, 10, 25 and 50 days after introduction to a different salinity with in (10, 20, 30 and 40 ppt), growth and feeding parameters and some blood biochemical parameters were investigated. According to the obtained results of study, increase salinity up to 20 ppt, growth and feeding parameters significantly decreased including daily growth rate, specific growth rate, feed conversion efficiency between salinity groups and control group (P<0/05) and higher salinities (30 and 40 ppt), caused gregarious mortality. During the experiment, blood biochemistry parameters including osmolality, chlorine, sugar, cortisol, tri-iodo thyronin(T3), and Tetra–iodo–thyronin (T4) significantly increased with increasing water salinity (P<0/05). Overall, the obtained results indicated that rainbow trout with initial weighing 90 g, could be cultured successfully in water with salinity up to 20 ppt, although fish growth rate is lower than that in the fresh water.
