Acipenser persicus is the most important sturgeon species in the south Caspian Sea region, showing high mortality during larval culture. The a im of this study was to use the freshwater rotifer, Brachionus calyciflorus to feed A. persicus larvae to improve survival rate s and enhance resistance in these larvae at the onset of exogenou s feeding. Three experimental groups were used in this study; Control group similar to the f eeding protocol of the hatchery was initially fed decapsulated cysts of Artemia and then fed daphnia, group 1 was fed a mixed diet of decapsulated Artemia cysts, daphnia and freshwater rotifers, group 2 was fed only on freshwater rotifers, and group 3 was fed freshwater rotifers e nriched with vitamin C (ascorbic acid 6-palmitate). A total of 45 larvae were stocked in ea ch experimental tank (100 l capacity) filled with 30 l of water. Three replicates were used for each experimental group. Larvae were fed four times a day at the rate of 30% of body weight per day for 8 days. Mean dissolved oxygen, pH and water temperature thr oughout the experimental period were 9.58±0.2 mg/l, 8.5±0.1 and 22.5±0.5 ºC, respectivel y. DNA sequence of genome DNA extracted from the native freshwater rotifer under study was determined and registered. Results showed significant differences in specific growth rate (SG R), percentage weight gain (WG), feed conversion ratio (FCR), and condition factor (cf) o f experiment group 1 and group 3. Survival rates of the experiment groups 2and 3 were signific antly different from those of the experiment control group and 1. twenty first feeding day of the study showed ration oral size to body length was evaluated by (0 /1 ± 0/01) mm. This study demon strated that Brachionus calyciflorus is a suitable live food for larval feeding and can be cu ltured, enriched and used along with other freshwater rotifers.
کلید واژگان :rachionus calyciflorus, Acipenser persicus, fatty acid, vitamin C, survival rate,
ارزش ریالی : 300000 ریال
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