Study efficacy of Clupeonella spp. on some growth characteristics farmed Beluga (Huso huso Linnaeus 1758)

Since Clupeonella spp. are as a main food for huso huso in the natural ecosystem of the Caspian Sea, in this study the growth characteristics of farmed Huso huso fed by crude Clupeonella spp was investigeted. For this purpose, 120 fish with a mean initial weight of 1175±238 gr (±SD) were stocked in fiberglass tanks. Fishes were fed with five levels of crude kilka comprising 0, 25, 50, 75 and 100% in diet artificial diet for 60 days. This trial was carried out in completely randomized design with at least three replicates for each treatment. Finally, the highest growth performance based on final length, weight and average biomass, condition factor (CF), specific growth rate (SGR), average daily growth (ADG), body weight% (BW%) and average production were obtained in the treatment 5 (100% artificial diet without kilka). However, there was no significant difference in the growth performance of fish fed with diet 5 (1.07±0.04) and 4 (0.81±0.02) (p>0.05) except feed conversion ratio (FCR) (p<0.05). In addition, diet economic estimates for the treatment 4 (25% kilka+75% artificial diet) was 10% lower than the treatment 5 (100% artificial diet without kilka). The results of this study showed adding 25% kilka in diet of farmed Huso huso affects on its growth characteristics. Therefore, the use of 25% kilka in the daily diet of the farmed Huso huso is recommended due to kilka relative abundant and availability as well as its high nutritional value and appropriate price.