Effect of feeding Artemia Urmiana cysts on performance and survival of Caspian brown trout (Salmo trutta caspius) fish at the larva stage

This study was conducted to evaluate the effect of feeding different levels of Artemia Urmiana cysts on performance and survival of Caspian brown trout fish. The treatments included different levels (25, 50, 75 and 100 %) of Artemia Urmiana cysts to Caspian brown trout fish with an average weight of 120 ± 25 g in active phase of larva stage until the weight of one gram. Feed intake (FI), weight gain (WG), body weight (BW), feed conversion ratio (FCR), specific growth rate (SGR) of the treatments were determine and the survival percentage index was calculated based on the number of remaining larvae in the sites on the total number of larvae. The result of study showed that the higher feed intake was for 25 and the lower feed intake was for 50% of Artemia urmiana cysts treatments. Also the best specific growth rate and feed conversation ratio was related to the 25 % of Artemia Urmiana cysts groups (P≤0.05). Additionally the best survival index was for fish that fed by 75% and the worst survival index was for fish that fed by 100% of Artemia urmiana cysts. In conclusion we could demonstrated that feeding Artemia Urmiana cysts may have some beneficial effects on the performance and survival of Caspian brown trout (Salmo trutta caspius) fish at the larva stage.

A survey of the functional, gut digestive, and serum antioxidant factors in Salmo trutta caspius (Kessler) fingerlings with the application of a dietary synbiotic

This study evaluated the effectiveness of BetaPlus® combined with isomalto-oligosaccharide (IMO) in Caspian brown trout, Salmo trutta caspius (Kessler), fingerlings. A total of 120 Caspian brown trout (8.75 ± 0.03 g) were fed in two treatments, including the control diet and the synbiotic diet (0.1% BetaPlus® + 0.2% IMO) in three replicates per treatment for seven weeks. The growth indices (final weight, weight gain, average daily growth, specific growth rate, feed efficiency, and protein efficiency ratio) exhibited significant improvement in the fish fed the synbiotic diet (P < 0.05). The highest ash crude protein, and crude fiber, as well as the lowest crude lipid, dry matter, and carbohydrate detected in the carcass of fish treated with the synbiotic were significant (P < 0.05). In addition, the fish fed the synbiotic diet showed significantly higher gut trypsin activity and trypsin:chymotrypsin ratio, as well as serum superoxide dismutase activity (P < 0.05). Thus, BetaPlus® in combination with IMO can effectively lead to a considerable increase in functional factors, as well as gut proteases and serum antioxidant indicators in S. trutta caspius fingerlings.