Influence of different levels of dietary nucleotides on growth performance, survival and carcass composition of sterlet (Acipenser ruthenus)

The use of dietary nucleotides in mammals and aquatic organisms has shown various positive effects on growth, immune system, gastrointestinal tract, and intestinal flora, improvement of reproduction, fat metabolism and increased resistance to diseases. The aim of this study was to determine the effect of dietary nucleotide (vanagen) on growth, survival and carcass composition in sterlet fish (Acipenser ruthenus). For this purpose, fish with an average weight of 95±1 g were divided into 5 treatments with 3 replications. The fish were then fed a diet containing 0, 0.15, 0.25, 0.35 and 0.5% nucleotide supplements for ten weeks. The results showed mean of final weight, weight gained (WG), specific growth rate (SGR), and protein efficiency ratio (PER) increased significantly with increasing nucleotide levels (P<0.05), and in the treatment containing 0.5% of nucleotides were the highest. (FCR) was the lowest in the treatment containing 0.5% (P<0.05). According to the results, the amount of protein and carcass fat in 0.25% was the highest and the lowest was observed in the control treatment (P<0.05). The results showed addition of dietary nucleotides to the diet of sterlet fish improved growth indices such as body weight gain, specific growth rate, and protein efficiency rate, feed intake and reduced feed conversion ratio. According to the results, concentrations between 0.25-0.5percent of vanagen nucleotides are recommended to achieve optimal growth and carcass composition in sterlet.