The effect of glutamine on growth, blood and immunity parameters in Siberian sturgeon (Acipenser baerii, Brandt 1869)

Siberian sturgeon is a suitable species for using in aquaculture industry. The purpose of this study was to investigate the effect of glutamine on growth and blood and immunity indices of Siberian sturgeon fingerling and to determine the optimal amount of glutamine in rearing conditions. This study was performed on 126 fish with a mean weight of 45.71±7.56g in six treatments (control, 5, 10, 15, 20 and 30g glutamine/kg diet) and three replicates during 8 weeks. The results showed that there was no significant difference in growth factors (P>0.05). However, final weight, final length, the percentage of increasing body weight, feed conversion ratio, specific growth factor and daily growth rate were higher in fish fed the diet containing 30g glutamine/kg diet compared to other treatments. The highest obesity coefficient was observed in fish fed the diet containing 5g glutamine/kg diet. Also, there was no significant difference in red and white blood cell count, hemoglobin, hematocrit, MCV, MCH, MCHC, neutrophil and lysozyme (P>0.05), but lymphocytes, monocytes, eosinophils, IgM and total immunoglobulin were significantly different (P<0.05). Glutamine had no significant effect on most of the blood parameters of Siberian sturgeon, but an increase in immunity parameters such as lymphocytes, monocytes, total immunoglobulin and IgM was observed. It seems that the addition of glutamine to the basal diet is not necessary in this age and culture conditions and the basal diet supports the needs of fish.