The effect of dietary lysine and methionine amino acids on growth indices, blood parameters, liver enzymes and immune responses in beluga, Huso huso (L. 1758)

The present study was conducted to examine the effect of dietary lysine and methionine amino acids on growth, blood parameters, liver enzymes and immune responses of beluga, Huso huso. Four experimental soy protein-based treatments including D0 (without lysine or methionine), D1 (lysine), D2 (methionine) and D3 (lysine + methionine) were formulated in triplicate groups. A total number of 240 juvenile beluga with average weight of 144.6 ± 4.64 g were fed with the experimental diets in the same rearing conditions for 12 weeks. L-lysine and DL-methionine were added to the diets containing 344 g/kg soybean meal at 22.02 and 12.94 g/kg dry diets, respectively. Growh indices in D3 (lysine + methionine) were significantly (p<0.05) higher than those in other treatments. The lowest content of HSI belonged to D0 (control) which exhibited significant difference (p<0.05) compated to the other treatments. The values of hematocrit, hemoglobin, glucose, total protein, liver enzymes and number of red blood cells in in D3 revealed significant enhancement compared to D0 (p<0.05). There was an increased immune parameter including total Ig and lysozyme in treatments with supplemented amino acids (D1, D2 and D3) compared to D0 (control) with significant difference in case of D3 (p<0.05). In conclusion, beluga juveniles effectively utilize the supplemented lysine at 22.02 g/kgand methionine at 12.94 g/kgin the dry diets containing 344 g/kg soybean meal to enhance growth performance, haematological and immune parameters.