Effects of replacing different levels of fermented soybean meal in diet on some hematological and immunological indices of Beluga (Huso huso)

This study was conducted to evaluate the effects of replacing fishmeal with fermented soybean meal on some hematological and immunological indices of Beluga, Huso huso. For this purpose, 240 Beluga (394.6 ± 4.3 g) were distributed in eight treatments (with three replications). The experimental treatments included T1: fish meal (FM), T2: (FM + methionine and lysine), T3: Fermented soybean 40% (FSBM40), T4: (FSBM60), T5: (FSBM80), T6: (FSBM40 + methionine and lysine), T7: (FSBM60 + methionine and lysine) and T8: (FSBM80 + methionine and lysine). During the 56-day feeding period, the fish were fed to apparent satiation three times daily. The results showed that there was no significant difference in hemoglobin, hematocrit, MCHC, neutrophil, monocyte and eosinophil values (p>0.05). However, the highest number of white and red blood cells was observed in the diets containing FM and FM + methionine and lysine, respectively (p<0.05). Furthermore, higher amounts of MCV and lymphocytes in T6 and higher amounts of MCH in T5, T6 and T8 were observed than in the other treatments (p<0.05). Also, the highest amounts of lysozyme were observed in T4. In addition, T4 and T7 exhibited higher amounts of IgM and total immunoglobulin than the other treatments (p<0.05). Based on the results, the best performance of hematological and immunological indices was observed in replacing 40-60% fishmeal with fermented soybean meal.