Effects of dietary administration of purple coneflower on growth, hematology and non-specific immune parameters in juvenile sterlet (Acipenser ruthenus)

This study was conducted to evaluate the effects of purple coneflower (Echinacea purpurea) (EP) on growth and blood parameters in juvenile sterlet (Acipenser ruthenus). One hundred and eighty fish (mean weight 75±1SDg) divided into 12 tanks (n=15) after adaptation period. Base diet was supplemented with 0 (control), 0.5, 1 and 2g/Kg EP to formulate experimental diets. Fish were fed daily at a rate of 3% of body weight. After 60 days, all fish were weighted for growth analysis and blood samples were collected to assess hematological parameters. Results showed that growth indices were not significantly affected by EP extract (p 0.05). There was no notable differences in hematological parameters, including red blood cell, white blood cells, hemoglobin, lymphocyte and neutrophil percentage in treatments compared to the control group (p 0.05). Total protein, albumin, globulin and albumin to globulin ratio did not reveal any differences between experimental and control groups (p 0.05). Lysozyme and Immunoglobulin M in fish fed with EP were higher, compared to the control group (p 0.05). It could be concluded that diet supplementation with EP improved immune system function in A. ruthenus, but had no effect on growth in this species.