the efficacy of echinacea (echinacea purpurea) methanol extract on growth performance in grey mullet (mugil cephalus)

this experiment was conducted to evaluate the efficacy of different levels of echinacea (echinacea purpurea) methanol extract on the growth performances (final weight (fw), daily growth ratio (dgr), feed conversion rate (fcr), voluntary feed intake (vfi) and protein efficiency ratio (per) and some of hematological parameters (hemoglobin (hb), hematocrit (hct), red blood cell (rbc) and white blood cell (wbc) of  grey mullet (mugil cephalus). the experiment was conducted in a completely randomized design with 360 of larvae (with average weight of 0.75±0.03g) in 4 treatments: control group without using echinacea extract, an another groups (treatment 2, 3 and 4) the amounts of this  extract were 50,100 and 200 g/kg food. the highest fw (4.22±0.11g), dgi (1.72±0.50%) and the lowest fcr (0.95±0.05) and vfi (1.77±0.05%), were observed in treatment 4. but treatment 4 in all of these growth parameters did not show a significant difference compared with treatment 3 (p> 0.05). after 60 days, treatments 3 and 4, showed significantly higher rbc, wbc, hb and hct than those fed the control diet. finally, the present results suggest that diet containing 100 and 200 g kg-1 extract could improve growth and hematological parameter of m. cephalus.