Effects of lysophospholipid on utilizing different sources and levels of carbohydrate in rainbow trout (Oncorhynchus mykiss) diet

The aim of the present study was to investigate the effects of dietary lysophospholipid and carbohydrates (rye and corn meal) on growth performance, blood and biochemical parameters in rainbow trout. So, 480 fish (6.70 ± 0.99 g in weight) were fed with experimental diets containing 100 g/kg corn, 250 g/kg corn, 100 g/kg corn + 9 g/kg lysophospholipid, 250 g/kg corn + 9 g/kg lysophospholipid, 100 g/kg rye, 250 g/kg rye, 100 g/kg rye + 9 g/kg lysophospholipid and 250 g/kg rye + 9 g/kg lysophospholipid in triplicate. The experimental design was a 2 × 2 × 2 factorial arrangement. Results of growth performance demonstrated elevating in final weight, specific growth rate and feed intake in Tcorn100+lyso and Tray100+lyso, whereas Tcorn250+lyso and Tray250+lyso contrarily led to lower growth performance (p<0.05). Also, RBC and hematocrit indicated interaction effects between diet × lysophospholipid and lysophospholipid × carbohydrate level (p<0.05). RBC and hematocrit were elevated in Tcorn100+lyso and Tray100+lyso (p<0.05). Comparative results of biochemical parameters showed reaction effects of cholesterol between diet × lysophospholipid (p<0.05). Cholesterol values reduced by adding lysophospholipid to different levels of rye and corn and also higher value was observed in Tcorn100+lyso and Tray100+lyso compared to Tcorn250+lyso and Tray250+lyso (p<0.05). It seems that rainbow trout has potency of using 250 g rye and corn in diet containing fat powder without lysophospholipid, while lysophospholipid negatively affects this level of carbohydrates. However, lysophospholipid helps enhancing growth and erythropoiesis in the levels of 100 g rye and corn.