The effect of Fermacto prebiotic on growth performance, some intestinal morphology and microbial floor in the rainbow trout (Oncorhynchusmykiss)

Prebiotics are not digestible ingredients food that stimulates the growth and activity of bacteria in the intestines through beneficial effects on the health of the host. In addition, this report is shown a positive effect of adding these additives diet on growth performance. The present study was carried out to investigate an intestinal microbial balance, growth performance, and immune responses of fish trough addition of Fermacto prebiotic to diet of rainbow trout, Oncorhynchusmykis. One-hundred and sixty two (162) rainbow trout with mean live weight 19.06±1.83 g were randomly selected and allocated to 9 tanks (18 fish per tank). Three levels of Fermacto (0, 1 and 2 g/kg diet) were used. Each treatment was replicated 3 times. The experiment was carried out for 10 weeks. Fermacto supplement showed a significantly increasing effect on the feed conversion ratio and decreased specific growth rate and weight gain at the end of experiment. Fermacto caused significant differences in bacterial population fish intestinal microbial balance lowest length was observed in fish receiving the diet supplemented with 2 g/kg Fermacto, whereas application of Fermacto at the applied levels showed no effects on growth and health of experimental fish.