The effects of different levels of dietary prebiotic on growth performance and some non-specific immune parameters in zebra fish (Danio rerio)

The aim of the present study was to evaluate the effects of different levels of prebiotic on growth performance and non-specific immune parameters of zebra fish. Four hundred and twenty fish (mean weight 45 ± 0.1 mg) were supplied, randomly stocked in aquaria assigned to four treatments repeated in triplicates and fed with experimental diets contain 0, 0.5, 1 and 2% prebiotic for 8 weeks. At the end of feeding trial, growth performance and feed utilization parameters (final weight, specific growth rate and feed conversion ratio) as well as non-specific immune parameters (total immunoglobulin, total protein and alkaline phosphatase activity) were measured. The results revealed that dietary administration of prebiotic had no significant effect on growth performance (P>0.05). Also, the study of non-specific immune parameters revealed that inclusion of 0.5 and 2% prebiotic in diet remarkably increased total Ig (P<0.05). Feeding on 2% prebiotic significantly increased ALP activity (P<0.05). Regardless of inclusion level, prebiotic administration in zebrafish diet elevated total protein levels (P<0.05). According to these results it seems that inclusion of higher prebiotic levels (2%) increase non-specific immune parameters in zebra fish.