ABSTRACT
The aim of the current study was to evaluate the dietary supplementations of a yeast nucleotide (NT) in doses of 0.0, 0.5, 1.5 and 2.5 g NT/kg diet on growth, hemato-biochemical parameters and expressions of some growth-related genes in Nile tilapia, Oreochromis niloticus. After 60 days, highest growth performance, feed utilization, and protein efficiency ratio were recorded in fish fed 2.5 g NT/kg diet. The haemato-biochemical parameters showed the highest significant values in NT-fed fish compared with the control one. Significant increases in values of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), Alkaline Phosphatase (ALP), urea, and creatinine were observed in fish supplemented with 2.5 g NT/kg diet. Stimulatory effects on lipase, amylase, and growth hormone were observed in higher NT-supplemented fish groups. The highest whole body protein and fat contents were recorded in fish fed 0.5 and 2.5 g NT/kg diet, respectively. Ghrelin and insulin-like growth factor gene expressions showed significant up-regulation in the fish supplemented with 1.5 and 2.5 g NT/kg diet, successively. The results recommended the administration of dietary NT at percentages of 1.5– 2.5 g NT/kg diet had beneficial effects on Nile tilapia.
Disclosure statement
No potential conflict of interest was reported by the authors.