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The effects of dietary nucleotide (0.2%) on the growth, intestinal morphology as well as fatty acid profile of the whiteleg shrimp, Litopenaeus vannamei was investigated in Bushehr province (Delvar) for a 5-week feeding trial. The experiment was carried out in triplicate in circular PVC tanks of 300L capacity. Each tank was randomly filled with 25 shrimps weighting on average 3.21±0.03g. Added dietary nucleotide significantly improved growth factors such as 10% weight increase, 7.97% increase in specific growth rate (SGR), 11.32% increase in protein efficiency ratio (PER), 9.64% decrease in feed conversion ratio (FCR) and 14:1n5, 20:3n3 and DHA fatty acids. However, no significant differences were evident in survival, carapace length gain, daily feed consumption and saturate fatty acid (SFA), monounsaturated fatty acid (MUFA), poly unsaturated fatty acid (PUFA) content, n-3/n-6 as well as EPA+DHA fatty acids between the two treatments. Intestine epithelium cells height (IECH) in the abdominal first section were significantly higher in shrimp fed by dietary nucleotide. *Corresponding