Effects of Mannan Oligosaccharide and Serotonin on Molting, Growth, Body Composition and Hepatopancreas Histology of White Leg Shrimp Litopenaeus vannamei (Boone 1931)

The effects of dietary mannan oligosaccharide (MOS), serotonin (5-HT) and the combination of both on molting, growth, survival, body composition, and hepatopancreas histology of the Pacific white shrimp Litopenaeus vannamei were investigated for 75 days. Dietary inclusion level of MOS at 3 g kg-1, serotonin at 20 mg kg-1, and both were tested in triplicate groups against a control diet lacking MOS or serotonin. The shrimps having an average initial weight of 1.35 +/- 0.04 g attained to final weights an average of 10.71 control, 11.05 serotonin and 12.26 MOS respectively. Although survival rate was high (86%) in the shrimp fed MOS-supplemented diet, no statistical difference was found among the groups (P>0.05). The results indicate that inclusion of 3 g kg-1 MOS into diet enhance shrimp survival, moulting rate, growth and FCR compared to the control. Serotonin inclusion at 20 mg/kg also improved the same parameters, but suppressed moulting rate in comparison to the other groups (P<0.05). Hepatopancreatic tissues were not affected by dietary treatments. Body composition (protein, lipid, ash and dry matter) of the shrimps were also similar in all the dietary groups. In conclusion, the current results have demonstrated that MOS at 3.0 g kg-1 inclusion level could be used as growth promoter in L. vannamei diets.