Effects of lipid enhancement on somatic growth, gonadal development and biochemical compositions of mudskippers (Pseudapocryptes elongatus (Curvier, 1816)

Abstract

Mudskipper Pseudapocryptes elongatus (Curvier, 1816) is one of the economic values for aquaculture in the Mekong Delta, Viet Nam. The aim of this study was to examine the effects of lipid enhancement on maturation culture of mudskipper P. elongatus in capture conditions. The assessment was focused on some key figures of growth performance, somatic indexes and biochemical compositions of broodstock. Adults mudskipper (50-60g/ind.) were fed with four dietary lipid levels for 90 days. The first diet was a basal diet (commercial feed) served as control diet without additional lipid (Diet 1_Control). For diet 2, 3, and 4, lipids were added to the control diet to boost final lipid levels of 9% (Diet 2_9%), 12% (Diet 3_12%), and 15% (Diet 4_15%) respectively. The results showed that a high survival rate (100%) was obtained in all treatments. There is no significant difference in growth performance of fish among diets. Simlarly, the GSI of fish did not differ significantly among treatments (P>0.05), while dietary lipid level of 12% and 15% promoted higher somatic indexes (GSI, HSI) and gonad development stage of mudskipper at 60 days and relatively decreased at the end of the trial. The highest HSI (7.90±0.35%) was found for those fish fed diet 4 and did not differ significantly compared to other treatments (P>0.05). In term of growth performance, a lipid efficiency ratio (1.61±0.29) was found in the control diet and differ significantly compared to other diets (P<0.05). Dietary lipid also affect on chemical composition of carcass body of broodstock. These results showed that lipids affected gonad development, HSI, and biochemical compositions of broodstock mudskippers and higher lipid level 9-12% would be recomded for broodstock culture in future.