Effects of yeast selenium on the growth and antioxidative performance in Litopenaeus vannamei

【Objective】The effects of dietary yeast selenium on the growth and antioxidant performance were studied in Litopenaeus vannamei. 【Method】Seven hundred and twenty healthy Litopenaeus vannamei with an initial average body mass of (0.41±0.01) g were randomly stocked into 6 groups with 3 replicates per group and 40 shrimps per replicate in re-circulated water system. The basal diet was supplemented with 0, 0.15, 0.30, 0.45, 0.60 and 1.00 mg·kg^-1 selenium (yeast selenium) respectively and these shrimps were fed with 6 semi-purified diets containing graded levels of 0.25, 0.41, 0.56, 0.68,0.84,1.20 mg·kg^-1 of selenium, respectively for 56 d.【Result and conclusion】The results showed that mass gain rate (MGR), specific growth rate (SGR), feed conversion rate (FCR), survival rate (SR) had no significant difference among all groups (P>0.05), but with the increase of yeast selenium levels, MGR and SGR increased and the highest value was found in the 0.84 mg·kg^-1 group. The total antioxidative capacity (T-AOC) and superoxide dismutase (SOD) of shrimp in hepstopsncreas were higher than those of the control group, while the malondialdehyde (MDA) content was lower than that of the control group. But there were no significant differences (P>0.05).A quadratic linear regression analysis showed that using MGR and SGR as response criteria in cultured condition, the optimum dietary selenium content for the highest growth in Litopenaeus vannamei was 0.98 mg·kg^-1 of dietary mass.