Effects of Lactic Acid Bacteria on Growth,Non-specific Immunity and Stress Resistance of Pacific White Shrimp,Litopenaeus vannamei

Key words: 
• Litopenaeus vannamei /
• lactic acid bacteria /
• growth performance /
• non-specific immunity /
• stress resistance

Abstract: Two strains of the genera Lactobacillus of bacteria,Weissella confusa（LAB041） and Lactobacillus plantarum（LAB1036）,isolated from Dross vinegar in Hainan were used to feed healthy larvae（20 days old） of Pacific white shrimp,Litopenaeus vannamei,to observe their effect on growth performance,non-specific immunity and stress resistance of the Pacific white shrimp.The results showed that the survival rate,final length,weight gain percentage and specific growth rate of the pacific white shrimp treated after 8 weeks were significantly higher in the LAB041 group than in the control group（P＜0.05）.There was significantly lower feed conversion ratio in the LAB041 and LAB1036 groups than in the control group（P＜0.05）.The results of non-specific immunity parameters showed that the Pacific white shrimp fed the diets containing W.confusa（LAB041） had significantly higher activity of total antioxidant capacity（T-AOC） and acid phosphatase（ACP） than the control group（P＜0.05）,and significantly lower superoxide dismutase（SOD） activity than the control group（P＜0.05）.The results of stress resistance experiment show that feeding the diets containing LAB1036 improved the tolerance of the Pacific white shrimp to nitrite and low level of salinity.However a single factor analysis of variance showed that there was no significant difference in mortality between the groups（P＞0.05）.Feeding the diets containing LAB041 and LAB1036 significantly reduced the tolerance of shrimp to high salinity（P＜0.05）.