Comparison of growth performance and biochemical components between low salinity tolerant hybrid and imported populations of Pacific white shrimp, Penaeus vannamei

Abstract

Penaeus vannamei, a high yield economical shrimp, is confronting germplasm degradation in the brine culture environments found in China. Genetic improvement by hybridization is an effective way to solve this problem. In this study, EB and CE hybrid was obtained from Guam wild B, C and E families from Shanghai Ocean University. EB and CE were used as parents to obtain genetic hybrids suitable for freshwater culture. The control group was shrimp imported from the Hainan Lutai Company. The two groups of shrimp were cultured for 3 months under salinities of 1‰, 5‰, and 15‰. Growth performance-related indicators, biochemical composition, and growth-related gene expression were examined. The results showed that at salinities of 1‰ and 5‰, the survival rate and growth performance of the low salt breeding group were better than those of the imported population. The digestive enzyme activity in the low salt breeding group was higher, which was consistent with its better growth performance, and was also associated with higher triglyceride, total cholesterol, and glycogen content. Lower levels of lactic acid indicated less anaerobic metabolism and better adaptability to the environment. The amino acid analysis of fatty acids showed that levels of essential amino acids and high unsaturated fatty acids were both higher in the low-salt breeding group than in the imported shrimp cultured in low salinity. The expression levels of genes associated with growth and hair removal were also higher in the low salt breeding group than in the imported shrimp group. The results indicated that the hybrid shrimp showed better growth performance and nutritional advantages compared with the imported shrimp under salinities of 1‰ and 5‰. This research provided a valuable reference for subsequent genetic breeding and shrimp culture.