Journal of Aquaculture Research & Development

Abstract

Growth Performance, Lipid Deposition and Hepatic Lipid Metabolism Related Gene Expression in Schizothorax prenanti fed with Dietary Acidolysis-Oxidized Konjac Glucomannan Supplementation

Yinglong Wu

The present study was conducted to investigate the effects of dietary acidolysis-oxidized konjac glucomannan (A-OKGM) (0, 0.4, 0.8 and 1.6%) supplementation on the growth performance, lipid metabolism of Schizothorax prenanti, a commonly cultured freshwater fish in inland China. The 1.6% A-OKGM diet significantly improved weight gain (WG) (P<0.05). Triglycerides (TG) content in both serum and liver was significantly increased when diets supplemented with A-OKGM, regardless of inclusion level (P<0.05). The total cholesterol (TC) and LDL-cholesterol (LDL-C) levels in serum were significantly increased when fish fed with 0.4%, 1.6% A-OKGM diets (P<0.05). However, only 1.6% A-OKGM diet significantly increased HDL-cholesterol (HDL-C) level (P<0.05). Dietary 1.6% A-OKGM supplementation had a significant effect on glucose level in the serum (P<0.05). However, the activities of phosphoenolpyruvate carboxykinase (PEPCK) and hexokinase (HK) were significantly decreased by both 0.8% and 1.6% A-OKGM diets (P<0.05). A-OKGM diets significantly affected glucose-6-phosphate dehydrogenase (G6PD) and total lipase activity of Schizothorax prenanti, regardless of inclusion level (P<0.05). The lipid content in the liver was significantly increased by A-OKGM diets, regardless of inclusion level (P<0.05). Moreover, A-OKGM diets significantly up-regulated the mRNA levels of lipogenic genes (PPARγ, FAS, ACCa, FABP, GPDH and HMGCR), regardless of inclusion level (P<0.05). The expression of CPT1 in fish fed with 1.6% A-OKGM diet was significantly lower than that of control group (P<0.05). These results encourage conducting further research on the administration of A-OKGM and other prebiotics in Schizothorax prenanti.