Effect of dietary methionine on growth performance, lipid metabolism and antioxidant capacity of large yellow croaker (Larimichthys crocea) fed with high lipid diets

• Published in: Aquaculture Vol. 536; p. 736388
• Main Authors: Li, Jiamin, Xu, Wenxuan, Lai, Wencong, Kong, Adong, Zhang, Zhou, Pang, Yuning, Wang, Zhen, Shentu, Jikang, Wu, Xiongfei, Mai, Kangsen, Ai, Qinghui
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.04.2021
• Subjects: Antioxidant capacity; Growth performance; Large yellow croaker; Lipid metabolism; Methionine; Antioxidant capacity; Lipid metabolism; Growth performance; Methionine; Large yellow croaker
• ISSN: 0044-8486; 1873-5622
• DOI: 10.1016/j.aquaculture.2021.736388

A 10-week feeding trial was conducted to evaluate the effect of dietary methionine (MET) on the growth performance, lipid metabolism and liver antioxidant function in juvenile large yellow croaker (Larimichthys crocea) fed with high lipid diets (HLDs). Large yellow croaker with an initial average weight of 8.59 g, were fed with basic HLD (lipid level at 18%, HL), basic HLD supplemented with 0.6% MET (HL/L-MET) and basic HLD supplemented with 1.2% MET (HL/H-MET). Results indicated that dietary MET did not affect weight gain, specific growth rate and feed efficiency ratio (P > 0.05). The MET supplementation in large yellow croaker also did not affect the content of total lipid in whole body (HL = 9.57, HL/L-MET = 8.92 and HL/H-MET = 8.71%), liver (7.34, 16.68 and 14.37%) and muscle (10.87, 12.11 and 9.94%) (P > 0.05). However, MET supplementation reduced the size and number of liver lipid droplets as dietary MET increased. Meanwhile, supplementation of MET in HLDs reduced serum total cholesterol (2.65, 2.14 and 1.91 mmol/L), low-density lipoprotein-cholesterol (0.27, 0.21 and 0.16 mmol/L) and triglyceride (4.80, 2.43 and 1.96 mmol/L) (P < 0.05), but increased serum high-density lipoprotein-cholesterol (0.68, 0.77 and 0.83 mmol/L) (P < 0.05). Dietary MET upregulated significantly the mRNA expression of genes related to mitochondrial fatty acid β-oxidation (PPARα and CPT1) and ER stress (GRP78, ATF6α and CHOP) (P < 0.05). Furthermore, feeding fish with MET diets reduced serum alanine transaminase and aspartate transaminase activities, serum and liver malondialdehyde content, and liver 8-hydroxydeoxyguanosine level. Interestingly, feeding fish with MET diets increased liver total antioxidant capacity activity (P < 0.05). In conclusion, dietary MET improved lipid metabolism and increased antioxidant capacity in the liver, but did not affect growth performance in juvenile large yellow croaker fed with HLDs. •Dietary methionine could not affect growth performance.•Dietary methionine decreased serum lipid profile, but not liver fat deposition.•Dietary methionine upregulated gene expression of mitochondrial FA β-oxidation.•Dietary methionine increased gene expression of endoplasmic reticulum stress.•Dietary methionine reduced liver damage and improved hepatic anti-oxidative defenses.