Premium
Effects of different dietary vitamin C supplementations on growth performance, mucus immune responses and antioxidant status of loach ( Misgurnus anguillicaudatus Cantor) juveniles
Author(s) -
Zhao Yan,
Zhao Jiaxing,
Zhang Yin,
Gao Jian
Publication year - 2017
Publication title -
aquaculture research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.646
H-Index - 89
eISSN - 1365-2109
pISSN - 1355-557X
DOI - 10.1111/are.13231
Subject(s) - biology , antioxidant , ascorbic acid , catalase , glutathione peroxidase , superoxide dismutase , zoology , lipid peroxidation , vitamin , feed conversion ratio , medicine , vitamin c , endocrinology , food science , biochemistry , body weight
A 60‐day feeding trial was conducted to determine the effects of different dietary vitamin C levels on growth performance, immune response and antioxidant capacity of loach juveniles. Six isonitrogenous (58.6% of crude protein), isoenergetic (17.5 kJ g −1 ) practical diets supplemented with 0 ( VC 0), 100 ( VC 100), 200 ( VC 200), 500 ( VC 500), 1000 ( VC 1000) and 5000 mg kg −1 ( VC 5000) of VC (35% ascorbic acid equivalent) were fed to fish (mean initial weight 0.11 ± 0.02 g) in triplicate. Results showed that fish fed VC 0 diet had significantly lower body weight gain ( BWG ) and survival rate ( SR ). However, BWG and SR improved significantly in fish fed VC 100 and VC 200 diet respectively. Whole body ascorbic acid concentration increased with incremental dietary VC levels from 0 to 100 mg kg −1 . The activity of mucus alkaline phophatase was significantly increased by the dietary VC level. Incremental levels of VC significantly reduced activities of glutathione peroxidase ( GP x) and catalase. Moreover, fish fed diets containing more than 100 mg kg −1 VC significantly down‐regulated the superoxide dismutase and GP x mRNA expression in liver. Meanwhile, the expressions of liver heat shock protein ( HSP 70 ) and nuclear factor‐erythroid 2‐related‐2 ( Nrf2 ) were affected by fish fed diets containing VC from 100 to 5000 mg kg −1 . In conclusion, VC requirement of loach juveniles for optimum growth and functionally preventing lipid peroxidation was more than 200 mg kg −1 of diet. Moreover, high dose of VC supplementation did not show any detrimental effects on loach growth performance.