Open AccessDietary niacin requirement of juvenile blunt snout bream Megalobrama amblycephala based on a dose–response study
Author(s) -
Li X.F.,
Wang T.J.,
Qian Y.,
Jiang G.Z.,
Zhang D.D.,
Liu W.B.
Publication year - 2017
Publication title -
aquaculture nutrition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.941
H-Index - 79
eISSN - 1365-2095
pISSN - 1353-5773
DOI - 10.1111/anu.12516
Subject(s) - niacin , megalobrama , nicotinamide , catfish , biology , zoology , medicine , endocrinology , weight gain , feed conversion ratio , biochemistry , body weight , fish <actinopterygii> , fishery , enzyme , gene
This study aimed to determine the optimal dietary niacin requirement of juvenile Megalobrama amblycephala . Fish, with an average weight of 3.62 ± 0.02 g, were randomly divided into six groups and fed six purified diets with graded levels of niacin (0, 10, 20, 30, 40 and 50 mg/kg) three times daily for 8 weeks. The survival rate, weight gain ( WG ), feed conversion ratio, protein efficiency and protein retention all significantly improved ( p < .05) as the dietary niacin level increased from 0 to 30 mg/kg but showed no significant difference ( p > .05) with further increases in niacin levels. The supplementation of 30 mg/kg niacin also led to a significant ( p < .01) reduction in the viscerosomatic index, hepatosomatic index and mesenteric fat index. The dietary niacin levels exhibited minimal effects on whole‐body moisture and ash content ( p > .05) but exerted a significant ( p < .05) influence on protein and lipid contents and liver nicotinamide concentrations with high values obtained in fish receiving greater than 30 mg/kg of niacin. In addition, moderate levels of niacin lowered plasma triglycerides, non‐esterified fatty acid and low‐density lipoprotein cholesterol concentrations ( p < .05). Based on the broken‐line regression analysis of WG and liver nicotinamide content, the optimal dietary niacin requirement of juvenile blunt snout bream was 31.25 and 30.62 mg/kg, respectively.