Effects of dietary lipid level and feeding frequency on growth, body composition and lipid deposition in juvenile large yellow croaker(Larimichthys crocea)

An 8-week feeding trial in a 3×2 two-factorial design was conducted to study the effects of dietary lipid level(9%, 12% and 15%)and feeding frequency(one time or two times daily)on growth, body composition and lipid deposition in juvenile large yellow croakerinitial average weight(13.57±0.33)g.Compared with those fed once daily, fish fed two times daily had significantly higher final weight, specific growth rate(SGR), but lower feed efficiency ratio(FER)at each dietary lipid level(P < 0.05).When animals were fed two times daily, no significant difference was observed in the SGR and FER among dietary lipid levels(P > 0.05).However, SGR and FER of fish fed once daily increased significantly with the increase of dietary lipid contents(P < 0.05).Compared with that fed once daily, fish fed two times daily had significantly lower body moisture, but higher body crude lipid contents(P < 0.05), regardless of the dietary lipid levels.Body crude lipid contents of fish fed two times daily increased significantly with the increase of dietary lipid contents(P < 0.05).However, body crude lipid contents of fish fed once daily was not affected by dietary lipid contents(P > 0.05).Liver and muscle lipid contents, HSI and VSI were significantly affected by dietary lipid levels.When animals were fed two times daily, lipid contents in liver and muscle, HSI, and VSI increased significantly with the increase of dietary lipid level(P < 0.05).However, no significant difference was found in fish fed once daily(P > 0.05).Significant interactions of dietary lipid level and feeding frequency were only found in growth and FER(P < 0.05), but not in HSI, VSI, body composition and lipid contents in liver and muscle(P > 0.05).