Effects of dietary protein and lipid levels with different protein‐to‐energy ratios on growth performance, feed utilization and body composition of juvenile red‐spotted grouper, Epinephelus akaara. (7th February 2017)

• Record Type: Journal Article
• Authors: Wang, J.T.; Han, T.; Li, X.Y.; Yang, Y.X.; Yang, M.; Hu, S.X.; Jiang, Y.D.; Harpaz, S.
• Is Part Of: Aquaculture nutrition. Volume 23:Number 5(2017:Oct.)
• Page Start: 994
• Page End: 1002
• Publication Date: 2017-02-07
• Subjects: body composition -- dietary protein and lipid -- growth performance -- protein‐to‐energy ratio -- red‐spotted grouper Epinephelus akaara; Aquaculture -- Periodicals; Aquatic animals -- Feeding and feeds -- Periodicals; Fishes -- Feeding and feeds -- Periodicals; 639.3
• DOI: 10.1111/anu.12467
• Languages: English
• ISSNs: 1353-5773

Abstract

Abstract: An 8‐week feeding trial was conducted to assess dietary protein and lipid levels on growth performance, feed utilization and body composition of juvenile red‐spotted grouper (7.85 ± 0.03 g fish −1 ). Nine semi‐purified diets were formulated containing varying protein levels (440–520 g kg −1, dry matter) and lipid levels (60–120 g kg −1, dry matter). The weight gain of juvenile Epinephelus akaara was affected by dietary protein ( p = .005) and its interaction with dietary lipid ( p = .020). Viscerosomatic index, intraperitoneal fat ratio and whole‐body lipid level increased with increasing dietary lipid level ( p < .001). Nitrogen retention was not affected by dietary protein and lipid, while lipid retention decreased with increasing dietary lipid level ( p < .001). The plasma blood urea nitrogen increased with increasing dietary protein level ( p = .003). This study showed that diet with 520 g kg −1 protein and 60 g kg −1 lipid with 30.58 mg kJ −1 P:E provided a maximal growth for this species. Moreover, an increase in dietary lipid levels (from 60 to 90 g kg −1 ) could reduce the protein requirement (from 520 to 480 g kg −1 ) without affecting the growth performance, while higher fat deposition was observed in fish fed high‐lipid diets.