Growth, feed utilization, body composition and swimming performance of giant croaker,Nibea japonicaTemminck and Schlegel, fed at different dietary protein and lipid levels

Abstract

A 50‐day feeding trial was conducted to examine the effects of dietary protein and lipid levels on growth, feed utilization, body composition and swimming performance of giant croaker, Nibea japonica. Fish (initial body weight 44.6 g ind−1) were fed ten test diets which were formulated at 5 crude protein levels (360, 400, 440, 480 and 520 g kg−1) and 2 crude lipid levels (90 and 150 g kg−1). In addition, a raw fish diet (fillet of small yellow croaker) served as the reference. The weight gain (WG) increased, whereas the feed intake (FI) and feed conversion ratio (FCR) decreased, with increasing dietary protein level from 360 to 520 g kg−1. At the same dietary protein level, no significant difference was found in the WG between fish fed the diets containing 90 or 150 g kg−1 crude lipid. Fish fed the diet containing 480 g kg−1 crude protein and 90 g kg−1 crude lipid exhibited higher WG, nitrogen retention efficiency (NRE) and energy retention efficiency (ERE) but lower nitrogen wastes output (TNW). At the end of the feeding trial, the hepatosomatic index (HSI) and viscerosomatic index (VSI) decreased, whereas the body protein content increased, with increase in dietary protein level. The body lipid content was higher in fish fed at the 150 g kg−1 lipid level than in fish fed at the 90 g kg−1 lipid level. No significant difference was found in the maximum sustained swimming speed (MSS) between fish fed at different dietary protein and lipid levels. The WG, NRE, ERE and condition factor (CF) were higher, whereas the FI, FCR, HSI, VSI and TNW were lower, in fish fed the raw fish diet than in fish fed the diet containing 480 g kg−1 crude protein and 90 g kg−1 crude lipid. No significant difference was detected in the MSS between fish fed the raw fish diet and diet containing 480 g kg−1 crude protein and 90 g kg−1 crude lipid. The results of this study suggest that the suitable dietary crude protein and crude lipid levels are 480 g kg−1 and 90 g kg−1 for giant croaker reared in net pens.

Influence of dietary lipid on growth performance and body composition of the Gulf corvina, Cynoscion othonopterus

“…As expected, dietary energy increased from 17.50 to 23.10 kJ/g with increasing dietary lipid, but because the diets used in the present study were isoproteic, the dietary protein (P) to energy (E) ratio decreased, from 23.25 to 17.56 gP/MJ, as dietary lipid increased (Table 1). The experimental lipid level that elicited the best results for the Gulf corvina (11%) corresponds to a P/E ratio of 20.42 gP/MJ, which concurs with the range of P/E ratios, from 20.7 to 28.6 gP/MJ, known to produce optimal growth of other sciaenids, such as A. japonicus, A. regius, S. ocellatus, N. japonica, N. miichthioides, and Totoaba macdonaldi (Chai et al, 2013;Chatzifotis et al, 2012;Martínez-Llorens et al, 2011;McGoogan and Gatlin, 1999;Pirozzi et al, 2010;Rueda-López et al, 2011;Turano et al, 2002;Wang et al, 2006;Woolley et al, 2010) (values were either directly taken or calculated from dietary protein and energy content data reported by the authors). Comparable optimal P/E ratios also have been reported for other seawater carnivorous, non-sciaenid fish, such as Dentex dentex (19.5 gP/MJ for 10-g fingerlings, and 23.7 gP/MJ for 92.4-g juveniles), Lateolabrax japonicus (25.9 gP/MJ), Pleuronectes americanus (26.6 gP/MJ), and Rachycentrum canadum (22.4-28.8 gP/MJ) (Ai et al, 2004;Hebb et al, 2003;Skalli et al, 2004;Wang et al, 2005).…”

“…For the yellow croaker, Pseudosciaena crocea, Duan et al (2001) reported optimal dietary crude fat and protein levels to be 10.5 and 47%, respectively. In turn, Chai et al (2013) suggested dietary crude fat and protein levels of 9.0 and 48%, respectively, as optimal for the giant croaker, N. japonica. Finally, a diet combining 18% crude fat and 46% crude protein produced the best growth performance of juvenile A. japonicus (Woolley et al, 2010).…”

Protein-to-energy ratio of 21.43 g MJ−1improves growth performance of Nile tilapia at the final rearing stage under commercially intensive rearing conditions

“…; Chai et al . ), our results confirm that there is an optimum protein/energy ratio for tilapia diets in this phase.…”

Effects of dietary lipid levels on growth, feed utilization, body composition, fatty acid profiles and antioxidant parameters of juvenile chu’s croaker Nibea coibor

“…Energy levels of experimental diets (14.6-16.5 kJ/g) were achieved as previously described for giant croaker Nibea japonica (Lee et al 2001;Chai et al 2013). The gross energy value of each diet was determined by using values of 16.7 kJ/g protein, 16.7 kJ/g carbohydrate and 37.6 kJ/g lipid (Garling and Wilson 1976).…”

“…It classified in suborder Percoidei, family Sciaenidae and genus Nibea, and is distributed widely in India, the Philippines, and the South and East China Sea (Cheng Cheng 1987;Shen et al 2004). Chu's croaker is good candidate for aquaculture because it possesses some desirable characteristics including tolerance to widely varying salinity and temperatures (Chai et al 2013). In addition to its excellent local market of southeastern Asia attained as a result of the high tonic function of its swimming bladder, chu's croaker is also appreciated for its tasty flesh by foreign consumers.…”