Effects of Different Dietary Carbohydrate/Lipid Ratios on Growth, Feed Utilization and Body Composition of Early Giant Grouper Epinephelus Lanceolatus Juveniles

Abstract

An 8-week growth trial was undertaken to determine effects of different dietary carbohydrate (CHO)/lipid (L) ratios on growth, feed utilization and body composition of early giant grouper Epinephelus lanceolatus juveniles. Five isoenergetic (4.1 kcal/g) and isonitrogenous (50% CP, dry-matter basis) experimental diets were formulated to contain different crude lipid (CL) levels (22%, 19.8%, 17.6%, 15.4% or 13.2%, dry-matter basis) and together different corn starch levels (0%, 4.95%, 9.9%, 14.85% or 19.8%), thereby forming different dietary CHO/L ratios. Groups of 41 early giant grouper juveniles (average initial weight of 0.397 g/fish) were stocked into small floating cages (L 120 cm × W 70 cm × H 50 cm). Triplicate groups of fish were fed each dietary treatment three times daily to apparent satiation.

Effects of different dietary carbohydrate‐to‐lipid ratios on growth, plasma biochemical indexes, digestive and immune enzymes activities of juvenile orange‐spotted grouper Epinephelus coioides

“…The results of the present study were higher than those reported by some previous studies, such as studies on giant grouper (Li & Wu, 2016) and orange-spotted grouper (Wang, Han, et al, 2017).…”

“…The results of the giant grouper (Li & Wu, 2016) study used WGR as the evaluation index and corn starch as the CHO source, and the optimal CHO:L ratio was 1.30, corresponding to a dietary crude lipid content of 14.79% and a dietary CHO content of 19.23%. This result was much smaller than the results of this study, probably because the CHO sources used in the experiment were different.…”

“…The nutrient requirements of some groupers have been investigated (Li, Li, Chen, Jin, & Zhang, 2019;Li & Wu, 2016;Luo et al, 2004;Luo et al, 2005;Tuan & Williams, 2007;Wang, Han, et al, 2017;Wang et al, 2016), and Suwirya, Giri, and Marzuqi (2004) reported that the humpback grouper (Cromileptes altivelis) could effectively utilize medium levels (20%) of dextrin, while the red-spotted grouper (Epinephelus akaara) (Wang et al, 2016) showed the best growth rate with a diet of 6% corn starch level.…”

Effects of different dietary carbohydrate on growth performance and liver histology of Nile tilapia, Oreochromis niloticus fingerlings

“…No effect of carbohydrate sources or levels were recorded on body contents of tilapia. Similar results were obtained in different species: tilapia [27,34] , trout [35] and grouper [3,36] . On the contrast, a positive increase in lipid contents by increase carbohydrate levels were recorded in other fish species such as trout (Salmo gairdneri) [26] and catfish (Clarias gareipinus) [37,38] .…”

“…Enough amount of carbohydrate would enhance growth performance and immunity [2,3,4] . Besides, carbohydrate of starch origin is crucial in improving feed physical quality with good binding and expansion properties [5] .…”