Effects of dietary carbohydrate/lipid ratios on growth performance, body composition and glucose metabolism of fingerling blunt snout breamMegalobrama amblycephala

Abstract

This study aimed to investigate the optimum dietary carbohydrate/lipid (CHO/L) ratio for fingerling blunt snout bream Megalobrama amblycephala (average initial weight: 6.61 AE 0.03 g). Six isonitrogenous and isoenergetic diets were formulated to contain various CHO/L ratios ranging from 1.62 to 24.20. Each diet was tested in four replicates for 10 weeks. Specific growth rate (SGR), feed conversion ratio and nitrogen and energy retention all improved significantly (P < 0.05) as dietary CHO/L ratios decreased from 24.20 to 5.64 but showed little difference (P > 0.05) as dietary CHO/L ratios ranged from 2.45 to 5.64. Hepatosomatic index increased significantly (P < 0.05) as dietary CHO/L ratios increased, whereas intraperitoneal fat ratio showed an opposite trend (P < 0.05). Opposite to moisture content, lipid content of whole body and carcass all increased significantly (P < 0.05) as dietary CHO/L ratios decreased. Liver lipid content showed little difference (P > 0.05) among all the treatments, while liver glycogen content increased significantly (P < 0.05) with increasing CHO/L ratios. High dietary carbohydrate enhanced the activities of liver hexokinase, pyruvate kinase and glucose-6-phosphate dehydrogenase but did not induce hyperglycaemia. Based on the second-order polynomial regression analysis of SGR, the optimal dietary carbohydrate and lipid contents for fingerling blunt snout bream were 291.7 and 81.4 g kg À1 , respectively, with a corresponding dietary CHO/L ratio of 3.58.

Effects of dietary carbohydrate/lipid ratios on growth, body composition, and nutrient utilization of hybrid catfish (Pseudoplatystoma reticulatum x Leiarius marmoratus)

“…According to Li et al (2013), fingerling blunt snout bream (Megalobrama amblycephala) has a better ability to utilize dietary lipids than carbohydrates and also shows a protein-sparing effect of dietary lipid. However, excessive dietary lipids may cause lipid deposition both in muscle and visceral adipose tissue, but not in the liver.…”

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

“…Based on the best growth performance or health status, suitable dietary CHO/Lipid ratios have been established in some fish species such as walking catfish (3.38) [8] blunt snout bream (3.58) [13], yellow catfish (2.45-5.58) [14] and yellowfin seabream (0.62) [15].…”

Sustained swimming improves fish dietary nutrient assimilation efficiency and body composition of juvenile Brycon amazonicus

“…While in fish living under motionless water the protein surplus would likely lead to muscular fat, in exercised ones its deposition was amplified. However, prior to the swimming physical efforts, some fish species accumulated lipids whenever they were fed with nutrients in excess (Felip et al, 2012;Li et al, 2013). Therefore, the body composition changes observed in fish under SS are not always the same, since many factors, such as diet quality, feeding practices, fish species, swimming intensity and span can be involved (Davison, 1997;Yogata and Oku, 2000;Felip et al, 2013).…”