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Liu X.-H.,Key Laboratory of Healthy Mariculture for East China Sea | Liu X.-H.,South China Normal University | Ye J.-D.,Key Laboratory of Healthy Mariculture for East China Sea | Kong J.-H.,Key Laboratory of Healthy Mariculture for East China Sea | And 2 more authors.
North American Journal of Aquaculture | Year: 2012

Using 0.5% chromic oxide as an external indicator, apparent digestibility coefficients (ADCs) were determined for 12 protein feed ingredients (fish meal [FM], blood meal [BM], meat-and-bone meal [MBM], poultry byproduct meal [PBM], shrimp head meal [SHM], squid visceral meal [SVM], soybean meal [SBM], rapeseed meal [RM], cottonseed meal [CM], peanut meal [PM], corn gluten meal [CGM], and brewer's yeast [BY]) fed to Pacific white shrimp Litopenaeus vannamei (mean initial weight ± SD = 4.45 ± 0.21 g). The shrimp were randomly allocated to thirty-nine 150-L tanks (20 shrimp/tank) and were hand-fed a reference diet or test diet (70% reference diet and 30% test feed by weight) twice daily to satiation. Feces were collected by siphoning. The observed range of ADCs of the 12 ingredients was 48.6-87.0% for dry matter, 55.7-92.3% for crude protein, 2.1-92.5% for crude lipid, 52.1-79.9% for phosphorus, and 51.1-97.2% for gross energy. Relatively high ADCs were observed for dry matter in FM (87.0%) andMBM (76.5%); for crude protein in FM(90.9%), SBM (92.3%), and PM(88.8%); for crude lipid in FM (92.5%) and SVM (88.5%); and for phosphorus (79.9, 72.7, 72.5, and 78.5%) and gross energy (97.2, 82.3, 84.0, and 84.6%) in FM,MBM, PBM, and BY. The ADCs of amino acids for the 12 ingredients were 86.7-97.4% (FM), 58.4-98.8% (BM), 46.9-99.6% (MBM), 54.8-95.4% (PBM), 79.0-100.0% (SHM), 58.3-93.0% (SVM), 60.7-99.4% (SBM), 62.6-99.6% (RM), 52.9-91.4% (CM), 60.1-99.9% (PM), 15.6-97.8% (CGM), and 30.3-98.4% (BY). Fish meal, SBM, and PM showed high average ADCs for total amino acids (>90%). Crude protein ADCs corresponded with amino acid ADCs. Resultant digestibility data may provide more accurate information pertinent to formulating commercial feeds for Pacific white shrimp. © American Fisheries Society 2013.

Liu X.-H.,South China Normal University | Ye C.-X.,South China Normal University | Zheng L.-M.,South China Normal University | Ou C.-C.,South China Normal University | And 3 more authors.
Journal of the World Aquaculture Society | Year: 2015

A 60-d feeding trial was conducted to investigate the effect of dietary maize starch on growth performance, feed utilization, and apparent digestibility coefficient (ADC) and key hepatic enzyme activities regulating glycolytic and gluconeogenic metabolic pathways of juvenile obscure puffer, Takifugu obscurus (Abe) (initial body weight = 7.9±0.2g). Five isonitrogenous and isolipidic diets containing graded levels of maize starch (10, 15, 20, 25, and 30%) were formulated. Results demonstrated that weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER), protein productive value (PPV), and energy productive value (EPV) increased with increasing dietary maize starch up to 25% (P < 0.05), and thereafter WG, SGR, PER, PPV, and EPV declined. Hepatosomatic index and viscerosomatic index, plasma glucose, triglycerides, and liver glycogen and liver lipid concentration of fish significantly increased with increasing dietary maize starch level (P<0.05). ADC of starch reduced significantly up to 25%, while ADC of dry matter showed a contrary tendency. However, survival, whole body and muscle compositions, and ADCs of protein and lipid showed no significant differences. Dietary maize starch supplements tended to enhance gluconokinase and pyruvate kinase activities of the liver, but no significant differences were observed in activities of hexokinase, phosphofructokinase-1, fructose-1, 6-bisphosphatase, and glucose-6-phosphatase in the liver among dietary treatments. Based on WG and FCR, the appropriate dietary maize starch supplementations of juvenile obscure puffer were estimated to be 23.5 and 22.5% of diet, respectively. Copyright by the World Aquaculture Society 2015.

Liu X.-H.,South China Normal University | Ye C.-X.,South China Normal University | Ye J.-D.,Key Laboratory of Healthy Mariculture for East China Sea | Shen B.-D.,South China Normal University | And 2 more authors.
Fish Physiology and Biochemistry | Year: 2014

The effect of dietary amylose/amylopectin (AM/AP) ratio on growth, feed utilization, digestive enzyme activities, plasma parameters, and postprandial blood glucose responses was evaluated in juvenile obscure puffer, Takifugu obscurus. Five isonitrogenous (430 g kg-1 crude protein) and isolipidic (90 g kg-1 crude lipid) diets containing an equal starch level (250 g kg-1 starch) with different AM/AP ratio diets of 0/25, 3/22, 6/19, 9/16 and 12/13 were formulated. Each experimental diet was fed to triplicate groups (25 fish per tank), twice daily during a period of 60 days. After the growth trial, a postprandial blood response test was carried out. Fish fed diet 6/19 showed best growth, feed efficiency and protein efficiency ratio. Hepatosomatic index, plasma total cholesterol concentration, liver glycogen and lipid content, and gluconokinase, pyruvate kinase and fructose-1,6-bisphosphatase activities were lower in fish fed highest AM/AP diet (12/13) than in fish fed the low-amylose diets. Activities of liver and intestinal trypsin in fish fed diet 3/22 and diet 6/19 were higher than in fish fed diet 9/16 and diet 12/13. Activities of liver and intestinal amylase and intestinal lipase, and starch digestibility were negatively correlated with dietary AM/AP ratio. Fish fed diet 3/22 and diet 6/19 showed higher plasma total amino acid concentration than fish fed the other diets, while plasma urea nitrogen concentration and activities of alanine aminotransferase and aspartate aminotransferase showed the opposite trend. Equal values were found for viscerosomatic index and condition factor, whole body and muscle composition, plasma high-density and low-density lipoprotein cholesterol concentrations, and activities of lipase and hexokinase and glucose-6-phosphatase in liver. Postprandial plasma glucose and triglyceride peak value of fish fed diet 12/13 were lower than in fish fed the low-amylose diets, and the peak time of plasma glucose was later than in fish fed the other diets. Plasma glucose and triglyceride concentrations showed a significant difference at 2 and 4 h after a meal and varied between dietary treatments. According to regression analysis of weight gain against dietary AM/AP ratio, the optimum dietary AM/AP ratio for maximum growth of obscure puffer was 0.25. The present result indicates that dietary AM/AP ratio could affect growth performance and feed utilization, some plasma parameters, digestive enzyme as well as hepatic glucose metabolic enzyme activities in juvenile obscure puffer. © 2014 Springer Science+Business Media Dordrecht.

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