Verification of protein sparing by feeding carbohydrate to common carp Cyprinus carpio

• Published in: Chinese journal of oceanology and limnology Vol. 35; no. 2; pp. 251 - 257
• Main Author: 程镇燕 李静辉 张宝龙 方珍珍 孙金辉 白东清 孙金生 乔秀亭
• Format: Journal Article
• Language: English
• Published: Heidelberg Science Press 01.03.2017; Springer Nature B.V
• Subjects: Aquaculture; Biochemical composition; Biology; Body composition; Body weight; Body weight gain; Cages; Carbohydrates; Carp; Conversion ratio; Corn; corn starch; Cyprinus carpio; Diet; dietary carbohydrate; Earth and Environmental Science; Earth Sciences; Enzymatic activity; Enzyme activity; Feed conversion; Feeding experiments; Fish; Food conversion; Freshwater; Freshwater fishes; Gene expression; Glucokinase; Glucose; glucose 6-phosphate; growth performance; Growth rate; Hexokinase; Inland water environment; Lipid composition; Lipids; Marine; Metabolism; Nutrient deficiency; Oceanography; Phosphates; protein efficiency ratio; Proteins; Pyruvate kinase; Pyruvic acid; specific growth rate; Starch; Vegetables; weight gain; 摄食; 玉米淀粉; 碳水化合物; 葡萄糖激酶; 蛋白质效率; 饲料转化率; 验证; 鲤鱼; protein sparing; growth performance; glucose metabolism; corn starch; common carp
• ISSN: 0254-4059; 2096-5508; 1993-5005; 2523-3521
• DOI: 10.1007/s00343-016-5332-6

A 9-week feeding trial in floating freshwater cages （1.0 m× 1.0 m×2.0 m） was conducted to study the effects of different dietary levels of protein and starch on growth, body composition, and gene expression of enzymes in common carp, Cyprinus carpio （mean body weight, 36.12±1.18 g） to evaluate the protein-sparing effect of dietary carbohydrate. Four diets were formulated with corn starch as the carbohydrate source to obtain corn starch levels of 6.5%, 13%, 19.5%, or 26% and protein levels of 30.5%, 28.2%, 26.4%, and 24.2%. The results showed no differences in growth performance of fish fed the diets with different protein and corn starch levels, but body composition and glucose metabolic enzyme activity of carp were significantly affected by the different diets （P〈0.05）. Weight gain, specific growth rate, and the feed conversion ratio were not different in fish fed the different dietary treatments. Protein efficiency ratio increased significantly as corn starch level increased （P〈0.05）. Whole-body crude lipid composition increased with increasing dietary corn starch level （P〈0.05）. Glucokinase （GK）, hexokinase, and pyruvate kinase （PK） activities increased significantly with increasing dietary corn starch level （P〈0.05）, whereas glucose-6-phosphate （G6Pase） activity decreased with increasing dietary corn starch level （P〈0.05）. GK gene expression was significantly higher in fish fed the high-corn starch diet than those fed the low-corn starch diet （P〈0.05）. G6pase gene expression tended to decrease with increasing starch level （P〉0.05）. In summary, the results indicate a protein-sparing effect by substituting carbohydrate in the diet of common carp.