STUDIES ON THE CHARACTERISTIC INDICATION OF NUTRITIVE VALUE FOR DIETARY PROTEIN IN FISH

Research Project

Project/Area Number	63480072
Research Category	Grant-in-Aid for General Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	Fisheries chemistry
Research Institution	TOKYO UNIVERSITY OF FISHERIES
Principal Investigator	WATANABE Takeshi TOKYO UNIVERSITY OF FISHERIES, DEPARTMENT OF AQUATIC BIOSCIENCES, PROFESSOR, 水産学部, 教授 (60017051)
Co-Investigator(Kenkyū-buntansha)	TAKEUCHI Toshio TOKYO UNIVERSITY OF FISHERIES, DEPARTMENT OF AQUATIC BIOSCIENCES, ASSOCIATE PROF, 水産学部, 助教授 (70092591) MURAI Takeshi NATIONAL RESEARCH INSTITUTE OF FISHERIES SCIENCE, RESEARCH COORDINATOR OF RESOUR, 水産研究官室, 研究官
Project Period (FY)	1988 – 1989
Project Status	Completed (Fiscal Year 1989)
Budget Amount *help	¥6,700,000 (Direct Cost: ¥6,700,000) Fiscal Year 1989: ¥1,300,000 (Direct Cost: ¥1,300,000) Fiscal Year 1988: ¥5,400,000 (Direct Cost: ¥5,400,000)
Keywords	DIET / PROTEIN / CARP / RAINBOW TROUT / TILAPIA / AYU / DIGESTIBLE CRUDE PROTEIN / AMINO ACID / テラピア / 可消化タンパク / 原料
Research Abstract	The digestible crude protein (DCP) content of various feedstuffs such as white fish meal, brown fish meal, meat meal, silkworm pupa meal, soybean meal, corn gluten meal, defatted wheat germ meal, defatted rice bran, and wheat flour were determined with carp, Tilapia,Ayu and rainbow trout under various conditions in terms of fish size and water temperature. The digestibility of protein in various ingredients was found to be not so much influenced by fish aize (2-200g) bot a little water temperature. The DCP content of diets prepared by mixing various ingredients in different ratios was also found to agree between two values; one calculated based on the DCP of each ingredient and the other determined by the indirect method using diets containing chromium oxide as an indicator. In order to study portal absorption and hepatic uptake of amino acids in rainbow trout force-fed complete diets containing casein or crystalline amino acids, blood samples were collected from the hepatic portal vein and caudal vein-artery complex at 0, 3, 6, 12, 24, and 48 h after force -feeding complete diets. In both dietary groups, a large proportion of free amino acids appeared in the portal blood within 3h and their level reached peaks by 12h at the latest and dropped to fasting levels by 24h. Patterns of the portal absorption of free essential amino acids reflected the dietary profiles in both groups during the absorptive period. These results suggested that DCP must be very good characteristic indication of nutritive value of dietary protein In fish and postprandial changes in plasma free amino acids were also effective indicator for nutritive value for protein of semipurified diets.