We evaluated whether triglyceride and glycogen levels in the liver of masu salmon Oncorhynchus masou fry were suitable indices of starvation. Triglyceride levels gradually declined during the spring for each of four groups in a hatchery (wild-origin fed fry, wild-origin unfed, hatchery-origin fed, and hatchery-origin unfed), as well as for hatchery-origin fry from a river, while glycogen levels did not. Triglyceride levels also declined gradually during winter for wild-originˆsh brought back to the hatchery, regardless of whether they were fed. Glycogen levels declined rapidly for thoseˆsh that were not fed. Regardless of the season, unfedˆsh began to die when triglyceride levels reached a level signiˆcantly lower than that found among fed fry or fry caught in the river. We conclude that triglyceride content is a useful index of hard starvation for underyearling masu salmon. In contrast, seasonal patterns must be considered before glycogen levels can be used as an index of starvation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.