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M.C. Nesheim

Publications and source records attributed to M.C. Nesheim.

3 recordsLinked to original sources
USGS1984

Effects of dietary excesses of branched-chain amino acids on the metabolism and tissue composition of lake trout ( Salvelinus namaycush )

1. Excesses of either leucine, isoleucine or valine were fed in separate experiments to determine if the branched-chain amino acid antagonism reported in other animals occur in trout ( Salvelinus namaycush ). 2. Parameters measured include growth rate, feed utilization efficiency, plasma and muscle-free amino acids, carcass composition and branched-chain amino acid aminotransferase. 3. Dietary excesses of leucine or isoleucine caused an increase in the valine requirement. 4. The inability of leucine and isoleucine supplementations to ameliorate the effects of excess dietary valine are interpreted as a valine toxicity rather than an antagonism.

Comparative Biochemistry and Physiology, Part A: P↗
USGS1983

Dietary requirements for essential branched-chain amino acids by lake trout

In a 12‐week growth study of the dietary requirements of young lake trout Salvelinus namaycush for essential branched‐chain amino acids, the leucine requirement was between 2.74 and 3.66%, and the isoleucine requirement between 1.54 and 2.06%, of dietary protein (as‐fed basis). These ranges are substantially lower than those published and widely used in formulation of salmonid feeds. On the basis of both growth criteria and concentration of free amino acids in blood plasma, the valine requirement was within the range of 1.77 to 2.23% of dietary protein. The upper value of this range is substantially lower than the requirement reported for chinook salmon Oncorhynchus tshawytscha. Plasma valine concentrations in lake trout responded to dietary supplements of valine above the requirement level; the concentrations increased sharply once the requirement was exceeded. This finding is similar to observations recorded in other animals.

Transactions of the American Fisheries Society↗