Changes in Chemical Composition of Central British Columbia Pink Salmon During Early Sea Life
Changes taking place in body composition of juvenile pink salmon during early sea life were studied. Under the natural conditions obtained in 1963 and 1964 the fish became relatively more obese as they grew to a length of 7.5 cm. Further growth in weight was isometric with growth in length. Water pr...
Published in: | Journal of the Fisheries Research Board of Canada |
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Main Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Canadian Science Publishing
1966
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Subjects: | |
Online Access: | http://dx.doi.org/10.1139/f66-125 http://www.nrcresearchpress.com/doi/pdf/10.1139/f66-125 |
Summary: | Changes taking place in body composition of juvenile pink salmon during early sea life were studied. Under the natural conditions obtained in 1963 and 1964 the fish became relatively more obese as they grew to a length of 7.5 cm. Further growth in weight was isometric with growth in length. Water progressively became a lesser proportion of total weight until 7.5 cm length, thereafter it remained an approximately constant proportion. A diurnal fluctuation in body moisture was noted, and was correlated with a diurnal feeding cycle. Protein, in respect to length, showed positive allometry throughout the size range studied but an inflection in the allometric line was noted at about 5.5 cm. Relative lipid weight is postulated to be basically correlated with protein but reflected the longer-term changes in amount of food ingested. A shift from high to low lipid content occurred at the end of May. This shift was independent of food ingested, independent of size per se, and occurred at the beginning of a migratory stage. Experimentally, the first reaction to severely restricted food supply was loss of lipid and moisture. Protein was catabolically consumed under more prolonged periods of starvation. At less severe conditions, lipid was lost but the body weight, was maintained by uptake of water. |
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