A comparative chemical study on population-specific odorants from atlantic salmon

Abstract
Samples of skin mucus and intestinal contents were collected from groups of salmon presmolt from three Norwegian rivers. The supernatants obtained after precipitation were gel-filtered on a Sephadex G-25 column, which revealed peaks with absorption at 280 nm. Fractions incorporating a group of retarded peaks were examined by two-dimensional thin-layer chromatography. The spots obtained on the thin-layer plates were sorted out by means of position, intensity, and fluorescence properties.R f values for the assumed identical spots from each group were subjected to statistical analysis. In one of the chromatography systems, 8 spots of 24 from samples of skin mucus and 6 spots of 27 from intestinal contents show larger standard deviations (SD) ofR f than may be expected when a substance is chromatographed repeatedly. These SDs fit a linear relationship of SD to chromatography length by a probability of less than 0.01. The results indicate a molecular variation between the groups which could be a source for population-specific odorants. If these substances are used in chemical communication, they can provide the specific clues needed for a successful return to the home river.