Seasonal and Environmental Effects on the Lipid Composition ofNeomysis Integer

Abstract

During the last 3 years a survey of marine lipids has been in progress in this laboratory. Several classes of marine animals have been analysed for their fatty-acid composition. These results have shown a considerable species variation but no estimate could be made of the effect of season and environment. It was therefore decided to choose an inshore animal, which could be readily collected, and to examine its lipid composition with regard to seasonal and environmental changes.The brackish-water, partly planktonic mysid,Neomysis integer(Leach), was selected. This species has already been the subject of much biochemical study (Raymont, Austin & Linford, 1964, 1966, 1968; Linford, 1965), in which the three major fractions protein, lipid and carbohydrate were examined. The lipid weight was found to be low in comparison with the protein content. Also, significant decreases in the lipid were found in November, January and March. It was concluded thatN. integerstored little lipid as a metabolic energy reserve, and as the carbohydrate was low, protein may be catabolized. Only one sample analysis for fatty-acid composition was reported.The marine speciesNeomysis nakazaviaihas been investigated by Yamada (1961), but unfortunately an ether extract was taken from sun-dried material and so the results are not comparable with the present work onNeomysis integer.In the present study the saponifiable fraction of the lipid is examined in more detail in an attempt to establish the relative importance of the factors of season, temperature and salinity upon the fatty-acid composition.