The influence of dietary fatty acids and environmental temperature on the fatty acid composition of teleost fish

Abstract

Marine and fresh water fish were depleted of tissue unsaturated fatty acids to various degrees and subsequently presented with linoleic and linolenic acids at different dietary levels, at different temperatures, with and without other dietary fat.Examination of the tissue fatty acids demonstrated that marine and fresh water fish do not differ between themselves or from other classes of animals in the following basic mechanisms of deposition and interconversions of dietary fatty acids: The fish are readily depleted of tissue polyunsaturated fatty acids. Dietary linoleic and linolenic acids are deposited, the former to a greater degree than the latter. At high levels of linoleic or linolenic acids in the diet there is no significant degree of their conversion to the longer chain more highly unsaturated acids typical of marine oils. At low levels of linoleic or linolenic acids in the tissues there is a significant, but slight, conversion to the longer chain acids at low environmental temperatures. The increase in the level of linoleic acid in tissue lipids which accompanies increases in the dietary levels, quickly tapers off above dietary levels of 5%. Temperature differences between 13 and 23C had little or no influence on the deposition or interconversion of polyunsaturated acids. Dietary cottonseed oil, which contains cyclopropene fatty acids, produces an increase in tissue stearic acid in the fundulus.

Nutritional Evaluation of Lipids in Fish from Temperate Australian Waters

“…Decreases in PUFA concentrations in lipids would therefore be expected in warmer waters (nearer the equator). Latitude-dependence of the AA concentration (Sinclair et al, 1984;Evans et al, 1986) and the ratio of polyunsaturated to saturated fatty acids (P/S) has been established (Reiser et al, 1963). This may explain the difference in lipid AA content noted by Brown et al (1989).…”

The component fatty acids of the lipids of some species of marine and freshwater molluscs

“…However, in contrast to fish, the amount of linoleic acid (18:2) in the fat of the freshwater mollusc was similar to that in the marine species. The observed differences in fatty-acid distribution patterns between the molluscs from the two types of aquatic environment probably arise from a combination of taxonomic and of ecological factors, of which the lipid composition of the dietary organism is almost certainly the most important (see, for example, Reiser et al 1963).…”

Does overwinter temperature affect maternal body composition and egg traits in yellow perch Perca flavescens?

“…Beyond physical size, the biochemical composition of eggs is mediated through maternal provisioning and somatic energy reserves and may be influenced by the maternal thermal environment (Henderson, 2000;Izquierdo et al, 2001;Henrotte et al, 2010). Cooler temperatures appear to increase the amounts of essential n-3 and n-6 polyunsaturated fatty acids in both maternal tissues and eggs in several species (Reiser et al, 1963;Knipprath & Mead, 1966;Tidwell et al, 1999;Alhazzaa et al, 2013), consistent with the hypothesis of homeoviscous adaptation, in which the lipid composition of cell membranes is adjusted to maintain fluidity and function in cold temperatures (Dey et al, 1993). Such variation in egg size and egg biochemical composition can have important influences on larval size and survival, as larger eggs containing more lipids or essential fatty acids result in larger larvae that exhibit increased starvation resistance, swimming ability and overall survival (Berkeley et al, 2004;Yanes-Roca et al, 2009;Andree et al, 2015;Perez & Fuiman, 2015).…”