Influence of dietary linoleic acid on egg fatty acid composition in hens deficient in essential fatty acids

1968 ◽  
Vol 19 (5) ◽  
pp. 266-269 ◽  
Author(s):  
D. Balnave
1972 ◽  
Vol 71 (1) ◽  
pp. 62-72 ◽  
Author(s):  
Knut Kirkeby

ABSTRACT The fatty acid composition of cholesterol esters, phospholipids, and triglycerides of the serum has been studied in groups of hyperthyroid and hypothyroid women and also in control material matched for age. In hyperthyroidism, a decrease in the proportions of linoleic acid and an increase in the proportions of some saturated and mono-unsaturated fatty acids were observed. When absolute concentrations were considered, it appeared that the decrease in linoleic acid was almost equivalent to the entire decrease in total fatty acids in the serum of the hyperthyroid patients. In hypothyroidism no changes were noted in the proportions of linoleic, saturated and mono-unsaturated fatty acids, and the absolute concentrations reflected the general increase in serum lipids. It is believed that these findings may be explained by the changes in lipid turnover which are known to occur in disturbances of thyroid function. In hyperthyroidism, they lead to a linoleic acid deficiency, while a sparing effect must be operating in hypothyroidism. The finding of relatively high linoleic acid values combined with hyperlipaemia in hypothyroidism seems to be characteristic of the condition, since other types of hyperlipaemia are almost invariably combined with low percentages of linoleic acid. Results regarding arachidonic and eicosatrienoic acid are consistent with increased synthesis in hyperthyroidism, and decreased synthesis in hypothyroidism.


2011 ◽  
Vol 59 (6) ◽  
pp. 369 ◽  
Author(s):  
A. J. Hulbert ◽  
Sarah K. Abbott

There are four types of fatty acids but only two types are essential nutritional requirements for many animals. These are the omega-6 polyunsaturated fatty acids (n-6 PUFA) and the omega-3 polyunsaturated fatty acids (n-3 PUFA) and because they cannot be converted to one another they are separate essential dietary requirements. They are only required in small amounts in the diet and their biological importance stems largely from their role as constituents of membrane lipids. They are synthesised by plants and, as a generalisation, green leaves are the source of n-3 PUFA while seeds are the source of n-6 PUFA in the food chain. While the fatty acid composition of storage fats (triglycerides) is strongly influenced by dietary fatty acid composition, this is not the case for membrane fats. The fatty acid composition of membrane lipids is relatively unresponsive to dietary fatty acid composition, although n-3 PUFA and n-6 PUFA can substitute for each in membrane lipids to some extent. Membrane fatty acid composition appears to be regulated and specific for different species. The role of essential fats in the diet of animals on (1) basal metabolic rate, (2) thermoregulation, (3) maximum longevity, and (4) exercise performance is discussed.


2008 ◽  
Vol 56 (5) ◽  
pp. 1654-1660 ◽  
Author(s):  
Mamun M. Or-Rashid ◽  
Nicholas E. Odongo ◽  
Bhishma Subedi ◽  
Pralhad Karki ◽  
Brian W. McBride

1993 ◽  
Vol 71 (9) ◽  
pp. 684-689 ◽  
Author(s):  
B. E. March

This paper emphasizes those aspects of fatty acid research in fish that have relevance to the investigation of the functions of essential fatty acids in other species. Lipid requirements of fish came under investigation only in the 1960s. The most significant finding has been the requirement for n − 3 fatty acids. The dietary ratio of (n − 3):(n − 6) is critical if the essential requirement is met by C18 fatty acids because of competition between fatty acids for the enzymes involved in elongation and desaturation to produce the physiologically essential long-chain fatty acids. The fatty acid composition of fish lipids varies according to the fatty acid profile of the dietary lipid. The fatty acid composition of fish also responds to temperature changes in an adaptive mechanism for maintenance of membrane homeoviscosity and physiological function over a range of temperatures. The dietary intake of essential fatty acids by brood stock must be adequate for ova formation and for embryonic development, with the latter requirement being more critical for reproductive success. Absolute requirements of fish for essential fatty acids are difficult to define and may vary depending upon the dietary ratio of (n − 3) to (n − 6) fatty acids.Key words: essential fatty acids, nutritive requirements, fish.


1980 ◽  
Vol 44 (1) ◽  
pp. 47-52 ◽  
Author(s):  
E. Payne ◽  
P. V. Rattray

1. The fatty acid composition of milk fat of Coopworth sheep offered varying pasture allowances has been determined after 1, 14 and 35 d of lactation. Differences in fatty acids occurred, particularly between 1 and 14 d, with a major increase in C18:0 whilst C16:0, C14:0 and C18:3 showed decreases.2. When pasture allowances were restricted there were decreases in the short-chain fatty acids from C6 to C14 and an increase in C18:1 as has been observed previously for cattle. The C18:1:C10 value is a convenient measure of these changes and can be determined more rapidly than determining all the lower fatty acids.3. The increased demand for milk resulting from suckling twin lambs caused an increase in C18:1 and decreases in C10 and C12 due to an increased utilization of body reserves.4. The level of linoleic acid was much greater than has been previously observed in sheep given hay and contributes to the rapid rise in linoleic acid levels in lambs born under grazing conditions.


Sign in / Sign up

Export Citation Format

Share Document