n – 3 Docosapentaenoic acid in blubber of dam and pup grey seals (Halichoerus grypus): implications in the Inuit diet and for human health

Abstract

ACKMAN, R. G., and EATON, C. A. 1988. n -3 Docosapentaenoic acid in blubber of dam and pup grey seals (Halichoerus grypus): implications in the Inuit diet and for human health. Can. J. Zool. 66: 24.28-243 1. n-3 Docosapentaenoic acid (22:5n -3) is shown to constitute as much as 6 % of the total fatty acids in six sets of dam-pup blubber samples from grey seals, Halichoerus grypus. Relative to fish oils, this fatty acid is several times more plentiful in the seal fats that form an important part of Inuit diets. Consideration of intakes of a-3 fatty acids as therapeutic agents for cardiovascular and other health disorders in man should include this quantitatively important fatty acid of seal fats. ACKMAN, R. G., et EATON, C. A. 1988. n -3 Docosapentaenoic acid in blubber of dam and pup grey seals (Halichoerus grypus): implications in the Inuit diet and for human health. Can. J. Zool. 66 : 2428-2431. L'acide n-3 docosapentaenoi'que (22:5n -3) constitute au moins 6 % du contenu total en acides gras dans six series d'echantillons de lard de mkres -petits chez le Phoque gris (Halichoerus grypus). Cet acide est beaucoup plus abondant dans les graisses des phoques, qui constituent une fraction importante du regime alimentaire des Inuits, que dans les huiles des poissons. Si les acides gras a-3 peuvent effectivement servir d'agents therapeutiques dans les cas de maladies cardio-vasculaires ou autres chez l'homme, il faudrait songer a inclure, parmi ces agents, cet acide gras trks abondant des graisses du phoque.[Traduit par la revue] IntroductionMaterials and methods The current interest in EPA (eicosapentaenoic acid; 20:5n -3) and DHA (docosahexaenoic acid; 22:6n -3) in human nutrition arose from observations on the diets of Greenland Inuit (Bang and Dyerberg 1976) in which seal blubber was shown to be an important component. Later EPA was singled out as a fatty acid with unique and possibly highly desirable therapeutic benefits in human cardiovascular problems (Dyerberg et al. 1978). Recently von Schacky and Weber (1985) have also indicated that DPA (the n -3 isomer of docosapentaenoic acid; 22:5n-3) is an intermediate between EPA and DHA, which is active in man.In our opinion the remarkably high proportion of DPA in seal fats has not received the attention it deserves. Mention was included in a survey of Nova Scotia commercial seal oils produced largely from young harp seals, Pagophilus groenlandica (Ackman et al. 1971), and in other papers on North Atlantic seal fats (Jangaard and Ke 1968;Ackman et al. 1972;Ackman and Hooper 1974), extending our observations to a few Atlantic harbour (Phoca vitulina vitulina) and grey (Halichoerus grypus) seals.The role of DPA in human health may become more important as efforts are made to compare the epidemiological data for Inuit health with the absence of specific diseases (Simopoulos et al. 1986) and thus to suggest therapeutic doses with fish oil or fish oil concentrates. In the latter oils, DPA is a relatively minor component, usually 1 -2 % of total fatty acids in natural f...

The lipid composition of selected tissues from a Mediterranean monk seal,Monachus monachus

“…The lipid contents of blubber, heart and liver of the individual monk seal examined here are all consistent with those reported previously for other species of seal (5,6), and the high lipid content of the brain is typical of brain tissue of mammals in general (17). With the exception of the brain, all the tissues of the monk seal contained significant amounts of free fatty acids in their total lipid.…”

“…The data presented in this study were obtained on only one monk seal, and, consequently, caution must be ap- Table 2. plied when extrapolating the patterns of lipid composition to this species in general. The results, however, do allow a representative comparison of the lipid compositions of different tissues within an individual monk seal, a subject for which comparative data are surprisingly rare as previous studies of seal lipids have concentrated on blubber (5,6,12).…”

“…Although data exist concerning the biology, behavior and feeding habits of the Mediterranean monk seal (4), the lipid composition of its tissues has not been reported previously. In contrast, a substantial amount of information is available concerning the fatty acid composition of commercial oils, as well as tissue and milk lipids from several species of seals from Arctic and temperate waters (5)(6)(7)(8)(9)(10)(11)(12). Most previous studies of seal lipids have concentrated on the total lipids from blubber, while the lipid composition of other tissues has not been examined in detail.…”

Use of blubber fatty acid profiles to detect inter-annual variations in the diet of grey seals Halichoerus grypus

“…These major characteristics and overall pattern are basically similar to those in other reports for grey seal blubber (Ackman & Hooper 1974, Ackman & Eaton 1988, Schweigert et al 1990, GrahlNielsen & Mjaavatten 1991, Fredheim et al 1995.…”

Fatty acids in plasma of California sea lion pups (Zalophus c. californianus) from Los Islotes, Baja California Sur, Mexico

“…Due to the commercial interest on the oils of marine origin because of its importance for the human health, most of the studies about fatty acids in marine mammals have been done in the milk, in the fat layer and in the oils from the subcutaneous fat layer and/or in some organs such as the kidney, the liver and the heart (Ackman, 1988;1994;Ackman and Eaton, 1988;Conquer et al, 1999;Deutch et al, 2000;Guitart et al, 1999;Grompone et al, 1990;Ochoa-Acuña et al, 1999;Yurkows, 1987). To date, there are not any backgrounds about the lipidic composition of the California sea lion's plasma despite the importance of fat in these animals.…”