Agriculture Reference
In-Depth Information
Table 16.1. Contents of n-3 and n-6 fatty acids (%) in different types of vegetable or fish oils.
Item
C18:2n-6 (LA)
C18:3n-3 (ALA)
C20:5n-3 (EPA)
C22-6n-3 (DHA)
Vegetable oils
1
Linseed oil
15.18
54.24
-
-
Canola oil
20.12
8.37
-
-
Soybean oil
56.02
7.15
-
-
Corn oil
59.27
1.07
-
-
Sunflower oil
71.17
0.45
-
-
Walnut oil
2
51.60
17.82
-
-
Fish oils
3
Menhaden oil
2.7
1.3
12.5
8.9
Sardine oil
2.5
1.3
9.6
8.5
Salmon oil
2.0
1.0
6.7
16.1
Shark-liver oil
2.3
0.4
9.2
7.3
Tuna oil
0.9
0.4
4.4
22.2
1
Adapted from Zambiazi
et al.
(2007).
2
Adapted from Dogan and Akgul (2005).
3
Adapted from Gruger (1967).
16.3.2
Polyunsaturated fatty acids biomagnification
During the last stage of intrauterine life, there is a gradual increase in the transfer of FA from
the mother to the fetus, as demonstrated by the similarity of the FA profile in the tissues
of piglets and of the sow diet (Farmer and Petit, 2009). In humans, with increasing age of
gestation, there is an increase in the concentration of PUFA in the blood of the umbilical
cord. his is a process known as 'biomagniication, i.e. an increase in the concentration
and transfer of EFA to the foetal circulation, umbilical cord, liver and brain, which reaches
its maximum level in the last stages of pregnancy (Uauy and Dangour, 2006). According
to Lauridsen and Jensen (2007), the FA profile of plasma and tissues of piglets is highly
influenced by the FA composition of the diet of the mother up to 3 wks after weaning.
Polyunsaturated n-3 FA have a key role in many physiological activities such as the
development of the central nervous system, retinal function, fluidity of cell membranes,
prostaglandin synthesis, and immunity (Innis, 2007; Kim
et al.
, 2007; Mateo
et al.
, 2009;
Uauy and Dangour, 2006). In particular, DHA is the major component of the nervous
system and cell membranes and exerts an important influence on the membrane stability
and on functional properties of membrane proteins (dopamine and neurotransmitters).
16.3.3
Effects of omega fatty acids on immune status of sows and piglets
It has been reported that the n-3 and n-6 FA are stored in cell membranes as structural
components and also as substrates for the production of eicosanoids, such as
prostaglandins (PGE) (Rossi
et al.
, 2010). Omega-3 (n-3) FA can decrease inflammatory
