Agriculture Reference
In-Depth Information
cytokine production while n-6 FA is shown to be pro-inflammatory (Calder, 2003, 2013).
As shown in Figure 16.1, LA can be converted to ARA, and ALA can be converted to
EPA. ARA, which is the precursor for 2 series of PGE and thromboxanes as well as
the 4 series of leukotrienes, and EPA, which is the precursor for 3 series of PGE and
thromboxanes as well as the 5 series of leukotrienes, can also be converted to their
respective eicosanoids, which play an important role in atherosclerosis, coronary heart
disease, bronchial asthma, and other inflammatory conditions. The PGE of the 2 series
regulate the production of pro-inflammatory cytokines, whereas the PGE of the 3 series
are anti-inflammatory eicosanoids. To encourage the production of anti-inflammatory
PGE and to discourage the production of inflammatory PGE, ARA should be reduced in
the diet, and an appropriate amount of n-3 FA should be consumed (Rossi
et al.
, 2010).
Neonatal survival is dependent on sufficient colostrum ingestion for humoral immune
protection (Rooke and Bland, 2002). Dietary provision of long-chain n-3 PUFA to piglets
modulates both the intensity and the duration of inflammatory immune responses
(Leonard
et al.
, 2011). The anti-inflammatory effect has been shown in piglets suckling
sows fed fish oil; the substitution of lard with menhaden fish oil (70%g/kg feed) in late
gestation and lactation diets reduced
in vitro
eicosanoid release by immune cells of nursing
piglets (Fritsche
et al.
, 1993). Omega-3 FA from fish oil has been shown to improve
the development of the brain and immunity of neonatal piglets (Leskanich and Noble,
1999). Bazinet
et al.
(2004) reported that a high intake of ALA from flaxseed oil (3.5%)
by piglets until 57 d of age modulated their immune function and tissue FA response to
antigens with an adjuvant. In addition, n-3 FA and their metabolites are natural ligands
for peroxisome proliferator receptor activator gamma (PPARγ). This PPARγ plays a
fundamental role in the immune response through its ability to inhibit the expression of
inflammatory cytokines and to direct the differentiation of immune cells towards anti-
inflammatory phenotypes (Rossi
et al.
, 2010). It has been reported that n-3 PUFA not
only reduced the secretion of the pro-inflammatory cytokines tumour necrosis factor-α
(TNF-α) and interleukin 6 and 8, but also enhanced the expression of PPARγ (Calder,
2013). However, it has been suggested that a high intake of n-6 FA, especially ARA,
can contribute to inflammatory processes and predispose to or exacerbate inflammatory
diseases (Papadopoulos
et al.
, 2009). Rooke and Bland (2002) reported that the synthesis
of immunoglobulin of class G (IgG) by piglets is positively correlated to the amount
of maternal IgG absorbed, thus reinforcing the importance of an adequate IgG intake
from colostrum. Mitre
et al.
(2005) demonstrated that shark-liver oil supplementation
from d 80 of gestation to weaning increased colostral IgG concentrations of sows, and
subsequently serum IgG concentrations in suckling piglets. Mateo
et al.
(2009) observed
an increased concentration of colostral IgG when supplementing long chain n-3 FA,
obtained from fish oil, in sows' diets (Figure 16.2). Farmer
et al.
(2010) also observed an
enhanced immune response of piglets when sows were fed flaxseed meals during late-
pregnancy and lactation, which may have induced the increased survival rate of piglets.
However, maternal fish oil supplementation from d 109 of gestation until weaning up-
regulated intestinal pro-inflammatory cytokine expression and failed to influence the
immunoglobulin composition of mammary secretions (Leonard
et al.
, 2010b, 2011).
