In general the fatty acid profile of plasma and immune tissues reflects the fatty acid composition of the diet. Like this, meat fatty acid composition in poultry can be changed via the dietary fatty acids (Lopez-Ferrer et al. 2001). The degree of unsaturation of the lipid source used during dietary manipulation also has a significant positive effect on production performance and carcass composition (Crespo & Esteve-Garcia, 2001; Villaverde et al., 2004). The LA, ALA and long-chain PUFA content responds quickly to raised dietary concentrations. In poultry, dietary FAs are absorbed unchanged from the intestine and incorporated into tissue lipids. The PUFA, like LA and ALA cannot be synthesized and tissue concentrations respond rapidly to dietary changes.  Modulation of fatty acid profiles as a result of n-3 PUFA supplementation or dietary modification is well documented in chickens (Fritsche et al., 1991b; Lopez-Ferrer et al., 1999; Lopez-Ferrer et al., 2001a; Bou et al., 2004; Puthpongsiriporn and Scheideler, 2005; Kartikasari et al., 2010), and humans (Meydani et al., 1991; Kew et al., 2004; Miles et al., 2004).

A more effective way to increase tissue concentrations of n-3 PUFA is to supplement the diet with fish oils (FO) which are good sources of these fatty acids. Several studies in the literature demonstrate that chickens fed marine oils accumulate significant amounts of n-3 PUFA in their eggs and meat. Bou et al. (2004) reported that supplementing broiler diets with 25 g/kg of FO doubled the amount of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids in their meat compared with that from chickens fed diets supplied with 12.5 g/kg of FO (0.06 vs. 1.00 and 0.09 vs. 1.38 for EPA and DHA, respectively). Supplementing broiler chickens with 4% FO decreased the proportions of saturated (from 43.77 to 39.84% of total fatty acids) and MUFA (from 41.26 to 37.60% of total fatty acids) and increased the proportion of n-3 PUFA (from 2.09 to 8.14% of total fatty acids) in thigh samples (Lopez-Ferrer et al., 2001b). Lopez-Ferrer et al. (1999) substituted 82 g/ kg of FO in a supplemented broiler diet with the same amount of linseed and rapeseed and concluded that the total amount of n-3 PUFA in the chicken meat decreased when FO was removed from the diet, whereas the proportions of n-6 PUFA and MUFA (in the form of oleic acid) increased. Febel et al., (2008) reported that FA composition in tissues reflected the FA pattern of the diets, although proportion of FAs with four or more double bonds was metabolic specific. Linseed oil diet increased the level of C18:3, C20:5 and C22:6 in tissue lipids in relation to lard, sunflower oil, and soybean oil diets. In fish oil fed boilers, as n-3 fatty acid concentrations in muscle increased, those of n-6 declined and saturated fatty acid concentrations remained unchanged, showing the competition which exists between n-6 and n-3 fatty acids for inclusion into lipid molecules.

Different studies have focused on the role of fatty acids in meat flavour formation, as thermal lipid degradation is a major contributor to aroma volatiles (Mottram, 1991). Cameron & Enser (1991) demonstrated that eating quality traits (tenderness, juiciness, flavour and overall acceptability) of pork were generally improved as the concentration of MUFA (oleic acid) increased and PUFA (LA) decreased. It was further noted that sensory quality may be adversely influenced by supplementation with fish oil or other n-3 PUFA sources such as linseed (Gonzalez-Esquerra & Leeson, 2000a and b; Surai & Sparks, 2001). Despite this the perception of fishy off-odour changes from one country to another, showing in some cases contradictory results (Azcona et al., 2008). A significant differences with 1.5% fish oil or linseed diet supplementation was reported by Surai and Sparks (2001), whereas, Lopez-Ferrer et al., (2001) did not find significant differences up to 4% fish oil supplementation. Similarly, Hugo et al., (2009) reported that it could be possible to manipulate sensory characteristics of broiler breast meat according to consumer preferences by the inclusion of omega-9 (high oleic sunflower oil) or omega-3 (fish oil) in poultry diets. However, inclusion of high oleic sunflower oil resulted in most liked, while fish oil inclusion produced the least preferred meat, irrespective of dietary inclusion level. This clearly indicates the differences in sensory perceptions of respondents in different studies.