The fatty acid (FA) composition of the experimental diets is shown in Table 1. On a general basis, when expressed as % DM, all FA increased progressively with the increase of dietary lipid content. The poly-unsaturated FA (PUFA) of the n-3 series ranged from 1.91% DM (diet L6) to 6.70% DM (diet L25), whereas the n-6 PUFA ranged from 0.48% DM (diet L6) to 5.17% DM (diet L25). Similarly, the EPA plus DHA content varied from 1.57% DM (diet L6) to 4.95% DM (diet L25), whereas the DHA/EPA ratio remained relatively constant (2.13–2.27%). In relative terms, as % of total FA, the polyenes slightly increased with the increase of the dietary lipid content, with the subsequent decrease of the monoenes fraction. The n-3 and n-6 PUFA were slightly higher in diet L25, whereas the ratio DHA/EPA varied among 1.79% (diet L6), 2.12% (diet L10) and 2.17% (diet L25).