S. Lopez-ferrer et al., n-3 enrichment of chicken meat using fish oil: Alternative substitution with rapeseed and linseed oils, POULTRY SCI, 78(3), 1999, pp. 356-365
Two sequential experiments were conducted to assess the effect of replacing
a fish oil diet with vegetable oil diets on broiler chicken performance an
d fatty acid (FA) composition and sensory traits of broiler meat. A diet en
riched with 8.2% fish oil (FO) was fed to the birds throughout the 5-wk gro
wth period (T1), the same basal diet being supplemented with 8.2% Linseed o
il (LO, Experiment 1) or rapeseed oil (RO, Experiment 2) in three different
periods: the last week before slaughtering at 35 d (T2), the last 2 wk (T3
), and throughout the experiment (T4). A sensory evaluation of the meat was
carried out and its FA profile was determined. Performance parameters were
not significantly different among treatments. Removing FO resulted in lowe
r values of saturated and higher n-6 FA content, the latter because of the
increase in Linoleic acid in both experiments. The amounts of long-chain n-
3 polyunsaturated fatty acids (PUFA) were significantly depressed when FO w
as replaced. However, replacing FO by LO resulted in minimal effects on tot
al n-3 FA, due to the increase in Linolenic acid. The substitution of EO by
RO resulted in a decrease in the n-3 FA content, whereas levels of monouns
aturated FA (MUFA) increased in direct relation to the larger amounts of ol
eic acid in the diet. Sensory panelists scored as unacceptable those meats
from T1 in both experiments. Replacing 1 (T2) or 2 (T3) wk FO wi th vegetab
le oil clearly resulted in the improved sensory quality of meat.