n-3 enrichment of chicken meat. 2. Use of precursors of long-chain polyunsaturated fatty acids: Linseed oil

To assess the effect of supplying linseed oil (LO) in the diet on performan ce, fatty acid (FA) composition, and quality objective parameters of broile r meat, diets enriched with 0, 2, or 4% LO plus tallow (T) up to 8% added f at (T1, T2, and T3, respectively) were given to broiler chickens throughout a 38-d growth period. T3 birds were slaughtered at 24 or at 52 d of age to study the effect of feeding time on FA accumulation in tissue. Objective a nd subjective evaluations of meat quality were performed on samples from 38 -d-old birds, and the FA profiles of thigh and liver samples were determine d. Performance parameters showed little difference between treatments. The differences in carcass yield values or in the objective quality parameters of the meat between treatments were not significant. Increased levels of LO clearly decreased the saturated (SAT) and monounsaturated FA (MUFA) conten ts. LO increased the amount of polyunsaturated FA (PUFA), mainly because of the linolenic (LNA) and linoleic (LA) acid content in the T3 samples, but they hardly reflected the wide range given in the experimental diets. The n -3 long-chain (LC) PUFA content of T3 thighs was slightly higher than in T1 thighs. Unexpectedly, longer feeding time of LO diets did not result in pe ripheral tissue accumulation of n-3 LC-PUFA, although chickens could conver t LNA to longer-chain metabolites in liver at 24 d of age.