Abstract. The fatty acid (FA) composition in the intramuscular fat (IMF) of the musculus
longissimus dorsi (MLD) of Ile de France purebred lambs in two different
production systems in Slovakia was evaluated using gas chromatography. In the first production system,
lambs and ewes were assigned to pasture without access to concentrates (P).
In the second system, lambs and ewes were confined indoors with hay/silage and
access to concentrates (S). An analysis of variance with the following factors was employed: production
system, sex, and production system–sex interactions. The
proportions of arachidonic, eicosapentaeonic, docosapentaeonic, and
docosahexaenoic FAs, i.e. long-chain polyunsaturated FA (PUFA), were
significantly higher in P lambs (1.83, 0.82, 0.92, 0.29 g 100 g−1
FAME, respectively) than in S lambs (0.45, 0.14, 0.30, 0.09 g 100 g−1 FAME, respectively). The
proportions of conjugated linoleic acid (CLA), n-6 PUFA, n-3 PUFA, and
essential FA (linoleic and α-linolenic) were also significantly
higher in P lambs (2.10, 8.50, 4.55, and 8.80 g 100 g−1 FAME, respectively) than in
S lambs (0.65, 3.27, 1.50, and 3.64 g 100 g−1 FAME, respectively). The proportions
of palmitic acid and myristic acid as important individual saturated FAs (SFA)
were significantly higher in S lambs (28.51 and 8.30 g 100 g−1 FAME, respectively)
than in P lambs (21.80 and 5.63 g 100 g−1 FAME, respectively). The proportion of
all SFAs was also significantly higher in S lambs (57.87 g 100 g−1
FAME) than in P lambs (48.70 g 100 g−1 FAME). From a nutrition and
human health point of view (i.e. higher proportions of PUFA, CLA, and
essential FAs and lower proportions of SFAs), meat from P lambs was found to be more
favourable and would be more highly recommended for consumption.
Psychosocial stress and cortisol stress reactivity predict breast milk composition
