The fatty acid profile of muscle and adipose tissue of lambs fed camelina or linseed as oil or seeds

Abstract

The objective of this study was to evaluate the impact of diets enriched with plant oils or seeds, high in polyunsaturated fatty acids (PUFA), on the fatty acid profile of sheep intramuscular and subcutaneous adipose tissue (SAT). Sixty-six lambs were blocked according to initial body weight and randomly assigned to six concentrate-based rations containing 60 g fat/kg dry matter from different sources: (1) Megalac (MG; ruminally protected saturated fat), (2) camelina oil (CO), (3) linseed oil (LO), (4) NaOH-treated camelina seed (CS), (5) NaOH-treated linseed (LS) or (6) CO protected from ruminal saturation by reaction with ethanolamine; camelina oil amides (CA). The animals were offered the experimental diets for 100 days, after which samples of m. longissimus dorsi and SAT were collected and the fatty acid profile determined by GLC. The data were analyzed using ANOVA with 'a priori' contrasts including camelina v. linseed, oil v. NaOH-treated seeds and CS v. CA. Average daily gain and total fatty acids in intramuscular adipose tissue were similar across treatments. The NaOH-treatment of seeds was more effective in enhancing cis-9, trans-11 conjugated linoleic acid (CLA) incorporation than the corresponding oil, but the latter resulted in a higher content of trans-11 18:1 in both muscle neutral and polar lipids ( P , 0.01, P , 0.001, respectively). Inclusion of LS resulted in the highest PUFA : saturated fatty acid (SFA) ratio in total intramuscular fat (0.22). The NaOH-treatment of seeds resulted in a higher PUFA/SFA ratio (0.21 v. 0.18, P , 0.001) than oils and on average, linseed resulted in a higher PUFA/SFA ratio than camelina ( P , 0.01). Lambs offered LS had the highest concentration of n-3 PUFA in the muscle, while those offered MG had the lowest ( P , 0.001). This was reflected in the lowest ( P , 0.001) n-6: n-3 PUFA ratio for LS-fed lambs (1.15) than any other treatment, which ranged from 2.14 to 1.72, and the control (5.28). The trends found in intramuscular fat were confirmed by the data for SAT. This study demonstrated the potential advantage from a human nutrition perspective of feeding NaOH-treated seeds rich in PUFA when compared to the corresponding oil. The use of camelina amides achieved a greater degree of protection of dietary PUFA, but decreased the incorporation of biohydrogenation intermediates such as cis-9, trans-11 CLA and trans-11 18:1 compared to NaOH-treated seeds.

The use of stoned olive cake and rolled linseed in the diet of intensively reared lambs: effect on the intramuscular fatty-acid composition

“…According to this pattern, the inclusion of linseed in the diet resulted in an increase in t11-18:1, which, in turn, led to an increase in CLA content in the intramuscular fat, especially in the neutral lipids. Similar results have been previously obtained by feeding lambs diets supplemented with linseed oil (Noci et al, 2011). The CLA and t11-18:1 are considered potential bioactive compounds for human health (Mele and Banni, 2010) and the use of linseed in the diet of lambs may be a feasible strategy to enrich meat with these fatty acids.…”

“…Two isomers (t4-and t5-18:1) were detected only in neutral lipids. The higher affinity of trans fatty acids for neutral lipids was previously reported, especially when the lambs were fed a diet enriched with 18:3 n-3 (Jerónimo et al, 2011;Noci et al, 2011). According to the pattern of trans-18:1, the biohydrogenation of dietary c9-18:1 contained in the O and OL diets resulted in an accumulation of t5-18:1 t6-8-18:1, t9-18:1, t10-18:1 and t12-18:1, whereas the content of t11-18:1 did not significantly vary when compared with C treatment.…”

“…However, the lack of negative effects on the growing performance suggested that the stoning process could have improved the digestibility of the diet as already observed by Sadeghi et al (2009), using experimental diets containing 20% of stoned olive cake. The dietary treatment did not affect slaughtering performance according to previous studies that included comparable amounts of stoned olive cake or vegetable fat in the diet of finishing lambs (Mioc et al, 2007;Berthelot et al, 2010;Noci et al, 2011).…”

“…Therefore, the content of total fatty acids and the proportion between polar and neutral fatty acids did not differ between treatments (Tables 3 to 5). This result allowed to avoid confounding effects of total fatness on meat fatty-acid composition (Noci et al, 2011). Therefore, differences in fatty-acid composition were mainly because of the diet and the selectivity of individual fatty acids for polar and neutral lipids.…”

Effect of linseed supplementation of the gestation and lactation diets of dairy ewes on the growth performance and the intramuscular fatty acid composition of their lambs

“…Some authors found an increase of LC-PUFAn-3 in lambs fed linseed diets (Noci et al, 2011;Berthelot et al, 2012), while others did not observe any effect (Bas et al, 2007). Others found that feeding ewes a n-3-enriched diet in lactation increased the proportion of 18:3n-3 and their longer chain derivatives in suckling lamb muscles (Gómez-Cortés et al, 2014;Mele et al, 2014), whereas Berthelot et al (2012) did not report such effects in their earlier experiment.…”