Abstract

Swedish lambs often undergo a short-term intensive feeding period prior to slaughter. Composition of the diet and feeding duration will influence the fatty acid composition of the product. To investigate such influences, ram lambs (n=34) were reared by ewes fed silage (S) or silage + concentrates (barley/peas/rape cake) (C) during lactation. Following weaning on average at 65d, half of the lambs remained on their initial diet (groups CC and SS), while the other half were subjected to a cross-over diet (groups CS and SC) to monitor how a post-weaning diet change would affect the fatty acid profile of the tissue. Post-weaning diets included ad lib silage or ad lib silage + concentrates 37d. Lambs were slaughtered at about 102d with a live weight of 38.3kg (±4.5kg). In M. semispinalis capitus , concentrates increased the 18:2n-6 (linoleic acid, LA), while silage increased the 18:3n-3 (linolenic acid, ALA) proportion. The n-6/n-3 ratio decreased with duration of concentrate feeding; CC>CS>SC>SS. Results indicate that the lambs’ muscle fatty acid profile was more heavily influenced by the pre-weaning diet. Muscle n-3 PUFA increased with duration of silage feeding, being 4.7 (SS), 3.6 (SC), 3.2 (CS) and 2.7 (CC) for the feeding groups. Fatty acid profile of the ewes’ milk shows that silage increased 16:0 and concentrates increased 18:0 levels. Milk composition reacted to the diets similar to the lambs; concentrates increased LA proportion and silage increased ALA proportion. Total n-3 PUFA in milk increased with silage, compared to silage: concentrate feeding, being 2.3 and 1.6 %, respectively. In addition, the long chain n-3 PUFA (20:5n-3, EPA and 22:5n-3, DPA) increased. We conclude that the fatty acid profile of lambs muscle finished within five weeks will be most affected by the milk fatty acid profile. Additionally, introduction of concentrates at any stage of the lamb finishing period will have a negative influence on the n-3 PUFA level of the lamb tissue

Published in

Conference

6th Euro Fed Lipid Congress

SLU Authors

• Turner, Tyler

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    

• Bernes, Gun

  • Department of Agricultural Research for Northern Sweden, Swedish University of Agricultural Sciences
    

• Pickova, Jana

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Food Science
Animal and Dairy Science
Veterinary Science


Permanent link to this page (URI)

https://res.slu.se/id/publ/21085