Unknown,Transcriptomics,Genomics,Proteomics

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Identifying gene expression differences induced by diets that lead to higher omega-3 fatty acid deposition in beef cows

ABSTRACT: The objective of this project is identifying differentially expressed (DE) genes which are associated with higher omega-3 fatty acids deposition in beef cows. Omega-3 fatty acids have been found to influence meat flavor and are beneficial to human health. Supplementation of livestock diets with flaxseed, a rich source of ë±-linolenic acid, is the most common means of producing omega-3 fatty acid-enriched animal products. Towards the goal of enhancing beef fatty acid composition, 64 crossbred cull cows (~30 months of age) with similar breed composition were randomized by weight/body condition, and fed one of four 50:50 forage:concentrate diets on a DM basis (16 cows/treatment), containing ground barley grain with either hay or silage, supplemented with 0 or 15% ground flaxseed (DM basis). Cows were slaughtered after spending 140 days on the treatment diets. Five cows from each of the four diets were selected for transcriptional analysis based on FA profiles of the kidney fat collected at slaughter. RNA was isolated from Longissimus thoracis muscle, subcutaneous and kidney fat of each cow (20 samples/tissue) and hybridized in duplicate to BOMC 24K 60-mer microarrays. Differential gene expression between flax-fed and non-flax-fed cows as well as identifying those genes associated with fatty acid metabolism were studied.

ORGANISM(S): Bos taurus

SUBMITTER: Aidin Foroutan

PROVIDER: E-MTAB-3371 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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