Chinyere Ekine-Dzivenu (PhD Candidate) Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Canada. 1

Background Objectives Materials and methods Results and discussion Conclusion Acknowledgement 2

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SFA Increased Plasma cholesterol - Cardiovascular diseases - Cancer - Obesity MUFA & PUFA Reduced plasma cholesterol CLA Anti-carcinogenic, anti-atherosclerotic Anti-diabetic Anti-Obesity Type of dietary fat (fatty acid profile) matters more than the amount of fat. 4

Improving beef fatty acid composition Nutrition approach –Added cost –Change not permanent –May affect flavor Traditional genetic improvement approach –Permanent and accumulative change BUT difficult/expensive to measure and measured after slaughter Genomics –Marker assisted selection/genomic selection 5

Estimate heritability of fatty acids in beef brisket adipose tissue, subcutaneous adipose tissue and longissimus luborum muscle to assess the potential for genetic improvement Discover SNP markers associated with FA profile in beef for marker assisted selection or marker based diet management Estimate phenotypic and genetic correlation between FAs within each tissue in order to prevent antagonism when genetic selection is made

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Phenotype Genotype Over 80 FA in the brisket adipose on 223 beef steers Over 80 FA in the subcutaneous adipose and longissimus luborum muscle on 1366 animals Heritability and correlations estimated using univariate and bivariate animal model implemented in ASreml after accounting for fixed effects. 961 polymorphic markers for Bayesian candidate gene association study on adjusted data 8

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% FAME B.Adipose % FAME S.Adipose % FAME Muscle Fig1. Variation among individual animals for different fatty acids Each dot represents an individual animal 10

Longissimus Luborum Muscle (n=1366) Subcutaneous Adipose (n=1366) Brisket Adipose (n=223) Fatty AcidsMeanh 2 ±SEMeanh 2 ±SEMeanh 2 ±SE 14: ± ± ± : ± ± ± : ± ± ± : ± ± ± : ± ± ± c-14: ± ± ± c-16: ± ± ± c-17: ± ± ± 0.1 9c-18: ± ± ± t-18: ± ± ± c-18: ± ± ± t-18: ± ± ± c-18: ± ± ± :2n ± ± ± 0.13 Sumtrans18: ± ± ± 0.11 SumCLA ± ± ± 0.1 SFA ± ± ± 0.11 MUFA ± ± ± 0.1 PUFA ± ± ± 0.12 BFA ± ± ± 0.1 SFA+BFA ± ± ± 0.11 n ± ± ± 0.13 n-6/n ± ± ± 0.1 Health Index ± ± ± 0.12 Health Index = ΣMUFA +ΣPUFA 4X14:0+16:0 High Moderate Low Table 1. Heritability of selected fatty acids in 3 beef tissues 11

TraitSFAMUFAPUFASumCLAHealth_Index SFA-0.99±0-0.31± ± ±0.01 MUFA-0.99± ± ± ±0.01 PUFA-0.41± ± ± ±0.06 sumCLA-0.29± ± ± ±0.06 Health Index-0.99± ± ± ±0.44 Table 2. Phenotypic (above diagonal) and genetic (below diagonal) correlation between selected fatty acid groups in beef tissues TraitSFAMUFAPUFASumCLAHealth Index SFA-0.59± ± ± ±0.02 MUFA-0.77± ± ± ±0.08 PUFA-0.18± ± ± ±0.1 sumCLA-0.02± ± ± ±0.11 Health Index-0.89± ± ± ±0.19 Brisket adipose Subcutaneous adipose Longissimus Luborum TraitSFAMUFAPUFASumCLAHealth Index SFA-0.98±00.05± ± ±0.03 MUFA-0.98± ± ± ±0.03 PUFA-0.15± ± ± ±0.11 sumCLA-0.56± ± ± ±0.1 Health Index-0.84± ± ± ±

Fig.2. Schematic overview of associations of fatty acids with SNPs in candidate genes. Allele substitution effect indicated by color key 13

Receptors SCD PNPLA2 LPL F5 CPT2 ACADL BDH1 ATIC Transporter SLC27A2 ATP2B1 AP2B1 Transcription Regulator NR1H3 RUNX1T1 IRF2 BRCA1 ANKRD1 CRHR1 RARA TRHR EIF3H Enzyme Translation Regulator Fig 3. Variation in FA among individuals as a result of variation in different cellular processes 14

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Variation exists in the amount of each fatty acid in beef tissues. Individual animals vary in the amount of each FA deposited in tissues. Each fatty acid in beef is a complex trait (influenced by several genes). Identified markers throw light on processes that can cause variation in FA between animals. Results show possibility of selecting beef with superior genetics to improve not only beneficial FA content but also eating quality of beef. Results show possibility of simultaneously improving beneficial FA in the adipose. Attention should be paid to the moderate negative correlation between muscle MUFA and PUFA. 16

Use a higher density SNP panel (bovine 50K SNP chip) to capture more markers explaining a significant amount of variation for beneficial fatty acids among individual animals. Phenotypic and genetic correlation of fatty acids in the subcutaneous adipose tissue and longissimus luborum muscle with carcass and meat quality traits 17

Supervisor: Dr. Changxi Li Group members, co-investigators and committee Liuhong ChenMichael Dugan Michael VinskyJennifer Aalhus John BasarabNoelia Aldai Paul StothardTim McAllister Fiona BuchananCarolyn Fitzsimmons Erasmus OkineZhiquan Wang Funding: 18

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