Genetic Variation in FABP4 and Evaluation of Its Effects on Beef Cattle Fat Content.

FABP4 is a protein primarily expressed in adipocytes and macrophages that plays a key role in fatty acid trafficking and lipid hydrolysis. FABP4 gene polymorphisms have been associated with meat quality traits in cattle, mostly in Asian breeds under feedlot conditions. The objectives of this work were to characterize FABP4 genetic variation in several worldwide cattle breeds and evaluate possible genotype effects on fat content in a pasture-fed crossbred (Angus-Hereford-Limousin) population.

Genetic characterisation of PPARG, CEBPA and RXRA, and their influence on meat quality traits in cattle.

Background: Peroxisome proliferator-activated receptor gamma (PPARG), CCAAT/enhancer binding protein alpha (CEBPA) and retinoid X receptor alpha (RXRA) are nuclear transcription factors that play important roles in regulation of adipogenesis and fat deposition. The objectives of this study were to characterise the variability of these three candidate genes in a mixed sample panel composed of several cattle breeds with different meat quality, validate single nucleotide polymorphisms (SNPs) in a local crossbred population (Angus - Hereford - Limousin) and evaluate their effects on meat quality traits (backfat thickness, intramuscular fat content and fatty acid composition), supporting the association tests with bioinformatic predictive studies.

Results: Globally, nine SNPs were detected in the PPARG and CEBPA genes within our mixed panel, including a novel SNP in the latter.

Characterization of the bovine gene LIPE and possible influence on fatty acid composition of meat.

LIPE is an intracellular neutral lipase, which is capable of hydrolyzing a variety of esters and plays a key role in the mobilization of fatty acids from diacylglycerols. The objectives of this study were to characterize the genetic polymorphism of bovine LIPE gene and to evaluate the possible association between three SNPs in the coding regions of this gene with the fatty acid composition of meat in a cattle population. Forty-three unrelated animals from different cattle breeds were re-sequenced and 21 SNPs were detected over approximately 2600 bp, five of these SNPs were novel.

Effect of ageing and μ-calpain markers on meat quality from Brangus steers finished on pasture.

Brangus steers (n=247) finished on pasture were used to evaluate the effects of post-mortem ageing and polymorphism CAPN1 316 and CAPN1 4751 markers on meat tenderness and objective colour measurements (CIEL*a*b*) of m. Longissimus dorsi. Ageing meat for 7 days decreased shear force (SF) by 13.