Meat Tenderness Genetic and Genomic Variation Sources in Commercial Beef Cattle

Published in: Journal of Food Quality

1. María Salud Rubio Lozano,
2. Selene Alfaro-Zavala, 
3. Ana María Sifuentes-Rincón,
4. Gaspar Manuel Parra-Bracamonte, et al.

To assess genetic group (GGR; Bos indicus [Bi], Bos taurus [Bt] and crosses [BtxBi]) and to confirm the calpain (CAPN316 and CAPN4751) and calpastatin (CAST-T1) single nucleotide polymorphism (SNP) effects on Warner–Bratzler shear force (WBSF), 196 animals under commercial conditions were analyzed. A model was fitted including the effect of GGR and considering residuals as adjusted WBSF (aWBSF). Another model was fitted to evaluate the SNP effect on aWBSF. Allele substitution effect (α) and combined favorable alleles in CAPN and CAST on aWBSF were evaluated. GGR showed a significant effect (P < 0.0001) on WBSF; Bt and BtxBi had the lower WBSF. CAPN316 showed significant effect on aWBSF with an α = −0.549 kg. The combined effect of CAPN and CAST showed significant (P < 0.0056) reduction on aWBSF of 0.239 kg by favorable allele. The results remarked the importance of GGR and confirmed CAPN316 and combined effect of CAPN and CAST on prediction of meat tenderness.

Knowledge of main factors related to tenderness, as a key related factor to beef consumer satisfaction, would serve as a resource for commercial beef classification and management under slaughterhouse conditions. Confirmation on combined marker effects provides strong validation for marker-assisted management use of these technologies under industry conditions. Additionally, the presented results may be used as a reference for research in the beef industry aimed to provide improvement on beef tenderness to the final product.

http://onlinelibrary.wiley.com/doi/10.1111/jfq.12185/abstract

Articulo IGF y su Relación con características de crecimiento

POLYMORPHISMS IN IGF1 GENE AND THEIR EFFECT ON GROWTH TRAITS IN MEXICAN BEEF CATTLE


Xochitl De la Rosa Reyna
Humberto Martínez Montoya
Victoria Valerio Castrellón
Ana M. Sifuentes Rincón
Manuel Parra Bracamonte
Williams Arellano Vera

ABSTRACT

The IGF1 gene (insulin-like growth factor 1) is a candidate gene for marker-assisted selection strategies. A SNP in the promoter region (IGF1/Sna BI) has been reported and associated with production traits in several cattle breeds. Here, we report its allelic frequencies evaluated in Charolais and Beefmaster breeds, and confirm its association with three growth traits: weaning weight (PD), weaning weight adjusted to 210 days (P210) and preweaning weight gain (GPD) in Charolais breed. In addition, we designed a strategy to search in these breeds for a new polymorphism in four coding regions of the gene. A C/A transversion was detected in intron 4, but it did not show an association with the growth traits tested.

The SNP (IGF1/SnaBI), is proposed as a potential selection marker in Mexican Charolais cattle, the validation of its association with PD, P210 and GDP, could complement the genetic evaluations of this breed through marker-assisted management strategies. The characterization of the gene IGF1 in Mexican populations of Beefmaster and Charolais cattle permitted the identification of a new SNP in this gene, which should be the subject of future studies to determine its role as a molecular marker.

Key words: IGF1; SNP IGF1/Sna BI; Polymorphism; Charolais; Beefmaster

Ya en Genetics and Molecular Research Evolution and Technology.
http://www.funpecrp.com.br/gmr2008b/index.asp