|Johnson, D - UNIV. FLORIDA|
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 27, 2005
Publication Date: March 3, 2006
Citation: Casas, E., White, S.N., Wheeler, T.L., Shackelford, S.D., Koohmaraie, M., Riley, D.G., Chase, C.C. Jr., Johnson, D.D., Smith, T.P. 2006. Effects of calpastatin and u-calpain markers in beef cattle on tenderness traits. Journal of Animal Science. 84:520-525. Interpretive Summary: Markers for two genes associated with differences in beef tenderness can both be used to improve meat quality. It was not known if the effects of these two commercially available gene markers would add together or if the effect of one gene marker would be masked by the other. The markers were tested in two diverse populations of cattle (Bos indicus which is important in subtropical U.S. beef production and Bos taurus) and crosses between these populations. Regardless of the population, the markers effects on tenderness were nearly independent and, therefore, can both be used to genetically improve tenderness. In populations where alternative forms of both markers are present, cattle breeders can use both gene markers to attempt to improve beef tenderness.
Technical Abstract: The objective of this study was to assess the association of single nucleotide polymorphisms (SNP) developed at the calpastatin (CAST) and u–calpain (CAPN1) genes with meat tenderness and palatability traits in populations with diverse genetic background. Three populations were used in the study. One from Bos taurus that included crossbred animals derived from Hereford, Angus, Red Angus, Limousin, Charolais, Gelbvieh, and Simmental (GPE7; n = 539). Another from Bos taurus with Bos indicus influence that included crossbred animals from Hereford, Angus, Brangus, Beefmaster, Bonsmara, and Romosinuano (GPE8; n = 580). A third from Bos indicus comprised from purebred Brahman (STARS; n = 444). Traits evaluated were meat tenderness measured as Warner-Bratzler shear force at 14 d postmortem (WBSF; kg), tenderness score, juiciness, and flavor intensity. The last three were measured by a trained sensory panel. An SNP at the CAST gene had a significant (P < 0.003) effect on WBSF and tenderness score in the GPE7 and GPE8 populations. Animals inheriting the TT genotype had meat more tender than those inheriting the CC genotype. The marker at the CAPN1 gene was significant (P < 0.03) for tenderness score in GPE7 and GPE8. Animals inheriting the CC genotype had meat more tender than those inheriting the TT genotype. Markers at the CAST and CAPN1 genes were associated with flavor intensity in the GPE8 population. Animals inheriting the CC genotype at CAST and the TT genotype at CAPN1 produced steaks with an intense flavor when compared to the other genotypes. The only interaction between CAST and CAPN1 was detected (P < 0.05) for WBSF on GPE8. Markers developed at the calpastatin and u–calpain genes are suitable to be used in conjunction to identify animals with the genetic potential to produce meat that is more tender.