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INTRODUCTION
The 2011 National Beef Quality Audit assessed
the status and progress made toward improving qual-
ity and consistency of U.S. cattle, carcasses, and beef
products (Igo et al., 2013). The only quality category
identifed by packers, food service buyers, and retail-
ers for which those sectors are willing to pay a pre-
mium was “eating satisfaction.” Tenderness, juici-
ness, and favor are the major determinants of beef
palatability and are often used to measure eating sat-
isfaction. Eating satisfaction is of great interest to the
beef industry as improving these traits should lead to
increased beef demand.
The beef industry has relied on marbling scores
as a major driver to determine USDA quality grades
and pricing of carcasses at wholesale level, with
higher quality grades expected to correspond to more
tender and palatable meat. Consumers also perceive
marbling as an indicator of tenderness and overall
meat quality, with consumer acceptance increasing
Genetic parameters for sensory traits in longissimus muscle and their associa-
tions with tenderness, marbling score, and intramuscular fat in Angus cattle
1
R. G. Mateescu,*
2
D. J. Garrick,† A. J. Garmyn,‡ D. L. VanOverbeke,§ G. G. Maf,§ and J. M. Reecy†
*Department of Animal Sciences, University of Florida, Gainesville 32611; †Department of Animal Science, Iowa
State University, Ames 50011; ‡Department of Animal and Food Sciences, Texas Tech University, Lubbock, 79409;
and §Department of Animal Science, Oklahoma State University, Stillwater 74078
ABSTRACT: The objective of this study was to
estimate heritabilities for sensory traits and genetic
correlations among sensory traits and with marbling
score (MS), Warner-Bratzler shear force (WBSF), and
intramuscular fat content (IMFC). Samples of LM
from 2,285 Angus cattle were obtained and fabricated
into steaks for laboratory analysis and 1,720 steaks
were analyzed by a trained sensory panel. Restricted
maximum likelihood procedures were used to obtain
estimates of variance and covariance components
under a multitrait animal model. Estimates of heri-
tability for MS, IMFC, WBSF, tenderness, juiciness,
and connective tissue traits were 0.67, 0.38, 0.19, 0.18,
0.06, and 0.25, respectively. The genetic correlations
of MS with tenderness, juiciness, and connective tis-
sue were estimated to be 0.57 ± 0.14, 1.00 ± 0.17, and
0.49 ± 0.13, all positive and strong. Estimated genetic
correlations of IMFC with tenderness, juiciness, and
connective tissue were 0.56 ± 0.16, 1.00 ± 0.21, and
0.50 ± 0.15, respectively. The genetic correlations of
WBSF with tenderness, juiciness, and connective tis-
sue were all favorable and estimated to be –0.99 ±
0.08, –0.33 ± 0.30 and –0.99 ± 0.07, respectively.
Strong and positive genetic correlations were esti-
mated between tenderness and juiciness (0.54 ± 0.28)
and between connective tissue and juiciness (0.58 ±
0.26). In general, genetic correlations were large and
favorable, which indicated that strong relationships
exist and similar gene and gene networks may control
MS, IMFC, and juiciness or WBSF, panel tenderness,
and connective tissue. The results from this study
confrm that MS currently used in selection breeding
programs has positive genetic correlations with ten-
derness and juiciness and, therefore, is an effective
indicator trait for the improvement of tenderness and
juiciness in beef. This study also indicated that a more
objective measure, particularly WBSF, a trait not easy
to improve through phenotypic selection, is an excel-
lent candidate trait for genomic selection aimed at
improving eating satisfaction.
Key words: beef, genetic parameters, marbling score, sensory traits, tenderness
© 2015 American Society of Animal Science. All rights reserved. J. Anim. Sci. 2015.93:21–27
doi:10.2527/jas2014-8405
1
This research was supported by Zoetis Animal Genetics.
2
Corresponding author: raluca@uf.edu
Received August 13, 2014.
Accepted October 28, 2014.
Published March 3, 2015