ArticlePDF Available

Abstract and Figures

The heritability of quality traits (chemical composition, colour, tenderness and water-holding capacity) of the meat derivingfrom three muscles (Triceps brachii, Longissimus dorsi and Semitendinosus) was evaluated in 92 young Chianinabulls. The animals were raised on two farms with different feeding programs, and were slaughtered at approximately 19months of age. Single pair correlations were considered in order to evidence the relationships between the same traitsdetected in the three muscles and between all the traits of the same muscle.The h2 values range from 0.00 to 0.24 for the chemical composition, from 0.00 to 0.19 for colour parameters, from 0.03to 0.31 for those observed after 48 h, and from 0.00 to 0.08 for tenderness and water-holding capacity. The values werenot homogeneous for the three muscles. The most heritable trait was yellowness (b*48) in all three muscles, with valuesof 0.11 in the Longissimus dorsi, 0.23 in the Semitendinosus, and 0.31 in the Triceps brachii. Conversely, tendernessappeared to have a low heritability, as did the parameters relating to the water-holding capacity. Colour traitsobserved before and after 48 h of storage generally were significantly and positively correlated, indicating that certaincolour characteristics are maintained even after 48 h of storage. There was not always a close relationship between thetraits of each muscles: significant correlations existed between the Triceps brachii and the Longissimus dorsi muscles,confirming the similar quality traits of their meat, while there were considerable differences between these muscles andthe Semitendinosus.
Content may be subject to copyright.
Francesca Cecchi, Claudia Russo, Giovanna Preziuso, Dario Cianci
Dipartimento di Produzioni Animali. Università di Pisa, Italy.
Corresponding author: Dr. Francesca Cecchi. Dipartimento di Produzioni Animali. Facoltà di Medicina
Veterinaria, Università di Pisa. Viale delle Piagge 2, 56124 Pisa, Italy – Tel. +39 050 3139401 – Fax: +39 050
3139433 – Email: fcecchi@vet.unipi.it
Paper received October 17, 2003; accepted February 2, 2004
Genetic variability
of meat quality traits
in Chianina beef cattle
ABSTRACT
The heritability of quality traits (chemical composition, colour, tenderness and water-holding capacity) of the meat deriv-
ing from three muscles (Triceps brachii, Longissimus dorsi and Semitendinosus) was evaluated in 92 young Chianina
bulls. The animals were raised on two farms with different feeding programs, and were slaughtered at approximately 19
months of age. Single pair correlations were considered in order to evidence the relationships between the same traits
detected in the three muscles and between all the traits of the same muscle.
The h2values range from 0.00 to 0.24 for the chemical composition, from 0.00 to 0.19 for colour parameters, from 0.03
to 0.31 for those observed after 48 h, and from 0.00 to 0.08 for tenderness and water-holding capacity. The values were
not homogeneous for the three muscles. The most heritable trait was yellowness (b*48) in all three muscles, with val-
ues of 0.11 in the Longissimus dorsi, 0.23 in the Semitendinosus, and 0.31 in the Triceps brachii. Conversely, tender-
ness appeared to have a low heritability, as did the parameters relating to the water-holding capacity. Colour traits
observed before and after 48 h of storage generally were significantly and positively correlated, indicating that certain
colour characteristics are maintained even after 48 h of storage. There was not always a close relationship between the
traits of each muscles: significant correlations existed between the Triceps brachii and the Longissimus dorsi muscles,
confirming the similar quality traits of their meat, while there were considerable differences between these muscles and
the Semitendinosus.
Key words: Heritability, Correlations, Meat quality, Chianina breed.
RIASSUNTO
IL MIGLIORAMENTO GENETICO DELLA QUALITÀ
DELLA CARNE DELLA RAZZA CHIANINA: L’EREDITABILITÀ.
Numerosi studi hanno riportato stime di parametri genetici e fenotipici per l’efficienza riproduttiva, l’accrescimento, la
composizione e qualità della carcassa, mentre sono molto scarse le ricerche sulla variabilità genetica della qualità della
carne, per la quale si considerano preponderanti le influenze di origine ambientale. Scopo della presente ricerca è stato
quindi quello di stimare l’ereditabilità dei parametri di qualità della carne della razza Chianina.
Su tre muscoli (Triceps brachii, Longissimus dorsi e Semitendinosus) di 92 vitelloni Chianini, macellati a circa 19 mesi di
età e provenienti da due allevamenti che adottavano diete diverse, sono stati quindi analizzati i parametri di composi-
zione chimica, di colore, di tenerezza e di capacità di ritenzione idrica. Per evidenziare le relazioni esistenti tra tali para-
metri sono state impiegate le correlazioni semplici. I valori di h2ottenuti variano da 0,00 a 0,24 per la composizione chi-
mica, da 0,00 a 0,19 per i parametri di colore, da 0,03 a 0,31 per quelli rilevati dopo la conservazione e da 0,00 a 0,08
per i parametri di tenerezza e di potere di ritenzione idrica. Tali valori non sono risultati omogenei fra i tre muscoli. Il
parametro più ereditabile è risultato l’indice del giallo rilevato dopo 48 ore (b*48) in tutti e tre i muscoli, con valori di
0,11 nel Longissimus dorsi, 0,23 nel Semitendinosus e 0,31 nel Triceps brachii. La tenerezza sembra invece poco eredi-
tabile, così come i parametri relativi alla capacità di ritenzione idrica. Sono da evidenziare correlazioni significative e posi-
ITAL.J.ANIM.SCI. VOL. 3, 191-198, 2004 191
* I.J.A.S. Imp. 02/04 21-12-2005 12:54 Pagina 191
CECCHI et al.
192 ITAL.J.ANIM.SCI. VOL. 3, 191-198, 2004
tive tra i parametri relativi al colore, prima e dopo conservazione, indicando che alcune caratteristiche colorimetriche si
mantengono inalterate anche dopo 48 ore di conservazione in frigorifero. In questa ricerca viene inoltre confermata la
differenza qualitativa tra il muscolo Semitendinosus e gli altri muscoli analizzati. I risultati ottenuti evidenziano che non
è possibile disporre, attualmente, di uno o pochi parametri di semplice determinazione, che permettano di esprimere un
giudizio complessivo sulla qualità della carne, ma che sarebbe necessario identificare un indice globale che prenda in con-
siderazione più parametri qualitativi.
Parole chiave: Ereditabilità, Correlazioni, Qualità carne, Razza Chianina.
Introduction
Meat from Chianina cattle is of excellent quali-
ty (Lucifero et al., 1991; Poli, 1997; Russo and
Preziuso, 2000) and is highly appreciated on the
domestic market (Lucifero and Giorgetti, 1980;
Tartari and Benatti, 1990). However, quality traits
are extremely variable and operations regarding
genetic improvement as well as rearing technique
should be considered. The difficulties of any steps
taken in this direction are compounded by the high
number of traits that determine the quality, and the
need to choose the ones that are most pertinent to
the evaluations. An initial approach to the problem
concerns the establishing of a successful program of
genetic improvement with an acceptable hereditary
base for the chosen parameters. Numerous studies
have reported values of genetic or phenotypic traits
for reproductive efficiency, growth, composition and
carcass traits (Sartore and Di Stasio, 1990;
Mohiuddin, 1993; Koots et al., 1994), but very little
research has been carried out on the genetic vari-
ability of quality traits, which are considered to be
influenced mainly by environmental factors.
Up until now therefore, the estimation of the
genetic aspect of variability has not been
addressed in a decisive manner, and little infor-
mation is available in literature. Heritability stud-
ies have been performed almost exclusively for
tenderness because it is a critical aspect of beef
palatability (Morgan et al., 1991; Brooks et al.,
2000), however they offer varying results, ranging
from low to moderately high (Shackelford et al.,
1994; Gregory et al., 1995; Barkhouse et al., 1996;
Wheeler et al., 1996; O’Connor et al., 1997; Elzo et
al., 1998). Johnston et al. (2001) reports values for
heritability coefficients ranging from 0.19 to 0.39
for shear force, observed on the Longissimus dorsi
muscle in three cattle breeds (Belmont Red,
Brahman, and Santa Gertrudis). Marshall (1994)
reports heritability values for Warner-Blatzler
shear force ranging from 0.09 to 0.71, with an
average of 0.37; similar values (h2=0.26-0.31) were
summarized by Koch et al. (1982), Koots et al.
(1994) and Splan et al. (1998).
Recent estimates carried out on a large number
of carcasses (Burrow et al., 2001) showed that h2
values for meat tenderness were 0.19 in Bos taurus
cattle and 0.23 in both Bos taurus and Bos indicus
straightbred and their crossbreds. Wheeler et al.
(2001) reports 0.22 for tenderness in crossbred cat-
tle, while Riley et al (2003) reported h2values of
0.14, 0.14 and 0.03 for shear force measured after
7, 14 and 21 days respectively. Instead, for param-
eters relative to colour (L*, a* and b*), Aass (1996)
reports values ranging from 0.08 to 0.27.
As far as Chianina cattle are concerned, Franci
et al. (1996) reports non-homogeneous values in
the ten muscles analysed, with low heritability
coefficients for the meat colour traits ranging from
0.00 for L* and b* to 0.07 for a* and medium-low
coefficients for shear force on cooked meat (0.12)
and free water (0.26).
Considering these uncertainties, together with
the inherent risk in transferring results obtained
from different breeds and breeding conditions, the
aim of this work is to contribute to the knowledge
of the hereditary transmission of the Chianina
breed meat quality traits, by estimating heritabil-
ity and correlations.
Material and methods
Animals and meat instrumental measurements
and chemical analysis
Meat from three muscles (Triceps brachii,
* I.J.A.S. Imp. 02/04 21-12-2005 12:54 Pagina 192
HERITABILITY OF MEAT QUALITY TRAITS
ITAL.J.ANIM.SCI. VOL. 3, 191-198, 2004 193
Longissimus dorsi and Semitendinosus) of 92
young Chianina non-consanguineous bulls
raised in Tuscany on two breeding-farms was
analysed. Neither the sires nor the dams of each
family were related. Animals had been slaugh-
tered at approximately 19 months of age, after
attaining a live weight of about 770 kg. The
farms which supplied the bulls used in the test
followed different feeding systems; the first farm
used corn-silage as the basic fodder, while the
second provided hay.
Animals were chosen according to their genealog-
ical data, in order to form paternal half-sib groups.
In accordance with the commercial ageing peri-
ods for Chianina carcasses, the Triceps brachii (TB)
muscle was excised from the forequarters after
about 10 days of ageing, while the Longissimus dorsi
(Ld) and Semitendinosus (St) muscles were taken
from the hindquarters after 19 days of ageing.
In order to assess meat quality each muscle was
instrumentally analyzed (ASPA, 1991) as follows:
Meat colour, using a Minolta CR300 colourme-
ter (illuminant C), calibrated against a standard
white tile in the CIE L*a*b* system, which mea-
sures the value of lightness (L*), redness (a*), yel-
lowness (b*), Croma (C*) and Hue (H*) coordi-
nates (Renerre, 1982), by making three readings
for each sample consisting of a 2.5-cm thick slice of
meat covered with a polyethylene film and refrig-
erated for 45 min. at 4°C.
Meat colour after 48 h, on the same sample
kept at 4°C for 48 h to show any possible colour
changes during meat storage (L*48, a*48, b*48,
C*48 and H*48).
Water-holding capacity (WHC), determined
using two different methods:
- Drip loss, that is the percentage of water lost
from meat during storage at 4°C for 48 h in a
double-bottomed plastic container;
- Cooking loss, on the meat sample used for drip
loss and then cooked on a metal tray in an oven
at 180°C to an internal temperature of 75°C.
Tenderness measured as the shear force (kg) using
Warner Bratzler Shear applied to an Instron 1011, on
1-inch-diameter cylinders of raw and cooked meat.
Chemical analysis: dry matter (%), ether
extract (%), crude protein (%) and ash (%)
(A.O.A.C., 1990).
Statistical analysis
For the evaluation of the heritability, the
following mixed linear sire model was per-
formed using JMP, ver. 5.0 for PC, of the SAS
Institute (2002):
Yijk= µ+ si+ Hj+ bXijk + εijk where Yijk= consid-
ered parameters; µ= overall mean; si= random
effect of the ith sire (i=1, ..., 6); Hj= fixed effect of
the jth herd (j=1, 2); b= regression coefficient on
slaughter age in days; Xijk= slaughter age in days;
εijk = residual error.
All estimates of variance components for esti-
mates of heritability were obtained with a
derivate-free REML algorithm (JMP of the SAS
Institute, 2002). Because a sire model was used,
estimates of ratios of sire to total variance were
multiplied by four to yield heritability estimates.
Standard errors of heritabilities were approxi-
mated according to Becker (1984).
Single pair correlations were considered in
order to evidence the relationships between the
same trait detected in the three muscles, and
between all the traits of the same muscle, as well
as to estimate the correlations of colour parame-
ters measured before and after 48h storage.
Results and discussion
Heritability
Heritability coefficients varied from 0.00 to
0.24 for chemical composition, from 0.00 to 0.19 for
colour parameters before storage, from 0.03 to 0.31
for colour parameters observed after 48h of stor-
age, and from 0.00 to 0.08 for traits of tenderness
and water-holding capacity (Table 1).
For the three muscles, the heritability coeffi-
cients of the colour observed before storage were in
agreement with those determined by Franci et al.
(1996) for Chianina cattle, but lower than those
reported by Aass (1996). Nonetheless, heritability
coefficients improved after meat storage for 48 h
at +4°C; this was especially evident in the Triceps
brachii, for which there was an increase in values
that ranged from 0.02 to 0.05 for colour parame-
ters measured before storage and from 0.08 to 0.31
for those observed after 48h.
* I.J.A.S. Imp. 02/04 21-12-2005 12:54 Pagina 193
CECCHI et al.
194 ITAL.J.ANIM.SCI. VOL. 3, 191-198, 2004
The most heritable trait was the yellowness
measured after 48 h (b*48) in all three muscles,
with values of 0.11 in the Longissimus dorsi,
0.23 in the Semitendinosus, and 0.31 in the
Triceps brachii.
The “L*” and “L*48” parameters also gave
moderately elevated values, especially in the
Semitendinosus, with coefficients equivalent to
0.19 and 0.30 respectively.
On the other hand, tenderness had low heri-
tability, with coefficients falling within the range
reported by Barkhouse et al. (1996) and Riley et al.
(2003), though not compliant with those indicated
by Burrow et al. (2001), and other Authors (Koch
et al., 1982; Koots et al., 1994; Splan et al., 1998;
Johnston et al., 2001 and 2003).
Parameters relating to the water-holding
capacity (drip loss and cooking loss) also appeared
to have low heritability.
Correlations
Correlations among traits (Tables 2, 3, 4) con-
firm that the dry matter of meat is always posi-
tively linked to the ether extract (P0.01) and to
the crude proteins (P0.01), while the latter two
parameters are negatively correlated to each other
(P0.01), as reported in the literature for other
breeds (Russo and Preziuso, 1999).
As is to be expected, in the Triceps brachii and
Longissimus dorsi muscles the parameters relating
to meat colour measured before and after storage
for 48 h are correlated positively with each other in
a highly significant manner. This is partly
explained by the fact that some of them, such as
Chroma (C*) and Hue (H*), derive from the combi-
nation between the redness (a*) and the yellowness
(b*); the positive correlations between lightness
(L*) and the other traits were also interesting, indi-
cating that paler meat colour is usually accompa-
Table 1. Heritability coefficients and standard error (SE) estimates for meat quality
traits in the three muscles.
Muscle
Triceps brachii Longissimus dorsi Semitendinosus
h2SE h2SE h2SE
Chemical composition:
Dry matter 0.02 0.267 0.01 0.238 0.00 0.233
Ether extract 0.02 0.269 0.00 0.237 0.24 0.289
Ash 0.01 0.282 0.03 0.257 0.00 0.234
Crude protein 0.01 0.267 0.00 0.234 0.12 0.263
Meat colour:
L* 0.02 0.269 0.02 0.260 0.19 0.277
a* 0.02 0.268 0.00 0.234 0.05 0.244
b* 0.04 0.272 0.00 0.233 0.12 0.262
C* 0.02 0.269 0.00 0.233 0.05 0.246
H* 0.05 0.273 0.05 0.246 0.05 0.245
After 48 h of storage:
L* 0.08 0.279 0.03 0.240 0.03 0.301
a* 0.19 0.297 0.04 0.244 0.09 0.255
b* 0.31 0.313 0.11 0.259 0.23 0.285
C* 0.19 0.297 0.03 0.239 0.08 0.252
H* 0.13 0.288 0.12 0.261 0.06 0.247
Shear force:
on raw meat 0.08 0.278 0.00 0.233 0.00 0.232
on cooked meat 0.00 0.265 0.01 0.235 0.03 0.241
Water-holding capacity:
Drip loss 0.05 0.273 0.01 0.246 0.00 0.233
Cooking loss 0.01 0.267 0.01 0.239 0.05 0.245
* I.J.A.S. Imp. 02/04 21-12-2005 12:54 Pagina 194
HERITABILITY OF MEAT QUALITY TRAITS
ITAL.J.ANIM.SCI. VOL. 3, 191-198, 2004 195
Table 2. Significant correlations between parameters revealed on Triceps brachii muscle.
Chemical composition Meat colour After 48 h of storage Shear force Water-holding capacity
Dry Ether Ash Crude L* a* b* C* H* L*48 a*48 b*48 C*48 H*48 raw cooked Drip Cooking
matter extract protein meat meat loss loss
Chemical composition:
Dry matter 1.00
Ether extract 0.56** 1.00
Ash - 0.28** 1.00
Crude protein 0.56** - 0.37** 1.00
Meat colour:
L* 1.00
a* 0.31** 1.00
b* 0.52** 0.92** 1.00
C* 0.37** 0.99** 0.95** 1.00
H* 0.66** 0.55** 0.83** 0.63** 1.00
After 48 h of storage:
L* - 0.22* 0.63** 0.23** 0.37** 0.27** 0.45** 1.00
a* 0.47** 0.35** 0.45** 0.34** 1.00
b* 0.46** 0.38** 0.45** 0.20* 0.52** 0.92** 1.00
C* 0.46** 0.35** 0.44** 0.39** 0.99** 0.95** 1.00
H* 0.20* 0.33** 0.22* 0.25** 0.55** 0.48** 0.21* 1.00
Shear force:
on raw meat - 0.29** 0.22* 0.22* 0.20* 1.00
on cooked meat 0.22* 0.21* 0.52** 1.00
Water-holding capacity:
Drip loss 0.24* - 0.31** - 0.26** - 0.31** 1.00
Cooking loss - 0.21* 0.20* 0.19* 0.20* 0.21* 0.40** 0.41** 0.39** 1.00
*: P<0.05; **: P<0.01
Table 3. Significant correlations between parameters revealed on Longissimus dorsi muscle.
Chemical composition Meat colour After 48 h of storage Shear force Water-holding capacity
Dry Ether Ash Crude L* a* b* C* H* L*48 a*48 b*48 C*48 H*48 raw cooked drip cooking
matter extract protein meat meat loss loss
Chemical composition:
Dry matter 1.00
Ether extract 0.72** 1.00
Ash 1.00
Crude protein 0.41** - 0.33** 1.00
Meat colour:
L* 1.00
a* 0.35** 1.00
b* 0.21* 0.20* 0.61** 0.90** 1.00
C* 0.21* 0.42** 0.98** 0.94** 1.00
H* 0.78** 0.41** 0.75** 0.51** 1.00
After 48 h of storage:
L* 0.83** 0.27** 0.56** 0.36** 0.76** 1.00
a* 0.55** 0.46** 0.52** 0.23* 1.00
b* 0.40** 0.50** 0.57** 0.54** 0.44** 0.54** 0.91** 1.00
C* 0.20* 0.54** 0.51** 0.59** 0.24** 0.32** 0.97** 0.93** 1.00
H* 0.73** 0.42** 0.69** 0.82** 0.49** 0.21* 1.00
Shear force:
on raw meat 0.44** 1.00
on cooked meat - 0.18* 1.00
Water-holding capacity:
Drip loss - 0.24** - 0.20* 1.00
Cooking loss - 0.22* 0.20* 0.21* 0.23* 0.23* 0.27** 1.00
*: P<0.05; **: P<0.01
* I.J.A.S. Imp. 02/04 21-12-2005 12:54 Pagina 195
Table 4. Significant correlations between parameters revealed on Semitendinosus muscle.
Chemical composition Meat colour After 48 h of storage Shear force Water-holding capacity
Dry Ether Ash Crude L* a* b* C* H* L*48 a*48 b*48 C*48 H*48 raw cooked drip cooking
matter extract protein meat meat loss loss
Chemical composition:
Dry matter 1.00
Ether extract 0.34** 1.00
Ash 1.00
Crude protein 0.79** - 0.32** 1.00
Meat colour:
L* 0.29** 0.33** 1.00
a* 0.25** - 0.22* 1.00
b* 0.38** 0.70** 1.00
C* 0.22* 0.98** 0.82** 1.00
H* 0.25** 0.31** 0.78** 0.59** 1.00
After 48 h of storage:
L* 0.26** 0.88** 0.38** 0.73** 1.00
a* - 0.24** 0.42** 0.23* 0.44** -0.23* 1.00
b* 0.44** 0.49** 0.48** 0.20* 0.31** 0.81** 1.00
C* - 0.22** - 0.20* 0.49** 0.29** 0.44** 0.95** 0.89** 1.00
H* 0.56** 0.24* 0.40** 0.54** - 0.50** - 0.47** 1.00
Shear force:
on raw meat - 0.25** 1.00
on cooked meat 1.00
Water-holding capacity:
Drip loss 0.26** 0.26* - 0.25** - 0.27** 0.35** 1.00
Cooking loss 1.00
*: P<0.05; **: P<0.01
CECCHI et al.
196 ITAL.J.ANIM.SCI. VOL. 3, 191-198, 2004
nied by greater luminosity, which contributes to
conferring a “brilliant” aspect to the product.
In all muscles (Tables 2, 3, 4) the colour parame-
ters measured before storage were correlated in a
positive and significant manner with those evaluat-
ed after 48 h of conservation, in particular lightness
(r= 0.63, 0.83 and 0.88 respectively in Triceps brachii,
in Longissimus dorsi and in Semitendinosus).
Moreover, in the Triceps brachii and
Longissimus dorsi muscles, a*, b*, and C* mea-
sured after 48 h are significantly and positively cor-
related with water loss after cooking.
Significant correlations between tenderness
and redness (a* and a*48) and between tenderness
and Croma (C*48) are only observed in the Triceps
brachii muscle; furthermore, there is a significant
and positive correlation between shear force on
raw and cooked meat (r=0.52; P0.01).
Table 5 illustrates the correlations for each
quality trait among the three muscles: as can be
observed, the only parameters always correlated
in a significant manner were a*48, C*48 and drip
loss, while no significant correlations are recorded
for b*48, H* 48, and cooking loss.
The majority of significant correlations
between the Triceps brachii and Longissimus
dorsi muscles confirms the similar quality traits in
meat deriving from these two muscles, also in
accordance with the findings of another study
(Russo and Preziuso, 2000).
Conclusions
An examination of the results of heritability
coefficients and correlations between quality
traits led us to draw the following conclusions:
- many of the quality traits of Chianina meat are
affected by somatic variability factors: only the
heritability coefficients of the colour parameters
observed after storage are moderately-high, the
most heritable trait being the yellowness mea-
sured after 48 h (b*48) in all three muscles. The
heritability values for tenderness parameters
are low, indicating that their selective improve-
ment would be slow;
- in order to improve meat quality there are diffi-
culties involved in reducing the number of traits
to be analysed: correlations are normally
* I.J.A.S. Imp. 02/04 21-12-2005 12:54 Pagina 196
HERITABILITY OF MEAT QUALITY TRAITS
ITAL.J.ANIM.SCI. VOL. 3, 191-198, 2004 197
observed in each of the three muscles within the
same group of parameters (i.e. composition
parameters, colour parameters);
- the improvement of tenderness for the consumer
is not easy either since the shear force measured
on raw meat is not related to the shear force
measured on cooked meat; only the Triceps
brachii presents a positive relationship between
tenderness both before and after cooking.
These results underline the fact that, at the
moment, for improving quality traits of Chianina
meat it is important to pay particular attention to
the management problems in order to optimise the
heritable fraction of the variability. Moreover, it is
not possible to utilise one or two easily identified
traits alone for obtaining a complex evaluation of
meat quality, it is instead necessary to consider a
variety of different traits.
It would be interesting to identify a comprehen-
sive index capable of outlining the qualitative
aspects, but which also shows an acceptable heri-
tability, thus furthering prospects of genetic progress.
Research supported by “ARSIA”: “Plan for the
increase in value of the Tuscan bovine genetic
material and meat production”.
REFERENCES
AASS L., 1996. Variation in carcass meat quality traits
and their relations to growth in dual purpose cat-
tle. Livestock Prod. Sci. 46: 1-12.
AOAC, 1990. Official methods of analysis. 15th ed.
AOAC, Arlington, USA.
ASPA, 1991. Metodologie relative alla macellazione
degli animali di interesse zootecnico ed alla valu-
tazione e dissezione della loro carcassa. ISMEA,
Abete Grafica Spa, Roma, Italy.
BARKHOUSE, K. L., VAN VLECK,L.D.,CUNDIFF,L.V.,
KOOHMARAIE, M., LUNSTRA,D.D.,CROUSE,J.D.,
1996. Prediction of breeding values for tenderness
of market animals from measurements on bulls. J.
Anim. Sci. 74: 2612-2621.
BECKER, W. A., 1984. Manual of quantitative genetics.
Academic Enterprises 4th ed. Pullman Washington USA.
BROOKS,J.C.,BELEW,J.B.,GRIFFIN,D.B.,GWARTNEY,
B. L., HALE,D.S.,HENNING, W. R., JOHNSON,D.D.,
Table 5. Correlation for each parameter between muscles.
Tb 1vs Ld 2Tb 1 vs St 3Ld 2vs St 3
Meat colour:
L* 0.330** 0.332** 0.199
a* 0.291** 0.115 0.321**
b* 0.258* 0.009 0.181
C* 0.272** 0.083 0.259*
H* 0.221* 0.154 0.170
After 48 h of storage:
L* 0.330** 0.196 0.121
a* 0.283** 0.315** 0.268**
b* 0.096 0.145 0.108
C* 0.246* 0.268** 0.252*
H* 0.143 0.165 0.096
Shear force:
on raw meat 0.137 0.162 0.235*
on cooked meat 0.153 0.215* 0.198
Water-holding capacity:
Drip loss 0.246* 0.302** 0.368**
Cooking loss 0.150 0.055 0.021
*.P<0.05; **.P<0.01.
1 Tb:Triceps brachii;
2 Ld:Longissimus dorsi;
3 St:Semitendinosus.
* I.J.A.S. Imp. 02/04 21-12-2005 12:54 Pagina 197
CECCHI et al.
198 ITAL.J.ANIM.SCI. VOL. 3, 191-198, 2004
MORGAN,J.B.,PARRISH JR., F. C., REAGAN,J.O.,
SAVELL, J. W., 2000. National beef tenderness sur-
vey-1998. J. Anim. Sci. 78: 1852-1860.
BURROW, H. M., MOORE,S.S.,JOHNSTON,D.J.,
BARENDSE,W.,BINDON, B. M., 2001. Quantitative
and molecular genetic influences on properties of
beef: A review. Aust. J. Exp. Agric. 41: 893-919.
ELZO, M. A., WEST, R. L., JOHNSON,D.D.,WAKEMAN,D.
L., 1998. Genetic variation and prediction of addi-
tive and nonadditive genetic effects for six carcass
traits in an Angus-Brahman multibreed herd. J.
Anim. Sci. 76: 1810-1823.
FRANCI,O.,LUCIFERO, M., PUGLIESE,C.,BOZZI, R.,
ACCIAIOLI, A., FUNGHI, R., GIORGETTI, A., 1996.
Ereditabilità e ripetibilità di alcune caratteris-
tiche chimico-fisiche di 10 muscoli in vitelloni chi-
anini. Taurus 7 (spec.): 31-40.
GREGORY, K. E., CUNDIFF,L.V.,KOCK, R. M., 1995.
Genetic and phenotypic (co)variances for growth
and carcass traits of purebred and composite pop-
ulations of beef cattle. J. Anim. Sci. 73: 1920-1926.
JMP, 2002. J.M.P. User’s Guide ver. 5.0, S.A.S
Institute Inc., Ed. Cary (NC), U.S.A.
JOHNSTON,D.J.,REVERTER, A., ROBINSON,D.L.,FERGUSON,
D. M.,2001. Sources of variation in mechanical shear
forces measures of tenderness in beef from tropically
adapted genotypes, effects of data editing and their
implications for genetic parameter estimation. Aust.
J. Exp.Agric. 41: 991-996.
JOHNSTON,D.J.,REVERTER, A., FERGUSON,D.M.,
THOMPSON,J.M.,BURROW, H. M., 2003. Genetic
and phenotypic characterisation of animal, car-
cass, and meat quality traits from temperature
and tropically adapted beef breeds. 3 Meat quali-
ty traits. Aust. J. Agric. Res. 54: 135-147.
KOCH, R. M., CUNDIFF,L.V.,GREGORY, K. E., 1982.
Heritabilities and genetic, environmental and phe-
notypic correlations of carcass traits in a population
of diverse biological types and their implications in
selection programs. J. Anim. Sci. 55: 1319-1329.
KOOTS, K. R., GIBSON,J.P.,SMITH,C.,WILTON,J.W.,
1994. Analyses of published genetic parameter
estimates for beef production traits. 1. Heritability.
Anim. Breed. Abstr. 62: 309-338.
LUCIFERO, M., GIORGETTI, A., 1980. CNR Progetto
strategico: Nuovi orientamenti dei consumi e delle
produzioni alimentari. La carne e i fattori endogeni
ed esogeni all’animale che ne influenzano la pro-
duzione di qualità con particolare riferimento alla
specie bovina. ed. Grafiche Baudano, Torino, Italy.
LUCIFERO, M., POLI,B.M.,GIORGETTI, A., PARISI,G.,
1991. La produzione di carne di qualità con vitel-
loni di razza Chianina. Taurus 3 (spec.): 7-13.
MARSHALL, D. M., 1994. Breed differences and genetic
parameters for body composition traits in beef cat-
tle. J.Anim. Sci. 72: 2745-2755.
MOHIUDDIN, G., 1993. Estimates of genetic and pheno-
typic parameters of some performance traits in
beef cattle. Anim. Breed. Abstr. 61: 495-522.
MORGAN,J.B.,SAVELL,J.W.,HALE D. S., MILLER,R.K.,
GRIFFIN,D.B.,CROSS, H. R., SHACKELFORD,S.D.,
1991. National beef tenderness survey. J. Anim.
Sci. 69: 3274-3283.
O’CONNOR,S.F.,TATUM,J.D.,WULF,D.M.,GREEN R.
D., SMITH, G. C., 1997. Genetic effects on beef ten-
derness in Bos indicus composite and Bos taurus
cattle. J.Anim. Sci. 75: 1822-1830.
POLI, B. M., 1997. Le caratteristiche qualitative e
dietetiche della carne di vitellone Chianino. Proc.
Meet. Georgofili Acad.: Un prodotto di qualità: la
carne di razza Chianina, Firenze, Italy, IV: 21-43.
RENERRE, M., 1982. La couleur de la viande et sa
mesure. In: C.R.Z.V. Theix I.N.R.A ed., France,
Bulletin Technique. 47: 47-54.
RILEY,D.G.,CHASE,C.C.,HAMMOND,A.C.,WEST, R. L.,
2003. Estimated genetic parameters for palatabil-
ity traits of steaks from Brahman cattle. J. Anim.
Sci. 81: 54-60.
RUSSO,C.,PREZIUSO, G., 1999. Studio dei rapporti fra
parametri qualitativi della carne. Taurus 10
(spec.): 83-88.
RUSSO,C.,PREZIUSO, G., 2000. Caratteristiche qualita-
tive della carne proveniente da vitelloni di razza
Chianina: Confronto fra muscoli. Taurus 11
(spec.): 103-108.
SARTORE,G.,DISTASIO, L., 1990. Influenza dei fattori
genetici sulla produzione della carne bovina. pp
25-42 in Proc. Nat. Congr. Parliamo di…beef cat-
tle production, Fossano, Italy.
SHACKELFORD,S.D.,KOOHMARAIE, M., CUNDIFF,L.V.,
GREGORY, K. E., ROHRER, G. A., SAVELL, J. W., 1994.
Heritabilities and phenotypic and genetic correla-
tions for bovine postrigor calpastatin activity,
intramuscolar fat content, Warner-Bratzer shear
force, retail product yield, and growth rate. J.
Anim. Sci. 72: 857-863.
SPLAN,R.K.,CUNDIFF,L.V.,VAN VLECK, L. D., 1998.
Genetic parameters for sex-specific traits in beef
cattle. J.Anim. Sci. 76: 2272-2278.
TARTARI, E., BENATTI, G., 1990. L’influenza dei fattori
ambientali con particolare riferimento all’alimen-
tazione sulla produzione della carne. pp 43-58 in
Proc. Nat. Congr. Parliamo di…beef cattle produc-
tion, Fossano, Italy.
WHEELER, T. L., CUNDIFF,L.V.,KOCK, R. M., CROUSE,J.
D., 1996. Characterization of biological types of
cattle (Cycle IV): Carcass traits and longissimus
palatability. J. Anim. Sci. 74: 1023-1035.
WHEELER,T.L.,CUNDIFF,L.V.,SHACKELFORD, M. E.,
KOOHMARAIE, M., 2001. Characterization of biologi-
cal types of cattle (Cycle V): Carcass traits and
longissimus palatability. J.Anim. Sci. 79:1209-1222.
* I.J.A.S. Imp. 02/04 21-12-2005 12:54 Pagina 198
... Water-holding capacity and protein and ash content have low heritability (0.00 to 0.12) in LD and semitendinosus muscles in Chianina beef cattle (Cecchi et al., 2004); our results are in agreement. Water-holding capacity primarily depends on the pH of meat, muscle type, and the degree of marbling. ...
... We found stronger genetic than phenotypic correlations for meat quality traits, similar to the findings of Greeff et al. (2008) and Boukha et al. (2011). The strong, positive genetic and phenotypic correlations among the 3 colorimeter variants of LD and SM muscles are consistent with those reported by Page et al. (2001) and Cecchi et al. (2004). The stronger correlations at the genetic level among the color variables in LD and SM muscles indicate that nongenetic factors such as muscle pH and myoglobin oxidation may play significant roles in meat color dissociation. ...
... The stronger correlations at the genetic level among the color variables in LD and SM muscles indicate that nongenetic factors such as muscle pH and myoglobin oxidation may play significant roles in meat color dissociation. Similarly, Cecchi et al. (2004) reported phenotypic correlations of 0.10 to 0.32 in loin and round muscles of beef cattle. Lower genetic correlations between L* and a* in both LD and SM muscles reflect distinct nongenetic contributions to these traits. ...
Article
We estimated heritability (h²) and genetic and phenotypic correlations for carcass and meat quality traits of longissimus dorsi (LD) and semimembranosus (SM) muscles in 30-mo-old Hanwoo steers. Variance and covariance components were estimated using REML procedures under univariate and bivariate models. The mean carcass weight (CWT), eye muscle area (EMA), back fat thickness (BFT), and marbling score (MS) were 428.20 ± 46.30 kg, 87.38 ± 8.54 cm2, 13.00 ± 5.14 mm, and 5.21 ± 1.56, respectively. The mean CIE reflectance of meat lightness (L*), redness (a*), and yellowness (b*) were 40.01 ± 2.73, 22.37 ± 2.18, and 10.35 ± 1.46, respectively, in LD muscles and 36.33 ± 2.44, 22.91 ± 2.43, and 10.25 ± 1.65, respectively, in SM muscles. The mean Warner–Bratzler shear force (WBSF), intramuscular fat content (IMF), water-holding capacity (WHC), and protein and ash content in LD and SM muscles were 3.84 ± 0.96 and 6.52 ± 1.21 kg, 15.91 ± 4.39 and 5.10 ± 1.94%, 62.07 ± 3.38 and 71.61 ± 2.06%, 20.01 ± 1.39 and 21.34 ± 0.89%, and 0.80 ± 0.10 and 0.93 ± 0.07, respectively. The h² estimates of CWT, EMA, BFT, and MS were 0.51 ± 0.13, 0.45 ± 0.13, 0.29 ± 0.09, and 0.22 ± 0.08, respectively. The h² estimates were moderate for meat quality traits and were 0.37 ± 0.12, 0.40 ± 0.12, 0.33 ± 0.10, 0.33 ± 0.10, 0.30 ± 0.11, and 0.24 ± 0.09 for L*, WBSF, IMF, WHC, and protein and ash content, respectively, in LD muscle; estimates from SM muscle were comparatively low (0.08 ± 0.06 to 0.25 ± 0.09). Estimates of h² for a* and b* were also low (0.08 ± 0.06 to 0.13 ± 0.07). Carcass weight had a moderate, positive genetic correlation with EMA (0.60 ± 0.13) and a weak correlation with MS and BFT. The genetic correlations among the 3 colorimeter variants were strong and positive within and between muscles. Intramuscular fat content had moderate to strong and negative genetic correlations with WBSF (−0.49 ± 0.18), WHC (−0.99 ± 0.01), and protein (−0.93 ± 0.04) and ash content (−0.98 ± 0.06) in LD muscle, whereas the associations were less pronounced in SM muscle. In general, CWT and EMA had low genetic and phenotypic correlations with meat quality traits, which suggests that the traits are independent and have distinct genetic contributions in each muscle. Conversely, with few exceptions, meat quality traits had genetic and phenotypic correlations with MS and BFT. In conclusion, the estimated genetic parameters for carcass and meat quality traits could be used for genetic evaluation and breeding programs in Korean Hanwoo cattle populations. © 2017 American Society of Animal Science. All rights reserved.
... Meat quality is commercially important for the animal husbandry industry. It is affected by genetic background, management, nutrition and meat processing [21][22][23]. ...
Article
Full-text available
Hormone-sensitive lipase (HSL) is responsible for the decomposition of triglycerides in adipose tissue to release free fatty acids, and it is a key rate-limiting enzyme in the regulation of adipose tissue deposition and decomposition. The objective of this study was to evaluate the association between novel SNPs in the coding region of bovine HSL gene and carcass and meat quality traits of Chinese Simmental-cross steers. Two novel SNPs were genotyped and the 47 traits of carcass and meat quality traits were measured in the population studied. Statistical analysis revealed that the SNPs of HSL gene were associated with the carcass and meat quality traits. The individuals with TT genotypes of E1-276C>T showed significant higher dressing percentage, net meat rate, hind legs circumference, fat coverage rate, mesenteric fat and kidney fat (p < 0.05). E8-51C>T (P17S) also showed a significant association with the pH of beef and fatty acids content in Chinese Simmental cattle (p < 0.01). Our findings indicated that polymorphisms in HSL might be one of important genetic factors that influence carcass yield and meat quality in beef cattle, and it may be a useful marker for meat quality traits in future marker-assisted selection programs in beef cattle breeding and production.
... In the literature, only a few studies dealt with genetic aspects of water holding capacity and reported contradictory results. Riley et al. (2002), Johnston et al. (2003) and Cecchi et al. (2004 reported heritability estimates for CL of 0.26, 0.15, and 0.01, respectively. ...
Article
Preservation of biodiversity and genetic improvement of livestock populations are often considered to be antagonistic. Biodiversity affects meat quality (MQ) on different levels: among species (only three species yield 88% of the world’s meat); among breeds within species (there are more than 3000 cattle breeds worldwide, but about half are at an unknown risk of extinction, and only one-fourth of the others are not endangered); among animals within breed (in cattle populations with millions of individuals the median effective size is equivalent to only about 100 unrelated animals); and between alleles within animal genes (the inbreeding coefficients of individual animals are increasing with selection, and particularly genomic selection [GS]). Beef quality traits are very particular because they cannot be directly measured on living animals. The genetic improvement of beef quality can be pursued by different techniques. In chronological order, they are: phenotypic selection, which has created breed differentiation (not useful for MQ traits); selective breeding (heritability of beef quality traits varies considerably according to breed, trait and conditions; indirect selection through NIRS predictions, etc., (could be useful); the fixation of major gene mutations (the myostatin gene for double muscling, calpain (CAPN)-calpastatin (CAST) genes for beef tenderness; diacylglycerol O-Acyltransferase 1 for beef marbling, etc.); genomic and other omic approaches (strong increase in scientific studies, genome-wide association studies (GWAS), GS, gene network identification, etc.); the cloning of animals (not useful); and the cloning of tissues (cultivated meat).HIGHLIGHTS The biodiversity of beef cattle populations is threatened by globalisation, intensification, and (genomic) selection, which increase inbreeding; Indirect phenotyping (NIRS) and genomic selection (GS) will allow the genetic improvement of beef quality traits. Animal cloning has no practical use, and cell cloning (cultured meat) needs further research and ethical debate.
Article
Full-text available
The aims of this study were 1) to investigate the potential application of near-infrared spectroscopy (NIRS) to predict beef quality (BQ) traits, 2) to assess genetic variations of BQ measures and their predictions obtained by NIRS, and 3) to infer the genetic relationship between measures of BQ and their predictions. Young Piedmontese bulls (n = 1,230) were raised and fattened on 124 farms and slaughtered at the same commercial abattoir. The BQ traits evaluated were shear force (SF, kg), cooking loss (CL, %), drip loss (DL, %), lightness (L*), redness (a*), yellowness (b*), saturation index (SI), and hue angle. Near-infrared spectra were collected using a Foss NIRSystems 5000 instrument over a spectral range of 1,100 to 2,498 nm every 2 nm, in reflectance mode. After editing, prediction models were developed on a calibration subset (n = 268) using partial least squares regressions, followed by application of these models to the validation subset (n = 940). Estimations of (co)variance for measures of BQ and NIRS-based predictions were obtained through a set of bivariate Bayesian analyses on the validation subset. Near-infrared predictions were satisfactory for measurements of L* (R(2) = 0.64), a* (R(2) = 0.68), hue angle (R(2) = 0.81), and saturation index (R(2) = 0.59), but not for b*, DL, CL, and SF. The loss of additive genetic variance of predicted vs. measured L*, a*, DL, CL, and SF was generally high and was similar to the loss of residual variance, being a function of the calibration parameter R(2). As a consequence, estimated heritabilities of measures and predictions of BQ were similar for traits with high calibration R(2) values. Genetic correlations between BQ measures and predictions were high for all color traits and DL, and were greater than the corresponding phenotypic correlations, whereas both the phenotypic and genetic correlations for SF and CL were nil. Results suggest that NIRS-based predictions for color features and DL may be used as indicator traits to improve meat quality of the Piedmontese breed.
Article
Full-text available
Meat quality measures, including objective measures of tenderness (shear force and compression), were taken on 2 muscles [M. longissimus thoracis et lumborum (LTL) and M. semitendinosus (ST)] from 7566 carcasses from temperate (TEMP) and tropically adapted (TROP) beef cattle breeds. Animals were finished to 1 of 3 market carcass weight end-points (220, 280, or 340 kg) either on pasture or in a feedlot, and in 2 different geographic regions for TROP. Both the phenotypic and genetic expression of the traits were estimated at each market weight and for each finishing regime. Heritabilities and correlations between the traits were estimated for TEMP and TROP separately. Smaller additive variances and heritabilities were observed for temperate breeds compared with tropically adapted breeds for most of the traits studied. For TROP, the heritability of traits measured on the ST muscle [compression (ST_C), shear force (ST_SF), and L* Minolta lightness value (ST_L*)] was 0.27, 0.42, and 0.16, respectively, and for traits measured on the LTL muscle [compression (LTL_C), shear force (LTL_SF), L* Minolta lightness value (LTL_L*), a* Minolta redness value (LTL_a*), cooking loss% (LTL_CL%), and consumer assessed tenderness score (LTL_TEND)] 0.19, 0.30, 0.18, 0.13, 0.20, and 0.31, respectively. For TEMP, the heritability of traits measured on the ST muscle [ST_C, ST_SF, ST_L*, a* Minolta redness value (ST_a*), cooking loss % (ST_CL%)] was 0.12, 0.11, 0.17, 0.13, and 0.15, respectively, and of traits measured on the LTL muscle (LTL_C, LTL_SF, LTL_L, and LTL_TEND) were 0.08, 0.09, 0.17 and 0.18 respectively. Genetic correlations were moderate to high for tenderness measures (shear force and compression) between muscles for the same tenderness measure (e.g. LTL_SF and ST_SF was 0.46 for TROP) and within a muscle for the different measures (e.g. ST_C and ST_SF was 0.83 for TROP). Phenotypic and genetic correlations between LTL_L* and all objective measures of tenderness were negative (e.g. LTL_SF and LTL_L* for TROP was –0.40). The genetic relationship between LTL_SF and LTL_TEND was –0.79 and –0.49 for TROP and TEMP, respectively. Finishing system affected the phenotypic expression of all traits. Pasture-finished, compared with feedlot-finished, animals had higher shear force and compression measures, darker meat colour, and lower sensory tenderness scores for both TEMP and TROP. For TROP, heifers had higher shear force and compression measures, lower sensory tenderness scores, and darker meat colour (lower L* values) than steers. Genetic correlations between markets were generally high and close to unity with the exception of the ST_L*, LTL_L*, ST_C, and ST_SF for TEMP. Geographic region had little effect on the phenotypic and genetic expression of meat quality traits for TROP. Genetic correlations between finishing regimes for all traits were positive and close to unity, with the exception of ST_C and LTL_SF for TEMP, and LTL_L* and LTL_CL% for TROP. Genetic improvement of meat quality traits is a possibility for tropically adapted breeds given the moderate heritabilities, adequate phenotypic variance, generally favourable genetic correlations between traits, and little evidence of genotype by environment interactions.
Article
Full-text available
The scientific literature is reviewed to identify quantitative and molecular genetic influences on quantity and quality of beef. Genetic variation between breeds is of similar magnitude to genetic variation within breeds for many economically important traits. Differences between breeds are significant and large for most carcass and beef quality attributes, including beef tenderness, although differences for sensory juiciness and flavour are of little practical importance. For traits such as beef tenderness, between-breed differences may be more easily exploited than within-breed differences, because exceptional breeds are easier to identify than exceptional animals. Effects of heterosis on carcass and beef quality attributes are relatively small (3% or less), with most effects mediated through heterotic effects on weight. Carcass composition traits (e.g. carcass weight, fat thickness and marbling) are moderately to highly heritable. Most estimates of retail beef yield percentage are highly heritable, offering good potential for within-breed selection for the trait, although a moderate to strong antagonistic relationship exists between yield and marbling. This relationship needs to be considered in within-breed selection programs for yield percentage. Early estimates of heritability of objective measures of beef tenderness (Warner Bratzler shear force values) indicated tenderness was moderately to highly heritable. Recent estimates using larger numbers of carcasses and more discriminatory methods of analysis indicate that beef tenderness is lowly heritable in Bos taurus breeds and moderately heritable in Bos indicus and Bos indicus-derived breeds. Within breeds, measures of 24-h calpastatin activity are genetically strongly correlated with shear force values but are more heritable. However, phenotypic correlations between shear force values and 24-h calpastatin activities are low. There are also inconsistencies in relationships between these measurements across breeds. Low correlations between tenderness in different muscles, low to moderate heritabilities and inconsistent variation within- and between-breeds for traits such as 24-h calpastatin activity suggest that genetic improvement in beef tenderness may be difficult. The possibility exists that significant mitochondrial genetic effects occur for some carcass and beef quality attributes. A major gene for muscular hypertrophy in cattle significantly affects carcass and beef quality characteristics. Genome-wide screening of DNA markers indicates a number of putative Quantitative Trait Loci (QTL) associated with carcass and meat quality characteristics. Published data for these QTL are summarised. Strategies to combine quantitative and molecular genetic information to maximise genetic progress are discussed.
Article
Full-text available
Warner-Bratzler shear force measures of tenderness were taken on 2 muscles from 2661 carcasses from 3 tropically adapted breeds: Belmont Red, Brahman and Santa Gertrudis. The data were used to determine suitable methods of editing the raw data and to partition sources of variation for meat tenderness measured in 2 different muscles. The effect of different methods of electrical stimulation was examined: non-stimulated, extra low voltage or high voltage. The results showed stimulation method had a large effect on the mean and variance of the shear force. Non-stimulated slaughter groups were more variable than high voltage treated groups, which were more variable than low voltage treated groups. The effect of stimulation method was greater for shear force measured in M. longissimus dorsi than in M. semitendinosus. The variability in tenderness associated with different methods of electrical stimulation and the larger effect seen for the M. longissimus muscle suggest cold shortening, a processing effect, may have occurred in some of the slaughter groups. Several methods of editing outlier records were used and the effects of removing these records on the partitioning of variances among the independent variables of tenderness were examined. Removal of non-stimulated slaughter groups and other outliers resulted in a large reduction in slaughter group variance and residual variance, with the estimate of heritability for shear force of the M. longissimus increasing from 19 to 39%. Beef tenderness, as measured mechanically, could be improved by selection. However, the fluctuating heritability estimates reflect differences in handling pre- and post-slaughter and thus highlight difficulties in measuring tenderness consistently. The low genetic correlation between the 2 muscles (r g = 0.34) suggests improving overall tenderness of the carcass may be difficult. The large variance of the slaughter date effect within an abattoir (15% of the total variance) presents a problem in achieving consistently tender meat.
Article
Full-text available
Meat quality measures, including objective measures of tenderness (shear force and compression), were taken on 2 muscles [M. longissimus thoracis et lumborum (LTL) and M. semitendinosus (ST)] from 7566 carcasses from temperate (TEMP) and tropically adapted (TROP) beef cattle breeds. Animals were finished to 1 of 3 market carcass weight end-points (220, 280, or 340 kg) either on pasture or in a feedlot, and in 2 different geographic regions for TROP. Both the phenotypic and genetic expressions of the traits were estimated at each market weight and for each finishing regime. Heritabilities and correlations between the traits were estimated for TEMP and TROP separately. Smaller additive variances and heritabilities were observed for temperate breeds compared with tropically adapted breeds for most of the traits studied. For TROP, the heritability of traits measured on the ST muscle [compression (ST_C), shear force (ST_SF), and L* Minolta lightness value (ST_L*)] was 0.27, 0.42, and 0.16, respectively, and for traits measured on the LTL muscle [compression (LTL_C), shear force (LTL_SF), L* Minolta lightness value (LTL_L*), a* Minolta redness value (LTL_a*), cooking loss % (LTL_CL%), and consumer assessed tenderness score (LTL_TEND)] 0.19, 0.30, 0.18, 0.13, 0.20, and 0.31, respectively. For TEMP, the heritability of traits measured on the ST muscle [ST_C, ST_SF, ST_L*, a* Minolta redness value (ST_a*), cooking loss % (ST_CL%)] was 0.12, 0.11, 0.17, 0.13, and 0.15, respectively, and of traits measured on the LTL muscle (LTL_C, LTL_SF, LTL_L, and LTL_TEND) 0.08, 0.09, 0.17 and 0.18, respectively. Genetic correlations were moderate to high for tenderness measures (shear force and compression) between muscles for the same tenderness measure (e.g. LTL_SF and ST_SF was 0.46 for TROP) and within a muscle for the different measures (e.g. ST_C and ST_SF was 0.83 for TROP). Phenotypic and genetic correlations between LTL_L* and all objective measures of tenderness were negative (e.g. LTL_SF and LTL_L* for TROP was –0.40). The genetic relationship between LTL_SF and LTL_TEND was –0.79 and –0.49 for TROP and TEMP, respectively. Finishing system affected the phenotypic expression of all traits. Pasture-finished, compared with feedlot-finished, animals had higher shear force and compression measures, darker meat colour, and lower sensory tenderness scores for both TEMP and TROP. For TROP, heifers had higher shear force and compression measures, lower sensory tenderness scores, and darker meat colour (lower L* values) than steers. Genetic correlations between markets were generally high and close to unity with the exception of the ST_L*, LTL_L*, ST_C, and ST_SF for TEMP. Geographic region had little effect on the phenotypic and genetic expression of meat quality traits for TROP. Genetic correlations between finishing regimes for all traits were positive and close to unity, with the exception of ST_C and LTL_SF for TEMP, and LTL_L* and LTL_CL% for TROP. Genetic improvement of meat quality traits is a possibility for tropically adapted breeds given the moderate heritabilities, adequate phenotypic variance, generally favourable genetic correlations between traits, and little evidence of genotype by environment interactions. A R 0 2 0 8 7 G e n e t i c a n d n o n -g e n e t i c e f f e c t s o n b e e f q u a l i t y D . J . J o h n s t o n e t a l .
Article
Carcass and meat quality traits of Norwegian (NRF) dual purpose cattle were studied, and genetic parameters between these traits and growth rate were estimated. Data were recorded on 456 NRF bulls (n = 32 sires), performance tested at test stations from 1989 to 1991. Both ANOVA and REML were utilised for h2 estimations and gave about the same results. Carcass related heritabilities were lowest for fleshiness traits (0.05) and highest for length and fatness traits (0.55). Heritabilities for the meat quality traits ultimate pH and colour (Hunter-L∗a∗b) varied from 0.08 to 0.27, while h2 for intramuscular fat % in musculus latissimus dorsi was estimated to 0.51. Unfavourable genetic correlations were found between growth rate and various carcass fleshiness traits, and between growth rate and intramuscular fat. High growth rate was associated with longer carcasses, lower dressing %, poorer fleshiness and a decreased m. 1. dorsi area, combined with a decline in intramuscular fat content. The rg estimates between growth rate and lightness, redness and yellowness revealed that selection for daily gain will give correlated responses of lighter, but lower colour intensity meat.