PREDICTION OF CARCASS TRAITS OF JAPANESE BLACK BULLS
AT SEVERAL AGES USING BODY MEASUREMENTS AND ULTRASONIC
ESTIMATE OF CARCASS TRAITS
SRI RACHMA APRILITA BUGIWATI
Jurusan Produksi Ternak, Fakultas Peternakan Universitas Hasanuddin, Makassar
ABSTRACT
The present research aims to estimate the mathematical equations for predicting
ultrasonic estimates of carcass traits at ten months after performance test (about 20
months of age) using body measurements and ultrasonic estimates of carcass traits at
earlier stages of performance test of Japanese Black bulls. This research was done at
Kagoshima and Miyazaki prefecture Livestock Experimental Stations Japan to collect the
ultrasonic estimates of carcass traits and body measurements data of Japanese Black bulls
at the end of performance test, four and ten month of after the performance test.
The ultrasonic estimates were MLTA7 and 13 (Musculus longissimus thoracis
areas between the 6th - 7th and 12th - 13th ribs, SFT (subcutaneous fat thickness), IMFT
(intermuscular fat thickness), RT (rib thickness) and MS (marbling score) and body
measurements such as BW (body weight), WH (wither height), HH (hip height), BL
(body length), CG (chest girth), CD (chest depth), CW (chest width), RL (rump length),
HW (hip width), TW (thurl width) and PBW (pin bone width) were taken regularly at the
end of performance test, four and ten months after the test. The data obtained was
statistically analyzed by the Step-wise multiple regression analysis
The highest accuracy to predict carcass traits of bulls ten months after the
performance test were taken by using the combining of ultrasonic estimates and body
measurement at four month after performance test (R2 = 69,9 – 92,0%). The combining
of independent variable between ultrasonic estimates of carcass traits and body
measurements could be increasing the accuracy of predicting carcass traits.
Key Word : Carcass traits, Ultrasound, Body Measurements, Performance Test
PENDUGAAN SIFAT KARKAS CALON PEJANTAN SAPI JEPANG HITAM
MENGGUNAKAN DIMENSI TUBUH DAN SIFAT KARKAS
ABSTRAK
Penelitian ini bertujuan untuk mendapatkan persamaan matematis untuk menduga
sifat karkas sapi Jepang hitam jantan saat 10 bulan setelah uji performans selesai (usia
sapi sekitar 20 bulan) menggunakan berbagai jenis dimensi tubuh serta berbagai sifat
karkas ternak pada saat fase dini uji performans. Penelitian dilaksanakan di Stasiun
Penelitian Peternakan Propinsi Kagoshima dan Miyazaki Jepang.
Data yang
dikumpulkan adalah data dugaan sifat karkas dan dimensi tubuh sapi Jepang hitam
1
jantan saat akhir uji performans, 4 dan 10 bulan setelah uji performans. Sifat karkas
diduga menggunakan alat ultrasonografi.
Sifat karkas yang diukur adalah luasan otot Longissimus dorsi antara tulang rusuk
ke-6-7 (MLTA7) dan antara tulang rusuk ke-12-13 (MLTA13), tebal lemak subkutan
(SFT), tebal lemak intermuskular (IMFT), tebal tulang rusuk (RT) dan penyebaran
marbling (MS). Dimensi tubuh yang diukur adalah berat badan, tinggi pundak, tinggi
punggung, panjang badan, lingkar dada, dalam dada, lebar dada, panjang kelangkang,
lebar punggung, lebar kelangkang, lebar tulang tapis. Seluruh data sifat karkas dan
dimensi tubuh diukur secara berkala saat akhir uji performans, 4 dan 10 bulan setelah uji
performans. Data dianalisis menggunakan analisis regresi berganda step-wise.
Kombinasi antara dugaan sifat karkas dan dimensi tubuh saat 4 bulan setelah uji
performans memiliki tingkat akurasi antara R2 = 69,9 – 92,0% untuk menduga sifat
karkas sapi Jepang hitam jantan saat 10 bulan setelah uji performans.
Kombinasi
penggunaan dugaan sifat karkas dan dimensi tubuh sebagai variabel bebas dalam
persamaan matematis dapat meningkatkan akurasi penduga sifat karkas saat 10 bulan
setelah uji performans.
Key Word : Sifat karkas, Alat Ultrasonografi, Dimensi Tubuh, Uji Performans
INTRODUCTION
Many years ago the growth rates of carcass traits were usually determined by
slaughter at some stages of fattening. It is difficult to clarify the patterns of continuous
growth of carcass during fattening.
As young sires for replacement are selected
according to performance testing records, thus their carcass abilities are unproven.
Therefore, we have to predict carcass performance on live bulls from performance test.
Many researches that predict some carcass traits on live cattle are known (Harada et al.
1985, Rahim et al. 1997; Sri Rachma et al. 1999).
Selection based on ultrasonic-measured traits in young cattle could allow more
rapid and economical progress. However, the estimates of several correlations among
ultrasonic estimates of carcass traits and body measurement were one of basic indicators
to estimate the meat quality and also best equation to predict carcass traits. Many
researchers were reported that the body measurement traits of live cattle are useful for
predicting quantitative and qualitative carcass traits (Kuchida et al. 1994). Most
researchers have found ultrasound to estimate carcass with an acceptable degree of
accuracy (Brethour, 1992).
Ultrasound measurements can also be very accurate
predictors of carcass yield, and reasonable predictors of carcass quality (Perkins et al.
2
1997). Other studies found that ultrasonic measurements of carcass traits can be used to
sort steers prior to the finishing phase, and to predict optimal slaughter end points
(Williams and Trenkle, 1997; Duckett and Klein, 1997; Hassen et al. 1998; Brethour,
2000; Field et al. 2000). In contrast, the information of relationships between body
measurements and ultrasonic estimates of carcass traits and early predicting by use of
ultrasound estimates of them and body measurements were very limited, especially on
Japanese Black bull.
The objective of this study are to estimate the equation for predicting carcass
composition at ten months after performance test (about 20 months of age) using body
measurements and ultrasonic estimates of carcass traits at earlier stages of performance
testing of Japanese Black bulls.
MATERIALS AND METHODS
Experimental Animals
Ultrasonic estimates of carcass traits and body measurements data were collected
from Japanese Black bulls on performance test in Kagoshima (156 head) and Miyazaki
(135 head) prefecture Livestock Experimental Stations. Ultrasonic estimates of carcass
traits, such as MLTA7 and 13 (Musculus longissimus thoracis areas between the 6th - 7th
and 12th -13th ribs, SFT (subcutaneous fat thickness), IMFT (intermuscular fat thickness),
RT (rib thickness) and MS (marbling score) and body measurements such as BW (body
weight), WH (wither height), HH (hip height), BL (body length), CG (chest girth), CD
(chest depth), CW (chest width), RL (rump length), HW (hip width), TW (thurl width)
and PBW (pin bone width) were taken regularly at the end of performance test, four and
ten months after the test.
The ultrasonic scanning was done on the left side of the body at two locations at
the 7th and 13th ribs for measuring all carcass traits.
Measurements for ultrasonic
estimates of carcass traits were taken by of Fujihira Super-Eye MEAT FHK Co. Ltd.,
Japan with B-mode electronic linear probe using 2 MHz and frequency: 27 x 147 mm.
Images were frozen and prints out scanograms were obtained by use of video-copy
machine (Aloka Co.Ltd., SSZ-300 S). Interpret tracing was measured by used of an
3
electric digitizer and computer system for each measurement to estimate MLTA, SFT,
IMFT and RT.
The body measurements were taken by used of a steel rod, calipers and cloth tape
calibrated in centimeters
Statistical Methods
Step-wise multiple regression analysis (Draper and Smith, 1966) was performed
in consideration of several variables to select and to adjust appropriate variables in order
to predict carcass traits ten months after performance test using the ultrasonic estimates
of carcass traits, body measurements of combination of both two traits at the end of
performance test and four months after the test.
Four independent variables were
considered with the critical F-value in each regression set at not less than 2.50.
RESULTS AND DISCUSSIONS
Currently, the targeted age for ultrasonic measurement for breeding stock is 365
days of age in order to predict the lean yield of their progeny at market age. Research is
presently looking at the potential of evaluating cattle over a wider age range for
adjustment to a standard age. All ratio of contribution for predicting carcass traits of
bulls ten months after the performance test using the body measurement at the end of
performance test data were lower than those of the four months after performance test
data, except MLTA7, MLTA13 and SFT (Table 1).
Ratio of contribution for predicting MLTA7, MLTA13 and SFT at ten months
after performance test by using body measurements at the end of performance test were
higher than those of four month after performance test. Conversely, IMFT, RT and MS
at then months after performance test could be predicted well by using data at four
months after the performance test than those at the end of performance test. Differences
of contribution ratio between the end of performance test and four months after the test to
predict the MLTA7, MLTA13 and SFT decreased of 0.7%, 2.2% and 2.6%, respectively.
Contrary, those for IMFT, RT and MS increased to 1.9%, 3.0% and 1.1%, respectively.
However, predictions of carcass traits using only body measurements were lower
accuracy. The low value of contribution ratio for all carcass traits at ten months after
performance test means that selection for carcass traits at ten months after performance
4
test using body measurement at the four months after performance test data not
necessarily lead to an equivalent increase the accuracy of predicting actual carcass traits.
Therefore other information, such as using ultrasonic estimates of carcass traits maybe
raises the ratio of contribution.
The WH at the end of performance test, as one of independent variable, has the
highest relationships with all carcass traits except SFT. Anyway, height of body at both
stages has the highest relationships with all carcass traits and it could be indicated that
height of body is the best indicator to predict carcass traits using only body measurement.
All ratio of contribution for predicting carcass traits of bulls ten months after the
performance test using the ultrasonic estimates of carcass traits at the end of performance
test data were lower than those of the four months after performance test data (Table 2).
Especially to predict the thickness of fat, rib and MS, the independent variables at
both stages were nearly similar such as the independent variables that used to predict the
SFT were SFT, RT, MLTA and MS while those for predicting the RT were RT, SFT,
MLTA and IMFT.
The percentage of variation explained using only the ultrasonic
estimates of carcass traits at four month after performance test were higher than those at
the end of performance test. It is indicated that the carcass traits ten months after the test
could be predicted well with high accuracy by multiple regression equations that adopted
ultrasonic estimates of carcass traits obtained at four month after performance test. The
conclusion is that these carcass traits at the time when bulls are used as sires (ten months
after performance test) could be predicted well by use of ultrasonic estimates about four
months after performance test.
All ratio of contribution for predicting carcass traits of bulls ten months after the
performance test using the ultrasonic estimates of carcass traits and body measurements
at the end of performance test data were lower than those of the four months after
performance test data (Table 3).
The ratios of contribution of MLTA7 and MLTA13 were higher than other carcass
traits. It means that accuracy to predict MLTA7 and MLTA13 using the combination of
ultrasonic estimates of carcass traits and body measurement at the end of performance
test or four months after performance test are the best one.
SFT was accurately predicted with regard to SFT also, with the standardized
5
partial regression coefficient of 0.73 using the data at the end of performance test and
0.91 using the data at four months after performance test. Other variables that are added
can increase the accuracy up to R2 = 52.3% using the data at the end of performance test
and R2 = 81.9% using the data at four months after performance test.
IMFT was moderately predicted with a similar first variable of IMFT.
The
standardized partial regression coefficients for IMFT the end and four months after
performance test were 0.50 and 0.80, respectively. However, the percentage of variation
explained for IMFT at the end of performance test was low (34.9%).
It was also
suggested that WH affected IMFT considerably because of relatively high standard
partial regression coefficient (0.51).
RT at ten months after performance test was predicted more accurately using the
combination of body measurements and ultrasonic estimates of carcass traits at four
months after performance test (R2 =75.8%).
The ratios of contribution to predict MS was 35.6% that adopted MS, CD,
MLTA13 and IMFT at the end of performance test and 78.2% by adopted MS, MLTA13,
BW and IMFT at four months after performance test. Ratio of contribution to predict MS
ten months after performance test by use of the data at the end of performance test was
higher than those reported by Harada et al. (1985) on Japanese Black bull (R2 = 29.3%)
and by Sri Rachma et al. (1999) on Japanese Black bulls (R2 = 23.6%). Nevertheless, the
results of this study was proved the conclusion of Harada et al. (1985) that MS ten
months after the test could be predicted more accurately using ultrasonic estimates of
carcass traits and body measurements four months after performance test. It indicated
that marbling in M.longissimus thoracis area is better to be distinguished using both of
ultrasonic estimates of carcass traits and body measurements at about 16 months of age.
It also reported by use of Japanese Black steers (Fukuhara et al. 1989) and bulls (Harada,
1982).
It show that the marbling score ten months after performance test will be
predicted more accurately by use of ultrasonic estimates and body measurements taken at
several months later period from the end of performance test.
The accuracy of predicting carcass traits at ten months after performance test (16
month of ages) could be increased using of the combination of ultrasonic estimates of
carcass traits and body measurements at four months after performance test. Sri Rachma
6
et al. (1999) reported a slightly higher of ratios contribution to predict MLTA7, MLTA13,
SFT, RT, IMFT and MS ten months after performance test by use of the data at the end of
performance test of 45.4%, 59.1%, 29.0%, 19.7%, 20.5% and 23.6%, respectively and
those for four months after performance test were 59.7%, 68.8%, 78.6%, 55.2%, 62.9%
and 41.7% respectively in Japanese Black bulls in Kagoshima. Differences of ratios of
contribution could be influence by number of cattle as source of analysis and also
changed by measuring system and tools.
CONCLUSION
1. Selection of bulls as candidate sires, based on these predicted of ultrasonic estimates
of carcass traits and body measurements four months after performance test will be
possible enough in relatively early growing stages of bulls.
2. The combination traits of ultrasonic estimates of carcass traits and body
measurements are also could be added as information to predict carcass traits with
relatively high accuracy.
ACKNOWLEDGMENT
Appreciation is also expressed to Prof. Hiroshi Harada from Miyazaki University Japan
for his valuable support and precious guidance during the preparation up to the
accomplishment of this work is much recognized and acknowledged.
REFERENCES
Brethour, J. R. 1992. The repeatability and accuracy of ultrasound in measuring
backfat in cattle. J. Anim. Sci. 70:1039–1044.
-------------------. 2000. Using serial ultrasound measures to generate models of
marbling and backfat thickness changes in feedlot cattle. J. Anim. Sci.
78:2055-2061.
Draper, N., and. Smith, H. 1966. Applied Regression Analysis, WilesInterscience. N.Y., 163-216.
Duckett, S.K, and. Klein, T.A. 1997. Monitoring lipid and muscle deposition in feedlot
steers of different breeds using realtime ultrasound. J.Anim.Sci. 75 (Suppl.1):113
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Field, C.M., Williams, A.R.., McKinley, W.B., Jefcoat, L., and. Smith, R.G. 2000.
Use of live animal carcass ultrasound in stocker grazing in Mississippi. J.
Anim. Sci. 78 Abstract.(Suppl. 1):43.
Fukuhara, R., Moriya, K .and Harada, H. 1989. Estimation of parameters and sire
evaluation for carcass characteristics with special reference to yield grade of
the new beef carcass grading standards (in Japanese with English summary).
Jpn.Zootech.Sci. 60:1128-1134.
Harada, H. 1982 . The use of ultrasonic to estimate carcass traits in live beef
cattle. Bull.Fac.of Agric.Miyazaki Univ. Japan. 29:1-65 (in Japanese).
Harada,H., Moriya, K. and Fukuhara, R. .1985. Early prediction on carcass traits
of beef bulls. Jpn.J.Zootech.Sci. 56:250-256.
Hassen, A., Wilson, D.E.,. Willham, R.L., Rouse, G..H..,and. Trenkle. A.H. 1998.
Evaluation of ultrasound measurements of fat thickness and longissimus
muscle area in feedlot cattle: Assessment of accuracy and repeatability. Can.
J. Anim. Sci. 78:277-285
Kuchida, K. Yamagishi, T., Takeda, H., and Yamaki., K. 1994. The estimation of
beef carcass traits using computer image analysis for body measurement in
Japanese Black steers. Anim. Sci. Technol. (Jpn.). 65:401-406.
Perkins, T.L. Paschal, J.C., Tipton, N.C., and. DeLaZerda, M.J. 1997. Ultrasonic
prediction of quality grade and percent retail cuts in beef cattle. J. Anim.
Sci. 75. Abstract. (Suppl. 1):178.
Rahim,L. Harada, H., .and Fukuhara, R.. 1997. Early prediction on carcass traits
of fattening steers by use of real-time ultrasonography. Anim.Sci.Technol.
(Jpn.). 68:622-630.
Sri Rachma, A.T.D., Harada, H and. Fukuhara. R. 1999. Studies on predicting
carcass traits as one of criteria for selecting Japanese Black bulls.
Bull.Fac.of Agric. Miyazaki Univ. Japan. 46:61-67.
Williams, A.C. ,and Trenkle. A. .1997. Sorting feedlot steers using ultrasound
estimates of backfat at the 12th and 13th rib prior to the finishing phase.
J. Anim. Sci. 75 Abstract. (Suppl. 1):55.
8
A : Scanner position to measure MLTA between the 6th - 7 th ribs; B : scanner position
to measure SFT, IMFT and RT; C : scanner position to measure MLTA at 13 th ribs
Figure 1. Scanning Positions at 7th and 13th ribs
A – M : Withers height
C – N : Hip height
K – F : Body length
BGIG’B : Chest girth
B–I
: Chest depth
G – G’
P–F
D – D’
E – E’
F – F’
: Chest width
: Rump length
: Hip width
: Thurl width
: Pin bone width
Figure 2. The Measurement Positions of Body Measurements
9
Table 1. Prediction of carcass traits at ten months after performance test using body measurement
Dependent
Independent Variables a
R2
variable
(Standard partial regression coefficient)
(%)
MLTA7
WH
(-0.23)
TW
(0.19)
CW
(0.16)
PBW
(-0.12)
6.2
CG
(0.22)
WH
(-0.19)
CD
(-0.19)
TW
(0.12)
5.5
MLTA13
WH
(-0.17)
BW
(0.16)
CD
(0.15)
TW
(0.11)
9.4
WH
(-0.16)
CG
(0.14)
BW
(0.11)
PBW
(0.11)
7.2
SFT
HH
(-0.53)
WH
(0.24)
CG
(0.19)
RL
(0.11)
11.6
TW
(-0.24)
CG
(0.18)
HW
(0.17)
HH
(-0.16)
9.0
IMFT
WH
(-0.09)
CD
(0.08)
CW
(0.05)
HW
(0.05)
1.9
HH
(-0.22)
WH
(0.14)
CG
(0.11)
BW
(0.09)
3.8
RT
WH
(-0.19)
CG
(0.11)
BL
(0.09)
CD
(0.09)
3.8
BW
(0.15)
HH
(-0.15)
CG
(0.12)
PBW
(0.07)
6.8
MS
WH
(-0.22)
CD
(0.21)
CW
(0.13)
PBW
(-0.11)
6.0
HH
(-0.25)
CW
(0.12)
CG
(0.10)
TW
(0.08)
7.1
MLTA7 and 13: Musculus longissimus thoracis areas between the 6th-7th and 12th-13th ribs; SFT :
subcutaneous fat thickness; IMFT : intermuscular fat thickness; RT : rib thickness; MS : marbling score;
BW : body weight; WH : wither height; HH :hip height; BL : body length; CG : chest girth; CD : chest
depth; CW : chest width; RL : rump length; HW : hip width: TW : thurl width; PBW : pin bone width.
a
Upper : the end of performance test; Lower : four months after performance test ;
R2 : Ratio of contribution
Table 2. Prediction of carcass traits at ten months after performance test using ultrasonic
estimates of carcass traits
Dependent
Independent Variables a
variable
(Standard partial regression coefficient)
MLTA7
MLTA7
(0.38)
MLTA13 (0.29)
IMFT
(-0.15)
MS
(-0.08)
MLTA7
(0.79)
IMFT
(-0.09)
RT
(0.07)
MS
(-0.05)
MLTA13
MLTA13 (0.70)
MLTA7
(0.07)
MS
(-0.06)
RT
(-0.01)
MLTA13 (0.89)
IMFT
(0.03)
SFT
(0.02)
MS
(-0.02)
SFT
SFT
(0.74)
RT
(-0.19)
MLTA13 (0.03)
MS
(-0.01)
SFT
(0.92)
MS
(-0.06)
RT
(-0.04)
MLTA7 (0.04)
IMFT
IMFT
(0.51)
RT
(-0.15)
MLTA13 (0.09)
MS
(0.06)
IMFT
(0.79)
SFT
(0.03)
MLTA13 (0.03)
MS
(-0.03)
RT
RT
(0.23)
SFT
(0.15)
MLTA13 (0.13)
IMFT
(0.12)
RT
(0.68)
IMFT
(0.15)
MLTA13 (0.07)
SFT
(0.04)
MS
MS
(0.41)
IMFT
(0.11)
MLTA13 (0.11)
SFT
(0.04)
MS
(0.83)
MLTA13 (0.08)
IMFT
(0.04)
SFT
(0.03)
Abbreviations are same as Table 1.
10
R2
(%)
33.9
64.0
54.0
81.1
45.9
79.6
22.5
63.5
19.5
64.7
22.0
73.6
Table 3. Prediction of carcass traits at ten months after performance test using ultrasonic
estimates of carcass traits and body measurements
Dependent
Independent Variables a
variable
(Standard partial regression coefficient)
MLTA7
MLTA7
(0.42)
HH
(0.34)
MLTA13 (0.23)
IMFT
(-0.09)
MLTA7
(0.89)
HH
(0.34)
WH
(-0.22)
BW
(-0.08)
MLTA13
MLTA13 (0.62)
CD
(0.25)
MLTA7
(0.09)
MS
(-0.04)
MLTA13 (0.89)
CD
(0.15)
IMFT
(0.02)
CW
(-0.07)
SFT
SFT
(0.73)
RL
(0.35)
BW
(-0.24)
RT
(-0.13)
SFT
(0.91)
MLTA7
(0.11)
BW
(-0.07)
MS
(-0.07)
IMFT
IMFT
(0.50)
RL
(0.24)
RT
(-0.16)
MLTA13 (0.13)
IMFT
(0.80)
WH
(0.51)
HH
(-0.34)
HW
(-0.10)
RT
RT
(0.26)
CD
(0.24)
MLTA13 (0.17)
SFT
(0.14)
RT
(0.69)
IMFT
(0.14)
MLTA13 (0.09)
SFT
(0.04)
MS
MS
(0.39)
CD
(0.21)
MLTA13 (0.13)
IMFT
(0.11)
MS
(0.81)
MLTA13 (0.10)
BW
(0.07)
IMFT
(0.04)
Abbreviations are same as Table 1.
11
R2
(%)
77.1
88.7
80.2
92.0
52.3
81.9
34.9
69.9
43.4
75.8
35.6
78.2