Livestock Production Science 67 (2001) 293–295
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Short communication
Prediction of kid carcass composition by use of joint dissection
a ,
*
b a a¨
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A. Arguello
, J. Capote , R. Gines , J.L. Lopez
a
Animal Production, Veterinary Faculty, Las Palmas University, 35416-Arucas, Las Palmas, Spain b
Canary Agronomic Science Institute, Apartment 60, La Laguna, Tenerife, Spain
Received 10 September 1998; received in revised form 18 August 1999; accepted 23 May 2000
Abstract
Forty-seven Canary Caprine Group kids (6–15 kg body weight) were taken from the experimental flocks of Las Palmas de Gran Canarias University and the Canary Agronomic Science Institute and slaughtered. Their carcasses were halved and the left side was dissected into the major tissues. Linear regression analyses were used for predicting carcass tissue composition, using half carcass weight and joints tissue weights as independent variables. Taking account of the relative economic values of the joints, the most cost-effective predictor of carcass tissue composition was a combination of half carcass weight and
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shoulder dissection with an r of 0.79, 0.81, 0.72 and 0.70 for muscle, bone, and subcutaneous and intermuscular carcass fat, respectively. 2001 Elsevier Science B.V. All rights reserved.
Keywords: Canary Caprine Group goat; Shoulder joint; Carcass; Tissue composition
1. Introduction significant reduction in precision (Colomer-Rocher et
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al., 1987; Lopez, 1990).
Carcass tissue composition is a very important Recently, shoulder joint dissection was used for factor for determining carcass quality, due to its high prediction of carcass composition with good results variability and its effects on the commercial value of in lambs (El Karim et al., 1988; Cameron, 1992). a carcass. Complete carcass dissection into fat, lean The shoulder was chosen because it can be easily and bone is the best method for evaluation of carcass disjointed and it is not of a high commercial value. composition, but it is very expensive and time Kempster and Jones (1986) found that the best end consuming. Therefore, many researchers have sug- neck and shoulder joints gave a good composition gested the use of half-carcass dissection, without a prediction in relation to cost in lambs.
Some workers have used sample joints as predic-tors of carcass composition in goats (El Shalat, 1993; Teixeira et al., 1995), but the Canary Caprine Group (CCG) was not included in either study.
*Corresponding author. Tel.: 134-928-454-361; fax: 1
34-This note examines carcass tissue composition and
928-451-142.
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E-mail address: [email protected] (A. Arguello) its relationship with half-carcass weight and five
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294 A. Arguello et al. / Livestock Production Science 67 (2001) 293 –295
Table 1 joints in CCG goats. Therefore, the main objective of
Means and standard errors (g) of half carcass and joints weight the study was to define the use of five joint tissue
Variable Mean Standard error weights as predictors of carcass tissue composition.
Half carcass 2525.00 62.24
Shoulder 507.19 12.93
Neck 293.94 13.79 2. Material and methods
Long leg 767.91 20.19
Flanks 271.32 10.82
Forty-seven CCG male kids (natural and
artificial-Ribs 586.19 18.20
ly reared) were taken from the experimental herds of
Table 2
Regression coefficients, residual standard deviations (RSD) and linear equations for predicting carcass tissue composition using half carcass a
weight and joints tissue weights (g)
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Dep. var. ( y) Ind. var. (x) r RSD Slope Intercept
Carcass muscle Half Car. 0.71 126.07 0.46 137.12
Rib muscle 0.62 145.24 2.63 586.15
Flank muscle 0.70 130.53 4.85 668.82
Long leg muscle 0.88 81.55 2.45 151.63
Neck muscle 0.44 176.70 3.48 808.03
Shoulder muscle 0.41 181.30 2.75 495.84
Half Car. 0.79 109.08 0.38 250.01
Shoulder muscle 1.34
Carcass bone Half Car. 0.77 62.88 0.26 73.20
Rib bone 0.40 101.09 1.87 345.94
Long leg muscle 0.63 79.40 2.33 223.37
Neck bone 0.38 103.46 1.74 579.58
Shoulder bone 0.73 67.87 4.24 120.74
Half Car. 0.81 57.82 0.16 45.01
Shoulder bone 1.93
Carcass Half Car. 0.16 43.69 0.01 19.66
subcutaneous Rib Sub. fat 0.58 36.79 2.14 78.99
fat Flank Sub. fat 0.62 34.93 2.15 73.57
Long leg Sub. fat 0.17 51.91 1.92 85.14
Neck Sub. fat 0.21 52.35 2.67 105.67
Shoulder Sub. fat 0.67 33.02 2.47 77.06
Half Car. 0.72 34.45 0.03 1.09
Shoulder Sub. fat 2.32
Carcass Half Car. 0.51 52.32 0.10 2165.79
intermuscular Rib Int. fat 0.80 27.64 3.06 21.52
fat Flank Int. fat 0.84 24.49 4.37 13.69
Long leg Int. fat 0.88 21.73 2.85 15.31
Neck Int. fat 0.40 49.69 4.46 46.30
Shoulder Int. fat 0.55 41.82 3.96 36.50
Half Car. 0.70 30.42 0.06 2109.63
Shoulder Int. fat 2.72
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A. Arguello et al. / Livestock Production Science 67 (2001) 293 –295 295
Las Palmas de Gran Canarias University and the dent variables (Table 2), a good prediction was Canary Agronomic Science Institute. Only male kids obtained. The higher quality joints (ribs and long were used because most female kids in the flock leg) were good predictors of carcass tissue com-were destined for breeding. Kids com-were slaughtered position, with the exception of carcass subcutaneous (after a 24-h fast) at 6–15 kg live weight. After fat predicted from the long leg subcutaneous fat, but slaughter, carcasses were cooled at 48C for 24 h. their dissection will reduce the carcass price marked-Carcasses were halved carefully and the left side was ly. In contrast to El Karim et al. (1988), who studied dissected into muscle, subcutaneous fat, intermuscu- Sudan Desert sheep, the neck tissue weights were not lar fat, bone and remainder (major blood vessels, good predictors of tissue carcass composition in kids. ligaments, tendons and thick connective tissue sheets In conclusion, the shoulder tissue composition was associated with some muscles). The technique used not the best predictor for carcass tissue composition. was similar to the standard methods for goat carcass However, taking into account the low cost of the evaluation by Colomer-Rocher et al. (1987). Linear shoulder dissection and carcass weight, it may be a regression analyses was conducted (SPSS v. 8.0 cost-effective approach to use it as a predictor of programme) for predicting carcass tissue composi- carcass tissue composition.
tion, using half carcass weight and joint tissue weights as independent variables. The regression
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coefficients (r ) and residual standard deviations (RSD) were used to assess the accuracy of
predic-References tors.
Cameron, N.D., 1992. Correlated responses in slaughter and carcass traits of crossbred progeny to selection for carcass lean
3. Results and discussion content in sheep. Anim. Prod. 54, 379–388.
Colomer-Rocher, F., Morand-Fehr, P., Kirton, A.H., 1987.
Stan-Means and standard errors of half carcass and joint dard methods and procedures for goat carcass evaluation, jointing and tissue separation. Livest. Prod. Sci. 17, 149–159.
weights are shown in Table 1. All characteristics had
El Karim, A.I.A., Owen, J.B., Whitaker, C.J., 1988. Measurement
a large variation reflecting the wide range of live
of slaughter weight, side weight, carcass joints and their
weight at slaughter. In the Canary Islands, the CCG association with carcass composition of two types of Sudan kids are slaughtered at a low live weight in order to Desert Sheep. J. Agri. Sci. 110 (1), 65–69.
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save the high milk production for cheese (Lopez, El Shalat, A.A., 1993. Density values of carcass joints of local Egyptian goats. Small Rumin. Res. 12 (2), 221–225.
1990).
2 Kempster, A.J., Jones, D.W., 1986. A comparison of alternative
The r , RSD, slope and intercept for predicting
methods for predicting the carcass composition of crossbred
carcass tissue weights using half carcass weight and lambs of different breeds and crosses. Meat Sci. 18 (2), joint tissue weights as independent variables are 89–110.
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shown in Table 2. The half carcass weight was a Lopez, J.L., 1990. Estudio Etnologico y Productivo de la Ag-´
rupacion Caprina Canaria. Tesis Doctoral, Universidad de
good predictor of carcass muscle and bone weight. In
Zaragoza, Spain.
contrast, the prediction of fat composition was poor.
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Teixeira, A., Delfa, R., Gonzalez, C., Gosalvez, L., Tor, M., 1995. 2
The shoulder dissection showed a medium r but, Use of three joints as predictors of carcass and body fat depots when the regression analyses were calculated using in Blanca Celtiberica goats. Options Mediterraeenes, Seria A,
