Post on 03-Jan-2016
Dan MorricalIowa State University
Extension Sheep Specialist
Carcass Component Growth
DGM:ISU
Lean tissueAdipose tissue Skeletal tissue
Components
DGM:ISU
AgeWeight
FatColor
FirmnessMuscle
Carcass value
DGM:ISU
Moderately leanHeavy muscled
Carcass value
DGM:ISU
Projected Target Market Weights
Fat Thickness (12-13th rib)
.15 .25 .35
Frame Size WETHERS
Small 92 116 140
Medium 97 126 154
Large 109 140 170 Tatum, 1992
Frame Size, Growth and Carcass Traits
DGM:ISU
Texas Rambouillet WethersSmall Medium Large
Carcass wt. 54 51 50
Backfat .18 .11 .07
Ribeye 2.02 2.05 1.98
Carcass Parameters, Constant weight 105 pounds
Small Medium Large
DOF 55 30 19
Slaughter weight 105 105 105
DP 51.6c 48.7d 47.9d
FT in 0.18 0.11 0.07
REA 2.2 2.05 1.98
% Choice 98.9 98.7 95.9
Nicholes
Carcass tissue weights of mature rams of two strains of Merinos of different mature size (Data from Butterfield et al., 1983a)
Weight (kg)
Whole Carcass Tissue Large n=3 Small n=3Sig. of
Diff.
Muscle 25.9 20.7 ***
Bone 6.4 4.9 **
Fat 26.7 18.8 **
Liveweight 116.5 90.9 ***
kgLiveweight 4 10 20 30 40 50 60 70 80 90 100=100
Carcass muscle 5 12 24 35 46 56 66 75 84 92 100=22.5Carcass bone 8 18 27 39 50 60 70 79 87 94 100=5.5Carcass fat 1 2 5 10 18 27 38 50 65 82 100=21.8
Percentage Maturity
The progress of carcass tissues of a Merino ram to maturity at 100 kg LW relative to the progress to maturity of shorn full LW
Carcass tissues as % of shorn full LW of mature rams of two strains of Merinoes of different mature size (Data from Butterfield et al., 1983
Percent of LW
Whole Carcass Tissue Large n=3 Small n=3Sig. of
Diff.
Muscle 22.3 22.8 NS
Bone 5.5 5.4 NS
Fat 23.0 20.7 *
LW 100.0 100.0
Fat partitions by sex
Fat partition % of total body fat Ewes as % of rams
Rams N=18 Ewes N=16
Subcutaneous* 30 33 1.1
Intermuscular*** 30 26 0.87
Total carcase 60 59 0.98
Kidney** 12 15 1.25
Omental 18 17 0.94
Mesenteric 7 7 1
Scrotal/Udder*** 3 2 0.67
Total non-carcase 40 41 1.02
Total Body 100 100
(Adapted from Thompson 1983)
Rams Ewes Ewes = 1
Rams =
27.1 23.9 1.13
4.8 4.1 1.16
13.5 18.1 0.75(Data from Fourie et all, 1970)
Muscle
Bone
Fat
% of LW Ratio
The carcass tissues as % of mature full LW of a combined group of Romney, Southdown and Romney Southdown crosses
Whole carcass tissue
Which group is better
DorsetDown
Hamp.Down
Ile deFrance
Southdown Suffolk Texel s.e. Mean
Age at slaughter (days) 218 236 253 234 249 247 6
Carcass wt (kg) 17 17.7 18.4 16.4 19.1 18.8 0.1
Daily carcass wt gain (g) 86 86 78 80 84 83 2
M. longissimus
Width A-mm 55.1 56.2 57 55.3 58 57.7 0.52
Depth B-mm 26.0a 25.5a 27.5b 25.8a 26.4a 27.4b 0.35
DorsetDown
Hamp.Down
Ile deFrance
Southdown Suffolk Texel s.e. Mean
Carcass conformation
(15 pt scale) 7.6bc 7.5bc 8.2c 8.3c 7.8c 7.9c 0.23
Tissue in carcass (g/kg)
lean 557a 562ab 571b 559ab 567ab 590c 3.2
separable fat 267cd 263bcd 255bc 273d 252b 240a 3.3
Daily tissue wt gain in carcass (g)
lean 47 45 43 43 46 47 1
separable fat 22 22 20 22 21 20 0.57
Ile DeFrance
Suff Coop DLS Rom Fin
Slaughter wt 95.5 92.4 95.5 93.3 93
Age (d.) 204 222 239 222 264
BF 0.15 0.18 0.16 0.12 0.20
REA 1.83 1.65 2.17 1.67 1.80
Fahmy etal 1992 J. Anim Sci 70:1365
Sire Breed Impact on Growth and Carcass
Carcass Traits by Sire Breed
Hamp Polypay
Gain 0.72 0.65
FE 6.60 6.70
Backfat 0.30 0.30
Bodywall 0.96 1.00
REA 2.43 2.29
YG 2.50 2.50
No impact on individual cuts
Meyer et al, 1993, SRJ 9:97
Effect of Sire Breed on carcass traits, adjusted for carcass weight
Dor Tex Mon Fin Rom
Slaughter wt 114 113 113 114 117
BF .25a .29b .24a .31b .29b
REA 2.35a 2.54b 2.41a 2.12c 2.24a
Freking and Leymaster. 2004. J. AnSci 82:3144
Evaluation of Texel, Columbia and Suffolk as Terminal Sires along with Finishing System
T S C BG FL
DP 51.1 52.0 51.0 51.0 51.7
BF 0.23 0.20 0.20 0.20 0.25
Bodywall .99a 1.07b 1.14c 1.00 1.12
REA 2.6 2.4 2.4 2.6 2.4
Morrical IASBR, 1994.
Restricted feeding on Growth and Carcass
Intake Level
100% 85% 70%
ADG 0.90 0.76 0.65
FE 3.3 3.4 3.4
% Water 49.6 51.2 51.5
% Protein 15.1 15.6 15.4
% Fat 31.1 29.0 28.2Murphy et al 1994 J. AnSci 72:3131
Impact of protein content and source on performance and carcass.(prolific crosses)
FM SBM CGM& BM Control
16% 16% 16% 13%
ADG .49a .41b .48a .40b
FE 4.99a 5.48b 5.11ab 5.76b
BF 0.15 0.17 0.16 0.18
REA 1.95 1.91 1.84 1.84
90 lb slaughter weightFahmy et all 1992 J. AniSci
Impact of Protein Source and Level on Suffolk Wether Growth and Performance
CP SBM SBM&F
13 16
ADG 0.98 1.00 0.98 0.97
FI 4.5 4.5 4.6 4.4
FE 4.6 4.6 4.7 4.6
BF 0.18 0.17 0.17 0.16
%lean 53.0 54.7 54.0 53.6
Ribeye Area 2.63 2.72 2.66 2.68
Neary et al, 1995
Frame Size and Feeding Method
Small Medium Large
Wheat Pasture gain 0.14 0.15 0.14
Feed lot gain 0.60 0.72 0.73
FE 7.2 6.6 5.6
Finishing System Impacts on CarcassC FC
Carcass Wt 63.1 57BF 0.35 0.3Bodywall 1.1 0.9
Age vs System. No effects on cuts.
Summary
Sex has an impact
Protein level
Older/backgrounding improves
cutability