Muscle score: its usefulness in describing the potential yield of saleable meat from live steers and their carcasses

1993 ◽  
Vol 33 (3) ◽  
pp. 275 ◽  
Author(s):  
D Perry ◽  
WA McKiernan ◽  
AP Yeates
Keyword(s):  
Standard Deviation ◽  
Subcutaneous Fat ◽  
Carcass Weight ◽  
Coefficient Of Determination ◽  
Muscle Area ◽  
Potential Yield ◽  
Frame Size ◽  
Eye Muscle ◽  
Meat Yield ◽  
Residual Standard Deviation

Domestic trade weight steers (149) were assessed visually for subcutaneous fat and then given a live muscle score based on the thickness and convexity of their shape relative to frame size, having adjusted for subcutaneous fat. After slaughter, carcasses were given visually assessed carcass muscle scores based on the same critera. Fat depths at the P8 site and 12-13th eye muscle area were measured. Half of each carcass was boned-out into primal joints with subcutaneous fat trimmed to 6 mm. The weights of these joints plus meat trim (85% visual lean) were added to obtain the weight of saleable meat. The weight of fat trimmed from the carcass, primal joints, and meat trimmings during the bone-out process was added to obtain weight of fat trim. The assessors did not give steers with a greater subcutaneous fat depth better muscle scores when scoring for muscle and intermuscular fat. There was a negative correlation between live muscle score and P8 fat depth (-0.37), and no significant correlation between carcass muscle score and P8 fat depth. The associations between muscle score and yield of saleable meat were investigated using multiple regression techniques, with fat depth and muscle score sequentially added after weight in the model. The coefficient of determination and the residual standard deviation were compared at each stage. For saleable meat yield (kg), liveweight and carcass weight were the main contributors to the variation explained by the models fitted. For saleable meat yield as a percentage of carcass weight, most of the variation accounted for by the models fitted was explained by fat depth, muscle score, and eye muscle area. When added after weight and fat depth in regression models, muscle score significantly increased the coefficient of determination in all cases, with an associated decrease in the residual standard deviation. The effect was strongest for percentage of saleable meat. At the same weight and fat depth, animals or carcasses with better muscle scores produced more saleable meat.

Meat yield and subjective muscle scores in medium weight steers

1993 ◽  
Vol 33 (7) ◽  
pp. 825 ◽  
Author(s):  
D Perry ◽  
AP Yeates ◽  
WA McKiernan
Keyword(s):  
Negative Correlation ◽  
Regression Models ◽  
Subcutaneous Fat ◽  
Carcass Weight ◽  
Muscle Area ◽  
Eye Muscle ◽  
Meat Yield ◽  
Lean Meat ◽  
Intermuscular Fat ◽  
Medium Weight

The association between visually assessed muscle scores on live steers and their carcasses, eye muscle area, and the yield of saleable and lean meat was determined on 156 steers of mixed breeds (mean carcass weight 282 kg, mean P8 fat depth 13 mm). The contribution of subcutaneous and intermuscular fat to differences in saleable meat yield was also investigated. There was a negative correlation between P8 fat depth and both live ( r = -0.21) and carcass muscle score (r. = -0.31); therefore, the assessors were not scoring fatter steers as having better shape. The correlation between live and carcass muscle scores was 0.79. The correlation between carcass muscle score and eye muscle area was 0.58. When live muscle score, carcass muscle score, or eye muscle area was included in regression models already containing weight and fat depth, there was a significant (P<0.001) increase in the amount of variation in saleable and lean meat yield explained by the models. At the same liveweight and fat depth, a change in live muscle score from C (moderately muscled) to B (well muscled) was accompanied by an increase of 1.7% in saleable meat and 2.2% in lean meat, when these were expressed as a percentage of carcass weight. The equivalent change in carcass muscle score in carcasses of the same weight and f a t depth was accompanied by an increase of 1.9% in saleable meat and 2.4% in lean meat. The increased weight of saleable meat was not due to an increase in the dissected fat content of the meat. Weight of subcutaneous fat decreased as muscle score increased (P<0.01). There was no significant association between the amount of intermuscular fat and either live or carcass muscle score (r. = -0.075 and -0.18, respectively).

Elliotdale and crossbred lambs: growth rate, wool production, fat depth, saleable meat yield, carcass composition and muscle content of selected cuts

1992 ◽  
Vol 32 (4) ◽  
pp. 429 ◽  
Author(s):  
DL Hopkins ◽  
KD Gilbert ◽  
KL Pirlot ◽  
AHK Roberts
Keyword(s):  
Subcutaneous Fat ◽  
Subjective Assessment ◽  
Carcass Composition ◽  
Carcass Weight ◽  
Width Ratio ◽  
Muscle Area ◽  
Eye Muscle ◽  
Meat Yield ◽  
Significant Difference ◽  
Carcass Parameters

Growth and carcass parameters were studied for 62 second-cross lambs (Poll Dorset rams over Border Leicester x Merino ewes) and 55 purebred Elliottdale lambs. Second cross lambs grew faster (P<0.001) from weaning to the first slaughter time than Elliottdale lambs and consequently weighed more and had heavier carcasses. Elliottdale lambs produced significantly (P<0.001) more wool between birth and weaning. The slope of the relationship between GR (tissue depth over the 12th rib 110 mm from the midline) and carcass weight was 1.24 � 0.23 mm/kg for second cross lambs and 0.82 � 0.17 mm/kg for Elliottdale lambs, indicating the latter lambs were leaner at heavier weights. Measures of subcutaneous fat depth at the 5th/6th and 12th/13th ribs were similar when carcass weight differences were considered for a subsample of 21 second cross and 26 purebred Elliottdale lambs. Subjective assessment of fat distribution and carcass conformation by 2 assessors revealed a significant (P<0.001) difference between breeds; second cross lambs having a better conformation. Saleable meat yield, carcass composition, and muscle content of several cuts were determined for a subsample of lambs. At a common side weight of 8 kg there was no significant difference in saleable meat yield. At this weight, crossbred lambs had a significantly (P<0.05) higher muscle content (505 g/kg) than Elliottdale lambs (480 g/kg). Fat content was similar at 300 g/kg with crossbred lambs having significantly (P<0.05) less bone (190 g/kg) than Elliottdale lambs (2 10 g/kg). The legs of carcasses from crossbred lambs were shown to contain significantly more muscle than those of Elliottdales (206 v. 195 g/kg). Carcass weight explained some of the variation in weight of leg and forequarter muscle (r2 = 0.63 and 0.61). This was improved by including an assessment for conformation from 1 assessor (r2 = 0.69 and 0.64). Eye muscle area at the 12th rib did not add significantly to the prediction; it was not different between breeds, nor was its depth to width ratio different between breeds. The pH measurements of the M. longissimus thoracis et lumborum were similar between breeds.

scholarly journals Prediction of the Hind-Leg Muscles Weight of Yearling Dairy-Beef Steers Using Carcass Weight, Wither Height and Ultrasound Carcass Measurements

Animals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 651 ◽  
Author(s):  
Addisu Hailu Addis ◽  
Hugh Thomas Blair ◽  
Stephen Todd Morris ◽  
Paul Richard Kenyon ◽  
Nicola Maria Schreurs
Keyword(s):  
Prediction Models ◽  
Age Groups ◽  
Carcass Weight ◽  
Beef Steers ◽  
Prediction Equations ◽  
Muscle Area ◽  
Prediction Ability ◽  
Eye Muscle ◽  
Meat Yield ◽  
Leg Muscles

Prediction equations have been widely utilized for carcass classification and grading systems in older beef cattle. However, the equations are mostly relevant for common beef breeds and 18 to 24 month old animals; there are no equations suitable for yearling, dairy-origin cattle. Therefore, this study developed prediction models using 60 dairy-origin, 8 to 12 month old steers to indicate saleable meat yield from hind-legs, which would assist with carcass classification and grading. Fat depth over the rump, rib fat depth, and eye muscle area between the 12th and 13th ribs were measured using ultrasound, and wither height was recorded one week prior to slaughter. The muscles from the hind-leg were retrieved 24 h after slaughter. Prediction equations were modeled for the hind-leg muscles weight using carcass weight, wither height, eye muscle area, rump, and rib fat depths as predictors. Carcass weight explained 61.5% of the variation in hind-leg muscles weight, and eye muscle area explained 39.9% (p < 0.05). Their combination in multivariate analysis explained 63.5% of the variation in hind-leg muscles weight. The R2 of the prediction in univariate and multivariate analyses was improved when data were analyzed per age group. Additional explanatory traits for yearling steers, including body length, hearth girth, and muscle depth and dimensions measured using video image analysis scanning (VIAscan), could improve the prediction ability of saleable meat yield from yearling dairy beef steers across the slaughter age groups.

Growth and carcass characteristics of crossbred and straightbred Hereford steers. II. Carcass measurements and composition

1981 ◽  
Vol 32 (1) ◽  
pp. 171 ◽  
Author(s):  
JM Thompson ◽  
R Barlow
Keyword(s):  
Subcutaneous Fat ◽  
Carcass Characteristics ◽  
Allometric Equation ◽  
The Body ◽  
The Other ◽  
Carcass Weight ◽  
Muscle Area ◽  
Eye Muscle ◽  
Fat Thickness ◽  
Breed Crosses

The effect of sire breed on the growth and development of carcass characteristics was examined in 104 steer carcasses, over the weight range of c. 300 to 600 kg liveweight. The carcasses were obtained from 28 straightbred Hereford, 27 Brahman x Hereford, 23 Simmental x Hereford and 26 Friesian x Hereford steers, which were grown on pasture and slaughtered in four groups when the Herefords weighed c. 270, 370, 470 and 570 kg liveweight. Changes in carcass characteristics with weight were examined by using the linear form of the allometric equation (log10Y = log10A+blog10X). As liveweight increased, the proportion of carcass in the body increased (b = 1.152). At the same liveweight, Brahman cross steers had heavier carcasses than the Hereford steers, which were heavier than either the Simmental or Friesian cross steers (P < 0.05). Fat thickness at the 12th-13th rib site, and kidney and channel fat weight both increased at a proportionally faster rate than carcass weight (b = 1.511 and 1 567 respectively). At the same carcass weight, Hereford and Brahman cross carcasses had a greater fat thickness than Simmental and Friesian cross carcasses (P i 0.05). Differences between sire breeds in kidney and channel fat weight were not significant (P > 0.05). C:rcass length and eye muscle area increased at a proportionally slower rate than carcass weight (b = 0.268 and 0.466 respectively). At the same carcass weight, Friesian cross carcasses were longer, and Simmental cross carcasses had a larger eye muscle area than the other breed crosses (P < 0.05). As total side weight increased, the proportions of subcutaneous and intermuscular fatAincreased (b = 1.554 and 1.535 respectively), and the proportions of muscle and bone decreased (b = 0.938 and 0.676 respectively). At the same side weight, the Hereford and Brahman cross carcasses had more subcutaneous fat than the Simmental and Friesian cross carcasses (P < 0.05). The Hereford carcasses had more intermuscular fat than the Simmental cross carcasses, which had more muscle than the other breed crosses (P < 0.05). Friesian cross carcasses had more bone than the Simmental crosses, with Brahman cross and Hereford carcasses having the least bone (P < 0.05). Brahman cross carcasses had a higher conformation score than the Simmental cross and Hereford carcasses, the Friesian cross carcasses having the lowest (P < 0.05). Samples of the M. longissimus from Brahman cross carcasses had a higher Warner-Bratzler shear force than samples from the other breed crosses (P < 0.05).

Lamb carcass characteristics. 2. Estimation of the percentage of saleable cuts for carcasses prepared as 'trim' and traditional cuts using carcass weight, fat depth, eye muscle area, sex, and conformation score

1995 ◽  
Vol 35 (2) ◽  
pp. 161 ◽  
Author(s):  
DL Hopkins ◽  
JSA Wotton ◽  
DJ Gamble ◽  
WR Atkinson
Keyword(s):  
Full Range ◽  
Subcutaneous Fat ◽  
Carcass Weight ◽  
Significant Variable ◽  
Leg Length ◽  
Muscle Area ◽  
Eye Muscle ◽  
Percentage Yield ◽  
Ewe Lamb ◽  
Shoulder Blade

Carcass data were obtained for 172 lambs (86 ewes, 86 cryptorchids) of hot carcass weight (HCW) 16.2-28.7 kg and fat depth at the GR site (12th rib) 5-21 mm. Of these, 85 carcasses (42 ewe, 43 cryptorchid) were prepared into the full range of boneless, heavily trimmed cuts ('trim' lamb) and the remaining 87 (44 ewe, 43 cryptorchid) into traditional, trimmed bone-in cuts. Two methods of determining M. longissimus thoracis et lumborum area (EMA) produced strongly correlated results (r = 0.94; P<0.001). Conformation score using the EUROP system (1 is best, 5 is worst) was negatively correlated (r = -0.31 to -0.53; P<0.05) with measures of EMA and HCW, which were positively correlated (r = 0.64-0.71; P<0.001). Leg length was positively correlated (r = 0.36-0.76; P<0.001) with measures of EMA and HCW. Models were developed to predict the percentage yield of saleable cuts for carcasses prepared into a range of trim and traditional cuts. These identified GR as the most significant variable, so models based on GR were developed for each yield type. HCW and EMA significantly (P<0.05) improved the accuracy of estimated yield in addition to GR. By contrast, when HCW and measurements of subcutaneous fat depth over the eye muscle (FDC) were combined, EMA was not significant (P>0.05). For estimation of the percentage yield of traditional cuts, conformation score as given by an assessor significantly (P<0.05) improved the accuracy of estimation when combined with HCW and FDC. This model indicates that as conformation score increases, yield increases. Overall in terms of predicting yield, conformation score was of little value when combined with currently used carcass measures. There was a significant (P<0.05) effect of sex on the prediction of yield for 2 combinations of trim cuts that included the eye of loin. Sex also influenced (P<0.05) the prediction of yield based on traditional cuts. Where sex was significant, ewe lamb carcasses had less saleable meat by <0.5-1.0%, depending on yield type. For 4 of the trim cuts (boneless loin, eye of loin, fillet, shoulder blade), EMA added significantly (P<0.05) to the estimation of the proportions of the cuts; at constant carcass weight and fatness as indicated by GR, increases in EMA are predicted to lead to an increase in the proportion of loin cuts and a decrease in shoulder blade. For carcasses prepared into traditional cuts, EMA added significantly (P<0.05) to the estimation of leg, midloin, forequarter, and shank cuts. In all cases the coefficient was positive, indicating that increases in EMA would lead, at constant carcass weight and fatness (GR), to an increase in the proportion of these cuts in the carcass. The amount of variation (R2) explained for the individual trim cuts ranged from 0.08 to 0.72 using models that included independent variables HCW, GR, and EMA, and which accounted for the effect of sex. For traditional cuts the values ranged from 0.28 to 0.79.

The area of eye muscle of beef cattle carcasses

1963 ◽  
Vol 3 (10) ◽  
pp. 249
Author(s):  
RM Seebeck
Keyword(s):  
Beef Cattle ◽  
Cross Sectional Area ◽  
Carcass Weight ◽  
Sectional Area ◽  
Muscle Area ◽  
Cross Sectional ◽  
Eye Muscle ◽  
Angus Cattle ◽  
The Cross

Variations in the cross-sectional area of eye muscle of carcasses cut between the tenth and eleventh ribs were investigated, using 105 Hereford and 51 Angus steers aged 20 months. These cattle consisted of three groups, born in successive years. At constant carcass weight, statistically significant differences in eye muscle area were found between breeds and between years. Breed and year differences were also found in eye muscle area with width and depth of eye muscle constant, so that there are limitations to the estimation of eye muscle area from width and depth measurements. A nomograph is given for estimating eye muscle area from width and depth for Hereford and Angus cattle, when all animals are reared in the same year and environment. The use of eye muscle area as an indicator of weight of carcass muscle is discussed.

An evaluation of the Hennessy and Chong Fat Depth Indicator, and the Ulster Probe, for use in pig carcass classification and grading

1981 ◽  
Vol 33 (3) ◽  
pp. 319-324 ◽  
Author(s):  
A. J. Kempster ◽  
J. P. Chadwick ◽  
D. W. Jones ◽  
A. Cuthbertson
Keyword(s):  
Standard Deviation ◽  
Multiple Regression ◽  
Lumbar Vertebrae ◽  
Optical Probe ◽  
Carcass Weight ◽  
Residual Standard Deviation ◽  
Fat Thickness ◽  
Prediction Residual ◽  
Thickness Measurements ◽  
Cut Surface

ABSTRACTThe Hennessy and Chong Fat Depth Indicator and the Ulster Probe automatic recording instruments developed for measuring fat thickness were tested against the optical probe for use in pig carcass classification and grading.Fat thickness measurements were taken using each probe 60 mm from the dorsal mid-line over the m. longissimus at the positions of the 3rd/4th lumbar vertebrae, 3rd/4th last ribs and last rib on a total of 110 hot carcasses covering the range of market weights in Great Britain. The standard deviation of carcass lean proportion at equal carcass weight was 35·4 g/kg.The instruments differed little in the precision of carcass lean proportion prediction: residual standard deviation (g/kg) for the multiple regression with carcass weight and the best individual fat measurement for each probe were: last rib optical probe, 22·1; last rib Ulster Probe, 22·7; and 3rd/4th last rib Fat Depth Indicator, 21/6. Residual standard deviation (g/kg) for carcass lean proportion prediction from carcass weight and all three fat measurements in multiple regression were 21·3 optical probe, 21·3 Ulster Probe and 201 Fat Depth Indicator.Similar mean fat measurements were obtained from the optical probe and Fat Depth Indicator, and for these instruments, but to a lesser extent for the Ulster Probe, the regression relationships with each other and with fat thickness measurements taken on the cut surface of the cold carcass were also similar.The differences recorded in precision are unlikely to be sufficiently important to influence the choice of one probe rather than another.

Selection for efficient lean growth in a pig herd

1981 ◽  
Vol 32 (4) ◽  
pp. 681 ◽  
Author(s):  
CP McPhee
Keyword(s):  
Growth Rate ◽  
Food Intake ◽  
Performance Test ◽  
Subcutaneous Fat ◽  
Performance Testing ◽  
Restricted Feeding ◽  
Food Conversion ◽  
Muscle Area ◽  
Eye Muscle ◽  
Lean Growth

A pig herd was selected for 6 years by using an economic index combining growth rate, food conversion efficiency and carcass leanness. These three traits were all measured in a performance test which permitted appetite variation between pigs to be expressed. Boars selected with an intensity of 118 were used for 6 months, and sows with an intensity of 114 were kept for two farrowings. An unselected control herd was maintained concurrently. To measure selection response, selected (S) and control (C) pigs were compared as they grew from 25 to 90 kg liveweight on ad lib. and restricted feeding during the last 2 years of selection. The following significant (P < 0.05) responses occurred in the selection herd: (i) A slight increase in growth rate on restricted feed, balanced by a similar decrease on ad lib, feeding. (ii) A decline in food conversion ratio of 5 % (C, 2.79; S, 2.65) due mainly to a reduction in appetite. (On ad lib. feeding, food intake per day declined by 6 % (C, 2.30 kg/d; S, 2.16 kg/d.)). (iii) A decline in average subcutaneous fat depth by 11 % (C, 27.8 mm; S, 24.7 mm) and in fat dissected from the ham by 7 % (C, 2.80 kg; S, 2.61 kg). (iv) An increase in estimated lean in the carcass by 2% (C, 30.3 kg; S, 31.0 kg). (v) A decline in dressing percentage of the carcass by 1 % (C, 77.1 %; S, 76.2 %). There was no change in eye muscle area or carcass length. The results are discussed in terms of changes in the ratio of food intake to lean growth. In the group fed ad lib., this ratio declined by 7 %, mainly because of a decline in food intake. On restricted feeding it fell by 6 %, mainly owing to an increase in lean growth. That portion of the selection effort absorbed in reducing food intake may have been more profitably directed to increasing lean growth by suppressing appetite variation during performance testing, rather than allowing it to be expressed.

Genetic parameters for terminal sires estimated using data of progeny from Border Leicester × Merino ewes

1995 ◽  
Vol 46 (4) ◽  
pp. 703
Author(s):  
PA Kenney ◽  
ME Goddard ◽  
LP Thatcher
Keyword(s):  
Genetic Parameters ◽  
Selection Index ◽  
Genetic Correlations ◽  
Subcutaneous Fat ◽  
Muscle Area ◽  
Eye Muscle ◽  
Bone Length ◽  
Selection For ◽  
Using Data ◽  
Omental Fat

Three and a half thousand lambs from Border Leicester x Merino ewes mated to 133 sires from five Poll Dorset, one White Suffolk, one Siromt, two Meridale and four Merino studs were slaughtered, their carcasses halved and one side divided into six primals. Subcutaneous fat was dissected from all six primals, and bone from only the three rear primals. There were four slaughter groups: average slaughter weights of 30 and 35 kg for ewes and 35 and 45 kg for cryptorchids. Heritabilities and phenotypic and genetic correlations for all traits measured (>50) are published in an appendix. Where comparisons were available, estimates were similar to those for purebred animals. Genetic parameters for various assessments of fat were similar except for channel and omental fat. The GR fat depth was the best predictor for total subcutaneous fat, cannon bone length for total bone, and eye muscle area for total soft tissue. Carcass weight and GR appear to be the most important measurements for use in selection for breeding of sires for the prime lamb industry. Slaughter weight and fat depth at the C site could be used as suitable alternatives on live animals. Production of lean meat is not likely to be increased greatly by including measurements other than liveweight and GR in a selection index. Of the other measurements bone length and eye muscle measurements showed most promise.

scholarly journals Response in nutritionally related blood metabolites, carcass traits and primal pork cuts of slow growing Windsnyer pigs fed on varying levels of potato hash silage

1970 ◽  
Vol 48 (4) ◽  
pp. 770-776
Author(s):  
C.N. Ncobela ◽  
A.T. Kanengoni ◽  
M. Chimonyo
Keyword(s):  
Alkaline Phosphatase ◽  
Linear Relationship ◽  
Total Protein ◽  
Linear Response ◽  
Carcass Traits ◽  
Carcass Weight ◽  
Muscle Area ◽  
Eye Muscle ◽  
Inclusion Level ◽  
Quadratic Relationship

The response of Windsnyer pigs to diets containing varying levels of potato hash silage in nutritionally related blood biochemistry, carcass traits and primal pork was estimated. Thirty-six growing clinically healthy male Windsnyer pigs with an initial weight of 36 kg ± 4.89 (mean ± standard deviation (SD)) were randomly assigned to six experimental diets containing 0, 80, 160, 240, 320, and 400 potato hash silage g/kg dry matter (DM). Experimental diets were derived from mixing a summit diet containing no potato hash silage and a dilution diet containing 400 g potato hash silage/kg in various proportions. Pigs were allowed ad libitum access to diets and water. There was no relationship between inclusion levels of potato hash silage and albumin: globulin ratio, total protein, and uric acid. As inclusion levels of potato hash silage varied, there was a positive linear relationship between silage and albumin concentration. Globulin concentration had a positive quadratic relationship with the inclusion of potato hash silage. Inclusion levels of potato hash silage resulted in a positive quadratic relationship in alkaline phosphatase. There was a negative linear response in warm carcass weight and cold carcass weight to inclusion levels of silage. A negative linear response was observed in dressing percentage. Different inclusion levels of potato hash silage caused a positive quadratic relationship in cooler shrink. There were negative linear relationships between inclusion of potato hash silage with shoulder fat, carcass length and backfat thickness. There was a negative linear relationship between eye muscle area and inclusion level of ensiled potato hash. There was a positive quadratic relationship between hindquarter length (HQL) and inclusion levels of silage. The observed linear relationship between hindquarter circumference (HQC) and inclusion levels of potato hash silage was negative. There is a need to predict the optimum inclusion level of potato hash silage without compromising the healthiness and carcass yield of pigs.Keywords: Alkaline phosphatase, backfat thickness, cold carcass weight, cooler shrink, dorsal fat thickness, eye muscle area, hindquarter circumference, total protein

Sign in / Sign up

Export Citation Format

Share Document