Investigations into the accuracy of prediction of beef carcass composition using subcutaneous fat thickness and carcass weight I. Identifying problems

Meat Science ◽  
1997 ◽  
Vol 46 (2) ◽  
pp. 147-157 ◽  
Author(s):  
R. Priyanto ◽  
E.R. Johnson ◽  
D.G. Taylor
1984 ◽  
Vol 102 (3) ◽  
pp. 511-516 ◽  
Author(s):  
E. R. Johnson ◽  
M. K. Vidyadaran

SummaryIndividual muscles, individual bones and fat depots from the non-carcass parts (head, foreshanks and tail) of 40 steers (chilled carcass weight 142–174 kg) were studied in an attempt to predict carcass composition more accurately than in an earlier study where the crude non-carcass parts, head, tongue, foreshanks and hindshanks were used.The technique did not improve the accuracy of prediction of muscle or bone. Carcass fat, which was calculated by difference in the earlier study, was predicted more accurately using intermandibular fat weight (requiring 3–4 min to obtain) plus fat thickness at the 12th rib. However, the accuracy of this prediction (carcass fatness range 14·0–33·6%, residual standard deviation 1·98%) was no greater than that using chilled side weight plus fat thickness at the 12th rib.Careful dissection and trimming of anatomical entities from the non-carcass parts therefore offered a slight advantage only in the prediction of carcass components over existing techniques.Substitution of hot side weight for chilled side weight, and sacral crest fat thickness for fat thickness at the 12th rib did not lead to a loss in the accuracy of prediction of muscle, bone or fat.


1982 ◽  
Vol 62 (2) ◽  
pp. 645-648 ◽  
Author(s):  
S. D. M. JONES ◽  
C. R. HAWORTH

Left sides from 360 cold beef carcasses were probed at the 11th rib site for fat thickness at three positions (1/4, 1/2 and 3/4 positions). Each probe measurement was repeated and the fat thickness at the three sites was then measured using a ruler. Comparison of probe readings with ruler measures showed that the probe consistantly overpredicted fat thickness by margins ranging from 3 to 8 mm (P < 0.001). Regression of probe readings on ruler measures showed that only in the 1/4 position was the slope not different (P > 0.05) from unity. Regression of the first probe reading on the repeated reading also showed that the slope for the 1/4 position was not different (P > 0.05) from unity. Key words: Beef, carcass grading, fat thickness, FDI


2018 ◽  
Vol 39 (6) ◽  
pp. 2717
Author(s):  
Leandro Lunardini Cardoso ◽  
Joal José Brazzale Leal ◽  
Marcelo Henrique Giordano Nunes ◽  
Bruno Borges Machado Teixeira ◽  
Bruna Pena Sollero ◽  
...  

This paper aimed to identify and evaluate the effects of sire breed on temperament and productive traits of different cross-breeds between Nellore (NE), Tabapua (TB), and Brahman (BR) bulls mated with Angus cows (AN), as well as the relationship between temperament and productive traits. The productive traits measured in this study include slaughter weight and post weaning weight gain. Temperament was assessed by flight-speed (FS). Carcass data collected in this study include hot carcass weight, hot carcass percentage, cold dressing percentage, carcass length, initial pH, ultimate pH, subcutaneous fat thickness and carcass longissimus muscle area. The sire breed effect was greater for slaughter weight. Hot carcass weight was not affected by the sire breed. The longissimus muscle area was larger for AN x TB and AN x NE crossbreeds than for AN x BR crossbreeds. Subcutaneous fat thickness and cold dressing percentage were not affected by sire breed. The offspring of NE, TB, and BR sires mated with AN cows had similar carcass measurements, except for the longissimus muscle area, which was smaller for offspring sired by the Brahman breed. The temperament trait was not influenced by sire breed.


2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 422-423
Author(s):  
Janaina S Biava ◽  
Nathalia R Eckermann ◽  
Thamires U Sturion ◽  
Daniel M Polizel ◽  
Paulo Dias Junior ◽  
...  

Abstract The objectives of this trial were to evaluate the effects of levels of fiber in high-grain diets on carcass characteristics of feedlot lambs. Fifty-eight Dorper x Santa Inês ram lambs (initial BW 20.7 ± 1.19 kg and 75 ± 10.83 d old) were assigned to a randomized complete block design. The treatments were defined by the fiber (“Coastcross” hay) content in the diets (CP: 16,12% ± 0.92): 0F: no forage diet (NDF: 10.4%); 5F: 5% of forage (NDF: 12.1%); 10F: 10% of forage (NDF: 15.0%); 15F: 15% of forage (NDF: 15.5%); 20F: 20% of forage (NDF: 20.8%) and 25F: 25% of forage (NDF: 23.5%). The experiment lasted 89 days, at the end of this time, the animals were slaughtered (169 ± 10.83 d old) to evaluate carcass characteristics. There was a quadratic response for slaughter BW (0F: 46.3; 5F: 48.1; 10F: 49.4; 15F: 50.3; 20F: 48.5; 25F: 43.3 kg; P &lt; 0.01), hot carcass weight (0F: 24.8; 5F: 25.6; 10F: 26.0; 15F: 25.7; 20F: 24.3; 25F: 21.8 kg; P = 0.01), cold carcass weight (0F: 24.3; 5F: 25.1; 10F: 25.4; 15F: 25.1; 20F: 23.8; 25F: 21.2 kg; P = 0.01) and longissimus dorsis area (0F: 16.3; 5F: 16.5; 10F: 17.4; 15F: 16.5; 20F: 16.0; 25F: 15.1 cm2; P = 0.04). There was a linear decrease in the hot carcass yield (0F: 53.0; 5F: 53.3; 10F: 52.5; 15F: 50.9; 20F: 50.1; 25F: 50.2%; P &lt; 0.01), cold carcass yield (0F: 52.0; 5F: 52.2; 10F: 51.4; 15F: 49.8; 20F: 49.0; 25F: 48.9%; P &lt; 0.01) and body wall thickness (0F: 16.2; 5F: 17.0; 10F: 16.3; 15F: 16.3; 20F: 15.1; 25F: 13.6 kg; P = 0.01). There was no effect on subcutaneous fat thickness. In conclusion, the diet with up to 5% of forage allowed higher carcass yield; however, the heavier carcasses were produced by the lambs that received 10F diet.


1967 ◽  
Vol 68 (2) ◽  
pp. 301-306 ◽  
Author(s):  
H. J. Tuma ◽  
C. A. Dinkel ◽  
J. A. Minyard ◽  
B. C. Breidenstein

Various carcass measurements were obtained from 216 Hereford steers and evaluated in an attempt to find traits or combinations of traits which accurately estimate carcass composition. Carcass weight and trimmed retail cuts from the round proved to be the best single estimators of kilograms of retail cuts. Prediction equations were developed using carcass weight, trimmed retail cuts from the round, longissimus dorsi area, measures of fat thickness at the 12th rib, untrimmed round weight and weight of kidney, heart and pelvic fat in various combinations. Eighty-four to 94 % of the total variation in actual kilograms of retail cuts could be accounted for by using these equations.


1982 ◽  
Vol 62 (2) ◽  
pp. 371-379 ◽  
Author(s):  
S. D. M. JONES ◽  
J. S. WALTON ◽  
J. W. WILTON ◽  
J. E. SZKOTNICKI

Thirty-eight lambs (22 rams, 16 ewes), 25 Holstein cows and 30 steers were evaluated ultrasonically for subcutaneous fat thickness. Urea space was also estimated, using the dilution principle, by a single injection of a known amount of urea and taking a single blood sample 12 min later. All lambs and cattle were slaughtered within 2 days and the half-carcasses were separated into fat, lean and bone. Urea space (R2 = 0.10) and fat thickness (R2 = 0.18) in lambs were poorly related to the weight of half-carcass lean tissue. Neither urea space nor fat thickness improved the level of explained variation in half-carcass lean tissue weight over that explained by liveweight alone (R2 = 0.73). Urea space showed a larger association with half carcass lean weight in cows (R2 = 0.55) than in steers (R2 = 0.14), but again did not improve the relationship provided by liveweight alone (R2 = 0.60). Fat thickness provided nonsignificant regressions (P < 0.05) with half-carcass lean weight both in cows and in steers. Liveweight was the dominant independent variable (R2 = 0.33) for predicting total fat in lamb half-carcasses; urea space (R2 = 0.08) and fat thickness (R2 = 0.13) did not improve the prediction given by liveweight alone. Fat thickness was poorly related to total fatness both in steers (R2 = 0.12) and in cows (nonsignificant regression). A multiple regression equation combining fat thickness and liveweight provided the best prediction of half-carcass fat in cows, whereas a similar equation with the addition of urea space gave the best prediction of half-carcass fat in steers. The measurement of urea space and fat thickness to predict the weight of carcass tissues (lean, fat) in live lambs and cattle over the weight (41.9 + 9.7 kg(SD) lambs, 624 ± 62.8 kg cows and 466 ± 63.2 kg steers) and fatness (19.9 ± 3.27% (SD) lambs, 21.9 ± 2.18% cows and 20.9 ± 3.98% steers) ranges studied was of limited value. Key words: Urea dilution, ultrasound, live animal evaluation, carcass composition


1994 ◽  
Vol 34 (4) ◽  
pp. 435 ◽  
Author(s):  
ER Johnson

Predictions of carcass composition based on anal fold and 12th rib fat thickness measurements were compared in 12 Hereford heifers and 12 Hereford steers. For carcass proportions, simple regression equations indicated that heifers had less muscle (2-3%), more fat (2.5-4%), and more bone (0.9%, 12th rib only). Empty liveweight did not improve the accuracy of prediction of any carcass component when added to anal fold fat thickness. Chilled carcass weight and 12th rib fat thickness slightly improved the accuracy of prediction of muscle and fat proportions compared with prediction using each measurement alone. Multiple regression indicated that the heifers had 2.5-3% less muscle and 34% more fat. For predictions of the weights of carcass components at a given fat thickness measurement, simple regression indicated that heifers had less muscle than steers (by about 6 kg), but for bone and fat the intercepts did not differ significantly between sexes. In multiple regression, empty liveweight contributed strongly to the predictions of weights of all 3 carcass components. In all regressions in which the weight of each of the 3 carcass components was regressed on a weight and a fat thickness measurement together, except for muscle and fat regressed on chilled carcass weight and 12th rib fat thickness, the fat thickness measurement failed to contribute significantly to prediction. Although chilled carcass weight and 12th rib fat thickness together contributed (P<0.01) to the prediction of muscle weight and fat weight, chilled carcass weight was the stronger contributor. Regression indicated that heifers had about 3 kg less muscle and 3.5 kg more fat than steers. Multiple regression analysis showed that heifers and steers had about the same weight of bone.


2017 ◽  
Vol 8 (s1) ◽  
pp. s22-s27 ◽  
Author(s):  
M. Al-Jammas ◽  
J. Agabriel ◽  
J. Vernet ◽  
I. Ortigues-Marty

In cattle, the chemical composition of the carcass is usually evaluated from one of three reference methods (rib dissection, specific gravity or a combination of easily obtained measures) or is estimated from proxy traits (USDA yield grade (YG), subcutaneous fat thickness (SFT)). Objectives were to evaluate if the relationships between the chemical composition of the carcass and each of the proxy traits (YG, SFT) differed depending on the reference method. The study was conducted by meta-analysis from published results using 25 publications that reported carcass composition and proxy traits (53%, 31% and 16% of the data were based on rib dissection, specific gravity and combination of easily obtained measures, respectively). Results showed that the amounts of carcass fat or protein that can be predicted from a given proxy trait (YG or SFT) differ significantly with the reference method used to determine carcass fat or protein.


1969 ◽  
Vol 81 (3-4) ◽  
pp. 115-124
Author(s):  
Américo Casas ◽  
Danilo Cianzio ◽  
Aixa Rivera

After two complete grazing trials, 47 Holstein, Charbray and Zebu (mostly Brahman) bulls were processed for offal components, carcass traits and composition comparisons at an average liveweight (LW) of 545 kg. At the same LW the Holstein bulls had a significantly higher (P < 0.05) weight for the head (3.33% of LW), feet (2.47% of LW), liver (1.11% of LW), kidneys (1.29% of LW) and intestines (5.18% LW) than the Zebu and Charbray bulls, and a significantly longer leg (53.0 vs. 48.90 cm; P < 0.05) than the Charbray bulls. The Zebu bulls had the heaviest hide (P < 0.05) and smallest stomach weight (P < 0.05). The carcasses of the Holstein bulls had a significantly higher (P < 0.05) bone percentage (21.60 vs. 16.63, 17.46%) and a lower amount of fat than the Charbray and Zebu bulls, respectively. Charbray bulls presented greater loin eye area, total amount of muscle, muscle to bone+fat ratio and weight and percentage of the Biceps femoris, Gluteus, and Cuadriceps femoris muscles in the left-hindquarter (LH), than the Zebu and Holstein bulls (P < 0.05). Charbray and Zebu bulls showed greater (P < 0.05) thickness of the round (26.03, 25.85, vs. 24.03 cm), hot carcass and LH weight, total dissectible fat, dressing percentage, muscle to bone ratio, and weight of the Semimembranosus, Psoas major, Longissimus dorsi and Semitendinosus muscles than the Holstein bulls (P < 0.05). No significant differences (P > 0.05) were found among breeds for subcutaneous fat thickness and for the weights of fascia/tendon, trimming, carcass shrinkage, and for the forequarter weight and percentage of left side.


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