EFFECT OF HIGH CONCENTRATE FEEDING ON THE CARCASS QUALITY AND FAT COLORATION OF GRASS-REARED STEERS

1981 ◽  
Vol 61 (3) ◽  
pp. 575-580 ◽  
Author(s):  
R. J. FORREST

Fifty yearling beef steers of primarily mixed British beef breeding, and averaging 237.8 kg (SD = 23.47) were reared on grass from April to October. They were then placed in a feedlot for finishing and serially slaughtered over a 112-day feeding period. Feedlot gains averaged 0.64 kg/day, while carcass weight increased from 380.8 to 450.2 kg and rib fat increased from 18.7 to 30.8%. After 56 days in the feedlot, all carcasses graded either A-1 or A-2. After 28 days, the amber fat color, as scored by Federal Government graders, had been reduced from 6.5 to 4.5 when rated on a scale ranging from 1 (white) to 9 (intense amber). Carotene analysis of the carcass fat demonstrated a significant reduction (P < 0.05) from 0.28 to 0.17 mg/100 g fat during the first 28-day feeding period. These findings indicate that yearling steers reared on grass and not carrying an excessive amount of subcutaneous fat can produce A-1 carcasses, with acceptable coloration, after a concentrate feedlot finishing period of 56 days.

1993 ◽  
Vol 33 (6) ◽  
pp. 685 ◽  
Author(s):  
DL Hopkins ◽  
AHK Roberts

Fifty-six carcasses from grass-fed steers of 4 breed types, purchased for the Japanese market, were evaluated for quality and yield characteristics. The mean (� s.d.) carcass weight was 324 � 28.3 kg, and P8 fat depth 16.5 � 5.27 mm. Based on the Japanese grading system. 52 of the carcasses were considered acceptable for marbling, 54 for fat colour, and all carcasses for meat colour. The mean marbling, fat colour, and meat colour scores were 3.3, 3.3, and 3.5 respectively. The rank correlation between P8 fat depth and marbling score was 0.09, and a similar level of association was found between marbling score and fat depth measurements at other positions on the carcass. Measures of M. longissimus thoracis et lumborum (LD) area, using different techniques at the same rib, were significantly (P<0.001) correlated (5th rib, r = 0.87; 10th rib, r = 0.80); however, there was no association between LD area at the 5th and 10th ribs. Models were developed to predict the weight of saleable meat (SM) and fat trim (FT) based initially on hot standard carcass weight (HCW) and P8 fat depth as the independent variables. For all models HCW was the important predictor, with various measures of subcutaneous fat depth increasing the accuracy of estimates by a small amount. Fat depth measurements from the loin region reduced the error of prediction of SM more than fat depth measurements from the rump region, irrespective of the method used to measure fat depth. Replacing fat depth measures with the weight of trimmed fat significantly improved the accuracy of the predictions. The best model for predicting FT weight was based on the predictors HCW and fat depth at the 12th113th rib. Breed type was found to be not significant (P = 0.07) if included in a model with P8 fat depth and HCW. When breed type was included, P8 fat depth was no longer significant. When LD area at the 10th rib was included with HCW and P8 fat depth as a predictor of SM, P8 fat depth was no longer significant (P>0.05), but this was not the case when estimates of LD at the 5th rib were used. Regardless of this, estimates of LD area at both ribs showed themselves to be useful predictors of SM additional to HCW and P8 fat depth. Breed type was not a significant (P>0.05) contributor to the model based on the predictors HCW, P8 fat depth, and LD area at the 10th rib. If fat depth at the 10th rib was used with HCW and LD at the 10th rib instead of P8 fat depth, then more of the variation (R2 = 0.88 v. 0.85) in SM was explained and the error of the prediction was less (3.34 v. 3.75). Also, when fat depth at the 10th rib was used, the rib site used to estimate LD area was less important. The models showed that prediction of SM in heavyweight carcasses was marginally aided by using estimates of LD area.


2012 ◽  
Vol 52 (9) ◽  
pp. 823 ◽  
Author(s):  
M. Blanco ◽  
M. Joy ◽  
B. Panea ◽  
P. Albertí ◽  
G. Ripoll ◽  
...  

Eighteen Parda de Montaña steers (366 kg liveweight, 10 months of age) received diets of either forage (F; lucerne hay + straw) or forage and concentrate (FC; lucerne hay + straw + barley) during the winter feeding period, which lasted 118 days. Thereafter, steers continuously grazed in meadows in a dry mountain area until the end of the grazing period in September (160–167 days) and received 4.1 kg DM barley per head for the final 103–110 days of the grazing season. The steers that received the FC winter diet were heavier (491 vs 457 kg, respectively; P < 0.05) and had deposited more fat (7.2 vs 5.8 mm, P < 0.05) and muscle (63 vs 54 mm, P < 0.05) at the end of the winter than the steers that received the F winter diet. During the grazing period, the steers from both groups had similar weight gains (0.728 and 0.756 kg/day for FC and F diet, respectively). At slaughter, the steers from both groups were of similar age (590 vs 599 days, for FC and F diet, respectively) and had similar liveweights (560 vs 539 kg), muscle depths (54 vs 63 mm) and subcutaneous fat thicknesses (7.3 vs 7.2 mm). The serum leptin concentration differed only at the end of the winter period, when steers on the FC diet had higher leptin concentrations than did steers on the F diet (P < 0.05), reflecting differences in fatness. The carotenoid concentration in the plasma during the winter feeding period was higher in steers on the F than on the FC winter diet, but this difference was not seen during the grazing period. Carcasses from steers on the FC winter diet were heavier (324 vs 300 kg; P < 0.05) and had a higher dressing percentage (57.3% vs 56.1%, P < 0.05) than those reared on the F winter diet, but the fatness and conformation scores were similar between the groups. The percentages of fat, muscle and bone in the commercial dissection and 10th rib dissection did not differ between the winter diet groups. In conclusion, the differences resulting from the winter feeding period disappeared after the grazing period, and the carcass quality did not differ between the diets. Therefore, both strategies are equally technically advisable.


Author(s):  
P J Rincker ◽  
J B Allen ◽  
M Edmonds ◽  
M S Brown ◽  
J C Kube

Abstract There is a lack of consistency across the globe in how countries establish tissue ractopamine residue limits and which residue limits are applied to various tissues, particularly for edible noncarcass tissues. Therefore, some US beef slaughter organizations have recommended a 48-h voluntary removal of ractopamine before slaughter in order to meet residue requirements of specific export countries and maintain international trade. Our objective was to assess the impact of voluntary removal of ractopamine hydrochloride (Optaflexx®; Elanco, Greenfield, IN) up to 8 d before slaughter on growth performance and carcass characteristics. Crossbred beef steers (60 pens of 10 animals/pen) with an initial shrunk body weight (BW) of 611.8 ± 10 kg SEM were fed one of six treatments over 42 d. Treatments included a control that did not receive ractopamine, on-label use of ractopamine (0-d withdrawal), and 2, 4, 6, or 8 d of voluntary removal of ractopamine from feed before slaughter. The start of ractopamine feeding (30.1 mg/kg of diet dry matter for 32 d) was staggered so that blocks could be slaughtered on the same day. Dry matter intake was decreased by 0.5 kg/d when ractopamine was fed with a 0-d withdrawal (P = 0.04) compared to the control, but was not altered (P = 0.56) as the duration of ractopamine removal increased from 0 to 8 d. Final BW, total BW gain, and average daily BW gain were increased by feeding ractopamine with a 0-d withdrawal (P = 0.09) compared to the control, but these variables decreased in a linear manner (P = 0.10) as the duration of removal increased from 0 to 8 d. Gain efficiency was improved by 15% (P &lt; 0.01) by feeding ractopamine with a 0-d withdrawal compared to the control, and gain efficiency decreased linearly (P = 0.06) as the duration of ractopamine removal increased. Approximately 2/3 of the increase in gain efficiency remained after 8 d of removal. Hot carcass weight was increased by 6 kg (P = 0.02) by feeding ractopamine with a 0-d withdrawal compared to the control. Measured carcass characteristics were not altered by ractopamine feeding or by removal before slaughter (P ≥ 0.24). The consequences of voluntary removal of ractopamine up to 8 d before slaughter were a linear decrease in live BW gain (0.64 kg/d), poorer gain efficiency, and numerically lighter carcass weight.


2021 ◽  
pp. 104694
Author(s):  
Francisco Fernandes Junior ◽  
Amanda de Freitas Pena ◽  
Fernando Augusto Grandis ◽  
Natalia Albieri Koritiaki ◽  
Fabíola Cristine de Almeida Rego ◽  
...  

1984 ◽  
Vol 64 (1) ◽  
pp. 53-57 ◽  
Author(s):  
S. D. M. JONES ◽  
R. E. ROMPALA ◽  
J. W. WILTON ◽  
C. H. WATSON

Empty body weights, carcass weights and offal proportions were compared in 33 young beef bulls and 33 beef steers of different mature body size (35 small or mainly British breed crosses, 31 large or Continental crosses). All cattle were fed a high energy diet based on corn silage and high moisture corn from weaning to slaughter. Slaughter was carried out once 6 mm of fat had been attained at the 11/12th ribs, determined ultrasonically. Feed was removed 24 h and water 16 h prior to slaughter. The offal components were all weighed fresh and the alimentary components emptied of digesta. Bulls weighed 8.0% heavier (P < 0.05) than steers at slaughter, while large animals were 38.7% heavier (P < 0.0001) than small animals. Bulls and large animals had carcasses that dressed out 1.5% heavier than steers and small animals. To eliminate the effect of gutfill, carcass weights and offal components were expressed as a proportion of empty body weight. Bulls had a higher proportion of warm carcass weight and lower proportions of liver, spleen, heart, lungs, rumen, abomasum, large intestine and front feet relative to empty body weight than steers. Large animals had a greater proportion of warm carcass weight and hind feet, and a lower proportion of head, hide, liver, kidneys, omasum and small intestine relative to empty body weight than small animals. All castration by size interactions for liveweight, carcass weight, empty body weight and offal proportions were not significant. Castration and small animal size both increased the proportion of noncarcass parts relative to empty body weight in animals slaughtered at similar finish. Key words: Body, carcass, offal, bull, steer, maturity


1979 ◽  
Vol 30 (6) ◽  
pp. 1207 ◽  
Author(s):  
JM Thompson ◽  
KD Atkins ◽  
AR Gilmour

Half-carcasses of 108 wether and ewe lambs from six genotypes, slaughtered at 34, 44 and 54 kg liveweight, were dissected into subcutaneous fat, intermuscular fat, muscle, bone and connective tissue. The six genotypes were the progeny of Dorset Horn and Border Leicester rams mated to Merino, Corriedale and Border Leicester x Merino first-cross ewes. As carcass weight increased, the proportion of subcutaneous and intermuscular fat increased (b > 1 ; P < 0.05) and the proportion of muscle and bone decreased (b < 1; P < 0.05). Lambs sired by Border Leicester rams had more subcutaneous fat (12.7%), more intermuscular fat (7.6%) and more bone (5.7%) than lambs sired by Dorset Horn rams at the same carcass weight (P< 0.05). Similarly, lambs sired by Dorset Horn rams had more muscle (7.2%) than lambs sired by Border Leicester rams at the same carcass weight (P < 0.05). Breed of dam had no effect on carcass composition. Wether lambs had a greater proportion of bone (5.7%) than ewe lambs at the same carcass weight (P < 0.05). The breed of sire effect and the lack of a breed of dam effect on carcass composition, in conjunction with estimated mature weights for the breeds, suggest possible differences between sire and dam breeds in the partitioning of fat between the carcass and non-carcass depots. ____________________ *Part I, Aust. J. Agric. Res., 30: 1197 (1979).


1995 ◽  
Vol 73 (10) ◽  
pp. 2971 ◽  
Author(s):  
R D Sainz ◽  
F De la Torre ◽  
J W Oltjen

1972 ◽  
Vol 15 (3) ◽  
pp. 229-237
Author(s):  
C. E. Hinks ◽  
J. H. D. Prescott

SUMMARYTwo experiments concerning the effects, on the carcass and meat characteristics of 18-months-old Friesian steers, of variation in grazing intensity and the level of barley feeding with silage are reported.Groups of 12 steers were grazed at different intensities over 5-month grazing periods, such that live-weight differences of 38 kg and 16 kg were recorded at housing. No compensatory growth was recorded during the subsequent winter feeding period.Whilst the grazing treatments had little effect on carcass or meat quality, higher levels of barley feeding with silage over the winter period (710 v. 410 kg/steer) had significant effects on live-weight gain, and increased carcass weight by 21 kg at slaughter. The higher yield of carcass weight was reflected in significant differences in carcass composition, joint proportions and retail cut-out value. Sixty per cent of the carcass weight difference was removed as trim fat. Differences in carcass fatness were not associated with any differences in eating quality.


1999 ◽  
Vol 69 (1) ◽  
pp. 81-92 ◽  
Author(s):  
A. F. Carson ◽  
B. W. Moss ◽  
R. W. J. Steen ◽  
D. J. Kilpatrick

AbstractThis study investigated the effects of the percentage of Texel or Rouge de l’Ouest (Rouge) genes in lambs (0, 50, 75 or 100%; the remainder being Greyface (Border Leicester × Scottish Blackface)) on lamb carcass characteristics and meat quality. Ewe lambs were slaughtered at 34, 40, 46 and 52 kg and ram lambs were slaughtered at 40, 46, 52 and 58 kg live weight. Dressing proportion increased (P < 0·001) by 0·53 and 0·27 g carcass weight per kg live weight for each 1% increase in Texel or Rouge genes respectively. Carcass conformation classification increased (P < 0·001) by 0·016 and 0·007 units (on a five-point scale) for each 1% increase in Texel or Rouge genes respectively. Carcass fat depth measures were reduced by Texel and Rouge genes such that at a constant fat depth end point, carcass weight could be increased by 0·029 and 0·023 kg for each 1% increase in Texel or Rouge genes. Carcass lean content increased (P < 0·001) by 0·99 and 0·27 g/kg for each 1% increase in Texel or Rouge genes. Subcutaneous fat content was reduced (P < 0·001) by 0·36 and 0·29 g/kg for each 1% increase in Texel or Rouge genes. Intermuscular fat content was reduced (P < 0·01) by 0·38 g/kg per 1% increase in Texel genes, whereas Rouge genes had no effect. Similarly, bone content was reduced (P < 0·01) by Texel genes only (0·31 g/kg per 1% increase in Texel genes). Warner-Bratzler shear force values showed a quadratic effect with increasing Texel and Rouge genes, with an initial decrease from 0 to 50% followed by an increase to 100%. Cooking loss increased (P = 0·05) as the percentage of Rouge genes in lambs increased. Increasing the percentage of Texel or Rouge genes significantly increased L* values (P < 0·01 and P < 0·05 respectively), b* values (P = 0·05 and P< 0·05 respectively) and H° values (P < 0·001).


1980 ◽  
Vol 30 (1) ◽  
pp. 135-152 ◽  
Author(s):  
J. D. Wood ◽  
H. J. H. MacFie ◽  
R. W. Pomeroy ◽  
D. J. Twinn

ABSTRACTIn order to investigate the effects of type of breed on carcass composition, an examination was made of 361 lambs from four breeds: Clun Forest and Colbred (termed ewe breeds); and Suffolk and Hampshire (termed ram breeds). The animals were in four carcass weight groups averaging 15, 17, 19 and 21 kg.Percentage subcutaneous fat was influenced more by carcass weight than by breed, whereas both carcass weight and breed had similar effects on percentage lean. At the mean carcass weight of 18 kg, Colbreds, the leanest breed, had a similar value for percentage lean (about 57 % of carcass tissue weight) to the carcasses over all breeds weighing 15 kg; and Cluns, the fattest breed, had a similar value (about 54%) to those weighing 21 kg. Since the ram breeds were intermediate in composition between the two ewe breeds there was no effect of type of breed on carcass composition. The breed differences were related to eventual mature size and to the stage of maturity at each carcass weight, as judged by body length and bone weight measurements. However, Colbreds were bigger and leaner than published estimates of their mature weight suggested. Humerus weight was a good predictor of lean or total fat weight, explaining 83 % ofvariation when used as a predictor along with carcass weight.Type of breed had a marked effect on internal fat deposition, the ewe breeds having heavier weights of both kidney knob and channel fat (KKCF) and caul fat (omental fat) than the ram breeds; and on the length oflimb bones, the ewe breeds having longer but thinner bones than the ram breeds. The order of the relative growth of the tissues and fat depots was: subcutaneous fat > caul fat > KKCF > intermuscular fat > lean > bone. Therefore, the internal fat depots were later maturing than intermuscular fat.The percentage of prime cuts in the carcass was not affected by carcass weight. Colbreds had significantly lower values than the other breeds. Suffolks had the lowest lean to bone ratio.


Sign in / Sign up

Export Citation Format

Share Document