The effects of plane of nutrition and slaughter weight on the performance and carcass composition of continental beef bulls given high forage diets

1994 ◽  
Vol 58 (1) ◽  
pp. 41-47 ◽  
Author(s):  
D. C. Patterson ◽  
C. A. Moore ◽  
R. W. J. Steen

AbstractBulls (½ Blonde d'Aquitaine ⅜ Charolais) were used in a 2 × 3 factorial design experiment with two planes of nutrition in the finishing period and three slaughter weights. High and low planes of nutrition were based on diets with similar forage to concentrate ratio (0·40 of dry matter (DM)) offered ad libitum or at 0·78 of ad libitum DM intake at equal live weight respectively. The target slaughter live weights were 550, 625 and 700 kg. Twelve bulls were taken to each slaughter point and an additional five animals were killed as a pre-experimental slaughter group. Mean initial live weight was 412 (s.e. 5·3) kg at a mean age of 342 (s.e. 2·5) days. No significant interactions were found between the main factors. For the high and low planes, live-weight and estimated carcass gains were 1251 and 989 (s.e. 47·7), and 816 and 668 (s.e. 35·3) g/day respectively, the reduction in gains being similar to the proportional degree of nutritional restriction. Plane of nutrition had no effect on live-weight or carcass gain per unit of energy intake. The low plane of nutrition produced significant decreases in body cavity fat depots, subcutaneous fat in the sample joint and increased the proportions of both saleable beef and high-priced joints in the carcass.With increase in slaughter weight, energy intake per unit of live weight0·75 and rates of both live-weight and carcass gain tended to decline. The dressing proportions were 583,579 and 609 (s.e. 9·1) g/kg for the slaughter live weights of 550, 625 and 700 kg. Carcass conformation improved while fat depots in the body cavity and estimated concentration of separable fat in the carcass increased with increase in slaughter weight, and both estimated lean and bone concentrations decreased. Forequarter as a proportion of total side tended to increase with increase in slaughter weight. Slaughter weight had no effect on concentration of saleable meat or ultimate pH of carcass muscle. It is concluded that bulls of this genotype can be taken to high slaughter weights on diets having a relatively high proportion of forage as grass silage, with high rates of growth and acceptable carcass leanness.

2006 ◽  
Vol 82 (3) ◽  
pp. 397-404 ◽  
Author(s):  
R. M. Kirkland ◽  
T. W. J. Keady ◽  
D. C. Patterson ◽  
D. J. Kilpatrick ◽  
R. W. J. Steen

AbstractA total of 180 Holstein-Friesian male calves, mean age and live weight (LW) at start of the study 112 (s.d. 26·0) days and 134 (s.d. 37·6) kg, respectively, were used to evaluate the effect of slaughter weight on food efficiency and animal performance. Animals were offered concentrates ad libitum and a restricted quantity of straw and slaughtered at one of six LWs as bulls: 300, 350, 400, 450, 500 or 550 kg. A further group of cattle were slaughtered as steers at 450 kg LW. Mean age at slaughter was 247 and 434 days for bulls slaughtered at 300 and 550 kg LW respectively. Neither rate of LW or carcass gain was influenced by weight at slaughter ( P>0·05), with mean values of 1·31 and 0·70 kg/day, respectively. Food conversion ratio, killing-out proportion, carcass conformation, fat classification and weight of internal fat depots increased ( P<0·001) as slaughter weight of the bulls increased. In the comparison of steers and bulls slaughtered at 450 kg, steers had lower ( P<0·001) rates of LW and carcass gains and had a higher ( P<0·001) food conversion ratio than comparable bulls. Steers had lower ( P<0·001) estimated carcass lean, and higher ( P<0·01) estimated carcass fat concentrations than bulls slaughtered at the same LW.


1975 ◽  
Vol 20 (2) ◽  
pp. 257-265 ◽  
Author(s):  
J. F. O'Grady ◽  
F. W. H. Elsley ◽  
R. M. MacPherson ◽  
I. McDonald

SummaryThe live-weight changes of 48 sows were recorded over three reproductive cycles. All sows were given standard amounts of feed in gestation and one of four energy allowances during lactation. The daily intakes of digestible energy during lactation ranged from 12·2 to 182·2 Meal in the first, 122·9 to 192·6 Meal in the second and 132·2 to 202·2 Meal in the third lactation. Weight change in lactation responded to energy intake; sows on the lowest energy intake lost weight whilst those on the highest intake gained. At weaning of their third litters, sows on the highest energy allowance weighed 44 kg more than those on the lowest level and this was equivalent to a carcass difference of 372·3 kg at slaughter.All the sows were slaughtered after the third litters had been weaned and the carcasses were dissected into lean, subcutaneous fat+skin, and bone. Sows from all treatments had less subcutaneous fat+skin and more muscle and bone than non-pregnant gilts killed at a mean weight of 129 kg, a weight equivalent to that of the experimental animals at their first mating.The reduction in fat reserves was linearly correlated with dietary energy intake of the sows. Sows receiving the lowest energy intake in lactation possessed fat reserves which were estimated to be only 25% as great as in gilts comparable to those used to initiate the experiment. This reduction in body reserves has implications with regard to the long-term effects of feeding lactating sows low intakes of energy during 6-week lactations.


1982 ◽  
Vol 35 (2) ◽  
pp. 253-262 ◽  
Author(s):  
B. W. Butler-Hogg ◽  
J. D. Wood

ABSTRACTNinety-two British Friesians and 62 Jersey castrated male cattle were slaughtered serially in five age groups at 13, 89, 170, 339 and 507 days, and dissected fully into lean, bone, intermuscular fat, subcutaneous fat, perirenal-retroperitoneal fat (kidney knob and channel fat), omental fat and mesenteric fat. The aim was to investigate the partition of body fat in these dairy breeds and the role of the partition of fat in determining carcass value.Relative to live weight, Friesians had more lean, subcutaneous fat and carcass fat (subcutaneous and intermuscular) at most ages, and Jerseys had more kidney knob and channel fat, and intra-abdominal fat. Friesians had a higher killing-out proportion and lean:bone ratio, and thicker subcutaneous fat.The order of increasing relative growth of fat depots with total body fat as the independent variable was, for Friesians: intermuscular < mesenteric < kidney knob and channel fat < subcutaneous < omental. In Jerseys the order was: intermuscular < mesenteric < subcutaneous < kidney knob and channel fat < omental. There were only small breed differences in the distribution of subcutaneous fat between eight regions. t I is suggested that, between breeds, there is a physiological link between the capacity for milk-fat production and the partition of fat within the body, with relatively high milk-fat producers depositing proportionately more fat intra-abdominally.Since the timing of slaughter is often determined by level of external finish in beef production, the breed difference in the partition of fat, which caused Jerseys to have a higher proportion of kidney knob and channel fat, and intermuscular fat, at the same proportion of subcutaneous fat, would reduce carcass value in Jerseys compared with Friesians.


1987 ◽  
Vol 44 (1) ◽  
pp. 117-124 ◽  
Author(s):  
B. W. Butler-Hogg ◽  
I. D. Johnsson

ABSTRACTThirty-two Dorset Down × Finn Dorset female lambs were reared from 8 to 20 weeks on an ad libitum concentrate diet. They comprised four groups of eight lambs, one on each of the following treatments: (1) control, no injections; (2) daily subcutaneous injection of 0-1 mg bovine pituitary growth hormone (bGH) per kg live weight; (3) daily subcutaneous injection of 1 mg bromocriptine mesilate (Br); (4) daily injections of both bGH and Br at the same rates as treatments (2) and (3).There were no important differences in carcass composition or tissue distribution between the +bGH and +bGH+Br lambs or between the control and +Br lambs. The +bGH lambs (+bGH and +bGH+Br lambs pooled) contained significantly greater proportions of lean and bone compared with the −bGH lambs (control and +Br lambs pooled). Although carcass composition was altered by bGH treatment, the distribution of individual tissues (lean, bone and fat) was not influenced significantly.Carcass quality was improved markedly by bGH treatment: subcutaneous fat depth was reduced and the area of the m. longissimus lumborum increased. +bGH carcasses would be ranked one fat class less on the Meat and Livestock Commission fatness scale than −bGH carcasses at the same carcass weight.


1983 ◽  
Vol 36 (3) ◽  
pp. 389-397 ◽  
Author(s):  
J. D. Wood ◽  
O. P. Whelehan ◽  
M. Ellis ◽  
W. C. Smith ◽  
R. Laird

ABSTRACTThe effects of selection for low backfat thickness on tissue deposition in different body sites has been investigated in pigs. Eight castrated male and eight female pigs from each of the selection and control lines maintained at the University of Newcastle upon Tyne were used. One castrated male and one female from each line was killed at 15, 30, 45, 60, 75, 90, 105 and 120 kg live weight following ad libitum food consumption and fully dissected.There were only small effects of line on carcass composition, selected pigs having 120 g/kg more bone than controls at the mean side weight (P < 0·001) and 40 g/kg more lean (NS). At the same mean weight of subcutaneous fat, selected pigs had thinner backfat than controls (approximately 3 mm) over m. longissimus at the last rib and over the shoulder but not at the mid-rump or mid-back positions. There appears to have been a slight shift in the sites of fat deposition from above m. longissimus in the loin towards the mid-line and rump as a result of selection, even though mid-rump, C and K measurements were all included in the selection index. However, there was no difference between the lines in the weight distribution of subcutaneous fat between six regions and so these shifts must have been very localized. There was no difference between lines in the relationship between P2 fat thickness and proportion of lean in the side.The effects of selection on the sites of deposition within tissues other than subcutaneous fat were small. In particular there was no evidence that selection has caused relocation of body fat from subcutaneous to the other sites.


1991 ◽  
Vol 71 (4) ◽  
pp. 1021-1029 ◽  
Author(s):  
E. Yambayamba ◽  
M. A. Price

Fifty-three Hereford crossbred heifers (211 ± 28 (mean ± SD) kg; 197 ± 13 d of age at day 1) were used to study catch-up growth and its effects on carcass composition. Five heifers were slaughtered on day 1; the remaining 48 were randomly penned in groups of six and assigned to treatments as follows: three pens to ad libitum feeding (target gain > 1.0 kg d−1); three pens to 2 mo of feed restriction (target gain 0.5 kg d−1); followed by realimentation; and two pens to 4 mo of feed restriction (target gain: 2 mo at 0.5 kg d−1 and 2 mo at 0.0 kg d−1) followed by realimentation. Animals from one pen were slaughtered from each treatment after 2 mo, after 4 mo, and at a final slaughter weight of about 410 kg. During the final period (4 mo to slaughter), growth rate was greater (P < 0.05) in the 4-mo than in the 2-mo restricted–realimented animals or the ad-libitum-fed animals (1.91 vs. 1.18 vs. 1.02 kg d−1), respectively. Feed restriction for 2 mo had no significant effect on the composition of the three-rib cut, but 4 mo of feed restriction was associated with significantly lower and higher (P < 0.05) proportions of fat and bone, respectively, in the three-rib cut. Muscle proportion was not affected by treatment. At the final slaughter weight, no significant differences were found among treatments in the tissue proportions of the three-rib cut. It is concluded that 2 or 4 mo of feed restriction, starting at 6 mo of age, has no permanent effect on a heifer's live weight or body composition. Key words: Heifers, feed restriction, realimentation, compensatory growth, carcass composition


1985 ◽  
Vol 65 (2) ◽  
pp. 363-374 ◽  
Author(s):  
S. D. M. JONES

One hundred and eighty-nine steers comprising 63 small (S) rotational crossbreds, 66 large (L) rotational crossbreeds and 60 Holsteins (H) were fed either a concentrate diet based on corn silage and high-moisture corn, or a forage diet based on a mixture of corn silage and alfalfa haylage. All steers were fed ad libitum and slaughtered to cover a range in external fatness (0–15 mm subcutaneous fat). Steers were removed from feed 36 h and water 16 h prior to slaughter. The left side of each carcass was separated into depot fat, lean and bone. At the same proportion of subcutaneous fat (63 g/kg carcass), S and L carcasses had greater proportions of carcass lean (P < 0.001), but less fat (P < 0.01) and bone (P < 0.001) than carcasses from H Steers. Small and large carcasses had greater muscle to bone ratios (P < 0.001) than carcasses from H steers. Diet had no effect on lean tissue proportions, but forage feeding increased carcass bone (P < 0.001) and decreased carcass fat (P < 0.01). Forage feeding also resulted in carcasses with lower muscle to bone ratios (P < 0.01) than carcasses produced from grain feeding. Holstein-carcasses had more carcass fat partitioned into the body cavity depot and less into the subcutaneous depot than S and L carcasses, but diet had no effect on fat partitioning. Biological type (S, L or H) and diet were found to have a minor effect on fat distribution. The results are discussed with reference to carcass evaluation of beef and dairy cattle fed diets based on forage or grain. Key words: Biological type, diet, carcass composition, carcass grading


1976 ◽  
Vol 22 (1) ◽  
pp. 55-59 ◽  
Author(s):  
D. Levy ◽  
Z. Holzer ◽  
Y. Folman

SummaryThe effects of two levels of energy intake, ad libitum and 80% of ad libitum, of diethylstilboestrol implantation and no such treatment, and of two slaughter weights (‘450’ and ‘490’ kg), on the performance of Israeli-Friesian intact male cattle were studied.Average daily gain was 1130 g and 959 g and daily carcass gain was 630 g and 553 g for animals on ad libitum and 80% of ad libitum energy intake, respectively. Average daily gain was 1038 g and 944 g and daily carcass gain was 595 g and 562 g, for diethylstilboestrol-treated and untreated animals, respectively. Slaughter weight had little effect on rate of gain.The differences in conversion ratio of ME into live weight between treatments were small. Diethylstilboestrol-treated animals were slightly more efficient.The non-implanted animals on the restricted plane of nutrition and which had been slaughtered at ‘490’ kg had a significantly higher dressing percentage, a higher percentage of fat trim and less bone than animals slaughtered at ‘450’ kg body weight on both levels of nutrition.Among the diethylstilboestrol-implanted male calves, however, the animals fed at 80% of ad libitum feed and killed at ‘450’ or ‘490’ kg live weight had significantly more fat trim in the carcass and less bone than the animals fed ad libitum.


Author(s):  
R.W.J. Steen

Consumer demand for leaner beef necessitates a reduction in the fat content of a major proportion of the beef carcasses currently produced. It is generally accepted that reducing the plane of nutrition of beef cattle reduces fat content. However the effects on growth rate and overall efficiency of production are also important. The effects of reducing energy intake on performance and carcass composition may be influenced by the nature of the change in energy intake. An experiment has been carried out to examine the effects of reducing energy intake, either by increasing forage: concentrate ratio (F:C) in the diet or reducing dry matter intake at constant F:C.Thirty-six Friesian (F), Limousin x F and Belgian Blue x F 12-month old steers which were initially 368 kg, and which had been reared under uniform management and nutrition were used. They were purchased from dairy farms during October and November at approximately 10 days old, were aritifically reared and were at pasture from April until October. After a three week acclimatization period they were divided into blocks according to breed and live weight and allocated to the three treatments at random with each block. The three treatments were a complete diet consisting of 0.67 grass silage (719 g digestible organic matter and 144 g crude protein/kg DM; 82 g ammonia N/kg total N) and 0.33 concentrates (0.9 rolled barley and 0.1 soyabean meal) offered (1) ad libitum or (2) at 0.8 of ad libitum intake.


1981 ◽  
Vol 97 (1) ◽  
pp. 83-86
Author(s):  
C. N. Skipitaris

SUMMARYAn experiment was made with growing pigs, to investigate the effect of water restriction in combination with self-fed diets of reduced energy content upon carcass quality.The diets compared contained 5 and 30% of lucerne hay and the water treatments were ad libitum or progressively restricted amounts during the finishing period (60–90 kg live weight).Both increasing the proportion of lucerne meal and restricting water intake reduced significantly depth of backfat and the weight of total subcutaneous fat. There was no interaction between the treatments.The results are discussed in the light of the findings of Cunningham & Friend (1966).


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