Carcass Fat Score Research Articles

Evaluation of maize silage in the diet of finishing steers

Interest in the production of maize silage in Ireland has increased in the last few years. The objective of this experiment was to evaluate the performance of steers when fed maize or grass silage based diets ad libitum and supplemented with varying levels of concentrates.Sixty continental cross steers were blocked on the basis of live weight (av. initial weight = 617 kg) and breed (Charolais, Limousin and Simmental) and were allocated to one of the following six dietary treatments with 10 animals per treatment: A) maize silage-1 (sown under polythene) plus 2 kg concentrates (22% CP); B) 50:50 mixture of maize silage-2 (grown without the use of polythene):grass silage plus 4 kg concentrates (16% CP); C) maize silage-2 plus 4 kg concentrates (16% CP); D) maize silage-3 (as for silage-2 but with additive applied to control aerobic deterioration) plus 4 kg concentrates (16% CP); E) grass silage plus 4 kg concentrates (16% CP); F) grass silage plus 6 kg concentrates (14% CP). The steers were fed for 105 days during which live weight gains and group intakes were measured. After slaughter carcass gains were calculated (using an initial kill-out of 53%), kidney knob and channel fat weights were measured and carcass conformation and fat scores were taken.

Evaluation of maize silage in the diet of finishing steers

Interest in the production of maize silage in Ireland has increased in the last few years. The objective of this experiment was to evaluate the performance of steers when fed maize or grass silage based diets ad libitum and supplemented with varying levels of concentrates.Sixty continental cross steers were blocked on the basis of live weight (av. initial weight = 617 kg) and breed (Charolais, Limousin and Simmental) and were allocated to one of the following six dietary treatments with 10 animals per treatment: A) maize silage-1 (sown under polythene) plus 2 kg concentrates (22% CP); B) 50:50 mixture of maize silage-2 (grown without the use of polythene):grass silage plus 4 kg concentrates (16% CP); C) maize silage-2 plus 4 kg concentrates (16% CP); D) maize silage-3 (as for silage-2 but with additive applied to control aerobic deterioration) plus 4 kg concentrates (16% CP); E) grass silage plus 4 kg concentrates (16% CP); F) grass silage plus 6 kg concentrates (14% CP). The steers were fed for 105 days during which live weight gains and group intakes were measured. After slaughter carcass gains were calculated (using an initial kill-out of 53%), kidney knob and channel fat weights were measured and carcass conformation and fat scores were taken.

Productivity and carcass composition of Friesian, Meuse-Rhine-Issel (MRI) × Friesian and Belgian Blue × Friesian steers

AbstractOne hundred and twenty spring-born steers, comprising 40 Friesians (FR), 40 Meuse-Rhine-lssel (MRI) × Friesians (MR), and 40 Belgian Blue × Friesians (BB) were reared together from 3 weeks of age to the start of their second winter. During the second winter there was a 3 (FR, MR and BB breed types) × 2 (3 kg and 6 kg supplementary concentrates per head daily with grass silage ad libitum) × 2 (96- and 220-day finishing periods) factorial arrangement of treatments (10 animals per subgroup). Carcass weights and grades were recorded after slaughter at the end of the second winter, and one side from each of 96 carcasses (eight per subgroup) was dissected into bone, muscle, intermuscular fat and subcutaneous fat. A sample of m. longissimus from the 10th rib was chemically analysed. Slaughter weights and carcass weights per day from arrival to slaughter were 796, 813 and 828 (s.e.d. 11·7) g and 419, 440 and 457 (s.e.d. 7·1) g for FR, MR and BB, respectively. Corresponding carcass weights were 314, 329 and 342 (s.e.d. 4·5) kg. BB had better conformation than both FR and MR. BB also had a lower carcass fat score, lower proportions of bone, intermuscular fat and subcutaneous fat, a higher proportion of muscle and muscle with higher proportion of moisture and a lower proportion of lipid than FR and MR. The higher level of concentrates increased side iveight by 8 kg, but the overall effects on carcass composition were small. The longer finishing period increased side weight by 25 kg and was associated with significantly reduced proportions of bone and muscle and an increased proportion of fat. Allometric regression coefficients for carcass weight on slaughter weight, and for bone, muscle and fat weights on side weight were 1·19, 0·39, 0·80 and 2·16, respectively. It is concluded that despite the better carcass conformation of MR, there was little difference in carcass and muscle composition between FR and MR. BB, in addition to having a higher growth rate and better carcass conformation than FR, also had more muscle in the carcass, more of the total muscle in the higher value joints and a lower proportion of lipid in the muscle. It was calculated that FR, MR and BB would have similar proportions of separable fat in the carcass at approximate carcass weights of 300, 320 and 400 kg, respectively.

Effect of frame size, muscle score, and external fatness on live and carcass value of beef cattle.

Commercial slaughter steers (n = 329) and heifers (n = 335) were selected to vary in slaughter frame size and muscle thickness score, as well as adjusted 12th rib fat thickness. After USDA carcass grade data collection, one side of each carcass was fabricated into boneless primals/subprimals and minor tissue components. Cuts were trimmed to 2.54, 1.27, and .64 cm of external fat, except for the bottom sirloin butt, tritip, and tenderloin, which were trimmed of all fat. Four-variable regression equations were used to predict the percentage (chilled carcass weight basis) yield of boneless subprimals at different fat trim levels (.64, 1.27, and 2.54 cm) as influenced by sex class, frame size, muscle score, and adjusted 12th rib fat thickness. Carcass component values, total carcass value, carcass value per 45.36 kg of carcass weight, and live value per 45.36 kg of live weight were calculated for each phenotypic group and external fat trim level. Carcass fatness and muscle score had the most influence on live and carcass value (per 45.36 kg weight basis). Carcasses with .75 and 1.50 cm of fat at the 12th rib were more valuable as the trim level changed from 2.54 cm to .64 cm; however, for carcasses with 2.25 cm of fat at the 12th rib, value was highest at the 2.54 cm trim level. Value was maximized when leaner cattle were closely trimmed. There was no economic incentive for trimming light-muscled or excessively fat carcasses to .64 cm of external fat.

Growth and carcass composition of Friesian, Limousin × Friesian and Blonde d'Aquitaine × Friesian steers

ABSTRACTOne hundred and twenty spring-born steers comprising 40 Friesians (FR), 40 Limousin × Friesians (LM), and 40 Blonde d'Aquitaine ' Friesians (BL), were reared together from shortly after birth to slaughter at a mean age of 771 days. They were at pasture in summer and were housed and offered grass silage plus concentrates in winter. All were implanted with anabolic agents. During the finishing winter, there was a 3 (breed types) ' 2 (3 or 6 kg concentrates per day) ' 2 (94 or 181 day finishing period) factorial arrangement of treatments.Slaughter weights per day of age, carcass weights per day of age and carcass weights of FR, LM and BL were 846, 828 and 866 (s.e. 8·0) g, 464, 476 and 497 (s.e. 4·9) g and 358, 368 and 385 (s.e. 3·8) kg respectively. LM had lower carcass length, carcass depth, leg length and leg width values than FR or BL but when these measurements were expressed per kg carcass weight the values for LM and BL were similar. Both LM and BL had better carcass conformation than FR, and BL had a lower carcass fat score than either FR or LM between which there was no difference. FR, LM and BL had carcass lean, fat and higher-priced lean proportions of 634, 669 and 685 (s.e. 3·7), 185, 168 and 144 (s.e. 3·7) and 352, 361 and 361 (s.e. 1·4) g/kg respectively.Increasing the concentrate level from 3 to 6 kg per day increased side weight by 9·6 kg (P < 0·001). This consisted of 0·6 kg bone, 3·3 kg lean and 5·7 kg fat. Extending the finishing period from 94 to 181 days increased side weight by 30·3 kg (P < 0·001). This consisted of 2·6 kg bone, 12·0 kg lean and 15·7 kg fat. Allometric regression coefficients for side lean, bone and fat weights on side weight were not significantly affected by breed type or concentrate level. The coefficients for lean, bone and fat were 0·80 (s.e. 0·04), 0·58 (s.e. 0·05) and 2·27 (s.e. 0·16) respectively. The coefficients for weights of lean in the hind-shin, fore-shin, fillet and brisket on side lean weight were 0·8 or lower. The corresponding coefficients for silverside, inside round, knuckle, rump and strip-loin were between 0·8 and 1·0 while the flank, shoulder, neck, chuck, plate, fore-rib and cube-roll had coefficients in the range 1·0 to 1·5.

Growth traits and composition of two- and three-way-cross intact male progeny of Bos taurus and Bos indicus X Bos taurus dams.

Feedlot traits, carcass traits and distribution of commercial cuts of crossbred intact male progeny (n = 556) from young and mature Hereford, Red Poll, Hereford X Red Poll, Red Poll X Hereford, Angus X Hereford, Angus X Charolais, Brahman X Hereford and Brahman X Angus dams were evaluated. First-calf heifers were bred to Red Angus bulls; Santa Gertrudis sires were used for each cow's second and third breeding seasons. Calves from these young dams were slaughtered at 13 mo. Calves of mature dams were all sired by Limousin bulls and slaughtered at 12 mo. Dam breed was a major source of variation in most bull traits. Progeny of Brahman-cross dams were inferior (P less than .01) in daily gain, final weight, carcass weight and in edible cuts/day of age compared with progeny from Bos taurus dams. Intact male progeny of Angus X Charolais dams ranked highest in longissimus area, cutability, and edible cuts/day of age. The range of dam breed means in percentage of steak, roast, bone-in cuts (chuck short ribs and back ribs), short plate and thin cuts, and lean trim was just over 1%. Greater variation among dam breeds existed in fat measurements. Analyses in which Hereford-Red Poll diallel data for young dams and mature dams were combined showed positive maternal heterosis for dressing percentage (P less than .05), carcass weight (P less than .05), carcass weight/day of age (P less than .05), estimated carcass fat (P less than .05), fat thickness (P less than .01) and marbling score (P less than .01). Reciprocal effects were inconsequential. Results illustrate the importance of dam breed-type effects in formulating breeding strategies for commercial beef herds.

Effects of pelleting, added sodium bentonite and fat in a wheat-based diet on performance and carcass characteristics of small white turkeys

Turkeys of a small white strain were fed on diets of constant energy to protein ratio, based on wheat-soya bean meal, with 0, 30, 60 or 90 g added fat kg −1, in mash form or as pellets, with or without the addition of 25 g sodium bentonite kg −1 as a pellet hardener. Pelleted diets resulted in greater liveweights than mash at 84 days of age when the diet included no added fat (4.93 vs. 4.52 kg, mixed sexes) or 30 g fat kg −1 (5.14 vs. 4.91 kg), but not with 60 (5.17 vs. 5.16 kg) or 90 g fat kg −1 (5.27 vs. 5.22 kg). Pelleting did not affect feed efficiency to 84 days, but increased carcass fat scores and grades. Sodium bentonite did not affect liveweight, feed intake or feed efficiency, or pellet durability when the diet contained either 0 or 90 g added fat kg −1, but increased durability of pellets with 30 or 60 g added fat kg −1. Feed efficiency increased by 1.0% for each 10 g kg −1 increase in fat incorporated in the diet. Carcass fat scores and grades and carcass skin yields increased with dietary fat level. Effects of pelleting and added dietary fat on carcass characteristics as well as weight gain and feed efficiency should be considered when establishing practical feeding programmes for turkeys.

Effect of Grower and Finisher Protein on Performance, Carcass Grade, and Meat Yield of Turkey Broilers

Three grower diets, varying in protein content from 220 to 255 g/kg, and three finisher diets, ranging from 162 to 197 g protein/kg, were fed to turkeys of a Small White strain in a factorial experiment involving 794 poults.Weight gains from 28 to 70 days increased linearly with increasing grower protein level, and the differences were maintained until final weighing at 91 days. Weight gains and feed efficiencies from 70 to 91 days increased with increased finisher protein, although weight gains of females increased less rapidly than those of males when protein exceeded 182 g/kg.Carcass fat and fleshing scores increased with higher finisher protein. Meat yield tended to increase and bone yield decreased, relative to eviscerated carcass weight, with higher finisher protein.Higher carcass fat scores for females over males were associated with increased total skin and abdominal fat yields. Females scored higher for fleshing but did not differ from males in meat yield and yielded less total bone.Protein requirement for optimal weight gain of turkey broilers of the Hybrid 1000 strain from 28 to 70 days of age was at least 255 g/kg with diets of 3.20 Meal (13.9 MJ) true metabolizable energy (TME)/kg. Males required 197 g and females at least 182 g protein/kg with 3.33 Meal (13.9 MJ) TME/kg from 70 to 91 days. Feeding programs incorporating less dietary protein may adversely affect carcass quality, growth, and feed efficiency.

Effect of Starter and Finisher Protein on Performance, Carcass Grade, and Meat Yield of Broilers

Three starter diets ranging from 205 to 242 g protein/kg with 3.30 Meal (13.8 MJ) true metabolizable energy (TME)/kg and four finisher diets ranging from 166 to 227 g protein/kg with 3.36 Meal (14.1 MJ) TME/kg were fed to broilers in a factorial experiment involving 1650 chickens.Weight gains to 4 weeks improved with increasing starter protein and the differences were maintained to 8 weeks. Feed efficiency to 4 but not 8 weeks improved with increasing starter protein. Carcass fleshing grades and breast meat yield at slaughter (6, 7, and 8 weeks) increased with higher starter protein.Weight gains from 4 to 8 weeks were not significantly affected by finisher protein levels, but feed efficiency of males was improved when the diet contained 189 g or more protein/kg. Finisher protein had little effect on carcass fat scores, but carcass skin and abdominal fat yields decreased with increasing protein. Total meat and breast meat yields increased together with the finisher protein.Increased total mortality and losses attributed to leg problems were associated with the highest starter protein level. However, total mortality decreased linearly with increasing finisher protein. Incidence of sudden death syndrome was not significantly related to diet.

The Effect of the Level and Source of Dietary Fat on the Growth, Feed Efficiency, Grade and Carcass Composition of Turkeys

INTRODUCTIONTHE incorporation of fat from many animal and vegetable sources in balanced diets has often been shown to reduce the feed intake and increase the growth rate and efficiency of feed utilization of turkeys and chickens (Salmon, 1969; Vermeersch and Vanschoubroek, 1968). The inclusion of fat in the diet has been shown to improve the carcass fat scores of turkeys (Touchburn and Naber, 1966; Blakely et al., 1965).The nature of the fat included in the diet has long been known to influence the properties of the carcass fat of many species (Cruickshank, 1934; Beadle et al., 1948; Klose et al., 1952). The carcass fat of turkeys fed 9% soybean (SBO) or rapeseed oil (RSO) to 6 weeks of age was found to be very similar in fatty acid composition to the dietary fat (Salmon, 1969).Fats from many different sources have been used in studies reported over the…

Meat production characteristics of Turkish native breeds: I. Fattening, slaughter and carcass traits of lambs

The present study was conducted to determine the slaughter and carcass traits of male lambs of the Akkaraman (A), Morkaraman (M), Awassi (IW), Karayaka (KR), Kıvırcık (KV) and Middle Anatolian Merino (MAM) sheep breeds. Fattening of all lambs started when they were at 90 days at weaning and finished when they reached bodyweight of 40 kg. The cold dressing percentage of lambs of A, M, and IW breeds were significantly lower than those of KV, KR and MAM. Fat depth and muscle area were significantly greater in KV and MAM lambs than those of the other breeds. There were significant differences among breeds in shoulder, leg and lean weights. Weights of back loin in KV and MAM lambs were significantly greater than those of the other breeds. The highest values for carcass fleshiness were obtained in MAM and IW lambs, but they had a significantly lower carcass fatness score. There were significant differences among the breeds in carcass compactness and leg conformation. The results of the present study indicated that A and MAM breeds could be recommended for desirable carcass characteristics.Keywords: Carcass cuts, indigenous sheep breed, intensive lamb finishing, meat formation, SEUROP classification