Primal Joints Research Articles

Assessing beef carcass tissue weights using computed tomography spirals of primal cuts

More than 800 beef primal cuts from 44 Aberdeen Angus and Limousin-cross steers carcasses were scanned using spiral computed tomography (CT) and dissected. Thresholds for the segmentation of fat, muscle and bone in the CT spirals were estimated with the objective of assessing the weight of these tissues in the primal cuts and in the entire carcasses. Thresholds were estimated using half of the dataset (DBE) and then validated in the other half (DBV). Automatic image analysis procedures were used to assess tissue weights. The R 2 of the regression between primal tissue weight by dissection and CT were high in both datasets for fat (DBE, 0.89; DBV, 0.92), muscle (DBE, 0.99; DBV, 0.99) and bone (DBE, 0.95; DBV, 0.97). The estimation of total carcass tissue weights were also very accurate for the three tissues ( R 2 values of 0.95 to 0.96), indicating that CT scanning may deliver very accurate information on beef carcass composition faster and with lower cost than physical dissection and without damaging or depreciating the primal joints.

X-ray computed tomography accurately assesses beef carcass composition

X-ray computed tomography (CT) scanning of live animals and carcasses provides a very accurate assessment of the weights of fat, muscle and bone in pigs (Dobrowolski et al., 2003) and sheep (Johansen et al., 2007). Although the limiting size of the CT gantry prevents CT scanning of live beef cattle, beef primal joints are small enough to be scanned. Navajas et al. (2008) explored the use of spiral CT scanning (SCTS) to quantify beef carcass composition. The automatic image analysis developed provided very accurate assessments of primal and carcass composition (Navajas et al, 2008). The objective of this study was to evaluate the accuracy of this novel method for assessing beef primal cut and carcass composition in an independent dataset.

Effects of a quantitative trait locus for increased muscularity on carcass traits measured by subjective conformation and fat class scores and video image analysis in crossbred lambs

A quantitative trait locus (QTL) for increased loin muscularity (TM-QTL) has previously been identified in purebred Texel sheep. Crossbred lambs born out of Mule ewes mated to heterozygous Texel sires for the TM-QTL were evaluated for a range of carcass traits. Lambs were genotyped and classified as carriers (n = 62) of a single copy of the TM-QTL and non-carriers (n = 49). In this study, the effects of the TM-QTL on carcass attributes were investigated using subjective classification scores for conformation and fatness, and measurements from a video image analysis (VIA) system. In addition, refined prediction equations to estimate weights of primal joints (leg, chump, loin, breast and shoulder) were obtained by calibrating the VIA system against computer tomography (CT) measurements in the loin region. The new refined prediction models increased the accuracy of prediction of all primal cuts on an average of 16% compared to previously derived standard VIA prediction equations. The coefficient of determination (R2) of the VIA system to predict in vivo CT measurements ranged from 0.39 to 0.72 for measurements of Musculus longissimus lumborum (MLL) area, width and depth, lumbar spine length, loin muscle volume and loin muscularity index. Using VIA estimates of CT-measured loin muscle traits, a significant increase in depth (+2.7%) of the MLL was found to be associated with the TM-QTL. Conformation and fatness scores and the shape of the carcass measured as individual lengths, widths and areas by VIA were not significantly influenced by the TM-QTL. Primal meat yields estimated using both standard and refined VIA prediction equations were not significantly affected by the TM-QTL. However, carcass ‘compactness’ was found to have significantly increased in carrier lambs. The weight of the dissected MLL estimated using VIA information was greater (+2.6%) for carriers compared to non-carriers. To conclude, neither the current industry carcass evaluation system for conformation and fatness nor the standard VIA system is able to identify the effect of the TM-QTL in the loin region in the moment. However, the calibration of the VIA system against CT measurements resulted in improved VIA prediction equations for primal meat yields and also showed moderate potential to estimate loin muscle traits measured by CT and to detect, partially, the effect of the TM-QTL on these traits.

Evaluation of Video Image Analysis (VIA) technology to predict meat yield of sheep carcasses on-line under UK abattoir conditions

The Meat and Livestock Commission’s (MLC) EUROP classification based scheme and Video Image Analysis (VIA) system were compared in their ability to predict weights of primal carcass joints. A total of 443 commercial lamb carcasses under 12 months of age and mixed gender were selected by their cold carcass weight (CCW), conformation and fat scores. Lamb carcasses were classified for conformation and fatness, scanned by the VIA system and dissected into primal joints of leg, chump, loin, breast and shoulder. After adjustment for CCW, the estimation of primal joints using MLC EUROP scores showed high coefficients of determination ( R 2) in the range of 0.82–0.99. The use of VIA always resulted in equal or higher R 2. The precision measured as root mean square error (RMSE) was 27% (leg), 13% (chump), 1% (loin), 11% (breast), 5% (shoulders) and 13% (total primals) higher using VIA than MLC carcass information. Adjustment for slaughter day and gender effects indicated that estimations of primal joints using MLC EUROP scores were more sensitive to these factors than using VIA. This was consistent with an increase in stability of the prediction model of 28%, 11%, 2%, 12%, 6% and 14% for leg, chump, loin, breast and shoulder and total primals, respectively, using VIA compared to MLC EUROP scores. Consequently, VIA was capable of improving the prediction of primal meat yields compared to the current MLC EUROP carcass classification scheme used in the UK abattoirs.

Genetic parameters for carcass composition and performance data in crossbred lambs measured by Video Image Analysis

A total of 7074 crossbred lambs, produced by mating crossbred Mule ewes with terminal sire rams were used in this study. Of these, 630 were scanned using a Video Image Analysis (VIA) to estimate carcass quality traits. Genetic parameters for average daily gain (ADG), scanning live weight (SW), ultrasonic measures of muscle (UMD) and fat (UFD) depths, cold carcass weight (CCW) and VIA measurements of primal carcass joint weights (LEG, CHUMP, LOIN, BREAST and SHOULDER) were estimated using multivariate animal models. Additionally, VIA traits were evaluated under a repeatability model, considering the primal joints as repeated measures of the same trait. Direct heritability estimates were low to moderate (0.08–0.26) for VIA measurements of primal joints. Repeatability estimates for VIA traits were high (>0.90). Moderate to high heritability estimates (0.25–0.55) were found for performance traits (ADG, SW, UMD and UFD) and CCW. Genetic correlations between VIA traits and ADG were strong (0.75–0.93). Most of the VIA traits were highly correlated to SW (0.60–0.97). UFD was significantly negatively correlated with UMD (−0.22), ADG (−0.18) and CCW (−0.18). The results of this study suggest that selection on performance and carcass traits, measured by VIA, could possibly improve primal meat yield of carcass cuts without increasing the overall carcass fatness. High repeatability estimates of VIA traits and moderate heritabilities of the most valuable carcass joints suggests that including VIA information in breeding programs would be useful in order to improve carcass quality.

The effect of slaughter weight on carcass characteristics of Holstein-Friesian male cattle

The commercial value of beef carcasses can be assessed by several methods including the yield of primal joints and meat quality characteristics. However, it is also important to determine the composition of the carcass in terms of lean, fat and bone concentrations, and to evaluate individual fat components of the carcass, to provide an overall assessment of the commercial value of the carcass. The objective of the present study was to evaluate the effect of slaughter weight on carcass composition of Holstein-Friesian bulls and steers offered cereal-based rations.

Primal joints and hind-leg cuts of entire and castrated Javan rusa ( Cervus timorensis russa) stags

The effects of castration on the primal joints and the cuts of the leg joint of Javan rusa ( Cervus timorensis russa) stag carcases was investigated at three slaughter ages (13, 19 and 25 months). Castration reduced the weights of some primal joints in the 19- and 25-months age groups, but not at 13 months. At 19 months, the neck, and neck plus chuck, were heavier by 35 and 17% respectively in entires ( P<0.05), and at 25 months entires had heavier carcases, shoulder, forequarter and hindquarter ( P<0.05). The leg and saddle joints were approximately 39 and 18% of the side, respectively, for both treatments and all ages. The proportions of the neck, and neck plus chuck, were higher ( P<0.05) in 19-month old entires than castrates. There were few significant differences between treatments in the weight or proportion of the hind leg cuts at any slaughter age, but in the 25-months group the silverside was 8% ( P<0.05) heavier in entires. In both castrates and entires, there appeared to be an increase in the percentage of the rump as the animals grew from 13 to 19 months of age.

Effect of time of deboning and sample size on drip loss of pork

The effects of time of deboning and sample size on drip loss of pork samples (m. longissimus) was studied in relation to the weight loss of the carcass sides or joints using two groups of 16 carcasses. One side of each carcass was cut and sampled at 1 day post mortem and served as a control. The other carcass sides were sampled for meat quality measurements after storage for another 5 days, either without cutting (group 1, n=16) or after cutting into primal joints (group 2, n=16). It was found that weight loss of carcass sides and joints increased with time, but at a decreasing rate. Drip loss largely decreased when meat samples were taken at a later time post mortem. The 48 h drip loss of the meat samples taken at 6 days post mortem was approximately 6% lower than in samples taken at 1 day post mortem. This reduction in drip loss was of the same magnitude as the weight loss of the carcass sides or the joints during 5 days storage. It is suggested that ‘leaking out’ explains most of the reduction in drip loss when sampling at a later time post mortem, and is not due to an improvement of water-holding capacity of the meat. It was also found that standardising the sample size increased drip loss. The effect of sample size is discussed in relation to the carcass lean content. Storage had little or no effect on other meat quality traits. ©

The bacteriological quality of British beef 3. Frozen primal joints

The bacteriological status of 286 primal cuts stored frozen in intervention stores in England, Scotland and Northern Ireland for between 18 and 216 weeks was assessed in two surveys carried out during 1993 (120 cuts) and 1994 (166 cuts). Overall the aerobic plate count at 25°C and the presumptive pseudomonad counts were <10 5 cm 2 on 269 (94%) and 273 (95·5%) of the cuts, respectively. Similarly the coliform and enterococcal counts were <10 3 cm 2 on 98·3% and 97·9% of the cuts, respectively. These findings suggest that the quality of dressing and butchery of the carcasses was of a generally satisfactory standard although on occasions there may have been suboptimum hygiene control during slaughter and butchery or some delay before freezing. The bacterial numbers were higher on average on the cuts obtained from the lower part of the carcass while there was a tendency for the number of aerobic spoilage organism to decrease slightly with increasing storage time. Evidence was obtained in the second survey which indicated differences between microbiological quality of meat coming from different boning plants although it was not possible to make a detailed evaluation of this point as the number of cuts available for sampling from each plant differed in each year.

Path generation for robotic cutting of carcasses

Abstract Definition of cut paths for the production of primal joints from meat carcasses is an important requirement for automated meat processing. This paper presents methods for path prediction for cuts selected from the evisceration and butchery procedures in the production of pork meat. The cuts are separated into three categories: (1) those that pass through anatomical features of a carcass; (2) cuts that can be related to anatomical features but do not pass through these features; and (3) cuts that can only be extrapolated from a specific model fitted to individual carcasses according to the principal dimensions. Consideration is given to the relationship that exist between each cut and anatomical carcass features or dimensions. The procedures implemented take advantage of the approach taken by butchers who perform the cuts described. Trials have been conducted using an automated butchery system which generates cutter trajectories from the models developed in this paper. The system produces primal cuts considered acceptable and similar to those produced by butchers. Work continues to examine the industrial issues, particularly cutting speed and yield control.

The response of highly productive rabbits to dietary lysine content

The lysine requirement of rabbits based on total lysine or on faecal digestibility was investigated. Five diets containing from 0.64 to 0.82% of crude lysine were made by supplementing a basal diet with L-lysine HCl. Apparent lysine digestibility (%) was 74.2±1.0 ( n=9) in the basal diet and 104.4±7.4 for L-lysine HCl, as estimated by the difference method. A feeding trial using 440 rabbit does was carried out over a 5-months experimental period. Milk production was measured in 70 lactations. Reproductive performance traits (parturition interval, prolificacy, kit mortality) did not improve for dietary lysine levels above 0.68 or 0.52% of crude and digestible lysine, respectively. Total milk production was affected quadratically (P < 0.001) by dietary lysine content showing a maximum for 0.80 or 0.64% of crude and digestible lysine, respectively. As a consequence, a positive but decreasing response of growth of kits and feed conversion rate to dietary lysine level was observed. A growth trial was also conducted over the fattening period using 965 weaned rabbits. Carcass traits were determined in 125 rabbits. Average daily gain and carcass dressing percentage increased (P < 0.001) with increasing dietary lysine content, but no response was found beyond 0.76 or 0.60% of crude or digestible lysine, respectively. Feed conversion rate, mortality, and proportion of primal joints in the carcass were not significantly affected (P > 0.05) by type of diet.

Carcase composition and the use of sample joints in the indigenous Malawi goat

Few data are available on the growth and carcase characteristics of the indigenous Malawi goat, despite the fact that goats provide 20% of the meat consumed in Malawi. Better husbandry and breeding programmes can only be developed and implemented when adequate data on the performance and potential of populations have been collected. This trial was undertaken to provide base line data, in order to allow comparisons to be drawn when alternative management strategies are adopted.Does were housed in a blue-gum-pole khola, roofed with galvanised iron, in pens measuring 4m2. Each pen held 10-14 does. Feeding was based upon the grazing of indigenous pastures but the goats also had access to maize stover during the dry season. Kids were weighed at birth and fortnightly thereafter. Castrate kids, in groups of S, were slaughtered at birth and at intervals of 5kg between Skg and 25kg. Following slaughter, carcases were split down the backbone, weighed, packed into individual polythene bass and stored at -20°C to await dissection. In March 1990 right hand sides were thawed, weighed and cut into six primal joints. To reduce any errors caused by abattoir procedures the axis vertebra was removed from all carcases and discarded. Each joint was then subjected to a full dissection, using butchers’ knives, into lean, bone and fat components and the weight of each component recorded. The data generated from these dissections were used to develop aliometric growth curves for each joint and for each tissue, using multiple regression analysis.

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

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.

Carcass composition in male fallow deer: age and castration effects on dissected tissue distribution

ABSTRACTTwenty-eight male fallow deer (Dama dama), 14 entire and 14 castrated (seven each 1- and 2-year-old) were slaughtered and their carcasses jointed. Each joint was separated into venison, trim A (low visible fat, diced pieces), trim B (pieces suitable only for mincing), waste and bone. Castration had a significant and cumulative effect on live and carcass weights. At 1 year of age castrated males were 80 g/kg lighter in live weight; at 2 years this difference had increased to 119 g/kg. The pattern for differences in hot and cold carcass weights was similar, being 66 and 148 g/kg lighter at 1 and 2 years old, respectively.Castration caused small but significant shifts in the proportions of the primal joints, and the proportions of venison, trim A and trim B. Castrated males had smaller neck (9 g/kg) and saddle (10 g/kg) joints, but 18 g/kg larger legs. In the whole carcass they contained 12 g/kg more venison, but correspondingly less trim A and trim B.Older animals had higher proportions of venison and lower proportions of bone. Venison distribution altered with age, but this was mainly a reflexion of changes in joint proportions.The overall effect of castration was to reduce carcass weights (on which producers are paid) and reduce venison production proportionately to 0-97 and 0-88 of that achieved in 1- and 2-year-old entire males respectively. In some market situations castration may be an acceptable method of producing venison outside of the normal peak production, but the reduced production would require higher schedule prices to be economically viable for the producer.

Lean meat quality of different pig breed types

Major attributes of pig lean meat quality are colour and the amount of exudate lost during storage. These can be influenced by genotype and preslaughter handling. Surprisingly, there is hardly any Information on the inherent meat quality potential of different breeds of pig in the UK and this is particularly true of the traditional breeds. While these may form a negligible part of the British pig population, with the increasing concern at the apparent recent increase in the incidence of PSE meat, use of genes from possibly-resistant traditional breeds in commercial hybrids might be valuable to improve quality. In this work therefore, eleven breeds of pig were compared, each represented by about twenty animals from at least two different source herds (see Table 1). Both gilts and castrates were represented. They were fed a diet containing 20% protein ad libitum and slaughtered at a live weight averaging 62 kg after having been subjected to the minimum of stress. The pH in the H. longissimus dorsi (LD) was measured at 45 min post mortem. After overnight chilling the carcasses were cut into primal joints and the loin joint scored for shape of the LD, coarseness of the grain of the muscle fibres and ‘setting’ of the joint. Setting is an important quality characteristic in that it facilitates butchery and enhances the appearance of retail cuts. Measurements of reflectance and loss of exudate during storage were made on the LD. Reflectance was measured using an EEL meter and exudation was determined after storage at 1°C for 3 days.

The effect of feeding period and trenbolone acetate on the potential of culled dairy cows for beef production

ABSTRACTSixty-four Friesian/Holstein cows culled from dairy herds were selected for uniformity and general health. They were allocated to five groups of 12 on the basis of body condition and live weight excluding the two cows at each extreme. These four cows indicated the range of condition and live weight in the sample and were slaughtered at the beginning of the trial with one group of 12 cows. Of the remaining four groups, two were implanted with 300 mg trenbolone acetate (Finaplix, Hoechst) and two used as unimplanted controls; one implanted group and one control group were slaughtered after 60 days and the remaining cows after 100 days. All cows were individually fed to appetite on a pelleted diet of 500 g dried lucerne and 500 g barley per kg. After slaughter the left side of each carcass was cut into primal joints and then separated into fat, lean and bone.Implantation resulted in greater live-weight gains to 60 days (1·35 v. 112 kg/day, P &gt; 0·05) and to 100 days (1·31 v. 0·92 kg/day, P &lt; 0·01), greater lean meat production and an increase in the lean proportion of carcasses.Feeding cows for 100 days rather than for 60 days led to higher slaughter weights but daily live-weight gain decreased and food intake increased progressively between 60 and 100 days. Carcasses from cows slaughtered at 100 days had significantly higher lean, fat and bone weights (P &lt; 0·01) but as a proportion of side weight only the fat proportion of the carcass was significantly increased (P &lt; 0·05).It was concluded that the supplementary feeding of cull cows produced heavier carcasses but at these high rates of gain increased yield was at the expense of proportionately more fat in the carca?.s. This problem was partially countered by implantation with trenbelone acetate.

Variation among beef breeds in carcass retail value at constant carcass saleable meat content and percentage of higher priced cuts

Data from the single slaughter point trials of the Meat and Livestock Commission's (MLC) beef breed evaluation programme were used to examine the importance of retail value (RV) calculation in breed evaluation trials. The analysis involved a total of 2010 carcasses comprising four production system groups. Sire breeds included Aberdeen-Angus, British Friesian, Charolais, Devon, Hereford, Galloway, Limousin, Lincoln Red, Luing, Simmental, South Devon, Sussex and Welsh Black. RV was computed as the sum of the values of trimmed deboned primal joints expressed as pence per kilogram of carcass weight. 1981 prices from MLC's Retail Prices Survey for England and Wales were used. A model was fitted to the RV data for each of the production system groups with effects for sire breed, year and sire breed × year interaction, and with regression on saleable meat percentage in carcass (SM). The largest difference recorded between sire breeds was 2·1 pence/kg (0·85% of overall mean RV). The pooled within-system residual standard deviation after fitting the model was 1·4 pence/kg. When regression on the percentage of total saleable meat in the higher priced cuts (SMD) was added to the model, the corresponding range and residual standard deviation were reduced to 1·0 and 0·8 pence/kg, respectively. In the circumstances, the calculation of RV would, therefore, make only a minor refinement to the results.

A comparison of different predictors of the lean content of pig carcasses 1. Predictors for use in commercial classification and grading

ABSTRACTCarcass measurement and dissection data for 1176 pigs were used to examine the suitability of different measurements for predicting carcass lean percentage in commercial classification and grading. Three carcass weight groups with means of 47, 72 and 93 kg, were analysed separately. Similar results were obtained and those for the 72 kg group are given in this abstract. The s.d. of percentage carcass lean in this group was 3·84. Visual conformation score, carcass length and m. longissimus depth were valueless as predictors (residual s.d. of carcass lean percentages were 3·84, 3·77 and 3·80 respectively). Fat thickness measurements taken on the exposed surface of the split carcass provided a less precise prediction (best residual s.d.=2·89) than fat measurements taken over the m. longissimus using the optical probe (best residual s.d. = 2·20). The probe measurements were taken 6·5 cm from the dorsal mid line at fixed positions along the carcass from 4/5th cervical vertebrae to the 5/6th lumbar vertebrae. Precision of prediction showed a regular pattern with highest levels at the last rib (the P2 position currently used in the Meat and Livestock Commission classification scheme) and at the 13th rib, with lower values anteriorly and posteriorly. These two measurements in multiple regression were more precise than any other pair of measurements for predicting both percentage carcass lean (residual s.d. = 2·16) and the lean percentage in individual primal joints.

Changes in the microbiology of vacuum-packaged beef.

The development of the microbial flora on meat stored in vacuum‐bags at 0–2° for up to 9 weeks was studied. Although the proportion of lactic acid bacteria increased relative to the aerobic spoilage organisms, the numbers of the latter continued to increase throughout storage. The initial contamination of the meat before vacuum‐packaging was important; meat with a very low initial number had lower numbers of bacteria throughout storage for up to 9 weeks and steaks cut from such meat which had been stored always had 1–2 days’ additional aerobic shelf life at 4°. Spoilage of these steaks was due either to slime formation and off‐odour associated with high counts of presumptive Pseudomonas spp., or by discoloration and souring (lactic acid bacteria). Extract release volume and pH measurements performed on the vacuum‐packaged primal joints were only of value in determining the onset of aerobic spoilage when large numbers of Gram negative organisms were present, whereas the titrimetric method of spoilage evaluation of the vacuum‐packaged meat showed a correlation with spoilage due to lactic organisms.