Total Side Fat Research Articles

The effect of live weight gain and live weight loss on body composition of merino wethers: chemical composition of the dissected components.

Chemical composition of the dissected side parts and dissected side was measured during live weight gain (LWG) and live weight loss (LWL) to determine effects on the chemical composition of the dissected side parts. Thirty-five Merino wethers had ad libitum access to the experimental diet (17.23% CP and 12.09 MJ/kg of DE) to grow from 23.0 to 33.0 kg live weight and then were fed to lose a total of 10 kg in three periods of 25 d each at the rate of 133 g/d. Groups of five animals were slaughtered at live weights of 23.0, 26.3, 29.6, and 33.0 kg during LWG and 29.6 kg (first period), 26.3 kg (second period), and 23.0 kg (third period) during LWL. The greater dissected side weight in LWL animals than in LWG animals at 23.0 kg of live weight was due to the significantly greater chemical fat (P < .05) in the LWL animals than in the LWG animals at 23.0 kg. There were no significant differences between treatments in the protein and water weights in the dissected side. The general increase in the chemical fat in the dissected side of the LWL animals was due to the significant increase in the chemical fat in the muscle (P < .01) and bone (P < .01, 23.0 and 26.3 kg and P < .05, 29.6 kg) at each common slaughter weight and subcutaneous fat (P < .05), intermuscular fat (P < .05) kidney and channel fat (P < .05), and total side fat (P < .01) at 23.0 kg.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of live weight gain and live weight loss on body composition of Merino wethers: dissected muscle, fat, and bone.

Sheep were slaughtered after live weight gain (LWG) and live weight loss (LWL) to evaluate the effect of different periods of normal and retarded growth on dissected carcass components. Thirty-five Merino wether sheep were allowed ad libitum access to the experimental diet of 80% alfalfa chaff and 20% cereal grain (17.23% CP and 18.10 MJ/kg of GE) to grow from 23.0 to 33.0 kg live weight and then fed to lose 10 kg at 133 g/d. Five animals were slaughtered at live weights of 23.0, 26.3, 29.6, and 33.0 kg during LWG and 29.6, 26.3, and 23.0 kg during LWL. Fleece-free empty BW was similar in both LWG and LWL animals at all common slaughter weights because of the lesser and greater weights of the alimentary tract contents and the fleece, respectively, in the LWL animals. Carcass weight or dissected side weight was greater in LWL animals at each common slaughter weight but significantly so (P less than .05) at the 23.0 kg live weight only. Total side muscle weight was similar in LWG and LWL animals at each common slaughter weight, but the proportion of muscle in the dissected side weight was lower (P less than .05) in LWL animals at 23.0 kg live weight. Total side fat, subcutaneous fat, intermuscular fat, and kidney and channel fat weights were all greater in LWL animals at each common slaughter weight, but significantly so (P less than .05) at the 23.0 kg live weight only. Total side bone weight was higher at both 26.3 kg (P less than .01) and 23.0 kg (P less than .05) in the LWL animals. Weight loss in young sheep mobilized more weight of muscle than fat from the carcass, whereas bone weight was constant.

The effect of weight stasis on the dissected carcass composition of crossbred sheep

A study was made of the dissected carcass composition of crossbred wethers (progeny of Dorset Horn rams and Border Leicester x Merino ewes) maintained at 30 kg liveweight for either 0, 25, 50 or 75 days. Animals were individually penned and fed a pelleted ration of 80% lucerne chaff and 20% cereal grain (89.3% dry matter, I4.8To crude protein and 18.27 kJ/g gross energy). Cold carcass weight showed a significant increase (P &lt; 0.05) in animals during weight stasis, although dry matter intake of animals during weight stasis decreased. All dissected carcass fat depots increased during weight srasis, although only subcutaneous fat showed a significant increase (P &lt; 0.05) in weight. Neither the weight of total dissected side muscle nor total dissected side bone was affected by weight stasis. Only the weight of Standard muscle group 1 showed a significant response to weight stasis, and it increased (P &lt; 0-05). Weight stasis had no effect on the weights of separate bones. Results for fat, muscle and bone distribution are reported. Subcutaneous fat formed a significantly increasing proportion of total side fat weight (P &lt; 0.05) as duration of weight stasis increased, while intermuscular fat showed a trend to form a decreasing proportion. Weight stasis had no effect on the proportion of total side muscle formed by each of the Standard muscle groups, except group 4 which decreased (P &lt; 0.05). Bone distribution was not influenced by weight stasis.

Breed and sex effects on the development, distribution of muscle, fat and bone, and the partition of fat in pigs

SummaryDissection data from 341 carcasses collected over a period of 7 years at the Institute of Food Research, Bristol (Large White, 138 entire males and 112 females; Pietrain, 41 entire males and 31 females; Iron Age (European Wild Pig × Tamworth), 8 entire males and 11 females) were used to examine the growth of muscle, fat and bone in joints relative to the corresponding total tissue in the side, and the growth of the fat depots relative to total side fat.The musculature of Iron Age pigs was early maturing, as indicated by a particularly slow growth of pelvic limb and fast growth of neck and thorax muscles relative to total side muscle. As a consequence, Iron Age pigs had a lower percentage of pelvic limb and a higher percentage of neck and thorax muscles than the other breeds. Pietrains had proportionately the heaviest pelvic limb muscles, a result which was apparently independent of the overriding effect of maturity. However, considering the large difference in body shape (conformation) between Pietrain and Iron Age pigs, the differences in muscle weight distribution were small. Entire males had faster growing and heavier neck and thorax muscles than females. This was considered to be due to the effects of sex hormones. Entire males had proportionately less muscle in the pelvic limb.Within carcass fat, the order of increasing growth rate relative to total side fat was intermuscular fat &lt;; subcutaneous fat &lt;; perirenal-retroperitoneal fat. Pietrain and Iron Age pigs had higher relative growth rates for subcutaneous fat and lower relative growth rates for intermuscular fat than Large Whites, an indication of earlier maturity in carcass fat development. This was reflected in Iron Age pigs, but not Pietrains, in a particularly heavy weight of subcutaneous fat and light weight of intermuscular fat. Within the subcutaneous and intermuscular fat depots, the highest allometric growth coefficients were generally observed in the forequarter. There were no consistent breed effects on the distribution of subcutaneous fat whereas, in the intermuscular fat depot, Iron Age pigs had less fat in the earlier-maturing thoracic limb, and lumbar and abdominal joint. At the same weight of total side fat (8·80 kg), entire male Pietrains and Large Whites had more intermuscular and less subcutaneous fat than females. There was no sex difference in fat partition in Iron Age pigs.In all breeds, bone in the pelvic limb had the slowest relative growth. Similarly, the femur and the tibia-fibula were the two slowest growing bones of the four major limb bones examined. Otherwise, there was no consistent pattern of relative growth throughout the skeleton. Breed effects on relative growth within the skeleton and on bone distribution were small and considered to be of little commercial significance. Pietrains had the highest muscle: bone ratio in each of the four anatomical joints. Entire males and females had a similar relative growth and distribution of bones. Females had consistently higher muscle:bone ratios.

FAT GROWTH AND PARTITIONING AMONG THE DEPOTS IN DOUBLE MUSCLED AND NORMAL CATTLE

Eighteen Double Muscled (DM), 18 Beef Synthetic (SY) and 18 Hereford (HE) bulls were serially slaughtered from approximately 250 to 800 kg liveweight to determine the influence of maturity type and "double muscling" on fat growth, partitioning and distribution. The fatty tissue was dissected into subcutaneous fat (SCF), intermuscular fat (IMF) and carcass cavity fat (CCF); the sum of these depots was used as total side fat (TSF). Relative to TSF, DM did not differ significantly from the other maturity types in growth rates of SCF, IMF and CCF, but relative to fat percent in the side, DM tended to have much lower growth rates for SCF and CCF. The common growth coefficients indicated that as TSF increased the proportion of SCF increased (b &gt; 1; P &lt; 0.05), the proportion of IMF decreased (b &lt; 1; P &lt; 0.05), and the proportion of CCF remained relatively constant (b = 1; P &gt; 0.05). At equal TSF, as expected, HE tended to partition more of their fat to the subcutaneous depot, whereas DM and SY tended to partition more of their fat to the intermuscular and carcass cavity fat depots. Relative to HE, DM followed late-developing fat partitioning patterns. The hypodevelopment of fat depots in the carcasses of the muscular hypertrophied animals followed an inner-outer gradient which was most pronounced in the subcutaneous fat depot. Key words: Cattle, fat growth, double muscling, breed type

GROWTH PATTERNS OF MUSCLE, FAT AND BONE, AND CARCASS COMPOSITION OF DOUBLE MUSCLED AND NORMAL CATTLE

Eighteen Double Muscled (DM), 18 Beef Synthetic (SY) and 18 Hereford (HE) bulls were serially slaughtered from approximately 250 to 800 kg liveweight to determine the influence of maturity type and "double muscling" on tissue growth patterns and compositional differences which were examined by using the allometric equation Y = aXb after transformation to common logarithms (log10). As liveweight (LW) increased, the proportions of total side fat (TSF) and subcutaneous fat (SCF) increased, the proportions of total side muscle (TSM) and intermuscular fat (IMF) remained relatively constant and the proportion of total side bone (TSB) decreased. Relative to LW, DM had a similar growth rate for TSM and lower growth rates for TSF, SCF and IMF than HE and SY. All breed types had similar growth rates for TSB on LW. Relative to dissected side weight (DSW) and TSB, the DM bulls had a higher growth rate for TSM than did the HE and S Y bulls. Differences existed between DM and the more normal genotypes in carcass composition. DM was characterized by a high muscle:liveweight ratio, a high proportion of muscle in the carcass, high muscle:bone and muscle:fat ratios and a low proportion of fat compared to the more normal genotypes. Objective criteria to discriminate between HE and DM were SCF, muscle:bone and TSMTMF ratios, and between SY and DM were TSB and muscle:bone ratio. Key words: Beef bulls (young), growth patterns, carcass composition, double muscling, breed type

THE ACCUMULATION AND DISTRIBUTION OF FAT IN EWE AND RAM LAMBS

Sixteen ewes and 22 rams (crossbred lambs) were grouped by sex and fed a diet based on grain and hay. All animals were slaughtered over a 4-wk period to give a range of slaughter weights (24.0–61.8 kg). After slaughter, one side of each carcass was broken into the four primal wholesale cuts (leg, loin, rib, shoulder) with the rest of the carcass discarded as trim. The four wholesale cuts were separated into fat (subcutaneous fat (SF), intermuscular fat (IF), kidney fat (KF) and body cavity fat (BCF)) muscle and bone. Depot fat accretion in the carcass was investigated using the allometric equation with side weight and side fat weight as the independent variables. Total rate of fat deposition relative to side weight was higher in ewes than rams, and ewes had more total fat than rams when comparisons were made at the same side weight (10.03 kg). However, growth coefficients for depot fat accumulation in a side and in the wholesale cuts relative to side fat were homogeneous between sexes indicating that sex did not affect the relative accumulation of fat. SF, however, had the highest growth coefficient (1.23) and IF the lowest (0.74). At equal total side fat ewes had significantly more IF in a side than rams, but overall the differences in the distribution of fat in the wholesale cuts were minor and commercially unimportant. It was concluded that the ewes had a faster rate of fat deposition than rams but both sexes followed the same pattern of differential fat accumulation, and that the distribution of fat was dependent mainly on the total amount of fat in a carcass. Key words: Fat, lambs, carcass

Growth and development of water buffalo and Friesian cross-bred cattle, with special reference to body and carcass composition

SUMMARYA sample of twelve buffalo, nine O Friesian × ♀ Egyptian native Baladi (½ Friesian) and nine ♂ Friesian ×♀½ Friesian (¾ Friesian) bulls were individually penned and fed commercially cubed concentrates and roughages from weaning at 100 kg and slaughtered over the live-weight ranges 161–560 kg for buffaloes and 176–448 kg for cattle. Weights of gut fill (GFW), empty body (EBW), offals (TOW) and carcass were recorded. Right sides of all carcasses were jointed then dissected into muscle, fat, bone and ‘other tissues’. Analysis of covariance based on the allometric equationY=aXbwas applied to assess growth patterns (estimated from the slopes) and compositional differences (estimated from the intercepts).The effect of genotype-group was not statistically significant on EBW at the same fasted body weight and cold carcass weight at the same EBW. However, the buffalo empty body contained (P&lt; 0·05) more offal than the ¾ Friesian empty body and heavier TOW and lighter hot carcass than ½ Friesian empty body of the same weight.No significant genotype-group differences were found in the slope of the regression of weight of total side muscle (TSM), total side fat (TSF), subcutaneous fat, intermuscular fat and total side bone (TSB) on dissected side weight (DSW) and ½ EBW. Comparison of adjusted means, however, showed buffaloes to have significantly more TSF and TSB but less TSM than the Friesian cross-breds. Most of the difference in TSF was due to more subcutaneous fat in the buffaloes than in the Friesian cross-breds. In all comparisons the two Friesian cross-bred groups did not significantly differ from one another.The results indicate that Egyptian buffaloes may be earlier maturing than Friesian cross-bred cattle and buffaloes of other countries. It was also concluded that in order to produce desirable carcass of fat:muscle ratio of 1:5, Egyptian buffalo bulls should be slaughtered to produce carcasses of slightly more than 230 kg whereas ½ Friesian and ¾ Friesian bulls can be taken to heavier weights. Methods for reporting carcass compositional data are discussed.

ACCUMULATION OF LIPID IN RIB CUTS FROM BULL AND HEIFER CARCASSES OF TWO BREEDS

A trial is reported comparing the accumulation of lipid in rib cuts from 12 bull and 12 heifer carcasses from two breed types: Hereford (HE) and Dairy Synthetic (DY). Serial slaughter was carried out from weaning (163 ± 15.1 (SD) days) to approximately 16 mo of age. The left side of each carcass was broken in two quarters, and then eight wholesale cuts. Fat samples (subcutaneous, intermuscular, body cavity) and a muscle sample were taken from the rib cut and analyzed for their lipid and energy contents. The rate of accumulation of lipid was estimated from the growth coefficient, b, in the allometric equation (Y = aXb) using total separable fat as the independent variable. Growth coefficients were homogeneous both between breeds and sexes indicating that neither sex nor breed influenced the relative accumulation of lipid. A significant sex difference (P &lt; 0.01) was found when the lipid content of the fat depots and the rib muscle were adjusted to a constant side separable fat. No breed differences (P &gt; 0.05) were found in the lipid content of the fat depots. A significant difference between sexes was also found in the energy content of the fat depots, but no differences were found between breeds, when the data were adjusted to the mean of the total side fat.

FATTENING PATTERNS IN CATTLE. 2. FAT DISTRIBUTION AMONG THE WHOLESALE CUTS

A trial is reported comparing fat distribution in carcasses from bulls and heifers of two breed-types: Hereford (HE) and Dairy Synthetic (DY). Twelve bulls and twelve heifers of each breed were grouped four to a pen at weaning (163 ± 15.1 (SE) days), and serially slaughtered from that time to approximately 16 mo of age. After slaughter, one side of each carcass was broken into eight wholesale cuts, which were separated into fat (subcutaneous fat (SF), intermuscular fat (IF), and body cavity fat (BCF)), muscle and bone. Depot fat accretion in each cut was investigated using the allometric equation with side fat weight as the independent variable. Coefficients for SF were significantly higher in the rib, chuck and flank for HE carcasses than for DY carcasses and higher in the rib and flank for heifers than for bulls. At equal total side fat, HE carcasses had significantly more SF in the brisket and in the loin than DY animals. Heifers had significantly more fat in the loin than bulls. Differences among coefficients for IF relative to total fat were minor for both breed and sex. At equal total side fat, HE carcasses had less fat distributed intermuscularly than DY carcasses and had less IF in the brisket than heifers. The results are discussed in relation to the Canadian beef grading system.

EFFECTS OF BREED AND SEX ON THE PATTERNS OF FAT DEPOSITION AND DISTRIBUTION IN SWINE

The growth and distribution of fat from 163 pig carcasses were compared among five breeds (Duroc × Yorkshire (D × Y), Hampshire × Yorkshire (H × Y), Yorkshire (Y × Y), Yorkshire × Lacombe-Yorkshire (Y × L-Y) and Lacombe × Yorkshire (L × Y)) and two sex-types (barrows and gilts) over a wide range in carcass weight. The growth pattern of fat and the fat depots were estimated from the allometric equation (Y = aXb) using side muscle weight and side fat weight separately as independent variables. Growth coefficients (b) for intermuscular and subcutaneous fat depots were similar for the hindquarter but the intermuscular depot coefficient was slightly higher for the forequarter. The coefficient for body cavity fat was highest in all comparisons. No significant differences were detected for coefficients among breeds and between sexes using both total muscle and total side fat as independent variables. Significant breed and sex-type differences were found in the fat depots at a constant weight of side muscle. This would indicate that breed differences in fatness seemed to be more influenced by the initiation of fattening at different muscle weights than by any inherent differences in rate of fattening. Significant breed differences were also found in the fat depots at a constant fat weight, indicating that breed may influence fat distribution. Sex-type had no effect on fat distribution when the evaluation was made at constant fatness.

Effects of restrictions of energy, protein or both on growth and body composition of pigs

SummaryAn experiment was carried out, using Duroc Jersey barrows, to test the hypothesis that relationships within the pig fat-free carcass remain unaltered when varying the principal dietary factors: energy, protein or both. Twelve pigs were assigned to each of the following diets: high energy-high protein (HEHP), used as control group; low energy-high protein (LEHP); high energy-low protein (HELP) and low energy-low protein (LELP). From 30 kg live weight onwards the animals were individually penned and fed once a day the experimental rations, on a restricted scale of feeding related to live weight. Compared with the control group, daily intake of metabolizable energy was approximately 37% lower in LEHP and LELP groups while daily protein intake was approximately 25% lower in HELP and LELP groups.In each group the 12 pigs were slaughtered between 60 and 110 kg. The right half carcasses were completely dissected using strictly anatomical criteria. The main growth characteristics of the four treatments were described by second degree polynomials fitted to the live weight-age data. Each treatment produced a characteristic growth curve. In every case significant differences were found in the polynomial coefficients. Data on body composition were subjected to analysis of covariance, using the linear model y = a + bx. When growth of different parts of a whole were studied the weight of that whole was used as the independent variable. When muscle:bone ratio was examined the weight of total side muscle was used as covariate in the covariance analysis for total side bone.The major treatment effects were on the relationship between fat and non-fat tissues in the carcass. Thus, in relation to dissected side weight, HELP animals had more fat and less muscle and bone than controls, while LEHP and LELP pigs had more muscle and bone and less adipose tissue. Within the fat-free carcass several differences were found on muscle weight distribution. LEHP, HELP and LELP pigs had a higher proportion of ‘expensive muscles’. However, the magnitude of these changes was small and likely to be of little commercial importance. On the other hand, only minor differences were found in bone weight distribution. These were confined to the scapula and femur. Muscle:bone ratio was not affected by the treatments. Within the adipose tissue differences were observed in growth rates from the different depots relative to total side fat. Thus, it would appear that the growth rate of the subcutaneous depot was higher and that of the intermuscular one lower in LEHP and LELP animals. The body cavity depot was less in these animals.

Growth rate and its effect on empty body weight, carcass weight and dissected carcass composition of sheep

SummaryThe effect of three different growth rates from 15 to 40 kg live weight on the body composition of lambs was studied. The treatments were: High (H) ad-libitum feed intake, Low (L) restricted feed intake and High–Maintenance–High (HMH) ad-libitum feed intake from 15 to 25 kg followed by a 50-day period during which live weight was maintained constant, which in turn was followed by ad-libitum feeding. The animals were individually penned and fed a pelleted lucerne chaff-cereal grain mixture. Two animals were killed at the start of the experiment (15 kg) and the remaining 27 animals (nine in each treatment) were killed at common live weights of 25, 30, 35 and 40 kg. Analyses of covariance were used to compare linear regression equations representing results from each treatment using the logarithmic transformation of the allometric equation, y = axb.Animals in the H and L treatments had a mean growth rate from 15 kg until slaughter of 0·23 and 0·09 kg/day, respectively. From a live weight of 15 to 25 kg, the HMH group grew at a similar rate as the H group, viz. 0·22 and 0·21 kg/day, respectively. After the 50-day period of maintenance of live weight, the HMH animals killed at 30, 35 and 40 kg showed a marked compensatory growth response to ad-libitum feeding. These HMH animals had a mean growth rate of 0·37 kg/day compared with 0·26 kg/day for H animals over identical live-weight ranges.Empty body weight (EBW) formed a similar proportion of full body weight (FBW) in all three treatments. As a proportion of FBW, hot carcass weight (HCW) was similar in the H and L treatments, while at the 35 and 40 kg slaughter weights HCW was less in the HMH than in the H treatment. HCW also formed a lower proportion of EBW at the 35 and 40 kg slaughter weights in the HMH, than in both the H and L treatments. In the L treatment, HCW formed a greater proportion of EBW than in the H treatment, indicating a greater offal component of EBW in the H animals.The results of carcass dissection studies showed that, at the same dissected side weight (DSW), the amount of muscle, bone, connective tissue and total side fat (TSF) was similar in the three treatments. Although no differences were found between treatments in TSF, there were significant treatment effects on both the subcutaneous and inter-muscular fat depots. Animals in the H treatment had more and less, respectively, subcutaneous and intermuscular fat than the L animals. The amount of intermuscular fat was also greater in the HMH than in the H treatment.

Effects of three different growth rates on empty body weight, carcass weight and dissected carcass composition of cattle

SUMMARYA study was made of the effect on body composition of growing Angus steers from 300 to 440 kg at three different rates. The rates were: High (H) 0·8 kg/day, Low (L) 0·4 kg/day and High-Maintenance (HM) 0·8 kg/day followed by a period during which body weight was maintained constant.The animals were individually penned and the different growth rates were achieved by controlling intakes of a pelleted feed. Two animals (part of H treatment) were killed at 300 kg and the remaining 27 animals (nine in each treatment), were killed at common body weights of 330, 363, 400 and 440 kg.Analyses of covariance were used to compare linear regression equations representing results from each treatment. In order to do this, the logarithmic transformation of the allometric equation, y = axb, was used. As a proportion of empty body weight (EBW), hot carcass weight (HCW) was greater in both the HM and L groups than in the H group, indicating a greater offal component of EBW in the H animals. The loss in weight of the dressed carcass during storage at 2 °C for 24 h was similar in all three groups and was 0·98% of HCW. The proportions of HCW in the fore- and hind-quarters were similar in each group.At the same dissected side weight (DSW), the weight of bone was significantly greater in both the HM and L groups than in the H group indicating that bone development was related to both age and carcass weight. There were no significant differences between the groups in the proportions of either muscle or total fat. However, the proportion of kidney and channel fat in the H group was greater than in the HM and L groups and the proportion of subcutaneous fat was also greater in the H than in the L group. The amount of connective tissue in the three groups followed, in general, group differences in bone. Analyses of the dissected components of the separate fore- and hind-quarters showed that the difference between the H and L groups in the proportion of subcutaneous fat in the DSW was due to a relatively greater development of this fat in the fore-quarter of the H animals.No differences were found between treatments in the proportion of ‘expensive muscles’ relative to total side muscle (TSM). However, there were treatment effects on the proportions of TSM formed by certain groups of muscles; two examples are: the proportion of group 4 muscles (abdominal muscles) was higher and the proportion of group 6 muscles (distal muscles of the fore-leg) was lower in the H than in the L treatments. Bone weight distribution was similar in all treatments.There were differences between the H and HM groups in the relative growth ratios for all fat tissues (subcutaneous, intermuscular and kidney and channel fat) compared with total side fat. However, in the H and L groups, the relative growth ratios for corresponding fat categories were similar. The weight of kidney and channel fat in the left side of the carcass was significantly greater than in the right side of the carcass in all treatments.

Studies of fat distribution in the bovine carcass. I. The partition of fatty tissues between depots

(1) Total side fat (total dissected fat plus intramuscular fat) was examined in 23 bovine carcasses in four weight ranges. (2) The partition of fatty tissue between five depots revealed relative rises in intermuscular and subcutaneous depots and relative declines in intramuscular, kidney, and channel fats with increasing carcass weight. (3) Intermuscular and subcutaneous fats reached high levels relative to total side fat at different stages. Intermuscular fat rose quickly to c. 45.0% of total side fat at about 2.0 kg total side fat (c. 56 days) whilst subcutaneous fat reached 29.0% at c. 13.0 kg total side fat (c. 270 days). (4) Intramuscular fat did not show an increase relative to total side fat as carcass weight increased. Its contribution to total fat was greatest in the lightest sides and reached a minimal value at c. 13.0 kg total side fat, which it maintained thereafter. (5) All regressions of the weight of five fat depots on total side fat were highly significant (P &lt; 0.01). (6) There appears to be a need for precise definition of fat distribution patterns in breeds and strains of cattle in order that carcasses of optimum composition might be produced.