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In Japan, Korea, the USA, and Australia, the area of the “muscle eye” (cross-section of the M. longissimus dorsi during the division of the half-carcass between the 12th and 13th rib into the front and rear parts) is used to assess the quality of cattle carcasses. The correlation between this feature and the slaughter and quality characteristics of carcasses in 20-22-month-old crossbred bulls (Ukrainian Black-and-White Dairy × Holstein) has been studied. The area of the “muscle eye” in bulls was determined before slaughter by an ultrasound analyzer Emperor 860. After slaughter, it was calculated by the length and depth of the "muscle eye". The colour of muscle and adipose tissue, carcass conformation, development, and subcutaneous fat thickness have been examined. The correlation between the size of the "muscle eye" and carcasses' quantitative and qualitative characteristics has been determined. The area of the "muscle eye" has a positive relationship (r = 0.612; p >0.999) with live weight after fasting, carcass weight (r = 0.598; p >0.999), flesh weight (r = 0.498; p >0.99), including the highest (r = 0.745; p >0.999), and first grade (r = 0.662; p >0.99), the amount of adipose tissue (r = 0.491; p >0.99) and tendons and ligaments (r = 0.435; p >0.99). With its increase, there is a tendency to an inverse relationship with the content of second-grade flesh in the carcass (r = 0.303), carcass conformation (r = 0.147), fat-irrigation thickness (r = 0.125), and marbling (r = 0.340). The area of the "muscle eye" is inversely correlated with the development of subcutaneous fat (r = -0.389; p >0.95) and the saturated colour of muscle tissue (r = -0.309). The correlation coefficients between the area of the "muscle eye" determined by ultrasound and quantitative and qualitative characteristics of carcasses are significantly higher than those obtained by post-slaughter calculation of the area of the muscle eye by measuring the length and depth. The data's practical significance is obtaining knowledge that allows beef to be sorted based on the correlation between the muscle eye area and the quality of carcasses and beef.

In Japan, Korea, the USA, and Australia, the area of the "muscle eye" (cross-section of the M. longissimus dorsi during the division of the half-carcass between the 12th and 13th rib into the front and rear parts) is used to assess the quality of cattle carcasses. The correlation between this feature and the slaughter and quality characteristics of carcasses in 20-22-month-old crossbred bulls (Ukrainian Black-and-White Dairy x Holstein) has been studied. The area of the "muscle eye" in bulls was determined before slaughter by an ultrasound analyzer Emperor 860. After slaughter, it was calculated by the length and depth of the "muscle eye". The colour of muscle and adipose tissue, carcass conformation, development, and subcutaneous fat thickness have been examined. The correlation between the size of the "muscle eye" and carcasses' quantitative and qualitative characteristics has been determined. The area of the "muscle eye" has a positive relationship (r = 0.612; p >0.999) with live weight after fasting, carcass weight (r = 0.598; p >0.999), flesh weight (r = 0.498; p >0.99), including the highest (r = 0.745; p >0.999), and first grade (r = 0.662; p >0.99), the amount of adipose tissue (r = 0.491; p >0.99) and tendons and ligaments (r = 0.435; p >0.99). With its increase, there is a tendency to an inverse relationship with the content of second-grade flesh in the carcass (r = 0.303), carcass conformation (r = 0.147), fat-irrigation thickness (r = 0.125), and marbling (r = 0.340). The area of the "muscle eye" is inversely correlated with the development of subcutaneous fat (r = -0.389; p >0.95) and the saturated colour of muscle tissue (r = -0.309). The correlation coefficients between the area of the "muscle eye" determined by ultrasound and quantitative and qualitative characteristics of carcasses are significantly higher than those obtained by post-slaughter calculation of the area of the muscle eye by measuring the length and depth. The data's practical significance is obtaining knowledge that allows beef to be sorted based on the correlation between the muscle eye area and the quality of carcasses and beef. [ABSTRACT FROM AUTHOR]

Considering the additional market value of pasture meat, many authentication methods were developed to discriminate it from meat produced in conventional systems. The visible reflectance spectroscopy technique has proved its efficiency under European conditions and breeds. The present study tested the reliability of this method to discriminate between pasture-fed (P) and stall-fed (S) lambs under North African conditions and investigated the effect of feeding system (FS) (P v. S) and breed (Barbarine; Queue Fine de l’Ouest; and Noire de Thibar) on weight and colour of perirenal, subcutaneous and caudal fat. A total of 18 P and 18 S lambs were used with 6 P and 6 S lambs for each breed. The colour and the reflectance spectrum of different fat tissues were measured. The FS affected weights of all fat tissues and all colour parameters of perirenal and subcutaneous fat (P ≤ 0.01); it almost affected redness and yellowness of caudal fat (P ≤ 0.05; P ≤ 0.01). In all adipose tissues, lightness was higher and both redness and yellowness were lower for S lambs than P lambs. The breed affected weight, lightness and redness of perirenal fat and weight and redness of subcutaneous fat with significant interaction with FS for subcutaneous fat data. To discriminate P lambs from S lambs, the reflectance spectrum of perirenal, subcutaneous and caudal fat at wavelengths between 450 and 510 nm (Method 1, M1) or at wavelengths between 400 and 700 nm using partial least squares discriminative analysis as a classification method (Method 2, M2) were used. M2 yielded to a higher proportion of correctly classified lambs compared with M1 (P = 0.001). The proportion of correctly classified lambs using M2 was 76.4, 75.0 and 80.0% for perirenal, subcutaneous and caudal fat for P lambs and 83.3, 76.4 and 100.0% for S lambs. Despite lower reliability in comparisons to European researches, this study confirmed the efficiency of visible reflectance spectroscopy technique applied on perirenal fat in feeding systems authentication under North African conditions and spotted the caudal fat as a new support for better classification of fat-tailed breeds.

Considering the additional market value of pasture meat, many authentication methods were developed to discriminate it from meat produced in conventional systems. The visible reflectance spectroscopy technique has proved its efficiency under European conditions and breeds. The present study tested the reliability of this method to discriminate between pasture-fed (P) and stall-fed (S) lambs under North African conditions and investigated the effect of feeding system (FS) (P v. S) and breed (Barbarine; Queue Fine de l'Ouest; and Noire de Thibar) on weight and colour of perirenal, subcutaneous and caudal fat. A total of 18 P and 18 S lambs were used with 6 P and 6 S lambs for each breed. The colour and the reflectance spectrum of different fat tissues were measured. The FS affected weights of all fat tissues and all colour parameters of perirenal and subcutaneous fat (P ≤ 0.01); it almost affected redness and yellowness of caudal fat (P ≤ 0.05; P ≤ 0.01). In all adipose tissues, lightness was higher and both redness and yellowness were lower for S lambs than P lambs. The breed affected weight, lightness and redness of perirenal fat and weight and redness of subcutaneous fat with significant interaction with FS for subcutaneous fat data. To discriminate P lambs from S lambs, the reflectance spectrum of perirenal, subcutaneous and caudal fat at wavelengths between 450 and 510 nm (Method 1, M1) or at wavelengths between 400 and 700 nm using partial least squares discriminative analysis as a classification method (Method 2, M2) were used. M2 yielded to a higher proportion of correctly classified lambs compared with M1 (P = 0.001). The proportion of correctly classified lambs using M2 was 76.4, 75.0 and 80.0% for perirenal, subcutaneous and caudal fat for P lambs and 83.3, 76.4 and 100.0% for S lambs. Despite lower reliability in comparisons to European researches, this study confirmed the efficiency of visible reflectance spectroscopy technique applied on perirenal fat in feeding systems authentication under North African conditions and spotted the caudal fat as a new support for better classification of fat-tailed breeds. [ABSTRACT FROM AUTHOR]

Bull beef production is traditionally based on high concentrate rations fed indoors. Inclusion of grazed grass, which is generally a cheaper feed, would decrease the cost of bull beef production, but may affect beef quality. Accordingly, the organoleptic quality and composition of beef from continental-sired suckler bulls (n=126) assigned to either ad libitum concentrates to slaughter (C), grass silage (GS) ad libitum for 120 days followed by C (GSC) or GS followed by 100 days at pasture and then C (GSPC) and slaughtered at target carcass weights (CW) of 360, 410 or 460 kg was examined. Tenderness, flavour liking and overall liking were lower (P

The studies of meat and fat colour and marbling in Longissimus dorsi of different cattle — beef-producing (Aberdeen-Angus,Herefordbreeds) and dual-purpose (Simmental, Black-and-white breeds) — allowed to define groups by the colour values according to Lab international colour model. Measurements were performed 24 hours post-mortem between 12th and 13th ribs. It was found that different ranges of meat colour differed primarily in L* (lightness) and a* (redness) values, while b* (yellowness) values did not significantly differ. The highest differentiation between ranges of fat colour was noted in b* values, whereas L* and a* slightly differed. Moreover, visual assessment of beef marbling by four grades (small, moderate, good, and rich) and instrumental (microstructural) analysis using a computer image analysis system were carried out. The morphometric study of marbling was conducted in accordance with the principles of system quantitative analysis. To perform quantitative measurements, object analysis parameters (area) were specified. Both automatic and manual measurements of specified parameters were used. The study of Longissimus dorsi marbling established high agreement between visual and instrumental evaluations of marbling.

BACKGROUND The interest for grazing systems and the use of condensed tannins (CTs) as sources of natural antioxidants in animal diets has been increasing in recent years. The objective was to study the animal performance and carcass quality of the lambs according to the feeding strategy during lactation (indoors, grazing alfalfa, grazing sainfoin) and the inclusion of quebracho as a source of CTs (50 g kg−1) in the fattening concentrate. RESULTS: The feeding strategy during lactation only had effects on carcass quality. Indoor lambs had a greater dressing percentage and deposition of kidney fat than sainfoin and alfalfa lambs. The kidney fat of sainfoin‐ and alfalfa‐fed lambs had a greater yellowness, chroma and carotenoid content than the fat of indoor‐fed lambs (P < 0.05), whereas the subcutaneous fat colour was not affected by the feeding during lactation. The use of fat colour to trace the feeding strategy was assessed and found insufficiently accurate to implement its use. The inclusion of 50 g kg−1 quebracho in the concentrate fed during the fattening period increased lamb weight gains and feed intake but had little effect on the carcass characteristics. CONCLUSIONS: The feeding strategies during lactation had an effect on the carcass characteristics, highlighting the importance of the dam's diet during this period. The inclusion of quebracho in the lamb's concentrate had minor effects. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Fat is one of the most important traits determining the quality of pork. The composition of the fat greatly influences the quality of pork and its processed products, and contribute to defining the overall carcass value. However, establishing an efficient method for assessing fat quality parameters such as fatty acid composition, solid fat content, oxidative stability, iodine value, and fat color, remains a challenge that must be addressed. Conventional methods such as visual inspection, mechanical methods, and chemical methods are used off the production line, which often results in an inaccurate representation of the process because the dynamics are lost due to the time required to perform the analysis. Consequently, rapid, and non-destructive alternative methods are needed. In this paper, the traditional fat quality assessment techniques are discussed with emphasis on spectroscopic techniques as an alternative. Potential spectroscopic techniques include infrared spectroscopy, nuclear magnetic resonance and Raman spectroscopy. Hyperspectral imaging as an emerging advanced spectroscopy-based technology is introduced and discussed for the recent development of assessment for fat quality attributes. All techniques are described in terms of their operating principles and the research advances involving their application for pork fat quality parameters. Future trends for the non-destructive spectroscopic techniques are also discussed. [ABSTRACT FROM AUTHOR]

Subcutaneous fat from Norwegian Landrace (n = 3230) and Duroc (n = 1769) pigs was sampled to investigate the sources of variation and genetic parameters of various fatty acids, fat moisture percentage and fat colour, with the lean meat percentage (LMP) also included as a trait representing the leanness of the pig. The pigs were from half-sib groups of station-tested boars included in the Norwegian pig breeding scheme. They were fed ad libitum to obtain an average of 113 kg live weight. Near-infrared spectroscopy (NIRS) was applied for prediction of the fatty acids and fat moisture percentage, and Minolta was used for the fat colour measurements. Heritabilities and genetic correlations were estimated with a multi-trait animal model using average information-restricted maximum likelihood (AI-REML) methodology. Fat from Landrace pigs had considerably more monounsaturated fatty acids, polyunsaturated fatty acids (PUFAs) and fat moisture, as well as less saturated fatty acids (SFAs) than fat from Duroc pigs. The heritability estimates (s.e. 0.03 to 0.08) for the various fatty acids were as follows: Palmitic, C16:0 (0.39 and 0.51 for Landrace and Duroc pigs, respectively); Palmitoleic, C16:1n-7 (0.41 and 0.50); Steric, C18:0 (0.46 and 0.54); Oleic, C18:1n-9 (0.67 and 0.57); Linoleic, C18:2n-6 (0.44 and 0.46); α-linolenic, C18:3n-3 (0.37 and 0.25) and n-6/n-3 ratio (0.06 and 0.01). The other fat quality traits revealed the following heritabilities: fat moisture (0.28 and 0.33), colour values in subcutaneous fat: L* (whiteness; 0.22 and 0.21), a* (redness; 0.13 and 0.24) and b* (yellowness; 0.07 and 0.17) and LMP (0.46 and 0.47). LMP showed high positive genetic correlations to PUFA (C18:2n-6 and C18:3n-3), which implies that selecting leaner pigs changes the fatty acid composition and deteriorates the quality of fat. Higher concentrations of PUFA are not beneficial as the ratio of n-6 and n-3 fatty acids becomes unfavourably high. Owing to the high genetic correlation between C18:2n-6 and C18:3n-3 and a low heritability for this ratio, the latter is difficult to change through selection. However, a small reduction in the ratio should be expected if selection aims at reducing the level of C18:2n-6. Selection for more C18:1n-9 is possible in view of the genetic parameters, which are favourable for eating quality, technological quality and human nutrition. The NIRS technology and the high heritabilities found in this study make it possible to implement fat quality traits to achieve the breeding goal in the selection of a lean pig with better fat quality.

Bull beef production is traditionally based on high concentrate rations fed indoors. Inclusion of grazed grass, which is generally a cheaper feed, would decrease the cost of bull beef production, but may affect beef quality. Accordingly, the organoleptic quality and composition of beef from continental-sired suckler bulls (n=126) assigned to either ad libitum concentrates to slaughter (C), grass silage (GS) ad libitum for 120 days followed by C (GSC) or GS followed by 100 days at pasture and then C (GSPC) and slaughtered at target carcass weights (CW) of 360, 410 or 460 kg was examined. Tenderness, flavour liking and overall liking were lower (P<0.05) for GSPC than for C and GSC. Intramuscular fat content and soluble collagen proportion were lower (P<0.05) for GSPC than GSC which was lower (P<0.05) than C. Soluble collagen proportion was lower (P<0.05) for 460 kg than 410 kg CW, which was lower (P<0.05) than 360 kg CW. Inclusion of a grazing period decreased the ratings of tenderness, flavour liking and overall liking, but age of the bulls at slaughter had no clear influence on sensory characteristics. [ABSTRACT FROM PUBLISHER]

Despite the heavy reliance of the New Zealand beef industry on animals produced from the dairy industry (predominantly Friesian and Friesian cross), there is a widespread belief that beef of dairy origin is inferior to beef produced from traditional ‘British’ breeds. This belief is not supported by the scientific literature. There is a large body of work that suggests there is no difference between dairy and traditional British beef breeds in growth potential, lean meat yield, yield of prime cuts, and the quality of meat produced when grazed under similar conditions and slaughtered at the same chronological age or the same level of maturity (fatness). The current New Zealand payment schedule based on carcass weight, fatness and muscularity, undervalues dairy carcasses for having a different pattern of fat distribution (i.e. less subcutaneous fat) and a different muscle shape (poorer conformation score). In New Zealand, the key commercial driver for using traditional beef-bred cattle appears to be their ability to achieve the 3 mm minimum fat depth and therefore a prime-graded carcass at a lighter carcass weight and with a younger animal compared to dairy-bred cattle. [ABSTRACT FROM PUBLISHER]

Abstract: The effect of type of silage offered to beef heifers during the finishing period on aspects of beef quality was determined. In two experiments, a diet based on grass silage (GS) was compared with a diet based on maize silage (MS) or whole-crop wheat silage (WCW). Compared to the GS-based diet, increasing the amount of MS linearly increased fat whiteness while the increase in fat whiteness due to WCW was dependent on the stage of crop maturity at harvesting. There was no effect of diet on muscle colour or on muscle pH measured at 48h post-mortem, drip loss, taste panel traits after 14days ageing or shear force values at 2, 7 or 14days ageing. The alternative silages decreased the n−3 polyunsaturated fatty acid proportion and increased the linoleic:linolenic acid ratio in intramuscular lipid. It is concluded that type of silage affects fat colour and fatty acid composition of muscle but not the other muscle characteristics examined. [Copyright &y& Elsevier]

Abstract: The effect of the diet offered to heifer progeny of a grassland-based spring calving suckler beef production system during the finishing period on the colour of carcass fat and the colour and sensory characteristics of longissimus thoracis et lumborum muscle was determined in the context of suitability for one sector of the Italian beef market. A diet based on grass silage plus concentrate was compared with a diet based on concentrates and wheat straw. Compared to animals offered the concentrate-based diet both the kidney/channel fat and subcutaneous fat from animals offered the grass silage based diet was more yellow and a greater proportion (33 v 0%) were deemed unacceptable for this market on the basis of fat colour. There was no effect of diet on muscle colour or on muscle pH, drip loss, taste panel traits or shear force values or on market acceptability based on muscle colour. The maximum level of dietary inclusion of grass silage to avoid inadequate fat colour remains to be determined. [Copyright &y& Elsevier]

Abstract: The aim of the study was evaluate the use of forage diets (grazing pasture vs. hay) around ewe parturition on the performance and meat quality of suckling lambs (10–12kg body-weight). Forty-eight multiparous single bearing ewes from the Churra Tensina breed were used. The experimental treatments were conducted during the last 5 weeks of pregnancy (pre-partum period) and the 5 weeks of lactation (post-partum period) in a 2×2 factorial design. Ewes were fed ad libitum on mountain pastures or pasture hay. Hay was made in late spring from the same pasture paddocks to those grazed in autumn. Results showed that ewes body-weight (BW) and body condition score (BCS) were not affected by forage type feed around ewe parturition. The week post-partum had a more determinant effect on milk production and composition than forage type pre- and post-partum. The energy-corrected milk yield peaked on first week of lactation (1.39l/day, P <0.05), and decreased significantly from week 3 post-partum onwards (1.29l/day vs. 1.02l/day, P <0.05). Forage type supplied to ewes during the pre-partum period did not affect any of the studied variables on lambs. During post-partum period forage type had effect on lamb ADG, which was higher in grazing system than in hay feed (259g/day vs. 220g/day). Consequently, age at slaughter was greater in lambs raised by ewes receiving hay post-partum compared to grazing ewes (36 days vs. 32 days, P <0.05). Caudal fat colour was affected only by post-partum forage type, showing grazing group greater redness, yellowness and absolute value of the integral of the translated spectrum (SUM) than that forage type (P <0.05). Carcasses from lambs raised by post-partum grazing ewes led to a muscle with lower lightness and yellowness and greater redness than hay forage type (P <0.05). Lambs whose dams grazed presented a higher visual appraisal score at cutting time, however these differences disappeared as time advanced. Grazing forage had a positive effect on consumer purchasing decision (P <0.10). In conclusion, forage type in pre-partum period did not affect the studied parameters whereas ewes grazing on mountain pastures after autumn-lambing improved lamb performance without any detrimental effect on carcass and instrumental meat quality. [Copyright &y& Elsevier]

Abstract: Two experiments with 72 slaughter pigs in each were conducted. Entire males and females were individually fed restricted. Palm kernel-, soybean- and fish-oil were used in varying combinations, giving different dietary fat levels (29–80g/kg) and iodine values ranging from 50 to 131. Shoulder fat was analysed for fatty acid composition (inner and outer layer), firmness and colour. A clear dose–response relationship was seen between fatty acids in diets and in shoulder fat. Interestingly, the very long chain n-3 fatty acids seemed to be deposited more efficiently when additional fat was included in the diet. Both high and low dietary iodine values changed towards less extreme iodine values in fat. Low-fat diets enhanced de novo synthesis of fatty acids. Males revealed a higher percentage of PUFA and a lower percentage of C18:1 and MUFA. Fat firmness, but not colour, was influenced by sex and dietary fat source. [Copyright &y& Elsevier]

Abstract: One hundred and twenty-seven lambs were fed as follows: lambs and dams grazing alfalfa (Gr); the same as Gr but lambs had access to concentrate (Gr+S); ewes grazed and lambs received milk and concentrate until weaning and thereafter concentrate and straw (Rat-Gr); ewes and lambs were stall-fed (Ind). Lambs were slaughtered at 22–24kg live weight and fat and M. rectus abdominis colour was measured instrumentally and subjectively. The evolution of the instrumental colour and texture of M. longissimus lumborum was also recorded. There were significant differences in the instrumental colour of subcutaneous fat amongst feeding systems, but no differences were observed upon visual appraisal. On average, M. rectus abdominis colour in the four feeding systems was classed as pink. Differences in longissimus thoracis colour at 0h disappeared at 24h of air exposure and there were no differences in pH or cooking losses. At no time were any differences in instrumental texture found. [Copyright &y& Elsevier]

β, β-carotene-9′, 10′-dioxygenase (BCO2) plays a role in cleaving β-carotene eccentrically, and may be involved in the control of adipose and milk colour in cattle. The bovine BCO2 gene was sequenced as a potential candidate gene for a beef fat colour QTL on chromosome (BTA) 15. A single nucleotide base change located in exon 3 causes the substitution of a stop codon (encoded by the A allele) for tryptophan80 (encoded by the G allele) (c. 240G>A, p.Trp80stop, referred to herein as SNP W80X). Association analysis showed significant differences in subcutaneous fat colour and beta-carotene concentration amongst cattle with different BCO2 genotypes. Animals with the BCO2 AA genotype had more yellow beef fat and a higher beta-carotene concentration in adipose tissues than those with the GA or GG genotype. QTL mapping analysis with the BCO2 SNP W80X fitted as a fixed effect confirmed that this SNP is likely to represent the quantitative trait nucleotide (QTN) for the fat colour-related traits on BTA 15. Moreover, animals with the AA genotype had yellower milk colour and a higher concentration of beta-carotene in the milk. [ABSTRACT FROM AUTHOR]

Abstract: Steers were offered grass silage ad libitum and 6.4 kg concentrates daily for 126 days or silage ad libitum for 35 days, followed by concentrates ad libitum (Experiment 1). Steers were offered grass silage ad libitum and 6 kg concentrates daily for 154 days, concentrates ad libitum or grass silage ad libitum for 112 days followed by concentrates ad libitum (Experiment 2). All treatments received the same total concentrate allowance. In Experiment 1, there was no difference in any measurement of meat quality. In Experiment 2, ad libitum concentrate feeding per se, decreased redness and increased shear force of muscle at 2 days post-mortem. Delaying concentrate feeding decreased fat yellowness, decreased shear force at 7 and 14 days post-mortem and increased muscle redness at 14 days post-mortem. Modifications of the beef production system examined had minor effects on beef quality which are unlikely to be of commercial significance. [Copyright &y& Elsevier]

Abstract: The objective of the present study was to elucidate the significance of a muscle-glycogen-reducing finishing diet containing a high ratio of rapeseed and grass meal on fat colour and pork colour compared with a control diet. Pork colour was determined as the extent of blooming of M. longissimus dorsi (LD) and M. semimembranosus (SM) after 1, 2, 4, 8 and 15 days of aging, while fat colour was measured on back fat and stripped bacon the day after slaughter. The muscle-glycogen-reducing diet significantly decreased the glycogen content measured 1min after slaughter in LD. This was reflected as decrease in early post-mortem temperature, as well as a tendency to higher initial pH in both muscles. Moreover ultimate pH was significantly higher in LD from strategically fed pigs compared to the control group and the same tendency was found in SM. Independent of muscle and time of aging, the colour of bloomed pork from pigs fed the control diet had higher chroma and L ∗, a ∗ and b ∗ values compared with pork from the pigs fed the muscle-glycogen-reducing diet with the effect being most pronounced in LD. This can be explained by the slightly higher pH45min in the muscles from the pigs fed the muscle-glycogen-reducing finishing diet, which sustain the metmyoglobin reductase activity and the oxygen consumption potential in the muscle and hereby minimise the degree of blooming. The more pronounced influence of the experimental diet on the degree of blooming in LD compared to SM may be explained by the lower T 45min in LD, which minimise denaturation of the enzymatic processes. This clearly shows that the diet composition can be used to control the extent of blooming in pork. Finally, despite the high content of grass meal in the muscle-glycogen-reducing finishing diet, this diet had negligible influence on the colour of the back fat and stripped bacon fat. [Copyright &y& Elsevier]