The effect of supplementation with expanded sunflower seed on carcass and meat quality of lambs raised on pasture

The use of conventional concentrates in the supplementation of grass-based fed lambs may induce improvements in growth performance and/or carcass quality but may be disadvantageous in fatty acid profile of tissues, with a negative impact in some nutritional indexes. The objective of this trial was to evaluate the effects on growth performance, carcass and meat quality of using unprotected, unsaturated fat as a supplement for grass-fed based lambs. Twenty-four Merino Branco ram lambs raised on pasture, were supplemented with corn whole grain plus sunflower meal or corn whole grain plus expanded sunflower seed, from 20 to 30 kg live weight. The supplement had no effects on growth performance, carcass quality traits, or meat pH, colour estimates (L^*, a^*, b^*), water-holding capacity, shear force and sensorial attributes. However, lambs supplemented with expanded sunflower seed showed higher proportions of cis-9, trans-11 octadecadienoic acid and trans-vaccenic acid in intramuscular and subcutaneous fat, showing that the inclusion of unprotected lipids in lambs diet was effective in preventing the reduction of rumenic acid (C18:2 cis-9, trans-11) that occurs when conventional concentrates are used as a supplement.     

Phenotypic blood glutathione concentration and selenium supplementation interactions on meat colour stability and fatty acid concentrations in Merino lambs

The interaction between blood glutathione (GSH) and supplementation of selenium (Se, 2.5 mg/kg diet) on meat colour and fatty acids concentrations was studied. Forty eight Merino lambs selected for high blood GSH (HGSH) or low GSH (LGSH) concentration were used. They were fed individually with or without Se supplement for 8 weeks. There were interactions (P<0.05) between GSH and Se on the colour stability (as w630 nm/w580 nm ratio) of m. longissimus (LD), m. semimembranosus (SM) and m. semitendinosus. Without Se supplementation the ratio was higher in HGSH than LGSH group. However, the difference was reduced with Se supplement. Polyunsaturated and n-3 fatty acids in SM and LD were higher in HGSH than in LGSH group (P<0.05), and did not change with Se supplement. Se supplementation increased Se content in LD (P<0.001) and the lungs (P<0.05), but had no influence in the heart.     

Effect of suckling management on productive performance,carcass traits and meat quality of Comisana lambs

The effect of restricted suckling on productive performance, carcass traits, meat quality and skeletal development of growing lambs was studied. Twenty-one naturally suckled male Comisana lambs were divided into three equal weight groups differing in suckling management systems: (1) only maternal milk (C); (2) only maternal milk until 15th day of age, and then, till slaughter, maternal milk, concentrate and Lucerne hay ad libitum (T1); (3) only maternal milk until 15th day of age, and then from 16th to 30th days of age, maternal milk, concentrate and Lucerne hay ad libitum, and, from 31st day of age till slaughter, only concentrate and Lucerne hay ad libitum (T2). The total mean milk yield was 22.7 and 41.6 kg per ewe for T1 and T2, respectively. Restricted suckling did not significantly affect slaughter weight, hot and cold carcass weights, carcass shrink losses, pH, colour and area of Longissimus muscle, pelvic limb, or bone characteristics. Suckling management system significantly affected ADG, milk intake, dressing percentage, and percentages of intestine, stomach, offal, kidney fat, shoulder, lean and fat, and there were differences in total collagen, and hydroxylysylpyridinoline crosslink concentrations. In addition, different IMC maturity among the muscles was apparent.     

Effects of suckling length (45, 75 and 120 d) and rearing type on cortisol level, carcass and meat quality characteristics in Kivircik lambs

Forty lambs were used to investigate effects of suckling length and rearing type (single and twin) on welfare parameters, carcass and meat quality characteristics. SC-45 and SC-75 lambs were weaned at 45-d and 75-d of age, respectively, whereas SC-120 lambs were not weaned until slaughter age of 120-d. The elevated cortisol concentration due to weaning stress returned to pre-weaning level at 2-d after weaning. SC-120 lambs had higher daily gain, plasma cortisol and glucose levels at exsanguination, hot carcass weight, dressing percentage and fatness score than weaned lambs. Suckling length did not influence instrumental meat quality characteristics, except shear force. SC-45 lambs had tougher meat than other groups according to instrumental and sensory analyses. SC-75 and SC-120 lambs had similar meat shear force value and sensory scores. Single lambs had higher daily gain, and greater scores for carcass characteristics and sensory evaluation, and lower pH(24) and shear force than twin lambs.     

Influence of dietary selenium and vitamin E on quality of veal

Three groups of six calves each were fed a milk replacer and a starter concentrate for 15weeks. Calves of the first group received the basal diet containing selenium (Se) and vitamin E at 0.095-0.128mg and 30-33mg per kg of total solids, respectively. Calves of the second group received the basal diet supplemented with Se-enriched yeast to increase dietary Se concentration to 0.50mg/kg. The third group of calves received the latter diet supplemented with vitamin E to increase its concentration to 100mg/kg. There was no effect of diet on growth rate, digestibility of dry matter and Se, chemical composition of meat (M. Longissimus thoracis et lumborum), meat colour and fatty acid profile of meat lipids. The Se supplementation significantly increased Se concentration in muscle from 0.21 to 0.43mg/kg. The activity of glutathione peroxidase (GSH-Px) in muscle and liver tissue of Se-supplemented animals was increased by 56% and 67%, respectively, compared to the control. The combined supplementation of vitamin E and Se significantly improved the lipid stability of meat compared to the control diet, but not compared to the Se-supplemented diet. It can be concluded that dietary Se supplementation increases the concentration of Se and the GSH-Px activity in meat, but has limited potential for improving meat oxidative stability.     

Effects of previous diet and duration of soybean oil supplementation on light lambs carcass composition, meat quality and fatty acid composition

Forty Merino Branco ram lambs were used to study the effects of initial diet and duration of supplementation with a conjugated linoleic acid (CLA) promoting diet, on carcass composition, meat quality and fatty acid composition of intramuscular fat. The experimental period was 6 weeks. The experimental design involved 2 initial diets (commercial concentrate (C); dehydrated lucerne (L)), and 2 finishing periods (2 and 4 weeks) on dehydrated lucerne plus 10% soybean oil (O). Data were analysed as a 2 × 2 factorial arrangement with initial diet and time on finishing (CLA promoting) diet as the main factors. The lambs were randomly assigned to four groups: CCO; COO; LLO; LOO according to the lamb’s diet fed in each period.Lambs initially fed with concentrate showed higher hot carcass weights (11.2 vs 9.6 kg) than lambs fed initially with lucerne. The increase of the duration of finishing period reduced the carcass muscle percentage (57.4% vs 55.5%) and increased the subcutaneous fat percentage (5.67% vs 7.03%). Meat colour was affected by initial diet. Lambs initially fed with concentrate showed a lower proportion of CLA (18:2cis-9, trans-11 isomer) (0.98% vs 1.38% of total fatty acids) and most of n−3 polyunsaturated fatty acids than lambs initially fed with lucerne. Initial diet did not compromise the response to the CLA-promoting diet and the proportion of 18:2cis-9, trans-11 in intramuscular fat increased with the duration of time on the CLA-promoting diet (1.02% vs 1.34% of total fatty acids).     

Effect of production system on carcass measurements and meat quality of Kivircik lambs

Effect of production system on carcass and meat quality was investigated in four groups of lambs: i. W-C lambs were weaned between 45 and 60 days of age and then were fattened with concentrate feed until slaughter; ii. W-G-S lambs were weaned and then taken to pasture and wheat stubble; iii. UW-C lambs were fattened with concentrate feed and they suckled their dams until slaughter; iv. UW-G lambs were kept with their dams and were taken to pasture in the day-time. Hot carcass weight was 13.62, 12.52, 14.37 and 13.88 kg (P < 0.001), and dressing percentage was 55.24, 51.77, 57.83 and 55.38% (P < 0.001), for W-C, W-G-S, UW-C and UW-G lambs, respectively. Ultimate meat pH was higher in W-G-S lambs than lambs from W-C and UW-C systems (P < 0.05). W-G-S lambs had higher shear force value in longissimus dorsi muscle (P < 0.05) and lower meat lightness (P < 0.001) than those of other systems. Panellists gave the lowest sensory scores, except juiciness, to meat of W-G-S lambs.     

Effects of genotype, level of supplementation, and organic chromium on growth performance, carcass, and meat traits grazing lambs

The aim of the present study was to evaluate the effects of Suffolk×Dorper (SD) and Rambouillet (R) lamb genotypes, dietary supplementation, and organic chromium on growth performance, carcass, and meat traits in male lambs grazing ryegrass pasture. SD lambs had heavier cold carcass (HCW) and better carcass yield (CY) and rib eye area at 12th rib (RA) than R lambs; R had larger legs. Feed supplement increased average daily weight gain (ADG), slaughter live weight (SLW), hot carcass weight (HCW) and cold carcass weight (CCW), carcass yield, carcass length (CL), leg perimeter (LP), major thorax width (MTW), minor thorax width (MiTW), rib eye area and dorsal fat at 12th rib (DF12), and also decreased meat moisture. Organic chromium reduced dorsal fat at 12th rib and meat fat content.     

Effect of electrical stunning on meat quality of lamb

The effects of stunning on both initial and up to 2 weeks post mortem storage meat quality of Spanish Manchega breed lamb were studied. Twenty-four lambs were distributed into two groups. The first group (US; n =12) were slaughtered without previous stunning. In the second group (ES; n =12) animals were electrically stunned. Meat quality was assessed by examining pH, colour as L*, a*, b* values, water holding capacity (WHC) and shear force (SF). Stunning did not affect any parameter studied in the first 24 h post mortem. There were increasing differences between groups in pH (P<0.001) from 5 days onwards. In general stunning did not have an effect on WHC, SF and colour parameters. Ageing of meat affected SF in the ES group but not in the US one; however, there were no significant differences between treatments at any of the ageing times.     

Effect of dietary oregano oil supplementation on lamb meat characteristics

The effect of dietary oregano essential oil supplementation on lamb meat characteristics was investigated. Eight male and eight female Chios lambs were divided into two equal groups. The first group was fed with the control diet consisting of concentrated feed and alfalfa hay, whereas the second group consumed the same diet, the only difference being that the concentrated feed was uniformly sprayed with oregano essential oil (1 ml/kg). Duration of the experimental period was two months.

No differences were observed after oregano essential oil supplementation in final body weight (kg), body weight gain (g) and carcass yield (%). Tenderness of longissimus thoracis muscle, expressed as sarcomere length and shear force value, was not influenced by the treatment, whereas pH and colour parameters (yellowness–redness) appeared to increase (P < 0.05). Moreover, results showed that dietary incorporation of oregano essential oil exerted strong antioxidant effects retarding lipid oxidation (MDA formation) in meat during refrigerated and long-term frozen storage (P < 0.001).     

Effect of pre-slaughter management regarding transportation and time in lairage on certain stress parameters, carcass and meat quality characteristics in Kivircik lambs

Thirty Kivircik lambs were used to investigate effect of pre-slaughter treatment on certain haematological and biochemical parameters, carcass and meat quality characteristics. Lambs were divided into three treatments: 75 min transport and lairage for 18 h (TS-L18 h); 75 min transport and lairage for 30 min (TS-L30 min) and no pre-slaughter transport and lairage for 30 min (NTS). Treatment, as a main effect, did not influence haematological and biochemical parameters, but sampling time significantly affected these parameters, except total protein. Plasma cortisol concentration at exsanguination in TS-18 h, TS-30 min and NTS treatments were 117.34, 119.23 and 72.51 ng/ml, respectively. pH of longissimus dorsi muscle was higher in TS-L30 min than other treatments. TS-L30 min lambs had the highest shear force value, the lowest WHC and cooking loss. TS-L30 min treatment yielded the darkest meat immediately after cutting and 1 h later. Meat redness, yellowness and chroma values were similar in treatments.     

摄入有机硒与亚麻籽油对猪肉及其肉制品品质的影响

研究日粮添加有机硒和亚麻籽油对猪背长肌中硒含量、脂肪酸组成、肌原纤维蛋白特性及加工肉制品的影响。选取192头"杜×长×大"三元杂交猪,随机分为4组,设为C组(0.3 mg/kg亚硒酸钠+1.5%大豆油),S1组(0.3 mg/kg酵母硒+1.5%大豆油),S2组(0.5 mg/kg酵母+1.5%大豆油)及SL组(0.3 mg/kg酵母硒+1.5%亚麻籽油)。研究发现有机硒能显著提高猪背长肌中的硒贮存量(P0.05);亚麻籽油能改善肉品的n-6/n-3比例;亚麻籽油相比大豆油能显著提高肌原纤维蛋白的溶解性和凝胶强度(P0.05);0.5mg/kg有机硒在7~12d的储藏期内能减少香肠的脂质氧化(P0.05),但是香肠的微观结构和感官评价不受有机硒和亚麻籽油的影响。因此在日粮中添加亚麻籽油和有机硒有益于富硒富n-3PUFA猪肉的生产和加工。     

Sensory quality of meat from lambs fed garlic

The objective of this study was to determine whether the inclusion of garlic in a ration would have a negative impact on the flavour of lamb. The study used meat from 31 Merino wether lambs fed diets with varying levels of garlic (0%, 1.8% and 3.6%) for 10 weeks. Cooked samples of meat from the lambs were assessed for flavour and acceptability as lamb by an untrained consumer panel. There was no difference (P>0.05) between the treatments in flavour score, but the 3.6% garlic treatment group scored significantly higher in terms of acceptability as lamb (P<0.05) and was commented on positively by the panellists more frequently than the meat from any other treatment (P<0.05). These results suggest that the inclusion of garlic into the animals' feed did not have a negative impact on the flavour of the lamb and, at the high rate (3.6%), made the meat more acceptable to the panellists.     

Effects of the rearing season on carcass and meat quality of suckling Apennine light lambs

The aim of this study was to evaluate the effects of the rearing season (autumn vs winter) on the carcass and meat quality of light lambs, obtained according to the traditional farming system usual in central Italy. Eighty carcasses from 60 d ± 3 old unweaned Apennine single birth male lambs, permanently reared indoor, half in autumn (receiving milk from ewes permanently pastured) and half in winter (which dams did never acceded to pasture), were weighed, classified according to the EU classification system for light lambs, and their Longissimus lumborum meat was analysed for pH, colour, drip and cooking losses, proximate composition and fatty acids profile of intramuscular fat. Most of the carcasses fully responded to the 1st quality EU requirements and no effects of the rearing season was evident on carcass characteristics. On the contrary, L. lumborum of lambs born and reared in autumn, receiving milk from ewes permanently pastured, evidenced a lower Lightness L* (P = 0.02), a higher Chroma C* (P = 0.01), with a higher fat content (P = 0.04) than lambs reared in winter, which dams were permanently stall-fed. Moreover the intramuscular fat of the former was characterized by a greater PUFA concentration (P = 0.01), a more favourable n-6/n-3 ratio (P < 0.001), and a higher CLA content (P < 0.001) than the latter, as a result of the difference related to the sheep traditional feeding system.     

Carcass measurements and meat quality of Turkish Merino,Ramlic, Kivircik,Chios and Imroz lambs raised under an intensive production system

Effect of breed on carcass measurements and meat quality characteristics were investigated by using 46 lambs from Turkish Merino, Ramlic, Kivircik, Chios and Imroz breeds. Chios and Imroz carcasses had smaller values for carcass quality characteristics. Breed had no significant effect on pH at 45 min and 24 h post-mortem, water holding capacity and cooking loss. Kivircik and Imroz lambs had lower Warner Bratzler shear force values than those of Ramlic and Turkish Merino lambs (P < 0.01). Meat samples from Kivircik lambs had the highest redness value. Differences among breeds for sensory characteristics, except tenderness were not significant. Tenderness scores given to meat samples of Kivircik lambs were significantly higher (P < 0.01) than those of Turkish Merino, Ramlic and Imroz lambs. Indigenous Kivircik breed, which had high carcass quality as those of improved breeds, might be considered for production of better quality meat in Marmara Region of Turkey.     

Carcass and meat quality of Assaf milk fed lambs: Effect of rearing system and sex

The effect of sex and rearing system on growth and carcass and meat characteristics of milk fed Assaf lambs was studied. Thirty-six lambs, 18 males and 18 females were used. Twelve lambs remained with their mothers throughout the experiment (NR). Within 24–36 h of birth, the rest were housed individually and fed twice a day ad libitum (AAR) or at 70% of ad libitum consumption (RAR) with reconstituted cow’s milk. Sex did not affect animal performance, yet females showed higher carcass and non-carcass fat deposits. NR lambs showed greater BWG than AAR fed lambs, and AAR, higher than the RAR. Differences between naturally and artificially reared lambs in CCW and killing out percentage were not significant. Empty digestive tract and mesenteric fat weights were greater for RAR than NR lambs, with the AAR lambs demonstrating intermediate values; conversely, omental fat was greater in NR lambs. Carcass ether extract content was greater for NR lambs, possibly due to the greater growth. Use of ad libitum cow’s milk substitute in suckling lambs twice a day resulted in less body weight gain but similar killing out percentages compared to naturally raised lambs. A 70% restricted supply increased the days in suckling and reduced carcass fatness and compactness. Except for water loss, which was less in NR than artificially fed lambs, no differences were found in meat characteristics.     

Physico-chemical characteristics of carcass and meat Manchego-breed suckling lambs slaughtered at different weights

Forty-nine Manchego-breed lambs raised exclusively on their dams’ milk until slaughter were used in this study. The effects of gender and slaughter weight (10, 12 and 14 kg) on carcass fatness, meat quality and the fatty acid composition of their fat were studied. Fatness, and in particular dorsal-fat thickness (P0.01), increased with live weight. The effect of gender was even greater (P0.001), as female lambs presented the highest fatness values for all parameters studied. The smallest drop in m. longissimus pH values was seen in the lowest-weight (10 kg) lambs. These same lambs displayed the highest L* value and thus the lightest colour. Fatty acid composition, which was not influenced by live weight, was affected by gender. The subcutaneous fat of female lambs contained more linolenic acid (C18:3) (P0.01) and a greater proportion of polyunsaturated fatty acids than that of male lambs (P0.001). Likewise, the intramuscular fat of female lambs displayed a greater proportion of monounsaturated fatty acids (P0.001) than that of male lambs.     

Effect of the pre-slaughter logistic chain on meat quality of lambs

A total of 144 lambs were sampled in a 3 × 2 × 2 factorial design, testing three residence (stay) times at a pre-slaughter classification centre (0, 7, and 28 days) and two seasons (summer and winter), with two replicates in each season. Meat from the longissimus dorsi was analysed in terms of pH, WHC, texture, colour (L*a*b*, chroma and hue) and carcass bruising. Stay time had a significant effect (p < 0.001) on meat texture, while season had a significant effect (p < 0.001) on all variables analysed. Overall, stay time had less effect on meat quality than season and the interaction between treatments was not significant. Meat from lambs slaughtered in winter had some dark-cutting characteristics, with darker colour, higher ultimate pH, tougher meat and lower press juice. In conclusion, pre-slaughter classification and season are sources of stress for lambs and affect meat quality traits.     

Carcass and meat quality of light lambs using principal component analysis

Eighty-six male light lambs of Manchego breed were used in this study. Principal component (PC) analysis was performed to study the relationship between carcass quality variables (n=22) and between meat quality measures (n=21). The carcass quality was assessed using objective and subjective measurements of conformation and fatness besides the joints proportion and tissues proportion of the leg. The measurements used to evaluate meat quality were pH in longissimus dorsi and semitendinosus muscles, the colour, moisture, water holding capacity, cooking losses, texture and sensorial analysis on longissimus dorsi. The five first PCs explained about 77% of the total variability for carcass measures whereas for meat quality the 74% of the total variability was explained for the eight first PCs. All the carcass measurements showed similar weight to define the first PC, whereas the muscle and bone proportion as well as muscle:bone ratio of the leg were useful to define the second PC. The meat quality measures that were more effective to define the first PC were the meat colour measurements, whereas the sensorial variables defined the second PC. The projection of the carcass quality data in the first two PCs allowed to distinguish clearly between heavier carcasses (higher than 6.5 kg) and lighter carcasses (lower than 5.5 kg). The carcasses with a weight higher than 6.5 kg were on the left side of the figure, where the variables of conformation and fatness lie. The group of medium carcass weight were placed between the two previous groups. The projection of the meat quality data in the first two PCs did not differ between hot carcass weights, although there was a trend, the lighter carcasses lay on the left side of the graph, which implies small differences between meat quality in this range of carcass weight.     

Effects of tomato pomace supplementation on carcass characteristics and meat quality of fattening rabbits

The aim of this study was to determine how a feeding plan characterized by different levels of tomato pomace (TP) supplementation influences the carcass characteristics, the chemical, physical and sensorial characteristics of rabbit meat. 144 weaned crossbred rabbits were divided into three groups of 48 each. The first group was fed a basal diet without TP, while the other two groups were fed the basal diet after replacing part of the diet with TP at 3% and 6%, respectively. There was a significant difference between the experimental groups in terms of live and carcass weights. The meat of rabbits fed on a 6% TP diet exhibited higher yellowness (b*) and Chroma values when compared to others. The saturated fatty acid content in the longissimus dorsi muscle and perirenal fat decreased significantly with increasing TP inclusion, while polyunsaturated fatty acids increased. Furthermore, our results indicate that a diet integrated with 6% TP could influence positively the overall preference of cooked meat.