首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The major taste active component, glutamate (Glu), improves the taste of meat. In this study, we investigated the effect of a short‐term high‐protein (HCP) diet on the intramuscular free Glu content to improve the taste of meat. Furthermore, we elucidated how the muscle free Glu content was controlled by the HCP diet. Chicks (14 days old) were fed the control diet or HCP diet for 10 days. Plasma and muscle free amino acid concentrations, and activity and messenger RNA (mRNA) expression of muscle enzymes related to Glu metabolism were determined. Muscle free Glu content was increased (P < 0.01) by 51%. Activity and mRNA expression of glutaminase (GA), which is one of the major Glu‐related enzymes, were significantly decreased (P < 0.05) in the HCP group because of feedback inhibition. The mRNA expression of lysine α‐ketoglutarate reductase (LKR), which is the enzyme involved in lysine (Lys) degradation and Glu production, was significantly increased (P < 0.001) in the HCP group. These results suggest that short‐term dietary HCP feeding is an effective treatment for improving the taste of meat. Furthermore, our results suggest that the free Glu content in muscle is regulated by GA and LKR.  相似文献   

2.
Taste is a crucial factor of meat quality, and amino acids are important taste‐active components in meat. Here, the effects of dietary lysine (Lys) content on taste‐active components in meat, especially free glutamate (Glu), were investigated. Twenty‐eight‐day‐old broilers (Gallus gallus) were fed diets with graded Lys content of 90% or 100% of the recommended Lys requirement, (according to the National Research Council, 1994 ) for 10 days. Free amino acid content in meat and sensory scores of meat soup were estimated. Free Glu content, the main taste‐active component of meat, was significantly increased by a reduction of dietary Lys. Compared with the Lys 100% group (control), free Glu concentrations of meat were increased by 35.7% in the Lys 90% group (P < 0.05). In addition, free glycine, valine, isoleucine, leucine, histidine and threonine concentrations of meat were significantly increased in the Lys 90% group (P < 0.05). Sensory evaluation of meat soup made from the Lys 100% and 90% groups indicated different meat tastes. Sensory scores of taste intensity, umami and kokumi tastes were significantly higher in the Lys 90% group. These results suggest that a reduction of dietary lysine increased free glutamate content in meat and improved its taste.  相似文献   

3.
The aim of this study was to examine effects of dietary supplementation with Aspergillus awamori and feeding canola seed on the growth and fatty acid profile in broilers. Twenty‐eight chicks (15 days old) were assigned to the following groups: (1) control, fed a basal diet; (2) awamori, fed the basal diet supplemented with 0.05% A. awamori; (3) canola, fed a diet containing 5% canola seed; and (4) canola + awamori, fed the canola diet supplemented with A. awamori (seven birds/group). Body weight gain was increased by A. awamori but not influenced by canola seed. Breast muscle weight was increased in either awamori or canola groups. Although plasma triglyceride and cholesterol were decreased by feeding A. awamori or canola seed, fat content in the breast muscle were increased, accompanied by decrease in saturated fatty acids and increase in unsaturated fatty acids. Moreover, decreased thiobarbituric acid reactive substance and increased α‐tocopherol content in the breast muscle was observed in all experimental groups. In conclusion, these results suggested that feeding canola seed and A. awamori might improve growth performance, and modified muscle fatty acid profile and α‐tocopherol content, suggesting that they may improve meat quality.  相似文献   

4.
1. Regulation of meat taste is one effective method for improvement of meat quality. In this study, effects of dietary leucine (Leu) content on taste-active components, especially free glutamate (Glu), in meat were investigated. 2. Broiler chickens (28 d old) were fed on diets with graded dietary Leu content (100, 130 or 150% of Leu requirement in NRC, 1994) for 10 d before marketing. Taste-active components of meat (free amino acids and ATP metabolites) and sensory score of meat soup were estimated. 3. Free Glu content, the main taste-active component of meat, was significantly increased by dietary Leu. Compared with the Leu 130% group, free Glu was increased by 17% in the Leu 100% group. Free Glu of meat tended to decrease in the Leu 150% group. In contrast, inosine monophosphate content in meat did not change among all groups. 4. Sensory evaluation of meat soup from the Leu 100 and 150% groups showed that they had different meat tastes. Sensory scores of overall preference, umami taste and chicken-like taste were significantly higher in the Leu 100% group. 5. These results suggest that dietary Leu content is a regulating factor of free Glu in meat. Decreasing dietary Leu induces an increase in the free Glu content of meat and improves meat taste.  相似文献   

5.
The amino acid content of the liver, brain, serum and leg muscle of broiler breeder female chicks was not influenced appreciably at 4 and 8 weeks of age by feeding a diet containing sub‐optimum levels of lysine. The feeding of the low‐lysine diet produced a slight effect on the amino acid content of the breast muscle and a decided effect on the amino acid content of the skin and bone marrow at 4 and 8 weeks of age. The amino acid content of the heart tissue from chicks which received the 0.53% lysine diet was higher at 4 weeks of age. No explanation for this observation can be offered. The more decided changes were produced in the bone marrow of the chicks fed the low‐lysine diet at 4 and 8 weeks of age.

There is a possibility that feeding the low‐lysine diet had an effect on protein synthesis in the bone marrow. Chicks fed the low‐lysine diet had apparently overcome the lysine deficiency in the synthesis of protein of the bone marrow at the end of the 12th week.  相似文献   


6.
共轭亚油酸对肉仔鸡体组成和肉品品质的影响   总被引:1,自引:3,他引:1  
本试验旨在探讨日粮添加共轭亚油酸(CLA)对肉仔鸡体组成和肉品品质的影响。240只1日龄肉仔鸡随机分配到4个日粮处理组(0%、0.25%、0.5%和1%CLA),每个处理6个重复,每个重复10只鸡。试验结果表明:42d时,0.5%和1%CLA组肉仔鸡胸肌率显著高于对照组(P<0.05),1%CLA组肉仔鸡42d腿肌率显著高于对照组,肉仔鸡的腹脂率在各处理之间没有显著差异(P>0.05),1%CLA组肉仔鸡胸肌粗蛋白质粗脂肪比显著高于对照组(P<0.05)。0.5%、1%CLA组肉仔鸡胸肌滴水损失和丙二醛(MDA)含量显著降低(P<0.05)。试验结果表明,CLA可改善肉仔鸡屠体性状,增加鸡肉系水力和延长货架存放时间。  相似文献   

7.
Forty‐eight Duroc × Large White × Landrace pigs with an average initial body weight of 77.09 ± 1.37 kg were used to investigate the effects of combination of leucine (Leu) with arginine (Arg) or glutamic acid (Glu) on muscle growth, free amino acid profiles, expression levels of amino acid transporters and growth‐related genes in skeletal muscle. The animals were randomly assigned to one of the four treatment groups (12 pigs/group, castrated male:female = 1:1). The pigs in the control group were fed a basal diet (13% Crude Protein), and those in the experimental groups were fed the basal diet supplemented with 1.00% Leu (L group), 1.00% Leu + 1.00% Arg (LA group) or 1.00% Leu + 1.00% Glu (LG group). The experiment lasted for 60 days. Results showed an increase (p < 0.05) in biceps femoris (BF) muscle weight in the L group and LG group relative to the basal diet group. In longissimus dorsi (LD) muscle, Lys, taurine and total essential amino acid concentration increased in the LG group relative to the basal diet group (p < 0.05). In LG group, Glu and carnosine concentrations increased (p < 0.05) in the BF muscle, when compared to the basal diet group. The Leu and Lys concentrations of BF muscle were lower in the LA group than that in the L group (p < 0.05). A positive association was found between BF muscle weight and Leu concentration (p < 0.05). The LG group presented higher (p < 0.05) mRNA levels of ASCT2, LAT1, PAT2, SANT2 and TAT1 in LD muscle than those in the basal diet group. The mRNA levels of PAT2 and MyoD in BF muscle were upregulated (p < 0.05) in the LG group, compared with those in the basal diet group. In conclusion, Leu alone or in combination with Glu is benefit for biceps femoris muscle growth in fattening pig.  相似文献   

8.
1. The effects of dietary branched-chain amino acids (BCAAs) including leucine (Leu), isoleucine (Ile) and valine (Val) on taste-active components, especially free glutamate (Glu), in meat were investigated. 2. Broiler chickens (28 d old) were given varied dietary BCAA levels for 10 d before marketing. Dietary BCAA content ratios were either 100:100:100 (Low Leu group), 150:100:100 (Control group) or 150:150:150 (High Ile + Val group) for Leu:Ile:Val (% of each BCAA requirement according to NRC, 1994). Taste-related components of meat (free amino acids and ATP metabolites) and sensory scores of meat soup were estimated. 3. Free Glu content, the main taste-active component of meat, was significantly increased by dietary BCAA. Compared to the Control group, free Glu content increased by 30% in the High Ile + Val group. However, the inosine monophosphate (IMP) content in meat did not change among groups. 4. Sensory evaluation of meat soups showed that Control and High Ile + Val groups had different meat flavours. The sensory score of overall taste intensity was significantly higher in the High Ile + Val group. 5. These results suggest that dietary BCAA concentrations regulate free Glu in meat. Increasing dietary Ile + Val induces an increase in free Glu content of meat, improves meat taste and is more effective for increasing free Glu content in meat than decreasing dietary Leu level.  相似文献   

9.
An experiment was undertaken to determine if dietary conjugated linoleic acid (CLA) influences the early stage of the inflammatory response caused by a single injection of Salmonella enteritidisi lipopolysaccharide (LPS) in male broiler chicks. Chicks (7 days old) were fed either 0 or 10 g CLA/kg in their diet for 21 days. At 28 days old, birds were injected intraperitoneally with 1.5 mg LPS/kg body weight after 12 h fasting. Changes in feed intake, rectal temperature and plasma α‐1 acid glycoprotein and ceruloplasmin concentrations were measured during 24 h after LPS injection. Chicks fed the CLA diet were fed more feed for 24 h, had a lower rectal temperature at 9 and 24 h and a lower plasma α‐1 acid glycoprotein concentration at 24 h after LPS injection than chicks fed the basal diet. Plasma ceruloplasmin concentration tended to be lower in chicks fed the CLA diet than in chicks fed the basal diet. The results suggest that dietary CLA alleviate undesirable early inflammatory response due to LPS injection in male broiler chicks.  相似文献   

10.
We investigated the effects of a low crude protein (CP) diet and a low CP diet supplemented with synthetic essential amino acids (EAA) on the meat quality of broiler chickens. Twenty‐one‐day‐old chickens were assigned to one of three diets: control, low CP (LCP), or low CP supplemented with EAA (ELCP). The chickens received these diets for 10 days. The shear force value (SFV) and free glutamate content of the Pectoralis major muscle were measured as indicators of the meat toughness and taste. The collagen and crude fat content of the muscle and the cross‐sectional area of myofibers were measured to evaluate the effects of the LCP and ELCP diets on meat toughness. The SFV of the ELCP group was 47% lower than that of the control group (P < 0.01). However, the LCP diet did not affect the SFV. The collagen and crude fat content were not affected by the dietary treatment. The cross‐sectional area was lower in the LCP and ELCP groups (P < 0.05) than the control group. The free glutamate content of muscle was not affected by the dietary treatment. Thus, a low CP diet supplemented with EAA is an effective means of producing tender meat.  相似文献   

11.
The experiment was carried out to determine the effects of liquid DL‐methionine hydroxy analog‐free acid (LMA) and dry DL‐methionine (DLM) on growth performance, carcass quality and chemical composition of the livers of broiler chicks during 0–6 weeks of age. Four hundred and fifty male commercial broiler chicks (Ross strain) were used. The chicks were divided into three groups, and each group consisted of six replicates of 25 chicks each. The chicks were kept in floor pens, and water and feed were supplied ad libitum throughout the experiment. Three experimental diets were provided as follows: (i) corn–soybean‐based diet deficient in methionine; (ii) methionine‐deficient corn–soybean‐based diet supplemented with DLM to meet the methionine requirements of broiler chicks; and (iii) methionine‐deficient corn–soybean‐based diet supplemented with LMA (1.25‐fold (w/w) the amount of DLM supplied to the second group, given an assumption that 100 units of liquid LMA can be replaced by 80 units DLM to give similar performance results). During the starter period, the weight gains of chicks fed LMA or DLM were significantly greater than those in chicks receiving the methionine‐deficient diet (P < 0.05), and the addition of LMA significantly improved weight gain compared with the addition of DLM. Adding DLM or LMA significantly improved the feed conversion ratio (FCR) and percentage of uniformity (P < 0.05). No significant differences between the effects of DLM and LMA on these parameters were found. During the grower period (3–6 weeks of age), weight gain, FCR, uniformity and feed intake of chicks that received diet supplemented with DLM or LMA were superior to those of the methionine‐deficient group (P < 0.05). Chicks fed LMA had the same bodyweight gain and uniformity as those fed DLM. However, adding LMA resulted in a significant increase of FCR resulting from excess feed consumption. Outer breast meat yields were significantly improved and abdominal fat was significantly decreased when methionine sources were added (P < 0.05), and adding LMA tended to promote edible meat growth better than did adding DLM. Although no significant effects of methionine sources on the chemical composition of the liver were seen, adding methionine sources tended to increase liver fat content. In conclusion, it seems that the bioefficacy of LMA relative to DLM is not less than 80%. Therefore, chicks fed with diet supplemented with 1.25‐fold (w/w) as much LMA as DLM might exceed requirements for growth performance, while meeting requirements for meat production. Moreover, the relative bioefficacies of LMA and DLM between the starter and grower periods may perhaps be different.  相似文献   

12.
Excessive lipid peroxidation negatively affects the physiological response and meat quality of chickens. Delaying post‐hatch feeding was previously found to increase lipid peroxidation in the skeletal muscle of finishing broiler chickens. The aims of this study were to investigate the effects of delayed post‐hatch feeding on lipid peroxidation and the mRNA expressions of antioxidant enzymes in the pectoralis major muscle of broiler chicks during the post‐hatching period. Newly hatched chicks either had immediate free access to feed (freely‐fed chicks) or had no access to feed from 0 to 2 days old (delayed‐fed chicks), after which both groups were fed ad libitum until 4 or 13 days old. The lipid peroxidation level was higher in the delayed‐fed than freely‐fed chicks at 2, 4, and 13 days old. At 2 days old, the mRNA expressions of Cu/Zn‐SOD, Mn‐SOD, and GPX7 were lower in the delayed‐fed than freely‐fed chicks, while catalase mRNA levels did not differ. Furthermore, at 4 and 13 days old, lower mRNA expressions of Cu/Zn‐SOD and Mn‐SOD were observed in the delayed‐fed than freely‐fed chicks. These results suggest that delaying post‐hatch feeding reduces the mRNA levels of Cu/Zn‐SOD and Mn‐SOD, consequently affecting muscle lipid peroxidation in chicks during subsequent growth.  相似文献   

13.
This experiment was conducted to determine the optimal standardized ileal digestible lysine (SID Lys) level in diets fed to primiparous sows during lactation. A total of 150 (Landrace × Large White) crossbred gilts (weighing 211.1 ± 3.5 kg with a litter size of 11.1 ± 0.2) were fed lactation diets (3325 kcal metabolizable energy (ME)/kg) containing SID Lys levels of 0.76, 0.84, 0.94, 1.04 or 1.14%, through 28 days lactation. Gilts were allocated to treatments based on their body weight and backfat thickness 48 h after farrowing. Gilt body weight loss was significantly (P < 0.05) decreased by increasing dietary SID Lys levels. Fitted broken‐line (P < 0.05) and quadratic plot (P < 0.05) analysis of body weight loss indicated that the optimal SID Lys for primiparous sows was 0.85 and 1.01%, respectively. Average daily feed intake (ADFI), weaning‐to‐estrus interval and subsequent conception rate were not affected by dietary SID Lys levels. Increasing dietary lysine had no effect on litter performances. Protein content in milk was increased by dietary SID Lys (P < 0.05). Dietary SID Lys tended to increase concentrations of serum insulin‐like growth factor I (P = 0.066). These results of this experiment indicate that the optimal dietary SID Lys for lactating gilts was at least 0.85%, which approaches the recommendation of 0.84% that is estimated by the National Research Council (2012).  相似文献   

14.
The present study investigated the influence of a diet largely comprising rice whole‐crop silage (rWCS) on growth performance, carcass and meat characteristics, and expression of genes involved in muscle growth of Japanese Black steers. Steers were randomly separated into rWCS‐fed (rWCS ad libitum and restricted feeding of concentrate) and concentrate‐fed groups. Total digestible nutrient intake and daily gain (DG) decreased in rWCS‐fed steers in comparison with concentrate‐fed steers, whereas dressed carcass weight and final body weight did not significantly differ between the groups. Decreases in drip loss in the muscle of rWCS‐fed steers may be caused by α‐tocopherol and β‐carotene in muscle. Feeding large amounts of rWCS to steers may maintain quantitative productivity of beef steers equally to a concentrate‐based diet, and improve the qualitative productivity. Results of gene expression suggest that activation of skeletal muscle growth in rWCS‐fed steers may occur at the late fattening period owing to a decrease in myostatin and increase in myosin heavy chain gene expression. Preadipocyte factor‐1 and myostatin genes may be strongly involved in the control of lipid accumulation. This rearing system would allow beef production to switch to rWCS‐based diets from concentrate‐based diets.  相似文献   

15.
It has been previously established that growth and carcass qualities of chicks are modified by genotype and dietary amino acid supply. In this study, we evaluated the effects of lysine deficiency and genetic selection on muscle protein metabolism. Chicks originating from an experimental line selected for breast development (QL) and its control line (CL) were provided ad libitum access to isoenergetic diets containing 20% crude protein but differing in their lysine content (0.75 or 1.01%). Protein fractional synthesis rates (FSR) were measured in vivo in the pectoralis major and sartorius muscles of 3-wk-old chickens (flooding dose of [3H]phenylalanine). Fractional breakdown rates (FBR) were estimated as the difference between synthesis and deposition. Lysine deficiency reduced (P < 0.001) growth performance and muscle weights and increased (P < 0.05) muscle FSR, capacity for protein synthesis (muscle RNA:Protein, Cs) and FBR. Although QL birds grew faster and had heavier pectoralis major muscles than CL birds (P < 0.05), there was no line difference in sartorius weight (P = 0.15). No difference between the lines was observed in sartorius protein metabolism (P > 0.14). In the pectoralis major muscle, chicks of both lines receiving an adequate lysine intake also exhibited similar protein turnover rates. However, in chicks fed the lysine-deficient (0.75% lysine) diet, FSR and Cs were higher in QL than in CL chicks (P < 0.05), and FBR tended (P = 0.07) to be higher in QL chicks. This increased protein turnover in the QL birds on the lysine-deficient diet suggests that the responsiveness of muscle protein metabolism to amino acid supply is modified by genetic selection for breast development.  相似文献   

16.
The current study examines the effect of different finishing diets (hay‐ vs. maize‐silage on meal ration) on carcass quality, physical, chemical and sensory properties, and fatty acid profiles of buffalo meat. Twenty male Italian Mediterranean buffaloes (246 ± 9.00 kg live weight) were distributed at random into two groups at the beginning of the finishing period (368 ± 20 days). The buffaloes were offered two finishing diets: a maize silage (MS) or an alfalfa hay (AH) diet. No significant differences were found between dietary treatments for live and carcass weight. Meat chemical composition was influenced by dietary treatment. A higher fat content was detected in meat from animals finished with MS than AH (P < 0.05). Overall, the data indicated differences between the fatty acid profiles of meat as a consequence of different feeding systems. The higher fat deposition in the MS group resulted in meat with a less favorable fatty acid profile (i.e. a lower polyunsaturated/saturated fatty acid ratio and α‐linolenic fatty acid content) in relation to human health compared with meat from animals fed the AH diet.  相似文献   

17.
This study was carried out to evaluate the nutritional effects of rice feeding and carnitine addition to a diet for broiler chicks. Thirty‐six male 10‐day‐old broiler chicks were assigned to one of the following four treatment groups: corn‐based diet (corn group), rice‐based diet (rice group), and each diet with added carnitine (100 ppm). The experimental period was 2 weeks. Rice feeding resulted in significantly higher growth performance (body weight gain and feed efficiency) compared to corn feeding. Carnitine addition also resulted in higher growth performance. Breast muscle and thigh muscle weight (g) were significantly higher in broiler chicks fed rice and those fed diets with added carnitine. Liver mRNA expression of IGF‐I was significantly higher in broiler chicks fed rice compared to those fed corn. There was no significant difference in mRNA expression of muscle atrogin‐1 or liver CPT‐I between broiler chicks fed rice and those fed corn, not between broilers chicks fed diets containing carnitine or not. Overall, these results show that rice feeding and carnitine addition improve the growth performance of broiler chicks by increasing mRNA expression of liver IGF‐I. In addition, carnitine action is not affected by different cereals (corn and rice).  相似文献   

18.
Lysine (Lys) is the first limiting amino acid (AA) in most feed formulations for pigs and most abundant, along with leucine, in muscle proteins. An experiment was conducted with 17 pigs (17.7 ± 0.05 kg initial BW) to identify a role of dietary Lys in the control of protein synthesis in pigs. Fourteen pigs were randomly assigned to one of the two wheat‐based dietary treatments: Lys‐deficient, 3.0 g/kg (DEF) and Lys‐adequate, 10.8 g/kg (ADE). Samples from jejunum mucosa, liver, Longissumus and Semitendinosus muscles, and blood were collected. The other three pigs were sacrificed at the beginning of the trial to measure basal carcass composition. Weight gain, gain:feed ratio, Lys intake and loin eye area were greater in ADE than in DEF pigs (p < 0.01). Muscle‐related carcass characteristics were better, and myosin heavy chain IIb expression (MyHC IIb) in Semitendinosus was higher in ADE than in DEF pigs. Expression of AA transporters CAT‐1 was lower (p < 0.05), serum Lys was higher and serum Val was lower in pigs fed the ADE diet. The higher muscularity, MyHC IIb expression in Semitendinosus muscle and Lys serum of pigs fed the ADE diet suggest that Lys increases growth rate not only by functioning as protein construction unit but also as potential control of the protein synthesis process.  相似文献   

19.
本试验旨在研究低蛋白质饲粮补充过瘤胃赖氨酸(RPLys)和过瘤胃蛋氨酸(RPMet)对荷斯坦公牛生长性能、屠宰性能、肉品质及氮代谢的影响.选取36头健康无疾病的荷斯坦公牛,随机分为3组,每组12头牛.对照组(Ⅰ组)饲喂蛋白质水平为13%的正常饲粮,2个试验组(Ⅱ、Ⅲ组)均饲喂蛋白质水平为11%的低蛋白质饲粮,同时Ⅱ组补...  相似文献   

20.
The present experiment tested a dietary supplementation with linseed oil and selenium to growing rabbits. The basal diet (B) contained 3% sunflower oil, while it was substituted with 3% linseed oil in the experimental feed (S). The selenium (Se) content of the two diets was 0.10 vs. 0.46 mg/kg. Rabbits were fed with B diet from the age of 18 days. One group was fed with the B diet until 11 weeks of age (group B), whereas the experimental groups were fed with S diet for 1, 2, 3 or 4 weeks (groups S1, S2, S3 and S4, respectively), before slaughtering (11 weeks of age). Live performance and carcass traits of rabbits, fatty acid (FA) profile and selenium content of their hind leg (HL) and Longissimus thoracis et lumborum (LTL) meat were considered in this study. In addition, the effect of two different cooking methods on the nutritional value of the enriched HL meat was also assessed. The tested dietary supplementation only minimally affected the live performance and carcass traits of rabbits. The S supplementation significantly reduced the Σ n‐6 FA and increased the Σ n‐3 FA of the HL meat and LTL meat, compared to the B diet (p < 0.001); thus, n‐6/n‐3 ratio was improved (p < 0.001). In addition, HL meat and LTL meat of S fed rabbits were significantly enriched in Se reaching a twofold increase in both meat cuts (p < 0.01). Therefore, the S supplementation improved the functional value of the rabbit meat. The heat treatment affected cooking loss, Se and vitamin E contents as well as the oxidative status of the HL meat (p < 0.001), with the different cooking methods providing different results. In addition, even if the beneficial C20:5 n‐3 and C22:6 n‐3 decreased with cooking, the n‐6/n‐3 ratio remained unaffected.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号