不同蛋白水平饲粮对4～8周龄麒麟母鸡屠宰性能和肌肉品质的影响

研究通过对4～8周龄麒麟鸡屠宰性能和肌肉品质的测定,确定鸡的适宜蛋白质水平。选取4周龄麒麟母鸡200只,按体重相近原则随机分为5组,每组4个重复,每个重复10只鸡,分别饲喂不同蛋白水平的饲粮(15%、17%、19%、21%、23%),试验期28 d。结果显示,饲粮中能量水平为12.40 MJ/kg时,随着蛋白水平的提高,4～8周龄麒麟母鸡的屠宰性能有所改善,19%和21%蛋白质水平麒麟鸡屠宰率、全净膛率、半净膛率最高,胸肌滴水损失率最低,胸肌和腿肌蛋白质含量较高。以屠宰性能和肌肉品质作为评价指标,4～8周龄麒麟母鸡适宜的饲粮粗蛋白质水平为19%～21%。     

蜂胶残渣对28~56日龄黄羽肉鸡生长性能、屠宰性能及肌肉品质的影响

本试验旨在研究蜂胶残渣对28~56日龄黄羽肉鸡生长性能、屠宰性能及肌肉品质的影响,进而为蜂胶残渣的开发和利用提供依据。选取28日龄闽南黄羽肉鸡540只,随机分为3组,每组6个重复,每个重复30只。Ⅰ组饲喂基础饲粮,Ⅱ组、Ⅲ组分别在基础饲粮中添加0.5%和1.0%的蜂胶残渣,试验期28 d。结果表明:1)蜂胶残渣对肉鸡平均日增重和料重比没有显著影响(P0.05)。2)蜂胶残渣对屠宰率、半净膛率没有显著影响(P0.05),但能显著提高全净膛率(P0.05);Ⅲ组腿肌率和胸肌率显著高于Ⅰ组(P0.05)。3)肉色方面,蜂胶残渣对腿肌和胸肌的亮度(L*)和黄度(b*)值没有显著影响(P0.05),但显著降低了Ⅲ组胸肌和腿肌的红度(a*)值(P0.05)。肉质方面,与Ⅰ组相比,Ⅱ组、Ⅲ组腿肌剪切力显著降低(P0.05),胸肌失水率显著降低(P0.05);Ⅱ组、Ⅲ组胸肌的滴水损失显著低于Ⅰ组(P0.05),Ⅲ组腿肌滴水损失也显著低于Ⅰ组(P0.05)。由此可见,饲粮中添加1.0%蜂胶残渣能改善黄羽肉鸡的屠宰性能和鸡肉品质。     

饲粮蚕沙水平对扬州鹅仔鹅生长性能、肌肉品质、营养成分和风味物质含量的影响

本试验旨在通过研究饲粮蚕沙水平对扬州鹅仔鹅生长性能、肌肉品质、营养成分以及硫胺素、肌苷酸、氨基酸等风味物质含量的影响,探讨仔鹅饲粮中蚕沙的适宜添加水平。选取330只11日龄健康、体重相近的扬州鹅公鹅,随机分5个组,每组6个重复,每个重复11只。对照组(Ⅰ组)饲喂基础饲粮,试验组(Ⅱ、Ⅲ、Ⅳ、Ⅴ组)分别饲喂添加3%、6%、9%、12%蚕沙的试验饲粮。试验期从仔鹅11日龄至70日龄。结果表明:1)与对照组相比,Ⅳ组和Ⅴ组显著降低了仔鹅体重和平均日增重(P0.05),显著提高了料重比(P0.05)。2)饲粮中添加蚕沙显著降低了仔鹅胸肌肉色和腿肌剪切力(P0.05),且均呈一次线性关系(P0.05)。3)饲粮添加蚕沙显著提高了仔鹅胸肌、腿肌水分的含量(P0.05),显著降低了仔鹅胸肌、腿肌粗蛋白质、粗脂肪的含量(P0.05)。Ⅳ组腿肌粗蛋白质、粗脂肪含量显著低于对照组(P0.05);Ⅴ组胸肌和腿肌的粗蛋白质、粗脂肪含量显著低于对照组(P0.05),水分含量显著高于对照组(P0.05)。4)饲粮添加蚕沙显著提高了仔鹅胸肌、腿肌硫胺素含量(P0.05),对胸肌、腿肌中肌苷酸和氨基酸含量无显著影响(P0.05)。由此可知,饲粮添加适量蚕沙对仔鹅生长性能、肌肉品质、常规养分含量以及肌苷酸、氨基酸等风味物质含量没有不良影响,并具有改善肌肉嫩度,提高硫胺素含量的作用。在生产实践中仔鹅饲粮中蚕沙的添加水平不宜超过6%。     

冷藏时间对麒麟鸡肌肉品质、营养指标及肌苷酸含量的影响

为了研究冷藏时间对不同生长阶段屠宰的麒麟鸡肌肉的影响，并为合理选择冷藏时间提供理论依据，试验选取4周龄和8周龄的健康麒麟母鸡各100只进行屠宰，测定不同冷藏时间胸肌和腿肌肉质指标、营养指标及肌苷酸(inosinic acid, IMP)含量。结果表明：在4℃条件下保存的肌肉，与冷藏45分钟比较，冷藏4小时时胸肌和腿肌pH值均降低，12小时较4小时均上升，12～24 h内pH值差异不显著(P>0.05)且pH值相对稳定。胸肌和腿肌的滴水损失分别在冷藏0～72 h和0～60 h内呈现不断上升的趋势，12～36 h内各冷藏时间点的滴水损失差异不显著(P>0.05)且相对稳定，60,72小时滴水损失显著高于0,12小时(P<0.05)。4周龄麒麟鸡胸肌的剪切力呈现先降低后升高再降低的趋势，在冷藏36小时时达到最低值；腿肌的剪切力在冷藏24小时时达到最低值，36小时后的变化规律和胸肌一致；8周龄麒麟鸡胸肌和腿肌的剪切力变化规律不明显，分别在24,36小时及12,24,48小时较低。4周龄屠宰后，随着冷藏时间的延长，胸肌和腿肌a^*值逐渐升高，72小时显著高于...     

1～28日龄麒麟鸡钙需要量

本试验旨在研究不同饲粮钙水平对麒麟鸡生长性能、屠宰性能、肉品质、趾骨特性及血清生化指标的影响,以确定麒麟鸡饲粮中钙的适宜水平。选用1日龄麒麟鸡240只,随机分为5个组,每组6个重复,每个重复8只鸡。各组分别饲喂钙水平为0.75%、0.90%、1.05%、1.20%和1.35%(可利用磷水平为0.45%,维生素D3水平为1 250 IU/kg)的玉米-豆粕型试验饲粮,试验期28 d。结果表明:1)饲粮钙水平对麒麟鸡平均日增重、平均日采食量、腿病发生率和死亡率有显著影响(P0.05),但对料重比影响不显著(P0.05),随着饲粮钙水平的提高,平均日增重和平均日采食量呈断线变化(P0.05)。2)饲粮钙水平对麒麟鸡屠宰率、半净膛率、全净膛率、胸肌率、腿肌率以及胸肌的p H、肉色和滴水损失率没有显著影响(P0.05),但腹脂率随着饲粮钙水平的增加有先升高后降低的变化趋势(P=0.083)。饲粮钙水平对胸肌的剪切力有显著影响(P0.05),且随钙水平的提高呈二次曲线变化(P0.05)。3)饲粮钙水平对麒麟鸡趾骨脱脂干重及趾骨粗灰分、粗灰分钙含量有显著影响(P0.05),且趾骨粗灰分和粗灰分钙含量随着饲粮钙水平的提高呈二次曲线和断线变化(P0.05)。4)饲粮钙水平对血清碱性磷酸酶活性影响不显著(P0.05),但显著影响麒麟鸡血清钙、磷含量(P0.05),随着饲粮钙水平的提高,血清磷含量呈断线变化(P0.05)。综上所述,平均日增重、平均日采食量、胸肌剪切力、趾骨粗灰分和粗灰分钙含量、血清磷含量可敏感反映麒麟鸡体内钙的营养状况,综合以上敏感指标得出1~28日龄麒麟鸡饲粮中钙需要量为1.20%。     

茶多酚对0～18周龄狮头鹅生长性能、屠宰性能及肌肉品质的影响

本试验旨在探究饲粮中添加茶多酚对0～18周龄狮头鹅生长性能、屠宰性能、肌肉品质及抗氧化能力的影响。试验采用单因素完全随机试验设计,选取1日龄体重相近的健康雄性狮头鹅360只,随机分为3组,每组6个重复,每个重复20只鹅。对照组饲喂基础饲粮,试验Ⅰ和Ⅱ组分别在基础饲粮中添加500和1 000 mg/kg茶多酚,试验期18周。结果表明：1）与对照组相比,各试验组13～18周龄料重比均显著降低（P<0.05）。2）与对照组相比,各试验组腹脂率均显著降低（P<0.05）。3）与对照组相比,各试验组胸肌24 h红度（a*）值、腿肌45 min a*值均显著提高（P<0.05）,胸肌剪切力显著降低（P<0.05）;试验Ⅱ组腿肌pH45 min和pH24 h显著提高（P<0.05）,腿肌24 h亮度（L*）值和胸肌滴水损失显著降低（P<0.05）。4）与对照组相比,各试验组胸肌和腿肌粗灰分含量均显著降低（P<0.05）,试验Ⅱ组胸肌水分含量显著降低（P<0.05）。5）与对照组相比,各试验组胸肌和腿肌中总超氧化物歧化酶（T-SOD）活性均显著提高（P&...     

超微粉碎凹凸棒石对肉鸡肌肉品质的影响

本试验旨在研究超微粉碎凹凸棒石对肉鸡肌肉品质的影响。选取1日龄爱拔益加肉鸡192只,随机分成3组,每组8个重复,每个重复8只。对照组饲喂基础饲粮,2个试验组分别饲喂在基础饲粮中添加1%常规粉碎凹凸棒石、1%超微粉碎凹凸棒石的试验饲粮,试验期为42 d。结果表明:与对照组相比,饲粮中添加常规粉碎凹凸棒石或超微粉碎凹凸棒石对肉鸡肌肉常量化学成分均无显著影响(P0.05);饲粮中添加超微粉碎凹凸棒石显著降低了腿肌中铬和镉的含量(P0.05),显著提高了胸肌中铁的含量(P0.05),并显著降低了胸肌和腿肌红度值以及胸肌黄度值(P0.05);饲粮中添加常规粉碎凹凸棒石则仅显著降低了腿肌中铬的含量和胸肌红度值(P0.05)。与对照组和常规粉碎凹凸棒石组相比,超微粉碎凹凸棒石组胸肌谷胱甘肽过氧化物酶活性显著提高(P0.05)。由此得出,饲粮中添加超微粉碎凹凸棒石能减少肌肉中有毒重金属残留,影响肌肉色度,提高胸肌的抗氧化能力,且效果优于常规粉碎凹凸棒石。     

蚯蚓粉对寿光鸡生产性能和肉品质的影响

试验将600只1日龄同批孵化、体重相近、健康的寿光鸡随机分成两组,每组三个重复,每个重复100只鸡(公母各半)。对照组饲喂基础饲粮,试验组在基础饲粮中添加5%的蚯蚓粉,试验期为90 d。测定试验期间寿光鸡的生产性能指标,试验结束时每组分别随机抽取20只鸡屠宰取胸肌、腿肌作屠宰试验。结果表明:(1)试验结束时试验组鸡体重和平均日增重极显著高于对照组(P0.05);平均日耗料量、料肉比降低,差异极显著(P0.01)。(2)试验组屠宰率和半净膛率极显著高于对照组(P0.01);腹脂率极显著降低(P0.01)。(3)试验组胸肉品质(p H、系水力、失水率、滴水损失、肌苷酸)较对照组差异极显著(P0.01);腿肌肉剪切力、系水力、滴水损失、失水率和肌苷酸差异极显著(P0.01)。胸肌肉中营养物质(水分、粗蛋白质、粗脂肪、钙、磷、铜、锌)试验组较对照组差异极显著(P0.01);腿肌肉中营养物质(水、粗蛋白质、脂肪、钙、磷、铁、锌)含量与对照组差异极显著(P0.01)。(4)品尝评定中,试验组胸肌肉和腿肌肉的总体评分均极显著高于对照组(P0.01),即试验组鸡肉的风味好于对照组。由此可知,日粮中添加5%蚯蚓粉可以显著提高寿光鸡生产性能、屠宰性能以及鸡肉的品质和风味等。     

饲粮添加壳寡糖和干酪乳杆菌对肉鸡生长性能、肌肉品质及抗氧化性能的影响

本试验旨在研究饲粮中添加壳寡糖与干酪乳杆菌对肉鸡生长性能、肌肉品质及抗氧化性能的影响。选用1日龄爱拔益加(AA)健康肉公鸡240只,随机分为4组,每组6个重复,每个重复10只。对照组饲喂基础饲粮,试验组分别在基础饲粮中添加120 mg/kg壳寡糖、2×106CFU/g干酪乳杆菌、120 mg/kg壳寡糖+2×106CFU/g干酪乳杆菌。试验期为42 d。结果表明:1)与对照组相比,单独添加壳寡糖或壳寡糖与干酪乳杆菌共同添加可显著提高肉鸡平均日增重、胸肌和腿肌红度(a*)值,肌肉脂肪和肌苷酸含量以及胸肌单不饱和脂肪酸和多不饱和脂肪酸含量(P0.05),显著降低胸肌饱和脂肪酸含量、腿肌黄度(b*)值(P0.05)。2)饲粮中单独添加干酪乳杆菌显著提高腿肌脂肪及胸肌单不饱和脂肪酸含量(P0.05),显著降低胸肌饱和脂肪酸含量(P0.05)。3)饲粮中单独添加壳寡糖、干酪乳杆菌或二者共同添加均可显著降低血浆、胸肌和腿肌丙二醛含量(P0.05),显著提高血浆、胸肌和腿肌总超氧化物歧化酶活性及总抗氧化能力(P0.05),显著降低血浆肌酸激酶的活性(P0.05)。综合分析表明,饲粮中添加壳寡糖、干酪乳杆菌或二者共同添加可提高肉鸡的生长性能和抗氧化性能,改善肌肉品质,而单独添加120 mg/kg壳寡糖效果最佳。     

五味子提取物对低脂系肉仔鸡肉质的影响

本试验采用单因子试验设计,将144羽1日龄健康、体重均一的低脂系肉仔鸡随机分为两组,每组6个重复,每个重复12羽。对照组饲喂基础日粮,试验组饲喂添加0.125%五味子提取物组的基础日粮,试验期为8周,研究五味子提取物对低脂系肉仔鸡肉质的影响。结果表明:(1)与对照组相比,五味子提取物组肉仔鸡胸肌纤维密度显著提高,腿肌直径显著降低(P0.05),腿肌纤维密度有升高趋势,胸肌直径有降低趋势;(2)与对照组相比,五味子提取物组胸肌和腿肌的水分、蛋白质与脂肪含量无显著差异(P0.05);(3)五味子提取物显著降低了肉仔鸡胸肌和腿肌剪切力(P0.05),胸肌和腿肌pH、红度(a*)、黄度(b*)有升高趋势(P0.05),滴水损失和蒸煮损失有降低趋势(P0.05)。     

Distribution of muscle fiber type in fetal equine gluteus medius muscle

The gluteus medius muscles were removed from a four-year-old female Welsh pony and her nine-month-old fetus. The muscles were divided into sections which were histochemically examined to determine the variation in the distribution of fast-twitch-glycolytic (FG), fast-twitch oxidative glycolytic (FOG), and slow-twitch oxidative (SO) muscle fibers throughout the entire cross-section of the muscle. The fetal muscle had a larger percent of FOG fibers and smaller percent of SO fibers than the same muscle from the mare. Variation in the distribution of muscle fiber type within the fetal gluteus medius was found. This is the first study of fiber type variation in fetal equine muscle.     

大白猪不同部位肌肉肌纤维表达特点

取3头本地大白猪4个不同部位的肌肉组织,运用免疫组化方法,测定快肌纤维和慢肌纤维的表达情况。免疫组化结果表明在猪的不同部位肌肉组织中,快肌纤维与慢肌纤维含量之间存在极显著差异(P<0.01)。快肌纤维的表达在股二头肌中最多,其次为背最长肌和内脊肌,头半棘肌最少。慢肌纤维的表达在头半棘肌中最多,其次为内脊肌和股二头肌,在背最长肌中表达最少。通过对猪4种骨骼肌中快肌纤维和慢肌纤维的免疫组化分析显示,二者的表达在猪不同部位的肌肉存在显著差异。     

Regionalisation of the muscle fascicle architecture in the equine longissimus dorsi muscle

REASON FOR PERFORMING STUDY: The longissimus dorsi is the largest muscle in the equine back and plays an important role in locomotor ability and performance in the horse. In vivo studies suggest that the mechanical function varies between different muscle segments, in part determined by anatomy. It is possible therefore that variations in function reflect variations in the anatomy of the longissimus dorsi along its length. OBJECTIVES: To identify if there are regional variations in muscle architecture of the longissimus dorsi. METHODS: Computed tomography scans were obtained from 8 cadaver backs to identify the cross-sectional area and volume of the muscle. The 3D orientations of the muscle fascicles were quantified in situ by their direction cosines using a magnetic digitisation system. RESULTS: Mean +/- s.e. volume of the muscle was 2.34 +/- 0.18 l for each side and mean length of the vertebral column from T4 to L6 dorsal spinous processes was 56.57 +/- 2.0 cm. There were significant differences in the cross-sectional area and the moment arm lengths between muscle segments (P<0.05). In the lumbar region, the mediolateral moment arms were 2-3 times greater than the dorsoventral moment arms. There were significant variations in the direction cosines (n = 7129) between muscle segments and between different regions within each segment (P<0.05). POTENTIAL RELEVANCE: These observations indicate that the muscle fascicle architecture predisposes the longissimus dorsi to different functions both along its length and between different regions within each segment. Detailed 3D anatomical measures of the structure with in vivo measures of function (back motion and muscle activity) will be investigated in further studies.     

Age-related changes in metabolic properties of equine skeletal muscle associated with muscle plasticity

The purpose of the present study was to determine the age-related changes in myosin heavy chain (MHC) composition and muscle oxidative and glycolytic capacity in 18 horses ranging in age from two to 30 years. Muscle samples were collected by excisional biopsy of the semimebranosus muscle. MHC expression and the key enzymatic activities were measured. There was no significant correlation between horse age and the proportions of type-IIA and type-IIX MHC isoforms. The percentage of type-I MHC isoforms decreased with advancing age. Muscle citrate synthase activity decreased, whereas lactate dehydrogenase activity increased with increasing age. Muscle 3-OH acyl CoA dehydrogenase activity did not change with ageing. The results suggest that, similar to humans, the oxidative capacity of equine skeletal muscle decreases with age. The age-related changes in muscle metabolic properties appear to be consistent with an age-related transition in MHC isoforms of equine skeletal muscle that shifts toward more glycolytic isoforms with age.     

Changes in the muscle fibre properties of the mouse temporal muscle after weaning

To clarify changes in the muscle fibre properties of the temporal muscle related to the start of masticatory movement, we immunohistochemically investigated myosin heavy chain (MyHC) isoform protein expression using pre-weaning and post-weaning mice. In addition, we examined the expression of a gene coding for those MyHC proteins. Immediately after weaning, isoforms with fast and potent contractility were frequent. This suggests that the temporal muscle plays an important role in a marked functional change in the oral cavity from lactation to mastication, contributing to oral function in cooperation with other masticatory muscles.     

Electrophoresis of avian muscle proteins

1. The electrophoretic patterns of water‐soluble proteins of avian muscle showed differences due both to species and to muscle type.

2. Each muscle pattern within a species showed a unique protein band which distinguished that species from other species.