NFATc3基因在不同品种鸡骨骼肌中的mRNA表达分析

活化T细胞核因子3(Nuclear factor of activated T cells 3,NFATc3)是NFAT家族的重要成员,在肌纤维类型转换中具有重要的作用。为探讨NFATc3 mRNA在不同品种鸡不同类型肌肉中的表达情况,以生长速度具有较大差异的清远麻鸡和隐性白羽鸡为材料,采用实时荧光定量PCR方法,检测不同发育时期趾长伸肌和比目鱼肌中NFATc3 mRNA的表达情况。结果发现,NFATc3 mRNA在两个品种骨骼肌的变化趋势基本一致,1日龄时,NFATc3在趾长伸肌和比目鱼肌中的表达量都较高,7日龄时显著下降,21日龄时出现上升,之后表达量趋于平稳;品种间比较,比目鱼肌中在21、49日龄时,清远麻鸡的基因表达量显著高于隐性白羽鸡(P0.05),趾长伸肌中则在1、21日龄时,清远麻鸡的基因表达量显著高于隐性白羽鸡(P0.05);同一品种不同类型肌肉间比较,总体上都是趾长伸肌的表达量高于比目鱼肌。提示,鸡骨骼肌中NFATc3 mRNA表达变化规律不存在品种差异,NFATc3可能在鸡不同类型肌肉肌纤维的发育中起重要作用。     

PGC-1β基因在鸡骨骼肌中的表达差异研究

为探讨PGC-1β基因在鸡骨骼肌中的表达情况,研究利用实时荧光定量PCR法检测了慢生型清远麻鸡和速生型隐性白羽鸡的比目鱼肌(主要含慢肌纤维)和趾长伸肌(主要含快肌纤维)PGC-1βm RNA的发育性表达变化。结果表明,清远麻鸡从0~9周龄,比目鱼肌和趾长伸肌的PGC-1βm RNA表达均呈"W"的趋势,比目鱼肌在0周龄时表达最高、5周龄时表达最低,趾长伸肌在9周龄时表达最高、7周龄时表达最低;隐性白羽鸡比目鱼肌呈"先升后降再升"的表达趋势,1周龄时出现峰值、7周龄时表达最低,趾长伸肌在3周龄时表达最高,显著高于其他各周龄(P0.05),其他各周龄间差异不显著(P0.05);相同周龄清远麻鸡比目鱼肌和趾长伸肌PGC-1βm RNA表达水平低于隐性白羽鸡。结果提示,鸡骨骼肌PGC-1βm RNA表达发育模式具有品种、年龄和表型特异性,并可能与肉品质存在关联。     

CaN/NFAT信号通路相关基因在鸡骨骼肌中的表达规律及关联分析

旨在探讨CaN/NFAT信号通路相关基因在鸡生长发育早期不同表型骨骼肌中的表达规律以及各基因之间的调控联系。利用荧光定量PCR技术检测隐性白羽鸡2种表型骨骼肌(腓肠肌外侧头和趾长伸肌)中CaN/NFAT信号通路相关基因(CnAα、CnB1、NFATc3、MEF2C和PPARGC1A)在出生后不同生长阶段(0、1、3、5、7和9周龄)的相对表达,并对这些基因的表达进行相关性分析。结果表明,除CnB1基因外,其他4个基因mRNA在2种表型骨骼肌中的表达趋势均较相似;2种表型骨骼肌中5个基因的表达从7周龄到9周龄均呈上升的趋势;同周龄2种表型骨骼肌相比,除腓肠肌外侧头PPARGC1A基因各周龄表达均高于趾长伸肌外,其他4个基因表达均是在3周龄时腓肠肌外侧头高于趾长伸肌,而在7和9周龄时则低于趾长伸肌;相关分析结果表明,除CnAα与NFATc3、CnAα与PPARGC1A基因的表达在2种表型肌肉中呈负相关外,其余各基因表达之间均呈正相关。提示,鸡骨骼肌CnAα、CnB1、NFATc3、MEF2C和PPARGC1A基因表达发育模式具有年龄和表型特异性,可能参与调控鸡骨骼肌肌纤维的生长和类型转换。     

不同品种、饲养周期肉鸡肉品质和风味的比较分析

本试验旨在比较不同品种肉鸡在体重、常规肉品质及肌间脂肪、氨基酸和脂肪酸含量的差异,以期为肉鸡肉品质评价指标的建立提供参考。分别选取同日龄、同饲养条件下的快大型鸡(隐性白羽肉鸡、安卡鸡)和地方品种鸡(文昌鸡、北京油鸡、清远麻鸡)作为研究素材,选取接近平均体重的9周龄快大型鸡和17周龄地方品种鸡各60只,称重、屠宰,用于不同品种胸肌常规肉品质及肌间脂肪、氨基酸和脂肪酸含量的测定;另选取9和17周龄的隐性白羽肉鸡各60只称重、屠宰,用于不同饲养周期胸肌常规肉品质及肌间脂肪、氨基酸和脂肪酸含量的测定。结果表明:1)不同品种出栏时期比较,安卡鸡的体重显著高于其他品种(P0.05),北京油鸡的胸肌失水率显著低于其他品种(P0.05),文昌鸡、清远麻鸡的胸肌剪切力显著低于安卡鸡、北京油鸡(P0.05),安卡鸡的胸肌肉色显著高于其他品种(P0.05),北京油鸡的胸肌pH显著高于其他品种(P0.05),文昌鸡的胸肌肌间脂肪含量显著高于其他品种(P0.05)。清远麻鸡的胸肌必需氨基酸、非必需氨基酸、鲜味氨基酸、甜味氨基酸、总氨基酸含量均显著高于其他品种(P0.05),隐性白羽肉鸡、安卡鸡的胸肌饱和脂肪酸含量显著高于其他品种(P0.05),隐性白羽肉鸡、北京油鸡的胸肌必需脂肪酸含量显著高于其他品种(P0.05),隐性白羽肉鸡的胸肌不饱和脂肪酸含量最高。2)不同饲养周期比较,隐性白羽肉鸡9周龄胸肌的失水率及非必需氨基酸、鲜味氨基酸、饱和脂肪酸、必需脂肪酸含量显著高于17周龄(P0.05),体重、胸肌pH、胸肌肌间脂肪含量显著低于17周龄(P0.05)。由此可知,不同品种肉鸡的肉品质、风味物质含量差异较大,不能用单一的指标进行衡量。从肉品质的营养角度分析,9周龄出栏的快大型肉鸡优于17周龄。     

鸡成肌细胞及不同品种肌肉组织的FAFFAF1 mRNA表达特征分析

以矮小品系S2系鸡和隐性白羽鸡作为试验素材,采用q-PCR技术及SPSS分析软件,研究Fas相关因子1(Fas-associated factor 1,FAF1)在两个品种胚胎期至生长期骨骼肌发育中的差异性的表达模式及在成肌细胞增殖和分化期的表达特征。结果表明,FAF1在两品种胚胎期胸肌组织的表达都显著高于出雏后其他发育时期(P0.05),但FAF1在S2系鸡整个胚胎期及出雏当天的表达都显著高于隐性白羽鸡(P0.05);在腿肌组织中,隐性白羽鸡中,在10日胚龄时FAF1的表达量显著高于其他胚龄(P0.05),并随胚龄的增加表达量逐渐下降,在6周龄时表达量显著低于2、4、8、16周龄(P0.05),S2系鸡中,10日胚龄时FAF1的表达量显著高于其他发育时期(P0.05),从胚胎期至出雏后6周表达量随周龄的增加逐渐减少。除6周龄外,FAF1在S2系鸡其他发育时期的表达都显著高于隐性白羽鸡。在鸡原代成肌细胞中,FAF1 mRNA 在分化期的表达显著高于增殖期(P0.05),并随诱导分化时间的延长表达量逐渐升高。结果表明:FAF1 mRNA 表达呈现明显的品种和组织差异性,该基因可能以不同的方式参与调控胸肌、腿肌发育过程,为进一步研究该基因调控肌肉发育的分子机制提供了理论依据。     

隐性白羽鸡与清远麻鸡生长曲线及相关性研究

为充分挖掘品种资源生长潜力,以清远麻鸡和国外引进的快大型品种隐性白羽鸡为研究对象,用Logistic模型、Gompertz模型和Von Bertalanffy模型对体重和胫长进行了生长曲线的拟合,并比较了3种模型拟合效果的优劣。结果表明,体重用Gompertz和Von Bertalanffy模型拟合效果较好,胫长用Logistci模型拟合效果较好。2周龄体重、3周龄胫长与3～14周龄体重极显著,r值为0.8。通过对早期体重和胫长的个体选择,可达到上市日龄较大体重的要求。     

CSRP3基因在鸡胚胎期胸肌、成肌细胞中的表达及其与胸肌质量的相关性研究

为研究CSRP3在鸡骨骼肌早期生长发育中的作用，本研究通过实时荧光定量PCR技术探讨了CSRP3mRNA在生长速度不同的花山鸡和清远麻鸡胚胎期胸肌中以及体外培养的鸡成肌细胞中的表达，并分析2个品种鸡胚胎期胸肌中CSRP3 mRNA的表达与其胸肌质量、体质量的相关性。体内外研究结果均表明，CSRP3基因的表达随着鸡骨骼肌肌纤维分化进程逐渐升高；同一胚龄时，比较CSRP3mRNA在2个品种鸡胸肌中的表达，均是慢生型清远麻鸡显著高于快大型花山鸡；相关性结果表明，2个品种鸡胚胎期胸肌中CSRP3mRNA表达量与其胸肌质量、体质量均呈正相关，与胸肌质量的相关性达极显著水平。结果提示，鸡胸肌中CSRP3基因的表达具有品种特异性，与胸肌肌纤维的生长和分化有着密切联系。     

清远麻鸡与隐性白羽鸡杂交试验研究

以清远麻鸡为父本,隐性白羽鸡为母本进行杂交,测定其后代的繁殖性能、蛋的品质、体尺测量及饲料报酬等,并对之进行分析.结果表明,杂交一代无论是繁殖性能还是饲料报酬等均优于清远麻鸡,而肉质风味则酷似清远麻鸡,并且保持了清远麻鸡的外貌特征.     

基于主成分分析的不同品种鸡肉品质评价

本研究旨在利用主成分分析法对不同品种鸡的肉品质进行综合评价,为鸡肉品质评价标准的建立提供参考.选用常规方法对隐性白羽肉鸡、安卡鸡、文昌鸡、北京油鸡、清远麻鸡5个不同品种鸡肉的pH、肉色、失水率、剪切力、肌内脂肪、氨基酸、脂肪酸含量等指标进行测定,利用主成分分析法建立不同品种鸡肉品质评价模型,利用该模型对5个品种鸡肉品质...     

提高鸡肉品质的方法

一、选择合适品种 三黄胡须鸡、杏花鸡、清远麻鸡、沙栏鸡肉质优;隐性白羽鸡、快大型仔鸡等肌肉纤维相对较粗,品味欠佳。 二、提供优质饲料 饲料成分是影响鸡肉品质的最直接的因素,鸡肉的味道受其摄食的饲料影响最大。因此,在提高鸡肉的品质时,除了遗传育种的技术外,对于生长期,尤其是后期上市前饲喂的日粮配     

基于连接酶检测反应的并行分型系统检测鸡肉风味相关候选基因多态性

旨在建立一个基于聚合酶链反应—连接酶检测反应(LDR)的基因多态性并行检测系统,检测鸡肉风味相关候选基因脂肪型脂肪酸结合蛋白(A-FABP)基因、细胞外脂肪酸结合蛋白(Ex-FABP)基因和腺苷琥珀酸裂解酶(ADSL)基因的多态性,并分析其在优良地方鸡种——清远麻鸡和快大型隐性白羽鸡中的分布差异。采集165只隐性白羽鸡和185只清远麻鸡母鸡的血液并提取DNA,应用PCR-LDR方法检测A-FABP51C/T、Ex-FABP1011T/C和ADSL3484C/T的基因型。结果,所得分型结果同直接测序分型结果一致。3个多态位点在2个品种鸡中均表现为中度多态,并且在不同品种中的分布均存在差异,在A-FABP51C/T位点上达到显著水平。结果表明,建立的基于连接酶检测反应的基因多态性并行检测系统是一种准确、灵敏的SNP检测方案,为鸡肉风味性状相关基因的多态性研究提供了基础。     

鸡肉嫩度候选基因CAPN1多态性的检测研究

建立基于聚合酶链反应-连接酶检测反应的基因多态性并行检测系统,探讨鸡肉嫩度候选基因钙蛋白酶I（CAPN1）基因的多态性,并分析其在优良地方鸡种-清远麻鸡和快大型隐性白羽鸡中的分布差异。用PCR-LDR方法检测CAPN1 2546、CAPN1 3535和CAPN19950的基因型作单倍型分析,进行各组间基因型分布和等位基因频率x2检验。结果CAPN12546位点未检测到多态,其他两个位点的结果同直接测序分型结果一致,其基因型分布在不同品种中均存在差异,并且在CAPN1 3535位点上达到显著水平,两个位点的单倍型分布在不同品种间也存在较大差异。     

IGFBP-3基因在两个品种鸡组织中的表达及其与生长性状的相关性分析

为研究IGFBP-3基因表达与鸡生长性状的相关性,以生长速度差异较大的花山麻鸡和清远麻鸡两个黄羽肉鸡品种为研究素材,用实时荧光定量PCR法检测胚胎期和出雏后两个品种鸡胸肌和肝脏中IGFBP-3基因的表达规律,并将其与体重、胸肌重和肝脏重进行相关性分析。结果表明,在9胚龄时两个品种鸡胸肌和肝脏中均可检测到IGFBP-3基因表达,同一胚龄或日龄品种内组织间比较,胚胎期两个品种鸡胸肌IGFBP-3 mRNA表达量均高于肝脏,出雏后肝脏IGFBP-3 mRNA表达量迅速上升,胸肌IGFBP-3 mRNA表达量下降,两个品种鸡肝脏IGFBP-3 mRNA表达量均极显著高于胸肌（P<0.01）;组织中IGFBP-3 mRNA表达量与组织重量和体重相关研究表明,两个品种鸡肝脏IGFBP-3 mRNA表达量与其胸肌重、肝脏重和体重呈显著或极显著正相关（P<0.05;P<0.01）,胸肌IGFBP-3 mRNA表达量与其胸肌重、肝脏重和体重均呈极显著负相关（P<0.01）。研究结果揭示,IGFBP-3 mRNA在鸡中的表达具有品种、年龄和组织特异性,出雏前肝脏并不是鸡产生IGFBP-3的主要器官,出雏后鸡IGFBP-3可能主要由肝脏合成,肝脏中IGFBP-3 mRNA水平差异是导致两个品种鸡出雏后体重和胸肌重差异的重要因素。     

METTL16在鸡不同类型肌肉中的表达规律及其对肌肉功能的调控作用

旨在了解m6A甲基转移酶样蛋白16(methyltransferase-like protein 16,METTL16)在鸡不同类型肌肉组织中的表达情况及其在鸡骨骼肌功能中的调控作用。本研究利用qRT-PCR技术检测METTL16基因在120日龄广西麻鸡母鸡不同类型肌肉组织中的表达,同时利用siRNA干扰鸡原代成肌细胞中METTL16基因的表达,分析其对成肌细胞增殖、分化和肌纤维形成的影响。结果显示,METTL16基因在鸡的不同类型肌肉组织(胸大肌、胸小肌、缝匠肌、耻坐骨肌内侧肌、耻坐骨肌外侧肌、髂胫外侧肌、腓肠肌内侧肌和背阔肌)中广泛表达,其中,在白肌纤维为主的胸大肌、胸小肌和髂胫外侧肌中表达量相对更高;细胞增殖检测结果显示,干扰METTL16基因表达后,鸡成肌细胞的增殖活力受到了抑制;在成肌细胞分化后干扰METTL16基因表达,鸡成肌细胞RNA m6A甲基化水平呈下降趋势,细胞分化关键基因MyoD表达显著下降(P<0.05),fast-MyHC基因表达显著上升(P<0.001),slow-MyHC基因表达呈下降趋势。综上,METTL16基因在不同类型肌肉中的表达与其肌纤...     

Cold exposure increases slow‐type myosin heavy chain 1 (MyHC1) composition of soleus muscle in rats

The aim of this study was to examine the effects of cold exposure on rat skeletal muscle fiber type, according to myosin heavy chain (MyHC) isoform and metabolism‐related factors. Male Wistar rats (7 weeks old) were housed individually at 4 ± 2°C as a cold‐exposed group or at room temperature (22 ± 2°C) as a control group for 4 weeks. We found that cold exposure significantly increased the slow‐type MyHC1 content in the soleus muscle (a typical slow‐type fiber), while the intermediate‐type MyHC2A content was significantly decreased. In contrast to soleus, MyHC composition of extensor digitorum longus (EDL, a typical fast‐type fiber) and gastrocnemius (a mix of slow‐type and fast‐type fibers) muscle did not change from cold exposure. Cold exposure increased mRNA expression of mitochondrial uncoupling protein 3 (UCP3) in both the soleus and EDL. Cold exposure also increased mRNA expression of myoglobin, peroxisome proliferator‐activated receptor gamma coactivator 1α (PGC1α) and forkhead box O1 (FOXO1) in the soleus. Upregulation of UCP3 and PGC1α proteins were observed with Western blotting in the gastrocnemius. Thus, cold exposure increased metabolism‐related factors in all muscle types that were tested, but MyHC isoforms changed only in the soleus.     

余干黑羽乌鸡血型基因种群遗传差异分析

应用中国科学院遗传研究所研制的１１个抗鸡红细胞抗原单价血清，对江西省余干黑乌鸡进行了血型测定和群体遗传学分析，并与江西其他三个地方良种鸡（泰和鸡、白耳鸡、崇仁麻鸡）的血型测定资料一起进行分析。结果表明：余干黑羽乌鸡群体的均一性好，整齐度高，达到了较高的选育水平；余干黑羽乌鸡的血型基因分布频率除与崇仁麻鸡没有显著差异，遗传距离最近外，与泰和鸡和与白耳鸡之间遗传距离均较远，遗传差异较大，说明余干黑羽乌鸡是一个具有突出特点的独立地方鸡种     

New alleles of chicken CD8 alpha and CD3d found in Chinese native and western breeds

Chinese native chicken breeds provide useful resources for the study of genetic diversity. In this study, the alleles of CD8 alpha and CD3d cDNA from Chinese native and introduced western breeds of chicken were analyzed at the sequence level. Six alleles were found, due to 13 amino acid replacements in the extracellular domain of the CD8 alpha sequence. There were four alleles detected in the Chinese strains, and alleles 5 and 6 were identified for the first time. Allele 6 was shared by Langshan, Beijing Fatty and Recessive White Feather chickens. Allele 2, found in the Bigbone strain, was the same as that found in the Leghorn strain H.B15.H7, and allele 3 in the Xianju breed was also the same as in the Leghorn strain H.B15.H12. Two Leghorn lines (RPL line 7 and AY519197) and the Camellia possessed an allele (alleles 1, 4 and 5), respectively, that was not found in the other lines. Nine out of 13 amino acid replacements were situated in the putative major histocompatibility complex (MHC) class I binding CDR1 (positions 30, 33 and 34), CDR2 (positions 58, 62, 63 and 65) and CDR3 (positions 90 and 106). Except for the Xianju breed, the CD8 alpha cDNA of Chinese native chicken breeds shared high homology. Two alleles were found in CD3d. Three additional nucleotides were found at positions 64, 65 and 66 in the newly discovered allele 2. This led to a difference of four amino acids (at residues 22, 23, 24 and 25) in the extracellular domain of CD3d cDNA from the Gushi, Recessive White Feather and ISA chickens compared with these of the White Leghorn and T11.15 (NM_205512). Five hybridoma clones (1C9, 1H5, 4B11, 6G5 and 13C5) against chicken CD8 alpha were generated by DNA immunization. Two monoclonal antibodies (mAbs), 6G5 and 4B11, showed reactivity to the splenocytes from five Chinese native chicken breeds, the Recessive White Feather chicken and the Leghorn (AY519197), while mAbs 1C9, 1H5 and 13C5 showed no reaction with these breeds.     

Avulsion of the origin of the tendon of the extensor digitalis longus muscle in a Dobermann pinscher

Avulsion of the tendon of the extensor digitalis longus muscle is a rare condition in young, large breed dogs or as a consequence of chronic lateral patellar luxation in adult dogs. Current technique of fixation consists into reattaching the fragment with a lag screw at its origin in the extensor fossa of the lateral femur condyle. If the fragment was considered too friable and reactive to be reattached, it was amputated and the tendon was sutured to the joint capsula. In this present case a adaptation screw with a washer was inserted distally to the sulcus extensorius through the tendon. The proximal part of the tendon was sutured to the joint capsula. The postoperative result was excellent, with recovery of full function of the Musculus extensor digitalis longus.     

The leucine metabolite 3-hydroxy-3-methylbutyrate (HMB) modifies protein turnover in muscles of laboratory rats and domestic chickens in vitro

This study was conducted to assess the in vitro effects of leucine and 3-hydroxy-3-methylbutyrate (HMB) on protein synthesis and degradation in isolated rat and chick muscles. Isolated muscles — extensor digitorum longus (EDL) and soleus (S) in rats and EDL and tibialis anterior (TA) in chicks — were taken out intact and incubated in Krebs—Henseleit buffer with [¹⁴C]phenylalanine. Protein synthesis was then determined by measuring [¹⁴C]phenylalanine incorporation into protein and protein breakdown was estimated by net release of tyrosine from muscle proteins. In all muscles investigated leucine stimulated protein synthesis (average 20%; p < 0.05 versus control) but only slightly reduced proteolysis (average 8%, NS). In contrast, HMB had no significant effect on protein synthesis but consistently decreased protein degradation in the range from −29% (p < 0.01 versus control) in rat extensor digitorus longus to −5% (NS) in rat soleus muscles. HMB appeared to suppress protein degradation more in white muscle fibres than in red muscle fibres (at least in the rat). These data support observations in humans indicating that HMB decreases muscle proteolysis. It is suggested that metabolism of leucine to HMB could be responsible for the reported suppressive effects of leucine on protein breakdown.