利草F_1与草原红牛肉用性能比较试验研究

为了进一步研究利木赞杂交草原红牛的肉用性能,选择断奶后小公牛利草F139头、草原红牛79头,在同样的饲养管理条件下,持续育肥至18月龄时屠宰。结果表明,利草F1出栏体重和育肥期日增重极显著地高于草原红牛（P〈0.01）;体躯高度、体斜长、坐骨端宽、胸围、管围、腿围均极显著地大于草原红牛（P〈0.01）,整体结构趋向于偏肉体型;胴体重、屠宰率、净肉率等主要产肉指标极显著地高于草原红牛（P〈0.01）;利草F1肉中的粗脂肪含量较草原红牛有一定的下降,而粗蛋白质的含量有所上升;利草F1的油酸含量比草原红牛下降2.43个百分点;不饱和脂肪酸、与鲜味有关的氨基酸和必需氨基酸总量,利草F1与草原红牛没有明显的变化。     

利木赞杂种一代牛育肥效果试验

通过利木赞杂种一代牛不同方式育肥试验结果表明,在科学饲养管理条件下,利木赞杂种一代牛的平均日增重、屠宰率、净肉率及肉的品质都有明显的提高.杂种一代牛的平均日增重在放牧期和舍饲期,比相同饲养条件下的草原红牛分别增加161 g和180 g,屠宰率和净肉率均高于草原红牛.     

利木赞牛杂交改良对草原红牛肉质的影响

将纯种草原红牛和含1/2利木赞血缘的改良草原红牛各16头在相同营养水平和饲养条件下进行10个月的集中舍饲育肥，研究了2组牛生长速度、产肉率及眼肌面积、大理石花纹和嫩度等肉质水平。结果显示, 改良牛的体高、体长、胸围、体质量、增重、屠宰率和净肉率等极显著或显著地高于草原红牛（P<0.01或P<0.05），改良牛的眼肌面积比草原红牛增8.39%，大理石花纹等级和嫩度剪切力值也略大于草原红牛，但差异均不显著(P>0.05)。试验结果表明，利木赞牛对草原红牛的肉用性能改良效果显著，且对草原红牛的肉质没有明显影响,草原红牛保持了其原有肉质好的品种特性。     

吉林省中国草原红牛培育及选育提高进程

作者介绍了中国草原红牛的培育过程及育成后的选育提高进程。经选育后的吉林中国草原红牛（含1/4丹麦红牛血）3胎泌乳期244.39 d,提高9.59%;产奶量（3～5胎平均）3145.88 kg,提高了89.21%;最高个体产量5329.85 kg,提高了59.34%。在相同饲养条件下,含1/4利木赞血的吉林中国草原红牛胴体重提高8.13%,屠宰率提高3.24%,净肉率提高4.57%,眼肌面积提高15.25%,骨率变化不大,胴体脂肪覆盖度略有下降,牛肉中氨基酸、脂肪酸含量变化不明显。     

草原红牛MSTN基因第一外显子SNPs多态性分析

根据牛的肌肉生长抑制素基因（myostatin,简写为MSTN）外显子1的序列设计引物，用PCR—SSCP方法对草原红牛和利木赞与草原红牛的杂交牛进行了单核苷酸多态性分析，并检测到了多态性，表现为从、BB和AB3种基因型。对两种纯合子进行测序，结果发现282位碱基发生突变，由C突变为A，导致编码的氨基酸由苯丙氨酸变为亮氨酸。经独立性检验发现基因频率和基因型频率的分布与含利木赞血液的多少有关；并通过不同性状在该位点不同基因型间的显著性检验表明，等位基因B可以显著的提高草原红牛的日增重、屠宰率、净肉率和肉骨比。     

草原红牛导血后产肉性能分析

草原红牛导入丹麦红牛血液后，其杂交后代（Ｆ２、Ｆ３）的产肉性能比草原红牛有所提高（经Ｆ检验，差异不显著Ｐ＞０．０５）；导血后，净肉率Ｆ２、Ｆ３比草原红牛分别高出１．５和３个百分点，优质肉块产量也比导血前高，同月龄牛宰前活重、屠宰率和骨量的变化不大。     

不同品种肉牛育肥效果的比较试验报告

对21～23月龄的12头西门塔尔、夏洛来、利木赞、安格斯与黄牛级进杂交二代优质改良牛进行60d强度育肥,测定分析4个品种牛的生长指标、屠宰指标、肉的品质3个指标,并进行差异显著性分析。在生长指标上西门塔尔平均日增重1506g,夏洛来平均日增重为1390g,利木赞平均日增重为1054g,安格斯平均日增重为823g。结果表明,西门塔尔和夏洛来之间差异不显著,其他之间差异均极显著。在屠宰指标上,西门塔尔屠宰率为57.86%,净肉率为50.22%,肉骨比6.57,夏洛来屠宰率为60.28%,净肉率为51.47%,肉骨比5.41,利木赞屠宰率为57.80%,净肉率为50.48%,肉骨比为6.91,安格斯的屠宰率为57.48%,净肉率为48.81%,肉骨比为5.67。结果表明夏洛来的屠宰率与西门塔尔、利木赞、安格斯之间差异极显著,其他品种之间差异不显著。对净肉率而言,夏洛来、利木赞、西门塔尔与安格斯之间差异极显著;夏洛来与西门塔尔、利木赞之间差异显著;利木赞与西门塔尔之间差异不显著。各品种的肉骨比差异不显著。在肉品质这一指标上,嫩度、眼肌面积、优质肉的比例中西门塔尔最佳。     

黄原红牛导血后产肉性能分析

草原红牛导入丹麦红牛血液后，其杂交后代（Ｆ２、Ｆ３）的产肉性能比草原红牛有所提高（经Ｆ检验，差异不显著Ｐ〉０．０５），导血后，净肉率Ｆ２，Ｆ３比草原红牛分别高出１．５和３个百分点，优质肉块产量也比导血前高，同月龄牛宰前活重，屠宰率和骨量的变化不大。     

幼龄商品肉牛产肉力的研究

３个品种牛的育肥实验和屠宰实验证明，在科学饲养管理条件下，幼龄牛的日增重，屠宰率，净肉率及肉的品质都有明显的提高，夏洛来牛的产肉力最好。在平均日增重上，夏洛来牛比西门塔尔牛和草原红牛分别增加１４８ｇ和２１２ｇ，差异极显著；西门塔尔牛比草原红牛的平均日增重增加６４ｇ，差异显著。     

发酵桑叶对湘西黄牛×利木赞杂交F1代育肥牛屠宰性能、肉品质及肌肉中氨基酸、脂肪酸含量的影响

本试验旨在研究不同添加比例发酵桑叶对湘西黄牛×利木赞杂交F1代育肥牛屠宰性能、肉品质及肌肉中氨基酸、脂肪酸含量的影响。试验选取20头12～15月龄健康湘西黄牛×利木赞杂交F1代公牛,随机分为4个组,每组5个重复,每个重复1头牛。各组饲粮中发酵桑叶添加比例分别为0(CG组,对照组)、10%(LG组)、20%(MG组)和30%(HG组)。预试期10 d,正试期90 d。结果表明:1)HG组屠宰率和净肉率为59.07%、47.35%,屠宰率比CG、LG和MG组分别提高了0.64%、1.89%和1.00%,净肉率分别提高了0.47%、0.58%和0.41%,但差异不显著(P0.05)。与CG组相比,LG、MG和HG组眼肌面积分别提高了10.21、9.97、11.97 cm~2。2)各组间肌肉干物质、粗蛋白质、粗脂肪、粗灰分含量均无显著差异(P0.05)。HG组肌肉剪切力显著低于CG、LG和MG组(P0.05),HG组肌肉滴水率显著高于CG、LG和MG组(P 0.05),LG、MG组肉肌肉失水率显著低于CG和HG组(P0.05)。3)各组间肌肉中总氨基酸和脂肪酸含量均无显著差异(P0.05)。HG组肌肉中苏氨酸、蛋氨酸、酪氨酸含量显著高于CG、LG和MG组(P0.05),HG组的肌肉必需氨基酸评分更接近联合国粮农组织(FAO)理想模式。由此可见,饲粮中添加发酵桑叶对湘西黄牛×利木赞杂交F1代公牛的屠宰性能、肉品质以及肌肉中氨基酸、脂肪酸含量的提升有一定的促进作用。     

湘西黄牛杂交组合育肥及肉质性能研究

选取18月龄湘西黄牛、西本（西门塔尔牛×湘西黄牛）、利本（利木赞牛×湘西黄牛）、西西本（西门塔尔牛×西本）、利西本（利木赞牛×西本）共24头,于舍饲条件下补饲精料,进行70d的育肥试验。结果表明：利西本三元杂交牛的增重水平和育肥效益明显优于其他组合和湘西黄牛,利西本三元杂交牛的日增重1.21 kg;屠宰率58.44%,净肉率47.68%;胴体质量与产量等级评定表明：利西本三元杂交牛牛肉指标达到了特级标准;产量达到了国内优质高档牛肉的重量标准。肉质特性测定表明：利本杂交牛肉品大理石纹较为丰富,利西本杂交牛肉品较细嫩、柔软;各组合间氨基酸含量差异不显著（P〉0.05）,而利西本和湘西黄牛臀肌总氨基酸含量、必需氨基酸含量显著高于背肌（P〈0.05）,其他组合间差异不显著（P〉0.05）。     

草原红牛与利木赞杂交后增重效果的观察

草原红牛育成后，肉用性能亟待提高，因此我们搞了用利木赞杂交的试验。试验从草原红牛与利木赞杂交后的育肥效果观察，可以看出：杂交后利×草Ｆ１的增重效果明显优于草原红牛，且适合于草原地区放牧饲养，此杂交组合应当予以推广     

草原红牛改良群体H FABP基因SNP及其与肉质性状的相关分析

试验采用PCR-SSCP的方法对含1/2利木赞血缘的改良草原红牛的H-FABP基因5’-调控区进行SNP分析,并分析其多态性与改良草原红牛肉质性状的相关性。结果表明：改良草原红牛H-FABP基因5’-调控区存在多态位点,在136位点发生1个T碱基的插入突变,在142位点,发生了G→A转换。相关分析结果显示剪切力在AA和AB、BB基因型间差异极显著（P<0.01）,AB与BB基因型间差异不显著（P>0.05）,A基因对剪切力有负效应,其余肉质性状在不同基因型间差异均不显著（P>0.05）。表明H FABP基因对改良草原红牛肉质嫩度有显著影响。     

贵州不同杂交肉牛生产性能的研究

为了探讨西门塔尔牛、安格斯牛、利木赞牛改良本地黄牛的效果,选取18～20月龄,体重280±15.8 kg的西本杂、安本杂及利本杂F1代公牛各20头,按品种分为3组;以青贮玉米和白酒糟为基础粗料,经过6个月的集中肥育,研究杂交肉牛肥育效果与品种的关系,进而分析各项屠宰指标.结果表明：西本杂的平均日增重和料肉比最高,利本杂的日增重和料肉比最低;西本杂、安本杂的宰前活重、胴体重、屠宰率和高档肉重与利本杂相比,差异极显著（P＜0.01）,净肉率和骨肉比值差异显著（P＜0.05）;3组试验牛的大理石纹等级和背膘厚度差异不显著（P＞0.05）.     

Characterization of topcross progenies from Hereford, Limousin, and Piedmontese sires

Breeds of larger mature size tend to grow more rapidly and be older when attaining a given level of fatness. Hereford, Limousin, and Piedmontese are of approximately equal mature size and yet may vary in body composition at a given degree of maturity. However, direct comparisons among these three breeds were not found. Therefore, the objective of this research was to compare Hereford, Limousin, and Piedmontese progenies for economically important traits. Crossbred cows were bred to Hereford (n = 23), Limousin (n = 24), or Piedmontese (n = 24) sires. Male calves were either left intact or castrated at approximately 2 mo of age. Calves remained with their dams until weaning at an average age of 179 d. Male calves were then individually fed a growing ration until they reached 386 kg and then fed a finishing ration either 90 or 132 d. They were then slaughtered at a commercial abattoir and carcass data were collected. Female calves were group-fed and used to examine nutritional effects on age at puberty. Data were analyzed using REML and linear contrasts among the breed-of-sire effects evaluated. Herefordsired calves had shorter gestation periods and weighed less at birth than either Limousin- or Piedmontese-sired calves. Calving difficulty of Hereford- and Limousin-sired calves was less than that of Piedmontese-sired calves. Limousin-sired calves tended to grow more rapidly than Hereford-sired calves. By the finishing phase, Limousin- and Hereford-sired calves had greater average daily gains than Piedmontese-sired calves. Differences in dry matter intake among breeds of sire were relatively small. Differences in carcass weight, longissimus muscle area, fat depth, and percentage kidney, pelvic, and heart fat resulted in a clear stratification of USDA yield grade between breeds of sire. Differences in percentage primal cuts were similar to those for USDA yield grade. Hereford-sired calves had more marbling than progeny of Limousin or Piedmontese sires. However, the force necessary to shear cores from steaks of Piedmontese-sired calves was less than for progeny of Limousin or Hereford sires. Hereford- and Piedmontese-sired heifers were younger at puberty than Limousin-sired heifers. Within breeds of similar mature size and growth rate, ample variation exists in age at puberty and body composition at an approximately equal degree of maturity.     

Comparative Study on the Beef Traits Between Jiaxian Red Cattle and Crossbred Beef Cattle

In order to study the beef traits and beef quality of Jiaxian Red bull with crossbred beef cattle, 5 purebred Jiaxian Red bull, 5 Red Angus cattle×Jiaxian Red bull F1 generation, 5 Simmental cattle×Jiaxian Red bull F1 generation and 5 Charolais cattle×Jiaxian Red bull F1 generation were chosen and assigned into groups A,B,C and D for continual finishing for 3 months of age under the same feeding and management conditions and slaughtered at the end of the trial. The results showed that there were no significant difference in body height, body length, chest girth and cannon circumference between Red Angus cattle×Jiaxian Red bull F1 generation and purebred Jiaxian Red bull, the same as in Charolais cattle×Jiaxian Red bull F1 generation (P>0.05). The weight of head, skin, fore hooves and tail, the skin thick, esophagus, trachea, liver, spleen, lung, kidney, and carcass meat percentage, loin eye area and the meat bone ratio in crossbred beef cattle groups were not significant differences compared with purebred Jiaxian Red bull (P>0.05), but its hind legs wide in carcass was significantly higher than that of purebred Jiaxian Red bull (P<0.05). The high-grade meat weight and high quality meat weight in Red Angus cattle×Jiaxian Red bull F1 generation were 70.22 and 105.22 kg, respectively, and was the highest in four groups,but the high-grade beef percentage among four groups did not show significant differences (P>0.05). The high quality meat percentage in Red Angus cattle×Jiaxian Red bull F1 reached 34.43%, was significantly higher than that of Jiaxian Red bull and Simmental cattle×Jiaxian Red bull F1 generation (P<0.05), and was higher than that of Charolais cattle×Jiaxian Red bull F1 generation (P>0.05). In terms of meat quality, the content of inosinic acid that related with the meat flavor in Red Angus cattle×Jiaxian Red bull F1 was the highest in four groups, while the content of unsaturated fatty acid and the flavor related amino acid, such as aspartic acid, glutamic acid, glycine and alanine, in Charolais cattle×Jiaxian Red bull F1 were the highest in four groups,and their values were 53.85% and 8.04%, respectively. To sum up, the results suggested that there was no significant difference in body development and beef traits using Red Angus cattle, Simmental cattle and Charolais cattle to improve Jiaxian Red bull, while Red Angus cattle crossbred with Jiaxian Red bull could moderately improve the weight of high-grade beef and high-quality beef, and Charolais cattle could moderately improve the beef quality of Jiaxian Red bull.     

郏县红牛与不同品种肉牛杂交后代肉用性能比较研究

为了研究郏县红牛与不同品种肉牛杂交后代的肉用性能和肉品质情况,试验选取红安格斯牛、西门塔尔牛、夏洛莱牛与郏县红牛的杂交1代公牛各5头,纯种郏县红牛5头,分为试验A组（郏县红牛公牛）、B组（红郏F1代公牛（红安格斯牛×郏县红牛））、C组（西郏F1代公牛（西门塔尔牛×郏县红牛））和D组（夏郏F1代公牛（夏洛莱牛×郏县红牛））4个试验组,在同样的饲养管理条件下,持续育肥3个月后屠宰,利用屠宰测定和检验分析的方法对郏县红牛及其不同杂交品种的体尺发育、肉用性能和肉品质进行分析测定。结果表明：采用红安格斯牛、夏洛莱牛改良郏县红牛,在体高、体斜长、胸围和管围方面与郏县红牛纯种牛相比均无显著性差异（P>0.05）;屠宰测定方面,杂交后代组的头重、皮厚、皮重、前二蹄重和尾重,屠体器官食道、气管、肝脏、脾脏、肺脏、肾脏的重量,以及胴体产肉率、眼肌面积、肉骨比与郏县红牛纯种牛相比均无显著性差异（P>0.05）,但其胴体后腿宽显著高于郏县红牛纯种牛（P<0.05）;红郏F1代公牛高档肉块重和优质肉块重最高,分别为70.22和105.22 kg,但高档牛肉率4组之间差异不显著（P>0.05）,红郏F1代公牛优质牛肉率达到34.43%,显著高于郏县红牛和西郏F1代公牛（P<0.05）,高于夏郏F1代公牛（P>0.05）。在肉品质方面,红郏F1代公牛与肉品风味有关的肌苷酸含量最高,而不饱和脂肪酸含量和与鲜味有关的氨基酸（天门冬氨酸、谷氨酸、甘氨酸和丙氨酸）含量均为夏郏F1代公牛含量最高,分别为53.85%和8.04%。结果提示,采用红安格斯牛、西门塔尔牛和夏洛莱牛改良郏县红牛,没有在体尺发育和肉用性能方面表现出显著优势,但采用红安格斯牛改良郏县红牛可提高郏县红牛肉用性能的潜力,可适度提高高档牛肉和优质牛肉肉块重量,而夏洛莱牛改良郏县红牛可适度提高牛肉品质。     

草原红牛微卫星DNA多态性的研究

为了更好地培育和改良肉用草原红牛，利用草原红牛、夏洛莱牛、西门塔尔牛、利木赞牛、蒙古牛基因组DNA，用8对微卫星引物进行PCR扩增，并将扩增产物置于1．5％琼脂糖电泳进行观察，如有所需的带则转入8％聚丙烯酰胺变性凝胶(PAGE)中电泳分离，绘制指纹图谱。结果表明微卫星标记方法是一种理想的研究方法。