贵州肉牛养殖常用饲草概述

文章对贵州肉牛养殖常用的4种饲草——皇竹草、甜高粱、多花黑麦草、紫花苜蓿进行概述,通过营养成分、饲喂效果、经济效益、产量及种植范围分析比较,提出皇竹草可作为贵州肉牛粗饲料的优先选择并大力推广。     

几种热带牧草饲喂肉牛效果的研究

用四种热带牧草（葛藤、矮象草、皇草、atratum雀稗）饲养肉牛，以评价它们的饲用价值和养牛效果。结果表明：在四种热带牧草中以豆科牧草葛藤最好，它含氮19．63g／kgDM、钙19．2g／kgDM、磷2．5g／kgDM、消化能8．85MJ／kgDM，具有最高的饲养价值，用它作为唯一日粮养牛与其它三种牧草相比可取得最大的增重效果和经济效益；在三种禾本科牧草中，矮象草有较好的养牛效果，它含消化能8．97MJ／kgDM、氮8．13g／kgDM、钙7．2g／kgDM、磷2g／kgDM。总的来看，用生长后期的热带牧草养牛应添加一定量的精料补充料，以促进肉牛增霞。     

主要栽培牧草营养动态及适宜利用时期

以我国北方主要栽培牧草30个品种为材料,用常规分析法、范氏洗涤纤维分析法、酶分析方法测定评价了主要栽培牧草的营养成分及营养价值,分析比较其动态变化,提出了不同牧草适宜利用的生育期.结果表明,豆科牧草的粗蛋白质(CP)含量高于禾本科牧草,总纤维(OCW)含量低于禾本科牧草,低消化性纤维(Ob)含量无明显差异;但豆科牧草随生育期变化不大,而禾本科牧草随生育期变化明显.豆科牧草酸性洗涤纤维(ADF)含量高于禾本科牧草,高消化性纤维(Oa)含量禾本科牧草明显高于豆科牧草,总体上豆科牧草消化率低于禾本科牧草.豆科牧草营养价值大部分呈现随生育期进程阶段性下降的趋势,而禾本科牧草大部分从营养期到开花期表现急速下降.综合分析获得高品质饲草的适宜利用时期,禾本科牧草大部分为营养期,少部分在整个生育期均无大的差异;豆科牧草在营养期,开花期及营养期或成熟期无大的差异.     

Nutrient Composition and Digestibility of Organic Broiler Diets and Pasture Forages

Poultry diets are formulated based on requirements of birds reared without access to pasture. Consumer demand for organic and free-range poultry has resulted in an increase in the use of certified organic feed. Organic poultry may have the opportunity to utilize nutrients found in forage. The addition of exogenous enzymes and manipulation of cecal microbial populations may affect the utilization of forage nutrients. The objectives of this study were as follows: 1) to determine AME_n and TME_n of organic grower diets with or without nonstarch polysaccharide enzyme supplementation and compare these values to a conventional grower diet, 2) to determine AME_n, TME_n, and true amino acid digestibility (TAAD) of forage samples with or without nonstarch polysaccharide enzyme supplementation, and 3) to determine if cecum modification affects forage AME_n, TME_n, and TAAD. The experiment was conducted using cecectomized, intact, and intact grass-fed roosters as models. Enzyme supplementation increased AME_n and TME_n values for organic feeds but not forage. Bird type had no effect on AME_n and TME_n for any treatment. The TAAD of forage was not significantly affected by enzyme supplementation. However, trends in bird type effect were observed for several amino acids.     

太行肉牛育种指数构成分析

对应太行肉牛育种实践,综合分析太行肉牛新品种选育的目标性状以及各性状在总性能指数构成中的权重。太行肉牛新品种选育的总性能指数由体型结构、适应性、生长发育、繁殖力、泌乳力及牛肉指数等六大目标性状构成,权重分别为16%、18%、25%、25%、6%和10%。同时描述了各目标性状的具体度量与数据采集方法。以期业界同仁共同探讨、批评指正,合力推进太行肉牛的育种进程。     

北方肉牛常用粗饲料主要营养成分瘤胃有效降解率

[目的]本文旨在研究北方主要粗饲料用于饲养肉牛的营养价值。[方法]试验采用3×3拉丁方试验设计,用3头装有永久性瘤胃瘘管的西门塔尔杂交肉牛,对稻草、玉米秸和黄贮玉米秸的主要营养成分进行瘤胃有效降解率研究。[结果]显示:①玉米秸和黄贮玉米秸之间比较,除了黄贮玉米秸的NDF有效降解率显著高于玉米秸外(P0.05),二者的DM、CP和ADF有效降解率差异不显著(P0.05),但均以黄贮玉米秸高于玉米秸;②稻草的DM、CP、NDF和ADF有效降解率显著低于玉米秸和玉米秸黄贮(P0.05)。[结论]试验表明玉米秸和黄贮玉米秸对肉牛的营养价值显著优于稻草。玉米秸经过黄贮发酵后,提高了玉米秸NDF的有效降解率。稻草对肉牛的营养价值较低。     

过瘤胃保护脂肪对肉牛增重和营养物质表观消化率的影响

为研究过瘤胃脂肪对肥育肉牛增重和营养物质消化的影响,将87头西杂肉牛分成2组,试验组在对照组的日粮基础上补饲300g过瘤胃脂肪,结果表明:日粮中添加过瘤胃脂肪可显著提高肉牛日增重和饲料转化效率(P<0.05),试验组和对照组的日增重分别为1255g和1113g。过瘤胃脂肪添加对全消化道干物质(DM)、有机物(OM)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)消化率影响不显著(P>0.05),试验组全消化道粗脂肪的表观消化率显著高于对照组(P<0.05),但试验组日粮粗蛋白质消化率显著低于对照组(P<0.05)。     

不同水平赖氨酸对肉牛瘤胃营养物质代谢规律的影响

采用 10月龄鲁西黄牛×利木赞杂交公牛 3只 ,装有瘤胃、十二指肠和回肠瘘管 ,根据基础日粮 待测氨基酸的方法 ,按 6× 3不完全拉丁方设计 ,从瘤胃投饲 6种水平的包被赖氨酸 ,分别为 0、6、9、12、15和 18g/d。试验结果表明 :各组瘤胃液pH值和氨氮的差异不大 ,6个水平组的试验牛的pH值和氨氮在 2 4小时内的变化规律一致。投饲 15g/d的动物油包被赖氨酸 ,日增重、可消化氮、沉积氮、沉积氮 /可消化氮显著高于其他四组 ,分别为 3 61 5 2g/d± 12 2g/d、84 40g/d± 3 3 3g/d、19 0 8g/d± 3 61g/d和 2 0 73 %±3 66%。瘤胃投饲 15g/d的赖氨酸 ,ADF和NDF在瘤胃的含量最低 ,表明牛ADF和NDF在瘤胃的降解率提高 ,但DM含量最大     

2种营养水平下不同遗传基础肉牛对日粮养分消化率的比较研究

The experiment aimed to study the difference on the dietary nutrient digestibility of different genetic basis beef cattle during two nutrient levels.Forty-eight heads of different genetic basis beef cattle （Charolais×Simmental-crossbred cattle,Gelbvieh×Simmental-crossbred cattle,Angus×Simmental-crossbred cattle and Limousin×Simmental-crossbred cattle) were introduced,feeding two different nutritional level of diets,adopting 4×2 two factor design,and carrying on the seven days of digestion experiment using endogeny indicator method.The results showed as follows：①From genetic basis,crude protein digestibility in Gelbvieh×Simmental-crossbred cattle was significantly higher than that in Angus×Simmental-crossbred cattle (P＜0.05),and extremely significantly higher than that in Limousin×Simmental-crossbred cattle（P<0.01）, crude fat digestibility in Gelbvieh×Simmental-crossbred cattle was extremely significantly higher than that in Charolais×Simmental-crossbred cattle and Angus×Simmental-crossbred cattle (P＜0.01).②From nutritional level,the nutrient digestibility of beef cattle in feeding a high nutrition diet were extremely significantly higher than that in feeding a low nutrition diet (P＜0.01).③From the interaction of genetic basis and nutritional level,nutrient digestibility decreased with the increase of nutritional level of diet in Charolais×Simmental-crossbred cattle,Angus×Simmental-crossbred cattle and Limousin×Simmental-crossbred cattle,while Gelbvieh×Simmental-crossbred cattle were on the contrary.The results indicated that genetic basis had significant influences on crude protein digestibility and crude fat digestibility （P＜0.05）,nutritional level of diet had significant influences on the digestibility of dry matter,organic matter,crude protein,crude fiber,crude ash and crude fat （P＜0.05）,crude protein digestibility were influenced significantly by genetic basis and nutritional level of diet at the same time （P＜0.05）.     

Stocking Rate and Fuels Reduction Effects on Beef Cattle Diet Composition and Quality

An experiment was conducted to evaluate the influence of forest fuels reduction on diet quality, botanical composition, relative preference, and foraging efficiency of beef cattle grazing at different stocking rates. A split plot factorial design was used, with whole plots (3 ha) being fuel reduced or no treatment (control), and split plots (1 ha) within whole plots were grazed to three levels of forage utilization; (low) 3 heifers · ha^?1, (moderate) 6 heifers · ha^?1, (high) 9 heifers · ha^?1, with a 48-h grazing duration. Grazing treatments were applied in August of 2005 and 2006. Cattle diet composition and masticate samples were collected during 20-min grazing bouts using six ruminally cannulated cows in each experimental unit. Relative preference indices indicated a strong preference for grass regardless of treatment and stocking rate. Grass consumption was lower in control pastures (P < 0.05) and tended (P < 0.095) to decrease with increased stocking rates. Shrub use was higher in control pastures displaying a quadratic effect (P < 0.05) due to stocking, whereas shrub use increased with stocking rate across all treatments. Cattle grazing control pastures consumed diets higher in crude protein compared to cattle grazing treated pastures (P < 0.05). In vitro dry matter digestibility values were lower (P < 0.05) in control sites and tended (P = 0.10) to decrease with increased stocking rates. In both control and treated pastures, bites per minute and grams consumed per minute declined (P = 0.003) with increased stocking, indicating foraging efficiency of cattle decreases with increased stocking rates. Our data indicated cattle grazing late season grand fir habitat types have a strong preference for grasses regardless of treatment or stocking rate. However, as stocking rate increased in both control and treated pastures, grass consumption decreased, shrub consumption increased, and foraging efficiency decreased.     

半胱胺对肉牛生产性能和养分消化率及血清生化指标的影响

为了研究半胱胺对肉牛生产性能、养分消化率及血清生化指标的影响,试验选择体重350 kg左右西门塔尔牛公牛与本地黄牛母牛杂交的杂交公牛64头,随机分为4组,每组16头,半胱胺的添加量分别为5 g/(头.d)(1组)、10 g/(头.d)(2组)、20 g/(头.d)(3组)、0 g/(头.d)(对照组),试验期63 d。结果表明:(1)试验牛采食正常,各组间采食量无显著差异。添加20 g/(头.d)半胱胺试验组日增重达到1.217 kg。显著高于其他3组(P<0.05),添加5 g/(头.d)半胱胺试验组比对照组略高,添加10 g/(头.d)半胱胺试验组比对照组略低,但均差异不显著(P>0.05)。添加20 g/(头.d)半胱胺试验组的耗料/增重显著低于其他各组(P<0.01),添加5 g/(头.d)半胱胺试验组的耗料/增重显著低于添加10 g/(头.d)半胱胺试验组和对照组(P<0.05),而添加10 g/(头.d)半胱胺试验组的料重比与对照组差异不显著(P>0.05)。(2)添加20 g/(头.d)半胱胺试验组的粗蛋白消化率显著高于对照组(P<0.05),粗脂肪消化率则极显著高于对照组(P<0.01);中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)消化率组间差异不显著(P>0.05)。(3)添加20 g/(头.d)半胱胺试验组的血糖(glucose)水平最高,显著高于其他各组(P<0.05);而添加20 g/(头.d)半胱胺试验组的血清尿素氮(BUN)值最低,显著低于其他各组(P<0.05),生长抑素(SS)值为56.03 pg/mL,极显著低于对照组的71.46 pg/mL(P<0.01);添加20 g/(头.d)半胱胺试验组的血清3-碘甲状腺原氨酸(T3)和甲状腺素(T4)水平均高于对照组(P<0.05),而生长激素(GH)和胰岛素样生长因子(IGF-1)水平也显著高于对照组(P<0.01);试验组的血清胰岛素(INS)水平与对照组差异不显著(P>0.05)。     

肉牛引进过程的操作技术规范

肉牛购进过程中存在的实际问题,可能给养牛企业和养牛户造成极大的损失。本文分别从购进牛只的选购目标、健康状况、饲养方式及疫病监测方面提出具体措施;新购牛在当地先需要一个隔离稳定观察期,并做好运输前各项准备工作;提出在运输环节中,对人员、车辆、消毒、草料及饮水准备,饲喂细节、抗应激处理、装车密度、运输过程中的注意事项等;运到后圈舍消毒、隔离观察、饲喂和饮水的过渡方法,强化免疫接种,等待牛群稳定后才可进入繁育或者育肥环节。     

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。     

贵州肉牛业发展现状及展望

贵州有温和的气候、充沛的雨量、428.7万hm^2（公顷）牧草山地、430万头黄牛,为发展肉牛产业提供了良好的先决条件.目前全省在大面积开展肉牛杂交改良,发展农村养殖小区,肉牛产业已经迈入起步阶段.随着优质肉牛基地县建设项目和省科技攻关重大专项的实施,我省肉牛产业将在5年左右形成一定规模,养殖技术水平将有明显的提高.从而认为,贵州肉牛产业正在进入快速发展阶段.