两种中国外血杂交黄牛的营养代谢及育肥技术的研究
|
摘要
本研究通过两个试验探讨了日粮不同能量,蛋白水平对夏南牛瘤胃发酵,消化代谢,血液指标以及不同性别湘中黑牛的生产性能,胴体指标与肉品质的影响。
试验—研究日粮不同能量蛋白水平对肉牛瘤胃发酵、消化代谢性能及血液指标的影响,选取4头(体重：570±23kg)健康的装有永久瘤胃瘘管的夏南牛(夏洛莱×南阳牛),采用2×2因子,选取两个能量水平(TDN:70%DM,76%DM),两个蛋白水平(DM)(1)11.9%CP、7.7%RDP,(2)14.3%CP、9.4%RDP。试验采用4×4拉丁方设计,分为四个营养水平组：低能量高蛋白(TDN:70%,CP:14.3%、RDP:9.4%);高能量高蛋白(TDN:76%,CP:14.3%、RDP:9.4%);低能量低蛋白(TDN:70%,CP:11.9%、RDP:7.7%);高能量低蛋白(TDN:76%, CP:11.9%、RDP:7.7%).每个试验期为16天,其中预饲期13天,采样期3天。采样期内每天于采食后0,2,4,6,8,10和12小时采集瘤胃液用于测定pH、挥发性脂肪酸(VFA)浓度和氨态氮(NH3-N),连续3天每天全收粪尿进行消化代谢试验测定,试验期最后一天通过颈静脉注射在采食后0,6,12小时后采集血样。
结果表明,在瘤胃发酵方面,不同日粮处理组对瘤胃pH值和总挥发性脂肪酸含量影响差异不显著(P>0.05),但高能量组乙酸浓度低,丙酸浓度高,乙酸／丙酸值小(P<0.05),高蛋白组中瘤胃氨态氮浓度比低蛋白组高(P<0.05),在消化代谢方面,四种日粮配方中,高能量水平日粮的干物质消化率、粗蛋白表观消化率、有机物表观消化率高于低能量水平日粮,差异显著(P<0.05),而NDF与ADF的消化率各组之间差异不显著(P>0.05),随着能量水平的提高,NDF与ADF表观消化率有降低趋势。随着蛋白水平的提高,氮的沉积增加,同时能量水平提高使氮沉积率增加(P<0.05),四种日粮配方对血浆中葡萄糖、总蛋白、甘油三酯的影响差异不显著(P>0.05),蛋白水平对血浆尿素氮影响差异极显著(P<0.01)。
试验二选取47头湘中黑牛(安格斯与湘西黄牛杂交一代：去势公牛23头,母牛24头),分为两个阶段,第一阶段育成期,从6.5月龄开始,所有试验牛在育成期采食同一种饲料,历时184天,然后进入育肥期,该阶段采用2×2×2因子,两个能量水平(TDN:70%、80%DM)、两个蛋白水平(CP:11.9%、14.3%DM)、性别(去势公牛、母牛),分为四个营养水平组,高能量低蛋白(HE,LP),高能量高蛋白(HE,HP),低能量低蛋白(LE,LP),低能量高蛋白(LE,HP)。高能量低蛋白组去势公牛5头,母牛6头,其余三个组平均每组12头牛,去势公牛与母牛各半,饲喂146天后屠宰进行胴体与肉品质测定。
结果表明,肉牛的日增重与最后屠宰体重没有受到日粮能量,蛋白水平及性别的影响。与低能量水平相比,高能量水平在降低动物的采食量(DMI,6.76vs7.48kg DM/d,的同时促进了试验牛胸围的增长(46.1vs36.8cm, P<0.01),胴体脂肪(19.9vs16.3%,P<0.05),肌间脂肪的沉积(29.9vs22.8%DM,P<0.01),提高了高档优质肉块出肉率(39.9vs36.5%,P<0.05)。高蛋白水平则促进了屠宰率的增加(53.4vs54.9%,P<0.05)。母牛的休长增量小于公牛(9.0vs8.3cm,P<0.01),但胴体脂肪高于去势公牛(16.8%vs19.4%,P<0.05)。肉质特性包括剪切力(3.14kg)、滴水损失(2.5%)、蒸煮损失(31.5%)、系水力(52.9%)以及脂肪酸、氨基酸等营养风味物质未受能量、蛋白水平和性别这三个因素的影响。
试验结果表明对于夏南牛来说,高能量高蛋白日粮能促进日粮中其他营养物质的吸收,增加氮沉积并且没有对肉牛的正常消化代谢产生不良影响。对于湘中黑牛来说高能量水平日粮提高了脂肪在胴体及西冷中的比例,高蛋白水平日粮增加了肉牛的屠宰率。去势公牛沉积胴体脂肪能力低于母牛。
The experiment was carried out to evaluate the rumen fermentation^nutrients apparent digestibility> blood biochemical constituents, growth performance, carcass characteristics and meat quality of Chinese peripheral blood hybridization yellow cattle based on variations in nutrition levels and sex.
In experiment one, the research was carried out to evaluate the effects of two dietary energy levels (TDN:70%,76%DM) and two protein levels (1)11.9%CP,7.7%RDP,(2)14.3%CP,9.4%RDP on rumen fermentation, nutrients apparent digestibility, blood biochemical constituents of Chinese crossbred yellow cattle. Four ruminally fistulated Charolais×Nan yang yellow bulls, about570±23kg live weight, were randomly assigned according to a2×2factorial arrangement in a4×4latin square design to receive four dietary treatments. The treatments were as follows:low energy and high protein LEHP(TDN:70%,CP:14.3%, RDP:9.4%), high energy and high protein HEHP (TDN:76%, CP:14.3%, RDP:9.4%), low energy and low protein LELP (TDN:70%, CP:11.9%, RDP:7.7%), high energy and low protein (TDN:76%, CP:11.9%, RDP:7.7%). Each experimental period consisted of16d which provided13d for dietary treatments adaption and3d for sample collection. During the sample collection period, ruminal contents were sampled at0,2,4,6,8,10and12h after feeding to determine ruminal pH, the concentrations of VFA, and ammonia N, Urine and fecal were total collected each day, blood samples was collected from the jugular vein into tubes containing12mg of EDTA at0,6,12h after the morning feeding on the final day.
The result revealed that ruminal pH and total volatile fatty acids (VFA) were not affected in all treatments. Acetate concentration was lower and propionate concentration was greater (P<0.01) for bulls fed HE compared with the LE diet. Higher ammonia nitrogen (NH3-N) concentration was in bulls fed HP diet as compared to bulls fed LP diet (P<0.01). Total apparent digestibility of dry matter (DM), crude protein (CP), organic matter (OM) and N utilization were greater for bulls fed HE vs LE diet (P<0.05), but digestibility of neutral detergent fiber (NDF) and acid detergent fiber (ADF) were not influenced by the dietary treatments(P>0.05). Bulls fed HP diet had increased N retention than LP diet (P<0.05). The total protein, glucose, triglyceride concentration of blood plasma were similar among all dietary treatments(P>0.05).Plasma urea nitrogen(PUN) was greater in HP dietary treatment (P<0.05)
In experiment two, the research was carried out to evaluate the growth performance, carcass characteristics and meat quality of FI Angus×Chinese Xiangxi yellow cattle based on variations in nutrition ievels and sex. Forty-seven Xiangzhong black cattle (Fi Angus×Chinese Xiangxi yeiiow cattle were selected, steers, n=23; heifers, n=24) and fed the same ration during the backgrounding period for i84days. The animais were put in a2×2×2factorial arrangement to determine the effects of2 levels of dietary energy (TDN:70%,80%DM) and protein(CP:11.9%,14.3%DM) and sex(S:male, female) during the finishing phase for146days until slaughter. The treatments were as follows (1) high energy and low protein (HELP; TDN:80%DM, CP:11.9%DM),(2) high energy and high protein (HEHP; TDN:80%DM, CP:14.3%DM),(3) low energy and low protein (LELP;TDN:70%DM, CP:11.9%DM) and (4) low energy and high protein (LEHP; TDN:70%DM, CP:14.3%DM). Six steers and six heifers were located in each treatment, excluding HELP, which contained five steers and six heifers.
The result revealed that the growth rate and final carcass weight were not affected by the dietary energy and protein levels or sex. Compared with cattle fed an LE diet, cattle fed an HE diet had lower dry matter intake (DMI,6.76vs7.48kg DM/d, P<0.01), greater chest girth increments (46.1vs36.8cm, P<0.01), and higher carcass fat (19.9vs16.3%, P<0.05) and intramuscular fat content (29.9vs22.8%DM, P<0.01); in addition, the cattle fed an HE diet had improved top and medium top grade commercial meat cut yield (39.9vs36.5%, P<0.05). The dressing percentage was higher for cattle fed an HP diet than an LP diet.(53.4vs54.9%,P<0.05). Steers had a greater length increment (9.0vs8.3cm, P<0.01). but lower carcass fat content (16.8%vs19.4%) than heifers. The meat quality traits including shear force value, drip loss, cooking loss and water holding capacity were not different among treatments or sex and averaged3.14kg,2.5%,31.5%and52.9%, respectively, and the nutritive profiles (both fatty and amino acid composition) were not influenced by the energy or protein levels or sex.
Results from the two trails indicated that energy level played an important role on dietary nutrients assimilation. Higher dietary energy and protein concentrations minimize N excretion without having negative effect on animal health for Charolaisx Nan yang yellow bulls. And for Angus x Chinese Xiangxi yellow cattle(Fl), high energy level of the diet increased the fat composition of the carcass and iongissimus muscle between the i2th and13th ribs.High protein ievel of the diet increased the dressing percentage. Steers had less fat deposition ability than heifers.
试验—研究日粮不同能量蛋白水平对肉牛瘤胃发酵、消化代谢性能及血液指标的影响,选取4头(体重：570±23kg)健康的装有永久瘤胃瘘管的夏南牛(夏洛莱×南阳牛),采用2×2因子,选取两个能量水平(TDN:70%DM,76%DM),两个蛋白水平(DM)(1)11.9%CP、7.7%RDP,(2)14.3%CP、9.4%RDP。试验采用4×4拉丁方设计,分为四个营养水平组：低能量高蛋白(TDN:70%,CP:14.3%、RDP:9.4%);高能量高蛋白(TDN:76%,CP:14.3%、RDP:9.4%);低能量低蛋白(TDN:70%,CP:11.9%、RDP:7.7%);高能量低蛋白(TDN:76%, CP:11.9%、RDP:7.7%).每个试验期为16天,其中预饲期13天,采样期3天。采样期内每天于采食后0,2,4,6,8,10和12小时采集瘤胃液用于测定pH、挥发性脂肪酸(VFA)浓度和氨态氮(NH3-N),连续3天每天全收粪尿进行消化代谢试验测定,试验期最后一天通过颈静脉注射在采食后0,6,12小时后采集血样。
结果表明,在瘤胃发酵方面,不同日粮处理组对瘤胃pH值和总挥发性脂肪酸含量影响差异不显著(P>0.05),但高能量组乙酸浓度低,丙酸浓度高,乙酸／丙酸值小(P<0.05),高蛋白组中瘤胃氨态氮浓度比低蛋白组高(P<0.05),在消化代谢方面,四种日粮配方中,高能量水平日粮的干物质消化率、粗蛋白表观消化率、有机物表观消化率高于低能量水平日粮,差异显著(P<0.05),而NDF与ADF的消化率各组之间差异不显著(P>0.05),随着能量水平的提高,NDF与ADF表观消化率有降低趋势。随着蛋白水平的提高,氮的沉积增加,同时能量水平提高使氮沉积率增加(P<0.05),四种日粮配方对血浆中葡萄糖、总蛋白、甘油三酯的影响差异不显著(P>0.05),蛋白水平对血浆尿素氮影响差异极显著(P<0.01)。
试验二选取47头湘中黑牛(安格斯与湘西黄牛杂交一代：去势公牛23头,母牛24头),分为两个阶段,第一阶段育成期,从6.5月龄开始,所有试验牛在育成期采食同一种饲料,历时184天,然后进入育肥期,该阶段采用2×2×2因子,两个能量水平(TDN:70%、80%DM)、两个蛋白水平(CP:11.9%、14.3%DM)、性别(去势公牛、母牛),分为四个营养水平组,高能量低蛋白(HE,LP),高能量高蛋白(HE,HP),低能量低蛋白(LE,LP),低能量高蛋白(LE,HP)。高能量低蛋白组去势公牛5头,母牛6头,其余三个组平均每组12头牛,去势公牛与母牛各半,饲喂146天后屠宰进行胴体与肉品质测定。
结果表明,肉牛的日增重与最后屠宰体重没有受到日粮能量,蛋白水平及性别的影响。与低能量水平相比,高能量水平在降低动物的采食量(DMI,6.76vs7.48kg DM/d,的同时促进了试验牛胸围的增长(46.1vs36.8cm, P<0.01),胴体脂肪(19.9vs16.3%,P<0.05),肌间脂肪的沉积(29.9vs22.8%DM,P<0.01),提高了高档优质肉块出肉率(39.9vs36.5%,P<0.05)。高蛋白水平则促进了屠宰率的增加(53.4vs54.9%,P<0.05)。母牛的休长增量小于公牛(9.0vs8.3cm,P<0.01),但胴体脂肪高于去势公牛(16.8%vs19.4%,P<0.05)。肉质特性包括剪切力(3.14kg)、滴水损失(2.5%)、蒸煮损失(31.5%)、系水力(52.9%)以及脂肪酸、氨基酸等营养风味物质未受能量、蛋白水平和性别这三个因素的影响。
试验结果表明对于夏南牛来说,高能量高蛋白日粮能促进日粮中其他营养物质的吸收,增加氮沉积并且没有对肉牛的正常消化代谢产生不良影响。对于湘中黑牛来说高能量水平日粮提高了脂肪在胴体及西冷中的比例,高蛋白水平日粮增加了肉牛的屠宰率。去势公牛沉积胴体脂肪能力低于母牛。
The experiment was carried out to evaluate the rumen fermentation^nutrients apparent digestibility> blood biochemical constituents, growth performance, carcass characteristics and meat quality of Chinese peripheral blood hybridization yellow cattle based on variations in nutrition levels and sex.
In experiment one, the research was carried out to evaluate the effects of two dietary energy levels (TDN:70%,76%DM) and two protein levels (1)11.9%CP,7.7%RDP,(2)14.3%CP,9.4%RDP on rumen fermentation, nutrients apparent digestibility, blood biochemical constituents of Chinese crossbred yellow cattle. Four ruminally fistulated Charolais×Nan yang yellow bulls, about570±23kg live weight, were randomly assigned according to a2×2factorial arrangement in a4×4latin square design to receive four dietary treatments. The treatments were as follows:low energy and high protein LEHP(TDN:70%,CP:14.3%, RDP:9.4%), high energy and high protein HEHP (TDN:76%, CP:14.3%, RDP:9.4%), low energy and low protein LELP (TDN:70%, CP:11.9%, RDP:7.7%), high energy and low protein (TDN:76%, CP:11.9%, RDP:7.7%). Each experimental period consisted of16d which provided13d for dietary treatments adaption and3d for sample collection. During the sample collection period, ruminal contents were sampled at0,2,4,6,8,10and12h after feeding to determine ruminal pH, the concentrations of VFA, and ammonia N, Urine and fecal were total collected each day, blood samples was collected from the jugular vein into tubes containing12mg of EDTA at0,6,12h after the morning feeding on the final day.
The result revealed that ruminal pH and total volatile fatty acids (VFA) were not affected in all treatments. Acetate concentration was lower and propionate concentration was greater (P<0.01) for bulls fed HE compared with the LE diet. Higher ammonia nitrogen (NH3-N) concentration was in bulls fed HP diet as compared to bulls fed LP diet (P<0.01). Total apparent digestibility of dry matter (DM), crude protein (CP), organic matter (OM) and N utilization were greater for bulls fed HE vs LE diet (P<0.05), but digestibility of neutral detergent fiber (NDF) and acid detergent fiber (ADF) were not influenced by the dietary treatments(P>0.05). Bulls fed HP diet had increased N retention than LP diet (P<0.05). The total protein, glucose, triglyceride concentration of blood plasma were similar among all dietary treatments(P>0.05).Plasma urea nitrogen(PUN) was greater in HP dietary treatment (P<0.05)
In experiment two, the research was carried out to evaluate the growth performance, carcass characteristics and meat quality of FI Angus×Chinese Xiangxi yellow cattle based on variations in nutrition ievels and sex. Forty-seven Xiangzhong black cattle (Fi Angus×Chinese Xiangxi yeiiow cattle were selected, steers, n=23; heifers, n=24) and fed the same ration during the backgrounding period for i84days. The animais were put in a2×2×2factorial arrangement to determine the effects of2 levels of dietary energy (TDN:70%,80%DM) and protein(CP:11.9%,14.3%DM) and sex(S:male, female) during the finishing phase for146days until slaughter. The treatments were as follows (1) high energy and low protein (HELP; TDN:80%DM, CP:11.9%DM),(2) high energy and high protein (HEHP; TDN:80%DM, CP:14.3%DM),(3) low energy and low protein (LELP;TDN:70%DM, CP:11.9%DM) and (4) low energy and high protein (LEHP; TDN:70%DM, CP:14.3%DM). Six steers and six heifers were located in each treatment, excluding HELP, which contained five steers and six heifers.
The result revealed that the growth rate and final carcass weight were not affected by the dietary energy and protein levels or sex. Compared with cattle fed an LE diet, cattle fed an HE diet had lower dry matter intake (DMI,6.76vs7.48kg DM/d, P<0.01), greater chest girth increments (46.1vs36.8cm, P<0.01), and higher carcass fat (19.9vs16.3%, P<0.05) and intramuscular fat content (29.9vs22.8%DM, P<0.01); in addition, the cattle fed an HE diet had improved top and medium top grade commercial meat cut yield (39.9vs36.5%, P<0.05). The dressing percentage was higher for cattle fed an HP diet than an LP diet.(53.4vs54.9%,P<0.05). Steers had a greater length increment (9.0vs8.3cm, P<0.01). but lower carcass fat content (16.8%vs19.4%) than heifers. The meat quality traits including shear force value, drip loss, cooking loss and water holding capacity were not different among treatments or sex and averaged3.14kg,2.5%,31.5%and52.9%, respectively, and the nutritive profiles (both fatty and amino acid composition) were not influenced by the energy or protein levels or sex.
Results from the two trails indicated that energy level played an important role on dietary nutrients assimilation. Higher dietary energy and protein concentrations minimize N excretion without having negative effect on animal health for Charolaisx Nan yang yellow bulls. And for Angus x Chinese Xiangxi yellow cattle(Fl), high energy level of the diet increased the fat composition of the carcass and iongissimus muscle between the i2th and13th ribs.High protein ievel of the diet increased the dressing percentage. Steers had less fat deposition ability than heifers.
引文
[1].曹兵海苏：南方肉牛产业现状与发展战略之我见.中国畜牧业2012,20：18-28.
[2].蒋洪茂：阉牛育肥的优缺点.科学种养2010,12：34.
[3]. Lazzaroni C and D Biagini:Effect of pre-and post-pubertal castration on Piemontese male cattle. II: Carcass measures and meat yield. Meat Science 2008,80:442-448.
[41. Morgan JB, TL Wheeler, M Koohmaraie, JD Crouse, and JW Savell:Effect of castration on myofibrillar protein turnover, endogenous proteinase activities, and muscle growth in bovine skeletal muscle. Journal of Animal Science 1993,71:408-414.
[51. Segato S, C Elia, C Mazzini, C Bianchi, and I Andrighetto:Effect of castration age on carcass traits and meat quality of Simmental bulls. Italian Journal of Animal Science 2010,4.
[6]. Champagne J, J Carpenter, J Hentges, A Palmer, and M Koger:Feedlot performance and carcass characteristics of young bulls and steers castrated at four ages. Journal of Animal Science 1969,29: 887-890.
[71. Worrell M, D Clanton, and CR Calkins:Effect of weight at castration on steer performance in the feedlot. Faculty Papers and Publications in Animal Science 1987:567.
[8]. Micol D, MP Oury, B Picard, JF Hocquette, M Briand, R Dumont, D Egal, R Jailler, H Dubroeucq, and J Agabriel:Effect of age at castration on animal performance, muscle characteristics and meat quality traits in 26-month-old Charolais steers. Livestock Science 2009,120:116-126.
[9].王景才,刘树军,吴爱芹等：全株玉米青贮料喂育肥牛的试验.黄牛杂志2003,29：27--28.
[10].蒋洪茂：我国黄牛生产特级(高档)牛肉的主要技术措施.科学种养2011,02：33--35.
[11]. Yang A, MJ Brewster, MC Lanari, and RK Tume:Effeet of vitamin E supplementation on a-tocopherol and P-carotene concentrations in tissues from pasture-and grain-fed cattle. Meat Science 2002,60:35-40.
[12]. Daly C, O Young, A Graafhuis, S Moorhead, and H Easton:Some effects of diet on beef meat and fat attributes. New Zealand Journal of Agricultural Research 1999,42:279-287.
[13]. Dunne PG, FJ Monahan, FP O'Mara, and AP Moloney:Colour of bovine subcutaneous adipose tissue:A review of contributory factors, associations with carcass and meat quality and its potential utility in authentication of dietary history. Meat Science 2009,81:28-45.
[14]. Pethick DW, BL Mclntyre, G Tudor, and JB Rowe:The partitioning of fat in ruminants:can nutrition be used as a tool to regulate marbling? Recent Advances in Animal Nutrition in Australia 1997,11: 151-158.
[15].薛华：肉牛常用饲料的特点.乡村科技2011,4：29.
[16]. Galyean M:Protein levels in beef cattle finishing diets:industry application, university research, and systems results. Journal of Animal Science 1996,74:2860-2870.
[171. Mitsumoto M, S Ozawa, T Mitsuhashi, and K Koide:Effect of dietary vitamin E supplementation for one week before slaughter on drip, colour and lipid stability during display in Japanese Black steer beef. Meat Science 1998,49:165-174.
[18]. Arnold R, K Scheller, S Arp, S Williams, D Buege, and D SchaeferEffect of long-or short-term feeding of alpha-tocopheryl acetate to Holstein and crossbred beef steers on performance, carcass characteristics, and beef color stability. Journal of Animal Science 1992,70:3055-3065.
[19].曹兵海,陈幼春,许尚忠等：我国的肉牛育肥技术模式与牛肉市场层次.中国畜牧杂志2007,43：55--58.
[20].沈迪非,江华：“入世”对我国国产牛肉市场的影响和对策.国际贸易问题2000,9：4-6.
[21]. Brown MS, CH Ponce, and R Pulikanti:Adaptation of beef cattle to high-concentrate diets: performance and ruminal metabolism. Journal of Animal Science 2006,84 Suppl:E25-33.
[22]. Odle J and DM Schaefer:Influence of rumen ammonia concentration on the rumen degradation rates of barley and maize. Br J Nutr 1987,57:127-38.
[23]. Satter LD and LL Slyter:Effect of ammonia concentration of rumen microbial protein production in vitro. British Journal of Nutrition 1974,32:199-208.
[24]. Steinfeld H and T Wassenaar:The role of livestock production in carbonand nitrogen cycles. Annu. Rev. Environ. Resour.2007,32:271-294.
[25]. Schroeder GF and EC Titgemeyer:Interaction between protein and energy supply on protein utilization in growing cattle:A review. Livestock Science 2008,114:1-10.
[26]. Brown MS, CR Krehbiel, ML Galyean, MD Remmenga, JP Peters, B Hibbard, J Robinson, and WM Moseley:Evaluation of models of acute and subacute acidosis on dry matter intake, ruminal fermentation, blood chemistry, and endocrine profiles of beef steers. Journal of Animal Science 2000,78:3155-68.
[27]. Bevans DW, KA Beauchemin, KS Schwartzkopf-Genswein, JJ McKinnon, and TA McAllister:Effect of rapid or gradual grain adaptation on subacute acidosis and feed intake by feedlot cattle. Journal of Animal Science 2005,83:1116-32.
[28].万发春,吴乃科,宋增福,杨在宾：不同能量水平对肉牛瘤胃代谢的影响研究.山东农业大学学报(自然科学版)2003,34：54-58.
[29]. Larick DK, HB Hedriek, ME Bailey, JE Williams, DL Hancock, and GB Garner:Flavor constituents of beef as influenced by forage-and grain-feeding. Journal of Food Science 1987,52:245-251.
[30]. Medeiros LC, RA Field, DJ Menkhaus, and WC Russell:Evaluation of range-grazed and concentraie-fed beef by a trained sensory panel, a household panel and a laboratory lest market group. Journal of Sensory Studies 1987,2:250-272.
[31]. Richardson JM, RG Wilkinson, and LA Sinclair:Synchrony of nutrient supply to the rumen and dietary energy source and their effects on the growth and metabolism of lambs. J.Anim. Sci 2003, 81:1332-1347.
[32]. Bach A, S Calsamiglia, and MD Stern:Nitrogen metabolism in the rumen. Journal of Dairy Science 2005,88:E9-E21.
[33]. Rode LM, DC Weakley, and LD Satter Effect of forage amount and particle size in diets of lactating dairy cows on site of digestion and microbial protein synthesis. J.Anim.Sci 1985 65:101-111.
[34]. Sarwar M, JL Firkins, and ML Eastridge:Effects of Varying Forage and Concentrate Carbohydrates on Nutrient Digestibilities and Milk Production by Dairy Cows. J.Dairy Sci 1992,66:811-820.
[35]. Wheeler WE and CH Noller:Effect of forage-to-concentrate ratio in complete feeds and feed intake on digestion of starch by dairy cows. J Dairy Sci 1975,58:1902-6.
[36]. Alhadhrami GJ and JT Hube:Effects of Alfalfa Hay of Varying Fiber Fed at 35 or 50% of Diet on Lactation and Nutrient Utilization by Dairy Cows. J. Dairy Sci 1992,75:3091-3099.
[37]. AOAC:Official methods of analysis,17th Edition. Association of Official Analytical Chemistry, Arlington, Virginia, USA.2000.
[38]. Van Soest PJ, JB Robertson, and BA Lewis:Methods for Dietary Fiber, Neutral Detergent Fiber, and Nonstarch Polysaccharides in Relation to Animal Nutrition. J Dairy Sci 1991,74:3583-3597.
[39]. Broderick GA and JH Kang:Automated simultaneous determination of ammonia and total amino acids in ruminal fluid and in vitro media. Journal of Dairy Science 1980,63:64-75.
[40]. Kim E, K-S Min, C-H Kim, Y Moon, S Kim, and S Lee:The effect of plant extracts on in-vitro ruminal fermentation, methanogenesis and methane-related microbes in the rumen. Asian Australas. J. Anim. Sci 2013,26:517-522.
[41]. Hoover WH and SR Stokes:Balancing carbohydrates and proteins for optimum rumen microbial yield. Journal of Dairy Science 1991,74:3630-44.
[42]. Van Houtert MFJ:The production and metabolism of volatile fatty acids by ruminants fed roughages:A review.. Anim Feed Sci Technol 1993,43:189-225.
[43]. NRC:Nutrient Requirements of Dairy Cattle.7th rev.ed. National Academy Press,Washington,DC. 2001.
[44]. Britton R and R Stock:Acidosis:A continual problem in cattle fed high grain diets. Cornell Nutr.Conf. Feed Manuf, Cornell Univ., Ithaca, NY.1989:8-15.
[45]. Owens FN, DS Secrist, WJ Hill, and DR Gill:Acidosis in cattle:A review. J. Anim. Sci.1998,76: 275-286.
[46]. Krause KM and GR Oetzel:Understanding and preventing subacute ruminal acidosis in dairy herds: A review. Anim. Feed Sci. Technol 2006,126:215-236.
[47]. Nagaraja TG and EC Titgemeyer:Ruminal acidosis in beef cattle:the current microbiological and nutritional outlook. Journal of Dairy Science 2007,90 Suppl 1:E17-38.
[48]. Yang WZ and KA Beauchemin:Increasing physically effective fiber content of dairy cow diets through forage proportion versus forage chop length:chewing and ruminal pH. J Dairy Sci 2009,92: 1603-15.
[49]. Yang WZ and KA Beauchemin:Altering physically effective fiber intake through forage proportion and particle length:digestion and milk production. J Dairy Sci 2007,90:3410-21.
[50]. Couderc JJ, DH Rearte, GF Schroeder, JI Ronchi, and FJ Santini:Silage chop length and hay supplementation on milk yield, chewing activity, and ruminal digestion by dairy cows. J Dairy Sci 2006,89:3599-608.
[51]. Preston H and D Leng:Matching ruminant production systems with available resources in the tropics and sub-tropics. Penambul Books 1987.
[52]. Clark JH, TH Klusmeyer, and MR Cameron:Microbial protein synthesis and flows of nitrogen fractions to the duodenum of dairy cows. Journal of Dairy Science 1992,75:2304-23.
[53]. Yang WZ, KA Beauchemin, and LM Rode:Effects of grain processing, forage to concentrate ratio, and forage particle size on rumen pH and digestion by dairy cows. Journal of Daily Science 2001, 84:2203-16.
[54]. Keady TWJ and CS Mayne:The effect of concentrate energy source on feed intake and rumen fermentation parameters of dairy cows offered a range of grass silages. Animal Feed Science and Technology 2001,90:117-129.
[55]. Murphy M, M Akerlind, and K Holtenius:Rumen fermentation in lactating cows selected for milk fat content fed two forage to concentrate ratios with hay or silage. J Dairy Sci 2000,83:756-64.
[56]. Nocek JE and S Tamminga:Site of digestion of starch in the gastrointestinal tract of dairy cows and its effect on milk yield and composition. J Dairy Sci 1991,74:3598-629.
[57]. Khorasani GR, EK Okine, and JJ Kennelly:Effects of forage source and amount of concentrate on rumen and intestinal digestion of nutrients in late-lactation cows. J Dairy Sci 2001,84:1156-65.
[58]. Dado RG and MS Allen:Intake limitations, feeding behavior, and rumen function of cows challenged with rumen fill from dietary fiber or inert bulk. J Dairy Sci 1995,78:118-33.
[59]. Andrae JG, CW Hunt, SK Duckett, LR Kennington, P Feng, FN Owens, and S Soderlund:Effect of high-oil corn on growth performance, diet digestibility, and energy content of finishing diets fed to beef cattle. J Anim Sci 2000,78:2257-62.
[60]. Pina DS, SC Valadares Filho, LO Tedeschi, AM Barbosa, and RF Valadares:Influence of different levels of concentrate and ruminally undegraded protein on digestive variables in beef heifers. J Anim Sci 2009,87:1058-67.
[61]. MacGregor CA, MR Stokes, WH Hoover, HA Leonard, LL Junkins, Jr., CJ Sniffen, and RW Mailman:Effect of dietary concentration of total nonstructural carbohydrate on energy and nitrogen metabolism and milk production of dairy cows. J Dairy Sci 1983,66:39-50.
[62]. Qiao GH, T Shao, CQ Yu, XL Wang, X Yang, XQ Zhu, and Y Lu:A comparative study at two different altitudes with two dietary nutrition levels on rumen fermentation and energy metabolism in Chinese Holstein cows. J Anim Physiol Anim Nutr (Berl) 2012.
[631. Voelker JA, GM Burato, and MS Allen:Effects of pretrial milk yield on responses of feed intake, digestion, and production to dietary forage concentration. J Dairy Sci 2002,85:2650-61.
[64]. Mabjeesh SJ, A Arieli, I Bruckental, S Zamwell, and H Tagari:Effect of ruminal degradability of crude protein and nonstructural carbohydrates on the efficiency of bacterial crude protein synthesis and amino acid flow to the abomasum of dairy cows. J Dairy Sci 1997,80:2939-49.
[65]. Khalili H and P Huhtanen:Sucrose supplements in cattle given grass silage-based diet.2. Digestion of cell wall carbohydrates. Animal Feed Science and Technology 1991,33:263-273.
[66]. Brown WF and DD Johnson:Effects of energy and protein supplementation of ammoniated tropical grass hay on the growth and carcass characteristics of cull cows. J Anim Sci 1991,69:348-57.
[67]. Russell JB and DB Dombrowski:Effect of pH on the efficiency of growth by pure cultures of rumen bacteria in continuous culture. Appl Environ Microbiol 1980,39:604-10.
[68]. Mould FL, ER 0rskov, and SO Mann:Associative effects of mixed feeds. I. effects of type and level of supplementation and the influence of the rumen fluid pH on cellulolysis in vivo and dry matter digestion of various roughages. Animal Feed Science and Technology 1983,10:15-30.
[69]. Erdman RA:Dietary buffering requirements of the lactating dairy cow:a review. Journal of Dairy Science 1988,71:3246-3266.
[70]. Orskov ER and FDB Hovell:Rumen digestion of hay (measured with dacron bags) by cattle given sugar cane or pangola hay. Tropical Anim. Production 1978,3.9-11.
[71]. Faix S, L Leng, M Szanyiova, and K Boda:Effect of dietary energy intake on tubular reabsorption of urea in sheep. Physiologia Bohemoslovaca 1988.37:493-501.
[72]. Mathis CP, RC Cochran, GL Stokka, JS Heldt, BC Woods, and KC Olson:Impacts of increasing amounts of supplemental soybean meal on intake and digestion by beef steers and performance by beef cows consuming low-quality tallgrass-prairie forage. J Anim Sci 1999,77:3156-62.
[73]. Koster HH, RC Cochran, EC Titgemeyer, ES Vanzant, I Abdelgadir, and G St-Jean:Effect of increasing degradable intake protein on intake and digestion of low-quality, tallgrass-prairie forage by beef cows. Journal of Animal Science 1996,74:2473-81.
[74]. Fike GD, DD Simms, RC Cochran, ES Vanzant, GL Kuhl, and RT Brandt, Jr.:Protein supplementation of ammoniated wheat straw:effect on performance and forage utilization of beef cattle. J Anim Sci 1995,73:1595-601.
[75]. Giraldez FJ, C Valuesb, R Pelaezb, P Frutosa, and AR Mantecona:The influence of digestible organic matter and nitrogen intake on faecal and urinary nitrogen losses in sheep. Livestock Prod.Sci 1997,51:183-190.
[76]. Kokkonen T, AT Tesfa, M Tuori, S Yrjanen, and L Syrjala-Qvist:Effect of concentrate crude protein level on grass silage intake, milk yield and nutrient utilisation by dairy cows in early lactation. Archives of Animal Nutrition 2002,56:213-27.
[77]. Broderick GA:Effects of varying dietary protein and energy levels on the production of lactating dairy cows. Journal of Dairy Science 2003,86:1370-81.
[78]. Haddad SG and MQ Husein:Nutritive value of lentil and vetch straws as compared with alfalfa hay and wheat straw for replacement ewe lambs. Small Rumin Res 2001,40:255-260.
[79]. Hof G, MD Vervoorn, PJ Lenaers, and S Tamminga:Milk urea nitrogen as a tool to monitor the protein nutrition of dairy cows. Journal of Dairy Science 1997,80:3333-3340.
[80]. Broderick GA and MK Clayton:A statistical evaluation of animal and nutritional factors influencing concentrations of milk urea nitrogen. J Dairy Sci 1997,80:2964-71.
[81]. Baker LD, JD Ferguson, and W Chalupa:Responses in urea and true protein of milk to different protein feeding schemes for dairy cows. J.Dairy Sci 1995,78:2424-2434.
[82]. Whitelaw FG, JS Milne, and XB Chen:The effect of a rumen microbial fermentation on urea and nitrogen metabolism of sheep nourished by intragastric infusion. Experimental Physiology 1991,76: 91-101.
[83]. Cuvelier C, JF Cabaraux, I Dufrasne, A Clinquart, JF Hocquette. L Istasse, and JL Hornick:Performance, slaughter characteristics and meat quality of young bulls from Belgian Blue, Limousin and Aberdeen Angus breeds fattened with a sugar-beet pulp or a cereal-based diet. Animal Science 2007,82:125-132.
[84]. Faucitano L, R Berthiaume, M D'Amours, D Pellerin, and DR Ouellet:Effects of corn grain particle size and treated soybean meal on carcass and meat quality characteristics of beef steers finished on a corn silage diet. Meat Science 2011,88:750-754.
[85]. Ludden PA, O Kucuk, DC Rule, and BW Hess:Growth and carcass fatty acid composition of beef steers fed soybean oil for increasing duration before slaughter. Meat Science 2009,82:185-192.
[86]. Warren HE, ND Scollan, M Enser, SI Hughes, RI Richardson, and JD Wood:Effects of breed and a concentrate or grass silage diet on beef quality in cattle of 3 ages. I:Animal performance, carcass quality and muscle fatty acid composition. Meat Science 2008,78:256-269.
[87]. Wu G, PK Davis, NE Flynn, DA Knabe, and JT Davidson:Endogenous synthesis of arginine plays an important role in maintaining arginine homeostasis in postweaning growing pigs. Journal of Nutrition 1997.127:2342-2349.
[88]. Grovum WL:Mechanisms explaining the effects of short chain fatty acids on feed intake in ruminants-osmotic pressure, insulin and glucagon. Ruminant physiology:digestion, metabolism, growth and reproduction. Proceedings 8th International Symposium on Ruminant Physiology.1995: 173-197.
[89]. Klosterman EW:Beef cattle size for maximum efficiency. Journal of Animal Science 1972,34: 875-880.
[90]. Ouyang SJ:Livestock and poultry breeds of Hunan Province. Hunan Science and Technology Press,Changsha.1984:54-60.
[91]. Felius M:Cattle breeds-an encyclopedia. Doetinchem, Netherlands 1995.
[92]. Paschal J, J Sanders, J Kerr, D Lunt, and A Herring:Postweaning and feedlot growth and carcass characteristics of Angus-, gray Brahman-, Gir-, Indu-Brazil-, Nellore-, and red Brahman-sired F1 calves. Journal of Animal Science 1995,73:373-380.
[93]. Alberti P, B Panea, C Sanudo, JL Olleta, G Ripoll, P Ertbjerg, M Christensen, S Gigli, S Failla, S Concetti, JF Hocquette, R Jailler, S Rudel, G Renand, GR Nute, R1 Richardson, and JL Williams:Live weight, body size and carcass characteristics of young bulls of fifteen European breeds. Livestock Science 2008,114:19-30.
[94]. Laborde FL, 1B Mandell, JJ Tosh, JW Wilton, and JG Buchanan-Smith:Breed effects on growth performance, carcass characteristics, fatty acid composition, and palatability attributes in finishing steers. Journal of Animal Science 2001,79:355-365.
[95]. Zhou GH, L Liu, XL Xiu, HM Jian, LZ Wang, BZ Sun, and BS Tong:Productivity and carcass characteristics of pure and crossbred Chinese Yellow Cattle. Meat Science 2001,58:359-362.
[96]. Lunstra DD and SE Echternkamp:Puberty in beef bulls:acrosome morphology and semen quality in bulls of different breeds. Journal of Animal Science 1982,55:638.
[97]. Henricks DM, TC Jenkins, JR Ward, CS Krishnan, and L Grimes:Endocrine responses and body composition changes during feed restriction and realimentation in young bulls. Journal of Animal Science 1994,72:2289-2297.
[98]. Arthur P, J Archer, D Johnston, R Herd, E Richardson, and P Parnell:Genetic and phenotypic variance and covariance components for feed intake, feed efficiency, and other postweaning traits in Angus cattle. Journal of Animal Science 2001,79:2805-2811.
[99]. Urick JJ, MD MacNEIL, and WL Reynolds:Biological type effects on postweaning growth, feed efficiency and carcass characteristics of steers. Journal of Animal Science 1991,69:490-497.
[100]. Dinh TTN, JR Blanton, DG Riley, CC Chase, SW Coleman, WA Phillips, JC Brooks, MF Miller, and LD Thompson:Intramuscular fat and fatty acid composition of longissimus muscle from divergent pure breeds of cattle. Journal of Animal Science 2009,88:756-766.
[101]. Baker S, J Szasz, T Klein, P Kuber, C Hunt, J Glaze, D Falk, R Richard, J Miller, and R Battaglia:Residual feed intake of purebred Angus steers:Effects on meat quality and palatability. Journal of Animal Science 2006,84:938-945.
[102]. Silva J, L Patarata, and C Martins:Influence of ultimate pH on bovine meat tenderness during ageing. Meat Science 1999,52:453-459.
[103]. Shackelford SD, JB Morgan, HR Cross, and JW Savell:Iidentification of threshold levels for warner-bratzler shear force in beef top loin steaks. Journal of Muscle Foods 1991,2:289-296.
[104]. Boleman S, S Boleman. R Miller, J Taylor, H Cross, T Wheeler, M Koohmaraie, S Shackelford, M Miller, and R West:Consumer evaluation of beef of known categories of tenderness. Journal of Animal Science 1997,75:1521-1524.
[105]. Loken BA, RJ Maddock, MM Stamm, CS Schauer, I Rush, S Quinn, and GP Lardy:Growing rate of gain on subsequent feedlot performance, meat, and carcass quality of beef steers. Journal of Animal Science 2009,87:3791-3797.
[106]. Purchas RW, DL Burnham, and ST Morris:Effects of growth potential and growth path on tenderness of beef longissimus muscle from bulls and steers. Journal of Animal Science 2002,80: 3211-3221.
[107]. Marino R, M Albenzio, A della Malva, A Santillo, P Loizzo, and A Sevi:Proteolytic pattern of myofibrillar protein and meat tenderness as affected by breed and aging time. Meat Science 2013, 95:281-287.
[108]. Traore S, L Aubry, P Gatellier, W Przybylski, D Jaworska, K Kajak-Siemaszko, and V Sant6-Lhoutellier:Higher drip loss is associated with protein oxidation. Meat Science 2012,90: 917-924.
[109]. Farouk MM, NM Mustafa, G Wu, and G Krsinic:The "sponge effect" hypothesis:An alternative explanation of the improvement in the waterholding capacity of meat with ageing. Meat Science 2012,90:670-677.
[110]. Scollan N, J-F Hocquette, K Nuernberg, D Dannenberger, I Richardson, and A Moloney:Innovations in beef production systems that enhance the nutritional and health value of beef lipids and their relationship with meat quality. Meat Science 2006,74:17-33.
[111]. Dewhurst RJ, KJ Shingfield, MRF Lee, and ND Scollan:Increasing the concentrations of beneficial polyunsaturated fatty acids in milk produced by dairy cows in high-forage systems. Animal Feed Science and Technology 2006,131:168-206.
[112]. Varela A, B Oliete, T Moreno, C Portela, L Monserrrat, JA Carballo, and L Sanchez:Effect of pasture finishing on the meat characteristics and intramuscular fatty acid profile of steers of the Rubia Gallega breed. Meat Science 2004,67:515-522.
[113]. Wood JD, M Enser, AV Fisher, GR Nute, PR Sheard, RI Richardson, SI Hughes, and FM Whittington:Fat deposition, fatty acid composition and meat quality:A review. Meat Science 2008, 78:343-358.
[114]. Campo MM, GR Nute, JD Wood, SJ Elmore, DS Mottram, and M EnsenModelling the effect of fatty acids in odour development of cooked meat in vitro:part Ⅰ—sensory perception. Meat Science 2003,63:367-375.
[115]. Park RJ, AL FORD, and D Ratcliffe:Effect on meat flavor of period of feeding a protected lipid supplement to lambs. Journal of Food Science 1975,40:1217-1221.
[2].蒋洪茂：阉牛育肥的优缺点.科学种养2010,12：34.
[3]. Lazzaroni C and D Biagini:Effect of pre-and post-pubertal castration on Piemontese male cattle. II: Carcass measures and meat yield. Meat Science 2008,80:442-448.
[41. Morgan JB, TL Wheeler, M Koohmaraie, JD Crouse, and JW Savell:Effect of castration on myofibrillar protein turnover, endogenous proteinase activities, and muscle growth in bovine skeletal muscle. Journal of Animal Science 1993,71:408-414.
[51. Segato S, C Elia, C Mazzini, C Bianchi, and I Andrighetto:Effect of castration age on carcass traits and meat quality of Simmental bulls. Italian Journal of Animal Science 2010,4.
[6]. Champagne J, J Carpenter, J Hentges, A Palmer, and M Koger:Feedlot performance and carcass characteristics of young bulls and steers castrated at four ages. Journal of Animal Science 1969,29: 887-890.
[71. Worrell M, D Clanton, and CR Calkins:Effect of weight at castration on steer performance in the feedlot. Faculty Papers and Publications in Animal Science 1987:567.
[8]. Micol D, MP Oury, B Picard, JF Hocquette, M Briand, R Dumont, D Egal, R Jailler, H Dubroeucq, and J Agabriel:Effect of age at castration on animal performance, muscle characteristics and meat quality traits in 26-month-old Charolais steers. Livestock Science 2009,120:116-126.
[9].王景才,刘树军,吴爱芹等：全株玉米青贮料喂育肥牛的试验.黄牛杂志2003,29：27--28.
[10].蒋洪茂：我国黄牛生产特级(高档)牛肉的主要技术措施.科学种养2011,02：33--35.
[11]. Yang A, MJ Brewster, MC Lanari, and RK Tume:Effeet of vitamin E supplementation on a-tocopherol and P-carotene concentrations in tissues from pasture-and grain-fed cattle. Meat Science 2002,60:35-40.
[12]. Daly C, O Young, A Graafhuis, S Moorhead, and H Easton:Some effects of diet on beef meat and fat attributes. New Zealand Journal of Agricultural Research 1999,42:279-287.
[13]. Dunne PG, FJ Monahan, FP O'Mara, and AP Moloney:Colour of bovine subcutaneous adipose tissue:A review of contributory factors, associations with carcass and meat quality and its potential utility in authentication of dietary history. Meat Science 2009,81:28-45.
[14]. Pethick DW, BL Mclntyre, G Tudor, and JB Rowe:The partitioning of fat in ruminants:can nutrition be used as a tool to regulate marbling? Recent Advances in Animal Nutrition in Australia 1997,11: 151-158.
[15].薛华：肉牛常用饲料的特点.乡村科技2011,4：29.
[16]. Galyean M:Protein levels in beef cattle finishing diets:industry application, university research, and systems results. Journal of Animal Science 1996,74:2860-2870.
[171. Mitsumoto M, S Ozawa, T Mitsuhashi, and K Koide:Effect of dietary vitamin E supplementation for one week before slaughter on drip, colour and lipid stability during display in Japanese Black steer beef. Meat Science 1998,49:165-174.
[18]. Arnold R, K Scheller, S Arp, S Williams, D Buege, and D SchaeferEffect of long-or short-term feeding of alpha-tocopheryl acetate to Holstein and crossbred beef steers on performance, carcass characteristics, and beef color stability. Journal of Animal Science 1992,70:3055-3065.
[19].曹兵海,陈幼春,许尚忠等：我国的肉牛育肥技术模式与牛肉市场层次.中国畜牧杂志2007,43：55--58.
[20].沈迪非,江华：“入世”对我国国产牛肉市场的影响和对策.国际贸易问题2000,9：4-6.
[21]. Brown MS, CH Ponce, and R Pulikanti:Adaptation of beef cattle to high-concentrate diets: performance and ruminal metabolism. Journal of Animal Science 2006,84 Suppl:E25-33.
[22]. Odle J and DM Schaefer:Influence of rumen ammonia concentration on the rumen degradation rates of barley and maize. Br J Nutr 1987,57:127-38.
[23]. Satter LD and LL Slyter:Effect of ammonia concentration of rumen microbial protein production in vitro. British Journal of Nutrition 1974,32:199-208.
[24]. Steinfeld H and T Wassenaar:The role of livestock production in carbonand nitrogen cycles. Annu. Rev. Environ. Resour.2007,32:271-294.
[25]. Schroeder GF and EC Titgemeyer:Interaction between protein and energy supply on protein utilization in growing cattle:A review. Livestock Science 2008,114:1-10.
[26]. Brown MS, CR Krehbiel, ML Galyean, MD Remmenga, JP Peters, B Hibbard, J Robinson, and WM Moseley:Evaluation of models of acute and subacute acidosis on dry matter intake, ruminal fermentation, blood chemistry, and endocrine profiles of beef steers. Journal of Animal Science 2000,78:3155-68.
[27]. Bevans DW, KA Beauchemin, KS Schwartzkopf-Genswein, JJ McKinnon, and TA McAllister:Effect of rapid or gradual grain adaptation on subacute acidosis and feed intake by feedlot cattle. Journal of Animal Science 2005,83:1116-32.
[28].万发春,吴乃科,宋增福,杨在宾：不同能量水平对肉牛瘤胃代谢的影响研究.山东农业大学学报(自然科学版)2003,34：54-58.
[29]. Larick DK, HB Hedriek, ME Bailey, JE Williams, DL Hancock, and GB Garner:Flavor constituents of beef as influenced by forage-and grain-feeding. Journal of Food Science 1987,52:245-251.
[30]. Medeiros LC, RA Field, DJ Menkhaus, and WC Russell:Evaluation of range-grazed and concentraie-fed beef by a trained sensory panel, a household panel and a laboratory lest market group. Journal of Sensory Studies 1987,2:250-272.
[31]. Richardson JM, RG Wilkinson, and LA Sinclair:Synchrony of nutrient supply to the rumen and dietary energy source and their effects on the growth and metabolism of lambs. J.Anim. Sci 2003, 81:1332-1347.
[32]. Bach A, S Calsamiglia, and MD Stern:Nitrogen metabolism in the rumen. Journal of Dairy Science 2005,88:E9-E21.
[33]. Rode LM, DC Weakley, and LD Satter Effect of forage amount and particle size in diets of lactating dairy cows on site of digestion and microbial protein synthesis. J.Anim.Sci 1985 65:101-111.
[34]. Sarwar M, JL Firkins, and ML Eastridge:Effects of Varying Forage and Concentrate Carbohydrates on Nutrient Digestibilities and Milk Production by Dairy Cows. J.Dairy Sci 1992,66:811-820.
[35]. Wheeler WE and CH Noller:Effect of forage-to-concentrate ratio in complete feeds and feed intake on digestion of starch by dairy cows. J Dairy Sci 1975,58:1902-6.
[36]. Alhadhrami GJ and JT Hube:Effects of Alfalfa Hay of Varying Fiber Fed at 35 or 50% of Diet on Lactation and Nutrient Utilization by Dairy Cows. J. Dairy Sci 1992,75:3091-3099.
[37]. AOAC:Official methods of analysis,17th Edition. Association of Official Analytical Chemistry, Arlington, Virginia, USA.2000.
[38]. Van Soest PJ, JB Robertson, and BA Lewis:Methods for Dietary Fiber, Neutral Detergent Fiber, and Nonstarch Polysaccharides in Relation to Animal Nutrition. J Dairy Sci 1991,74:3583-3597.
[39]. Broderick GA and JH Kang:Automated simultaneous determination of ammonia and total amino acids in ruminal fluid and in vitro media. Journal of Dairy Science 1980,63:64-75.
[40]. Kim E, K-S Min, C-H Kim, Y Moon, S Kim, and S Lee:The effect of plant extracts on in-vitro ruminal fermentation, methanogenesis and methane-related microbes in the rumen. Asian Australas. J. Anim. Sci 2013,26:517-522.
[41]. Hoover WH and SR Stokes:Balancing carbohydrates and proteins for optimum rumen microbial yield. Journal of Dairy Science 1991,74:3630-44.
[42]. Van Houtert MFJ:The production and metabolism of volatile fatty acids by ruminants fed roughages:A review.. Anim Feed Sci Technol 1993,43:189-225.
[43]. NRC:Nutrient Requirements of Dairy Cattle.7th rev.ed. National Academy Press,Washington,DC. 2001.
[44]. Britton R and R Stock:Acidosis:A continual problem in cattle fed high grain diets. Cornell Nutr.Conf. Feed Manuf, Cornell Univ., Ithaca, NY.1989:8-15.
[45]. Owens FN, DS Secrist, WJ Hill, and DR Gill:Acidosis in cattle:A review. J. Anim. Sci.1998,76: 275-286.
[46]. Krause KM and GR Oetzel:Understanding and preventing subacute ruminal acidosis in dairy herds: A review. Anim. Feed Sci. Technol 2006,126:215-236.
[47]. Nagaraja TG and EC Titgemeyer:Ruminal acidosis in beef cattle:the current microbiological and nutritional outlook. Journal of Dairy Science 2007,90 Suppl 1:E17-38.
[48]. Yang WZ and KA Beauchemin:Increasing physically effective fiber content of dairy cow diets through forage proportion versus forage chop length:chewing and ruminal pH. J Dairy Sci 2009,92: 1603-15.
[49]. Yang WZ and KA Beauchemin:Altering physically effective fiber intake through forage proportion and particle length:digestion and milk production. J Dairy Sci 2007,90:3410-21.
[50]. Couderc JJ, DH Rearte, GF Schroeder, JI Ronchi, and FJ Santini:Silage chop length and hay supplementation on milk yield, chewing activity, and ruminal digestion by dairy cows. J Dairy Sci 2006,89:3599-608.
[51]. Preston H and D Leng:Matching ruminant production systems with available resources in the tropics and sub-tropics. Penambul Books 1987.
[52]. Clark JH, TH Klusmeyer, and MR Cameron:Microbial protein synthesis and flows of nitrogen fractions to the duodenum of dairy cows. Journal of Dairy Science 1992,75:2304-23.
[53]. Yang WZ, KA Beauchemin, and LM Rode:Effects of grain processing, forage to concentrate ratio, and forage particle size on rumen pH and digestion by dairy cows. Journal of Daily Science 2001, 84:2203-16.
[54]. Keady TWJ and CS Mayne:The effect of concentrate energy source on feed intake and rumen fermentation parameters of dairy cows offered a range of grass silages. Animal Feed Science and Technology 2001,90:117-129.
[55]. Murphy M, M Akerlind, and K Holtenius:Rumen fermentation in lactating cows selected for milk fat content fed two forage to concentrate ratios with hay or silage. J Dairy Sci 2000,83:756-64.
[56]. Nocek JE and S Tamminga:Site of digestion of starch in the gastrointestinal tract of dairy cows and its effect on milk yield and composition. J Dairy Sci 1991,74:3598-629.
[57]. Khorasani GR, EK Okine, and JJ Kennelly:Effects of forage source and amount of concentrate on rumen and intestinal digestion of nutrients in late-lactation cows. J Dairy Sci 2001,84:1156-65.
[58]. Dado RG and MS Allen:Intake limitations, feeding behavior, and rumen function of cows challenged with rumen fill from dietary fiber or inert bulk. J Dairy Sci 1995,78:118-33.
[59]. Andrae JG, CW Hunt, SK Duckett, LR Kennington, P Feng, FN Owens, and S Soderlund:Effect of high-oil corn on growth performance, diet digestibility, and energy content of finishing diets fed to beef cattle. J Anim Sci 2000,78:2257-62.
[60]. Pina DS, SC Valadares Filho, LO Tedeschi, AM Barbosa, and RF Valadares:Influence of different levels of concentrate and ruminally undegraded protein on digestive variables in beef heifers. J Anim Sci 2009,87:1058-67.
[61]. MacGregor CA, MR Stokes, WH Hoover, HA Leonard, LL Junkins, Jr., CJ Sniffen, and RW Mailman:Effect of dietary concentration of total nonstructural carbohydrate on energy and nitrogen metabolism and milk production of dairy cows. J Dairy Sci 1983,66:39-50.
[62]. Qiao GH, T Shao, CQ Yu, XL Wang, X Yang, XQ Zhu, and Y Lu:A comparative study at two different altitudes with two dietary nutrition levels on rumen fermentation and energy metabolism in Chinese Holstein cows. J Anim Physiol Anim Nutr (Berl) 2012.
[631. Voelker JA, GM Burato, and MS Allen:Effects of pretrial milk yield on responses of feed intake, digestion, and production to dietary forage concentration. J Dairy Sci 2002,85:2650-61.
[64]. Mabjeesh SJ, A Arieli, I Bruckental, S Zamwell, and H Tagari:Effect of ruminal degradability of crude protein and nonstructural carbohydrates on the efficiency of bacterial crude protein synthesis and amino acid flow to the abomasum of dairy cows. J Dairy Sci 1997,80:2939-49.
[65]. Khalili H and P Huhtanen:Sucrose supplements in cattle given grass silage-based diet.2. Digestion of cell wall carbohydrates. Animal Feed Science and Technology 1991,33:263-273.
[66]. Brown WF and DD Johnson:Effects of energy and protein supplementation of ammoniated tropical grass hay on the growth and carcass characteristics of cull cows. J Anim Sci 1991,69:348-57.
[67]. Russell JB and DB Dombrowski:Effect of pH on the efficiency of growth by pure cultures of rumen bacteria in continuous culture. Appl Environ Microbiol 1980,39:604-10.
[68]. Mould FL, ER 0rskov, and SO Mann:Associative effects of mixed feeds. I. effects of type and level of supplementation and the influence of the rumen fluid pH on cellulolysis in vivo and dry matter digestion of various roughages. Animal Feed Science and Technology 1983,10:15-30.
[69]. Erdman RA:Dietary buffering requirements of the lactating dairy cow:a review. Journal of Dairy Science 1988,71:3246-3266.
[70]. Orskov ER and FDB Hovell:Rumen digestion of hay (measured with dacron bags) by cattle given sugar cane or pangola hay. Tropical Anim. Production 1978,3.9-11.
[71]. Faix S, L Leng, M Szanyiova, and K Boda:Effect of dietary energy intake on tubular reabsorption of urea in sheep. Physiologia Bohemoslovaca 1988.37:493-501.
[72]. Mathis CP, RC Cochran, GL Stokka, JS Heldt, BC Woods, and KC Olson:Impacts of increasing amounts of supplemental soybean meal on intake and digestion by beef steers and performance by beef cows consuming low-quality tallgrass-prairie forage. J Anim Sci 1999,77:3156-62.
[73]. Koster HH, RC Cochran, EC Titgemeyer, ES Vanzant, I Abdelgadir, and G St-Jean:Effect of increasing degradable intake protein on intake and digestion of low-quality, tallgrass-prairie forage by beef cows. Journal of Animal Science 1996,74:2473-81.
[74]. Fike GD, DD Simms, RC Cochran, ES Vanzant, GL Kuhl, and RT Brandt, Jr.:Protein supplementation of ammoniated wheat straw:effect on performance and forage utilization of beef cattle. J Anim Sci 1995,73:1595-601.
[75]. Giraldez FJ, C Valuesb, R Pelaezb, P Frutosa, and AR Mantecona:The influence of digestible organic matter and nitrogen intake on faecal and urinary nitrogen losses in sheep. Livestock Prod.Sci 1997,51:183-190.
[76]. Kokkonen T, AT Tesfa, M Tuori, S Yrjanen, and L Syrjala-Qvist:Effect of concentrate crude protein level on grass silage intake, milk yield and nutrient utilisation by dairy cows in early lactation. Archives of Animal Nutrition 2002,56:213-27.
[77]. Broderick GA:Effects of varying dietary protein and energy levels on the production of lactating dairy cows. Journal of Dairy Science 2003,86:1370-81.
[78]. Haddad SG and MQ Husein:Nutritive value of lentil and vetch straws as compared with alfalfa hay and wheat straw for replacement ewe lambs. Small Rumin Res 2001,40:255-260.
[79]. Hof G, MD Vervoorn, PJ Lenaers, and S Tamminga:Milk urea nitrogen as a tool to monitor the protein nutrition of dairy cows. Journal of Dairy Science 1997,80:3333-3340.
[80]. Broderick GA and MK Clayton:A statistical evaluation of animal and nutritional factors influencing concentrations of milk urea nitrogen. J Dairy Sci 1997,80:2964-71.
[81]. Baker LD, JD Ferguson, and W Chalupa:Responses in urea and true protein of milk to different protein feeding schemes for dairy cows. J.Dairy Sci 1995,78:2424-2434.
[82]. Whitelaw FG, JS Milne, and XB Chen:The effect of a rumen microbial fermentation on urea and nitrogen metabolism of sheep nourished by intragastric infusion. Experimental Physiology 1991,76: 91-101.
[83]. Cuvelier C, JF Cabaraux, I Dufrasne, A Clinquart, JF Hocquette. L Istasse, and JL Hornick:Performance, slaughter characteristics and meat quality of young bulls from Belgian Blue, Limousin and Aberdeen Angus breeds fattened with a sugar-beet pulp or a cereal-based diet. Animal Science 2007,82:125-132.
[84]. Faucitano L, R Berthiaume, M D'Amours, D Pellerin, and DR Ouellet:Effects of corn grain particle size and treated soybean meal on carcass and meat quality characteristics of beef steers finished on a corn silage diet. Meat Science 2011,88:750-754.
[85]. Ludden PA, O Kucuk, DC Rule, and BW Hess:Growth and carcass fatty acid composition of beef steers fed soybean oil for increasing duration before slaughter. Meat Science 2009,82:185-192.
[86]. Warren HE, ND Scollan, M Enser, SI Hughes, RI Richardson, and JD Wood:Effects of breed and a concentrate or grass silage diet on beef quality in cattle of 3 ages. I:Animal performance, carcass quality and muscle fatty acid composition. Meat Science 2008,78:256-269.
[87]. Wu G, PK Davis, NE Flynn, DA Knabe, and JT Davidson:Endogenous synthesis of arginine plays an important role in maintaining arginine homeostasis in postweaning growing pigs. Journal of Nutrition 1997.127:2342-2349.
[88]. Grovum WL:Mechanisms explaining the effects of short chain fatty acids on feed intake in ruminants-osmotic pressure, insulin and glucagon. Ruminant physiology:digestion, metabolism, growth and reproduction. Proceedings 8th International Symposium on Ruminant Physiology.1995: 173-197.
[89]. Klosterman EW:Beef cattle size for maximum efficiency. Journal of Animal Science 1972,34: 875-880.
[90]. Ouyang SJ:Livestock and poultry breeds of Hunan Province. Hunan Science and Technology Press,Changsha.1984:54-60.
[91]. Felius M:Cattle breeds-an encyclopedia. Doetinchem, Netherlands 1995.
[92]. Paschal J, J Sanders, J Kerr, D Lunt, and A Herring:Postweaning and feedlot growth and carcass characteristics of Angus-, gray Brahman-, Gir-, Indu-Brazil-, Nellore-, and red Brahman-sired F1 calves. Journal of Animal Science 1995,73:373-380.
[93]. Alberti P, B Panea, C Sanudo, JL Olleta, G Ripoll, P Ertbjerg, M Christensen, S Gigli, S Failla, S Concetti, JF Hocquette, R Jailler, S Rudel, G Renand, GR Nute, R1 Richardson, and JL Williams:Live weight, body size and carcass characteristics of young bulls of fifteen European breeds. Livestock Science 2008,114:19-30.
[94]. Laborde FL, 1B Mandell, JJ Tosh, JW Wilton, and JG Buchanan-Smith:Breed effects on growth performance, carcass characteristics, fatty acid composition, and palatability attributes in finishing steers. Journal of Animal Science 2001,79:355-365.
[95]. Zhou GH, L Liu, XL Xiu, HM Jian, LZ Wang, BZ Sun, and BS Tong:Productivity and carcass characteristics of pure and crossbred Chinese Yellow Cattle. Meat Science 2001,58:359-362.
[96]. Lunstra DD and SE Echternkamp:Puberty in beef bulls:acrosome morphology and semen quality in bulls of different breeds. Journal of Animal Science 1982,55:638.
[97]. Henricks DM, TC Jenkins, JR Ward, CS Krishnan, and L Grimes:Endocrine responses and body composition changes during feed restriction and realimentation in young bulls. Journal of Animal Science 1994,72:2289-2297.
[98]. Arthur P, J Archer, D Johnston, R Herd, E Richardson, and P Parnell:Genetic and phenotypic variance and covariance components for feed intake, feed efficiency, and other postweaning traits in Angus cattle. Journal of Animal Science 2001,79:2805-2811.
[99]. Urick JJ, MD MacNEIL, and WL Reynolds:Biological type effects on postweaning growth, feed efficiency and carcass characteristics of steers. Journal of Animal Science 1991,69:490-497.
[100]. Dinh TTN, JR Blanton, DG Riley, CC Chase, SW Coleman, WA Phillips, JC Brooks, MF Miller, and LD Thompson:Intramuscular fat and fatty acid composition of longissimus muscle from divergent pure breeds of cattle. Journal of Animal Science 2009,88:756-766.
[101]. Baker S, J Szasz, T Klein, P Kuber, C Hunt, J Glaze, D Falk, R Richard, J Miller, and R Battaglia:Residual feed intake of purebred Angus steers:Effects on meat quality and palatability. Journal of Animal Science 2006,84:938-945.
[102]. Silva J, L Patarata, and C Martins:Influence of ultimate pH on bovine meat tenderness during ageing. Meat Science 1999,52:453-459.
[103]. Shackelford SD, JB Morgan, HR Cross, and JW Savell:Iidentification of threshold levels for warner-bratzler shear force in beef top loin steaks. Journal of Muscle Foods 1991,2:289-296.
[104]. Boleman S, S Boleman. R Miller, J Taylor, H Cross, T Wheeler, M Koohmaraie, S Shackelford, M Miller, and R West:Consumer evaluation of beef of known categories of tenderness. Journal of Animal Science 1997,75:1521-1524.
[105]. Loken BA, RJ Maddock, MM Stamm, CS Schauer, I Rush, S Quinn, and GP Lardy:Growing rate of gain on subsequent feedlot performance, meat, and carcass quality of beef steers. Journal of Animal Science 2009,87:3791-3797.
[106]. Purchas RW, DL Burnham, and ST Morris:Effects of growth potential and growth path on tenderness of beef longissimus muscle from bulls and steers. Journal of Animal Science 2002,80: 3211-3221.
[107]. Marino R, M Albenzio, A della Malva, A Santillo, P Loizzo, and A Sevi:Proteolytic pattern of myofibrillar protein and meat tenderness as affected by breed and aging time. Meat Science 2013, 95:281-287.
[108]. Traore S, L Aubry, P Gatellier, W Przybylski, D Jaworska, K Kajak-Siemaszko, and V Sant6-Lhoutellier:Higher drip loss is associated with protein oxidation. Meat Science 2012,90: 917-924.
[109]. Farouk MM, NM Mustafa, G Wu, and G Krsinic:The "sponge effect" hypothesis:An alternative explanation of the improvement in the waterholding capacity of meat with ageing. Meat Science 2012,90:670-677.
[110]. Scollan N, J-F Hocquette, K Nuernberg, D Dannenberger, I Richardson, and A Moloney:Innovations in beef production systems that enhance the nutritional and health value of beef lipids and their relationship with meat quality. Meat Science 2006,74:17-33.
[111]. Dewhurst RJ, KJ Shingfield, MRF Lee, and ND Scollan:Increasing the concentrations of beneficial polyunsaturated fatty acids in milk produced by dairy cows in high-forage systems. Animal Feed Science and Technology 2006,131:168-206.
[112]. Varela A, B Oliete, T Moreno, C Portela, L Monserrrat, JA Carballo, and L Sanchez:Effect of pasture finishing on the meat characteristics and intramuscular fatty acid profile of steers of the Rubia Gallega breed. Meat Science 2004,67:515-522.
[113]. Wood JD, M Enser, AV Fisher, GR Nute, PR Sheard, RI Richardson, SI Hughes, and FM Whittington:Fat deposition, fatty acid composition and meat quality:A review. Meat Science 2008, 78:343-358.
[114]. Campo MM, GR Nute, JD Wood, SJ Elmore, DS Mottram, and M EnsenModelling the effect of fatty acids in odour development of cooked meat in vitro:part Ⅰ—sensory perception. Meat Science 2003,63:367-375.
[115]. Park RJ, AL FORD, and D Ratcliffe:Effect on meat flavor of period of feeding a protected lipid supplement to lambs. Journal of Food Science 1975,40:1217-1221.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |