2-甲基丁酸对西门塔尔牛增重、日粮养分消化和甲烷排放的影响

试验旨在研究2-甲基丁酸对西门塔尔牛日粮养分消化率、增重性能及甲烷排放的影响。选择12月龄左右、发育正常及体重相近的西门塔尔公牛36头,随机分为4组,即对照组及试验1～3组,每组9头牛,分别饲喂添加0、1.0、2.0及3.0 g/kg体重2-甲基丁酸的玉米秸秆日粮,测定日粮养分消化率、西门塔尔牛增重性能及甲烷的排放情况。试验期70 d。结果表明,试验2、3组西门塔尔牛有机物质（OM）消化率较对照组显著提高（P<0.05）;3个试验组粗蛋白质（CP）消化率均较对照组显著提高（P<0.05）,但无氮浸出物（NFE）消化率在各组间差异不显著（P>0.05）;试验2组西门塔尔牛中性洗涤纤维（NDF）消化率显著高于对照组和试验1组（P<0.05）,而其酸性洗涤纤维（ADF）消化率则显著高于其他各组（P<0.05）;试验2、3组西门塔尔牛试验期间平均日增重显著高于对照组（P<0.05）,但其在试验1组与对照组间差异不显著（P>0.05）;与对照组相比,试验2组的干物质采食量显著降低（P<0.05）,试验2、3组料重比也显著降低（P<0.05）;在日粮中添加2-甲基丁酸后,西门塔尔牛的甲烷排放呈降低趋势,试验2、3组排放的甲烷能显著低于对照组（P<0.05）。由以上结果推断,在日粮中添加2-甲基丁酸可促进西门塔尔牛的生长及对营养物质消化,同时可有效降低甲烷排放,2-甲基丁酸的适宜添加水平为2.0 g/kg体重。     

日粮添加苹果酸对西门塔尔牛日粮养分消化率的影响

选用4头体重约500kg．年龄3岁装有永久性瘤胃瘘管的西门塔尔阉牛．采用4×4拉丁方设计．以混合精料和玉米秸秆为基础日粮．研究不同添加水平的苹果酸（0、70、140和210g／d）对西门塔尔牛日粮养分表观消化率的影响。结果表明：140g／d组和210g／d组有机物质、粗脂肪、无氮浸出物、中性洗涤纤维和酸性洗涤纤维表观消化率显著高于对照组（P〈0．05）。在本试验条件下．苹果酸的适宜添加水平为140g／d．     

添加柠檬酸对西门塔尔牛日粮养分消化率的影响

选用4头年龄4岁、体况良好、平均体重500k，装有永久性瘤胃瘘管的中国西门塔尔阉牛，采用4×4拉丁方设计，以混合精料和玉米秸秆为基础日粮．研究柠檬酸（0、100、200和300g／d）对日粮养分表观消化率的影响。结果表明：200g／d组精饲料干物质（DM）、粗脂肪（EE）、无氮浸出物（NFE）、中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）较对照组显著提高（P〈0．05）。根据试验结果推断日粮中柠檬酸的适宜添加水平为200g/d。     

烟酸铬对西门塔尔牛日粮养分消化率的影响

试验选用4头体重(500±20)kg,年龄3.5岁,装有永久性瘤胃瘘管的西门塔尔牛阉牛,采用4×4拉丁方试验设计,以混合精料和风干玉米秸秆为基础日粮,研究日粮中添加烟酸铬(0、40、80、120 mg/d)对日粮养分消化率的影响。结果表明:日粮添加烟酸铬80 mg/d组的干物质(DM)、有机物质(OM)、粗脂肪(EE)、粗蛋白质(CP)、无氮浸出物(NFE)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的表观消化率较对照组显著提高(P<0.05)。因此在本试验条件下日粮中烟酸铬适宜添加水平为80 mg/d。     

丙酸钙对西门塔尔牛日粮养分表观消化率的影响

选用4头体重500kg,年龄3．5岁的中国西门塔尔牛阉牛,采用44拉丁方设计,以混合精料和玉米秸秆为基础日粮,研究丙酸钙（0、100、200和300g／d）对日粮养分表观消化率的影响。结果表明：日粮添加丙酸钙200g／d组干物质（DM）、有机物质（OM）、粗蛋白质（CP）、粗脂肪（EE）、无氮浸出物（NFE）、中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）表观消化率与对照组相比均显著提高（P〈0。05）;高于其它丙酸钙处理组,但差异不显著（P〉0．05）。根据实验结果推断,日粮中丙酸钙的适宜添加水平为200g／d。     

异丁酸对西门塔尔牛瘤胃营养物质降解的影响

选用4头平均体重420kg,年龄2.5岁装有永久性瘤胃瘘管的中国西门塔尔牛(阉牛),采用4×4拉丁方设计,以混合精料和玉米秸秆为基础日粮,研究日粮添加异丁酸(0、0.02g/kgWd-1、0.04g/kgWd-1和0.06g/kgWd-1)对瘤胃营养物质降解的影响。结果表明:0.02g/kgWd-1组豆粕干物质、有机物和粗蛋白质动态降解率显著高于对照组(P<0.05);0.04g/kgWd-1组玉米秸干物质、有机物、中性洗涤纤维和酸性洗涤纤维的降解率显著提高(P<0.05)。根据本试验结果推断日粮中异丁酸的适宜添加水平为0.04g/kgWd-1。     

硒酵母对西门塔尔牛日粮养分消化代谢和血清生化指标的影响

本试验旨在研究硒酵母对西门塔尔牛营养物质消化代谢和血清生化指标的影响。选用16头平均体重420 kg,年龄2.5岁的西门塔尔牛阉牛,采用随机区组设计分为4组,以硒酵母为硒源,分别在日粮中添加硒0、0.3、0.6和0.9 mg/kg。结果表明:日粮养分表观消化率、矿物元素表观存留率、消化氮和沉积氮/消化氮比例均以0.3 mg/kg与0.6 mg/kg组较高(P<0.05);0.6 mg/kg组甘油三酯显著提高,处理组血糖显著增加,0.6 mg/kg和0.9 mg/kg组白蛋白增加(P<0.05),总胆固醇、总蛋白和尿素氮差异不显著(P>0.05);0.6 mg/kg和0.9 mg/kg组血清GOT和GPT含量显著提高(P<0.05),AKP、ACP和LDH差异均不显著(P>0.05);处理组GSH-px活性显著提高(P<0.05),以0.6 mg/kg组最高;0.6 mg/kg和0.9 mg/kg组MDA显著降低(P<0.05);0.6 mg/kg组GSH含量显著增加(P<0.05);0.6 mg/kg和0.9 mg/kg组血清硒含量显著增加(P<0.05)。日粮以硒酵母为硒源时,添加硒0.6 mg/kg显著促进营养物质消化代谢和提高机体抗氧化能力,建议日粮加硒为0.6 mg/kg。[动物营养学报,2007,19(4):379-385]     

不同饲料铜源对西门塔尔牛日粮养分消化率的影响

选用5头体重420 kg、2.5岁、装有永久性瘤胃瘘管的西门塔尔牛阉牛,采用5×5拉丁方试验设计,研究硫酸铜、富铜酵母、赖氨酸铜、蛋氨酸铜和包被铜(日粮中铜含量为8 mg/kg)时日粮齐分消化率的影响.结果表明:日粮有机物质、粗蛋白质、粗脂肪、无氮浸出物、中性洗涤纤维和酸性洗涤纤维消化率均以赖氨酸铜组、富铜酵母组和蛋氨酸铜组较高,包被铜组次之.硫酸铜组最差.可消化氮、沉积氮和沉积氮/消化氮以蛋氨酸铜组和赖氨酸铜组较高,显著高于包被铜组和硫酸铜组(P<0.05),但与富铜酵母组差异不显著(P>0.05),包被铜组显著高于硫酸铜组(P<0.05).综合比较,有机铜效果较好,其次为包被铜,硫酸铜较差.     

西门塔尔牛模式化饲养日粮及养分转化率的测定分析

对５０头西门塔尔泌乳母牛的日粮进行了为期６０ｄ的实测,结果如下：奶牛日均采食混合精料６．７ｋｇ,青贮玉米（带穗）２０．０ｋｇ,青干草５．０ｋｇ;其营养成分含量为干物质１６．３８ｋｇ,奶牛能量单位３３．７７,可消化粗蛋白１．３３ｋｇ,钙９３．３２ｇ,磷７１．１６ｇ;日粮主要养分转化为乳成分的效率为干物质１２．８２％,奶牛能量单位转化为乳能量５１．９１％,可消化粗蛋白４５．４１％,钙２４．３８％,磷２     

异丁酸对西门塔尔牛瘤胃发酵及尿嘌呤衍生物的影响

本文旨在研究异丁酸对西门塔尔牛瘤胃pH、NH3-N、VFA和营养物质降解率及尿嘌呤衍生物浓度的影响。选用4头平均体重420 kg,年龄2.5岁装有永久性瘤胃瘘管的中国西门塔尔牛阉牛,采用4×4拉丁方设计,以混合精料和风干玉米秸秆为基础日粮,在基础日粮中分别添加异丁酸0、0.02、0.04和0.06 g/(kgW.d)。结果表明:各组瘤胃pH差异不显著(P>0.05),0.04 g/(kgW.d)组和0.06 g/(kgW.d)组NH3-N浓度极显著低于对照和0.02 g/(kgW.d)组(P<0.01);0.02 g/(kgW.d)组豆粕干物质、有机物和粗蛋白质动态降解率显著高于对照组(P<0.05);0.04 g/(kgW.d)组玉米秸干物质、有机物、中性洗涤纤维和酸性洗涤纤维的降解率显著提高(P<0.05),0.04 g/(kgW.d)组瘤胃乙酸、乙酸/丙酸、总挥发性脂肪酸和尿嘌呤衍生物显著增加(P<0.05)。根据试验结果推断日粮中异丁酸的适宜添加水平为0.04 g/(kgW.d)。     

Effects of isobutyrate supplementation on ruminal microflora,rumen enzyme activities and methane emissions in Simmental steers

The objective of this study was to evaluate the effects of isobutyrate supplementation on rumen microflora, enzyme activities and methane emissions in Simmental steers consuming a corn stover‐based diet. Eight ruminally cannulated Simmental steers were used in a replicated 4 × 4 Latin square experiment. The treatments were control (without isobutyrate), low isobutyrate (LIB), moderate isobutyrate (MIB) and high isobutyrate (HIB) with 8.4, 16.8 and 25.2 g isobutyrate per steer per day respectively. Isobutyrate was hand‐mixed into the concentrate portion. Diet consisted of 60% corn stover and 40% concentrate [dry matter (DM) basis]. Dry matter intake (averaged 9 kg/day) was restricted to a maximum of 90% of ad libitum intake. Population of total bacteria, cellulolytic bacteria and anaerobic fungi were linearly increased, whereas that of protozoa and total methanogens was linearly reduced with increasing isobutyrate supplementation. Real‐time PCR quantification of population of Ruminococcus albus, Ruminococcus flavefaciens, Butyrivibrio fibrisolvens and Fibrobacter succinogenes was linearly increased with increasing isobutyrate supplementation. Activities of carboxymethyl cellulase, xylanase and β‐glucosidase were linearly increased, whereas that of protease was linearly reduced. Methane production was linearly decreased with increasing isobutyrate supplementation. Effective degradabilities of cellulose and hemicellulose of corn stover were linearly increased, whereas that of crude protein in diet was linearly decreased with increasing isobutyrate supplementation. The present results indicate that isobutyrate supplemented improved microflora, rumen enzyme activities and methane emissions in steers. It was suggested that the isobutyrate stimulated the digestive micro‐organisms or enzymes in a dose‐dependent manner. In the experimental conditions of this trial, the optimum isobutyrate dose was approximately 16.8 g isobutyrate per steer per day.     

精补料能量对西杂肉牛育肥性能和成本的影响

选择40头体重接近(400.8±32.1)kg的周岁西杂肉牛随机分为4个试验组,饲喂从5.27 MJ/kg到5.90 MJ/kg增重净能的4组精补料,经过150 d育肥试验全部屠宰测定,探讨4组增重净能精补料饲喂杂交肉牛的育肥性能和成本。结果表明,饲喂增重净能5.90 MJ/kg和5.69 MJ/kg精补料的杂交肉牛总增重、净肉增重、料重比和料肉比均优于饲喂增重净能5.27 MJ/kg和5.48 MJ/kg精补料的杂交肉牛;饲喂增重净能5.90 MJ/kg和5.69 MJ/kg精补料的杂交肉牛单位增重成本比增重净能5.27 MJ/kg和5.48 MJ/kg的平均降低11.71%,单位净肉增重成本平均降低17.33%;饲喂增重净能5.90 MJ/kg精补料的各项试验指标最好,饲喂增重净能5.27 MJ/kg精补料的最差(P0.05,P0.01)。由此结论,高增重净能的精补料明显提高杂交肉牛育肥和产肉性能、改善总增重和净肉增重的饲料效率和成本。     

精补料增重净能对西杂肉牛育肥性能和成本的影响

选择48头体重相近([192.90±26.38)kg]的8～10月龄西门塔尔杂交肉牛随机分为4个试验组,通过添加大豆油饲喂按等同梯度从5.94 MJ/kg递增到6.57 MJ/kg增重净能的等同蛋白质和必需氨基酸的精补料,探讨4组高增重净能的精补料饲喂杂交肉牛的育肥性能和成本。150 d育肥试验的结果表明,饲喂6.36 MJ/kg增重净能精补料3和5.94 MJ/kg精补料1的杂交肉牛全期日增重分别为1.26 kg和1.19 kg,精料重比分别为2.95和3.16,增重耗精料成本占摄入成本分别为79.53%和84.51%(P<0.05、P<0.01),显著差异来自精补料增重净能的二元曲线效应;饲喂6.57 MJ/kg增重净能精补料4和6.15 MJ/kg精补料2的杂交肉牛全期育肥性能在数据上优于精补料1和低于精补料3(P>0.05)。由此结论,在饲喂黄贮玉米秸秆条件下,6.36 MJ/kg增重净能的精补料3明显提高杂交肉牛育肥性能、饲料效率和育肥利润空间;过高增重净能的精补料4没有表现出最佳育肥效果。     

不同栽培时期收割的玉米青贮料对肉牛生长性能、养分消化及甲烷排放的影响

本研究旨在用不同栽培时期收割的玉米青贮后作为原料饲喂肉牛,评估其对肉牛生长性能、养分消化及甲烷排放的影响.试验将(528.98±0.21)kg的75头荷斯坦肉牛随机分为5组,每组3个重复,每个重复5头.T1～T4组饲喂不同栽培时期收割的玉米青贮料,同时每天每头补充2.5?kg浓缩料,T5组自由采食浓缩料,同时每天每头补...     

Effects of animal and supplement characteristics on average daily gain of grazing beef cattle

Effects of animal gender and age, use of a growth stimulant, and supplementation with grain alone or grain plus other substances on ADG by growing beef cattle grazing bermudagrass paddocks with sod-seeded rye, wheat, and ryegrass were determined. Two grazing experiments (Exp. 1: late winter through mid-spring; Exp. 2: late spring through mid-summer) were conducted. Experiment 1 used 96, 12- to 13-mo-old Simmental-cross calves (heifers, 240 kg; steers, 272 kg), half of which were implanted with zeranol. Within each implant treatment, cattle received no supplement or .5% BW (DM) of ground corn alone or plus a mix of protein meals, zinc sulfate, thiamin-HCl, or salt. Daily gain was higher (P less than .05) with than without supplementation and was similar (P greater than .10) among supplement treatments. In Exp. 2, 96 crossbred beef steers, approximately 7 (230 kg) or 15 mo old (250 kg), were not supplemented (control) or received .5% BW (DM) of ground corn on d 1 to 84 (C-C), corn plus a protein meal mix on d 1 to 84 (CP-CP), corn on d 43 to 84 (O-C), corn plus the protein meal mix on d 43 to 84 (O-CP), or corn on d 1 to 42 and corn plus the protein meal mix on d 43 to 84 (C-CP). Daily gain on d 1 to 84 was affected (P less than .05) by supplement, age, implant, and the supplement x implant interaction (nonimplanted: .37, .56, .68, .40, .49, and .49; implanted: .37, .62, .54, .49, .70, and .71 kg for control, C-C, CP-CP, O-C, O-CP, and C-CP, respectively).     

Effects of dietary supplementing tannic acid in the ration of beef cattle on rumen fermentation,methane emission,microbial flora and nutrient digestibility

Four adult Simmental male cattle (376 ± 9.0 kg initial BW), fitted with permanent rumen cannulas, were used in a 4 × 4 Latin square design to investigate the effects of dietary supplementing tannic acid (TA) on rumen fermentation, methane (CH₄) production, rumen microbes, nutrient digestibility and plasma biochemical parameters. Four levels of TA, that is 0, 6.5, 13.0 or 26.0 g/kg dry matter (DM), were added to the basal ration (composed of corn silage and concentrate mixture) as experimental treatments respectively. Each experimental period consisted of a 12‐day adaptation phase followed by a 3‐day sampling phase. The results showed that supplementing TA at 26.0 g/kg DM decreased the relative abundance of protozoa, methanogens and Ruminococcus albus to the total ruminal bacterial 16S rDNA in beef cattle (p < 0.05). The results also showed that supplementing TA at 6.5, 13.0 or 26.0 g/kg DM decreased (p < 0.01) the CH₄ production (l/kg DM intake) by 11.1%, 14.7% and 33.6% respectively. Supplementing TA at 13.0 or 26.0 g/kg DM decreased the ratio of acetate to propionate and ammonia nitrogen (NH₃–N) (p < 0.05) and tended to decrease the total volatile fatty acid (VFA) concentration of rumen fluid (p = 0.07). Supplementing TA at 26.0 g/kg DM decreased DM and organic matter (OM) digestibility (p < 0.05), supplementing TA at 6.5, 13.0 or 26.0 g/kg DM decreased (p < 0.01) crude protein (CP) digestibility by 5.0%, 8.6% and 15.7%, respectively, and supplementing TA at 6.5, 13.0 or 26.0 g/kg DM increased (p < 0.05) the plasma total antioxidant capability. It was concluded that supplementing TA in the ration of beef cattle decreased the CH₄ production and digestibility of CP of beef cattle. Supplementing TA could be an effective option to mitigate CH₄ emission form cattle, further research is necessary to study the effects of TA on the performance of cattle.     

复合植物精油对肉牛生长性能、养分消化及氮代谢的影响

文章旨在评估复合植物精油对肉牛生长性能、营养物质表观消化及氮代谢的影响.试验将平均体重为(203.16±0.29)kg的108头肉牛随机分为3组,每组36头,每6头牛为1个重复.对照组饲喂全混合日粮,同时自由采食小麦秸秆,T1组和T2组分别饲喂全混合日粮+30和60 mg/kg植物精油,自由采食小麦秸秆.经过28周的饲...     

赛乐硒对西门塔尔牛营养物质消化和氮平衡的影响

选用7头体重420kg、2．5岁的中国西门塔尔牛。采用7×7拉丁方设计,研究添加赛乐硒（7．5、15和22．5m$e／d）和亚硒酸钠（7．5、15和22．5mgSe／d）对日粮营养物质消化和氮平衡的影响。结果表明,7．5～15mg／d赛乐硒组OM、CP、EE、NFE、NDF和ADF表观消化率显著提高,15-22．5m岛『d亚硒酸钠组显著降低。赛乐硒较亚硒酸钠显著提高了采食氮、消化氮、沉积氮和消化氮,沉积氮比例。以上结果表明,赛乐硒较无机硒能更有效促进营养物质的消化与利用。提高抗氧化能力,其适宜添加量为7．5—15mg／d。     

包被硒对西门塔尔牛日粮营养物质消化代谢的影响

选用4头装有永久性瘤胃瘘管的西门塔尔阉牛,采用4×4拉丁方设计,研究包被硒(0、0.3、0.6和0.9mg/kgDM)对日粮营养物质消化代谢的影响。结果表明:0.6mg/kg组日粮养分的表观消化率显著高于对照组(P<0.05);日粮DN、RN、RN/DN显著高于对照组(P<0.05),以0.6mg/kg组最高;0.6mg/kg组Se、Ca、P、Cu、Fe和Mn的存留率均显著高于对照(P<0.05)。兼顾基础日粮含硒量,建议以包被硒为硒源时日粮硒水平为0.67mgSe/kgDM。     

日粮补充苹果酸对牛瘤胃发酵和养分消化代谢的影响

选用8头体重462 kg、年龄3岁、装有永久性瘤胃瘘管的西门塔尔牛阉牛,采用4×4重复拉丁方设计,对照组饲喂基础日粮,处理组分别在基础日粮基础上添加苹果酸70,140和210 g/d,研究苹果酸对西门塔尔牛瘤胃发酵、尿嘌呤衍生物含量、日粮养分表观消化率、能量代谢及氮平衡的影响。结果表明,140和210 g/d组瘤胃pH值显著低于对照组,瘤胃乙酸摩尔比、乙酸/丙酸、氨态氮浓度和乳酸含量显著低于对照组和70 g/d组(P<0.05),瘤胃总挥发性脂肪酸浓度、丙酸和丁酸摩尔比显著高于对照组和100 g/d组(P<0.05)。140 g/d组玉米秸秆干物质、有机物质、中性洗涤纤维和酸性洗涤纤维瘤胃有效降解率显著高于对照组(P<0.05);210 g/d组混合精料干物质、有机物质和粗蛋白质瘤胃有效降解率显著低于对照组、70和140 g/d组(P<0.05)。140 g/d组尿囊素和尿嘌呤衍生物含量显著高于70和210 g/d组及对照组(P<0.05);140和210 g/d组有机物质、粗脂肪、无氮浸出物、中性洗涤纤维和酸性洗涤纤维表观消化率显著高于对照组(P<0.05);140 g/d组消化能、代谢能、沉积能及沉积能/消化能显著高于对照组(P<0.05);140 g/d组沉积氮显著高于对照组(P<0.05)。综合各项指标,苹果酸的适宜添加水平为140 g/d。