离子载体对杂种肉牛营养物质消化与氮平衡的影响

为了研究莫能霉素、盐霉素和拉沙里菌素3种离子载体对杂种肉牛营养物质消化和氮代谢的影响,以4头30～35月龄、体重380～450kg的西门塔尔×中国黄牛杂交一代公牛为试验动物,采用4×4拉丁方设计,进行消化试验和氮平衡试验。结果表明:莫能霉素、盐霉素和拉沙里菌素显著提高日粮粗纤维的消化率12.96%、16.24%和6.95%(P<0.05)和进食氮的沉积率24.67%、6.38%和23.22%(P<0.05);但对日粮干物质和粗蛋白的消化率、可消化氮的沉积率没有显著影响(P>0.05)。     

离子载体添加剂--莫能菌素对肉牛采食量的影响

离子载体添加剂是一类从链丝菌素细菌中分离出来的抗生素,它们能够改变瘤胃的发酵和微生物的代谢,从而使动物的生产性能改变。     

维持饲养水平下肉牛能量代谢的研究

为了验证我国《肉牛饲养标准(草案)》维持能量需要的准确性及探索用我国生产的开放式呼吸面罩测热装置进行肉牛能量代谢研究的可行性,作者从1985年8月至1986年3月在华南农业大学肉牛试验场分别用4头(第一试验期3头)西门塔尔×广东湛江黄牛杂交一代阉公牛进行了三期维持水平饲养试验,同时结合进行3期的消化代谢试验和4期呼吸代谢试验,根据饲养试验结果,按照我国肉牛饲养标准推荐的公式计算增重的净能需要,同时根据NRC(1984)《肉牛营养需要》代谢能用于增重和维持的效率计算出试验牛的维持代谢能和维持净能需要量。根据呼吸试验结果算出试牛每天的产热量(HP),与根据饲养试验结果算出     

增重埋植剂和离子载体对放牧阉牛生产性能的影响

舍饲和放牧牛皮下埋植玉米赤霉醇与其他增重剂一样有效,饲喂离子载体对饲料转化率和生长速度有良好影响。拉沙里菌素是与莫能菌素作用方式相似的离子载体。离子载体与增重剂的作用方式完全不同,其相互作用如何现尚不清楚。本项研究旨在评定两水平玉米赤霉醇或单用17β-雌二醇或17β-雌二醇与拉沙里菌素联用对1岁阉牛生长速度的影响。材料与方法将75头1岁西门塔尔杂种牛按体重分为5组,每组牛按5×3因子设计     

增喂离子载体对反刍家畜营养消化与吸收的影响

离子载体是一种含有某些阳离子的可溶性脂质聚合物,易于通过生物膜。目前畜牧业常用的离子载体添加剂主要有莫能菌素、拉沙里菌素、盐霉素和溶胞菌素。这类物质被反刍家畜广泛用作促生长剂而禽类则用于防治球虫病。随着离子载体添加剂在反刍动物方面应用研究的深入与发展,离子载体对反刍动物营养消化与吸收的影响机制越来越引起人们的重视。虽然至今有些机制尚不清楚,但现有的研究结果已经表明,离子载体可以通     

离子载体在反刍动物生产中的应用

本文对莫能霉素、拉沙里菌素、莱特洛霉素丙酸盐、泰脱那霉素和溶胞菌素等5种离子载体在反刍动物生产上的应用研究进展及使用注意问题做了综述,为离子载体在反刍动物生产中的正确合理使用提供理论指导和参考。     

离子载体药物对家鸭球虫病治疗效果比较

鸭球虫病是由多种鸭艾美耳球虫寄生于鸭肠上皮细胞引起的一种原虫病,给养禽业带来巨大的经济损失。为了解离子型抗球虫药物对鸭球虫病的防治效果,在模拟家鸭笼养的环境条件下,选用莫能霉素、盐霉素、马杜拉霉素、拉沙里菌素、那拉霉素等5种离子载体药物进行试验。试验结果表明,5种离子载体类药物对鸭球虫病均有很好的防治效果,并且马拉霉素等对家鸭的增重也有一定效果。     

5种离子载体类药物对鸭球虫病的疗效试验

我国自林昆华等 1982年报道 [1] 北京鸭暴发球虫病以来 ,相继有广东、广西、福建、江苏、江西、四川等地先后报道鸭球虫病在当地流行的情况。鸭球虫病是鸭的一种急性寄生原虫病 ,发病急 ,死亡率高 ,常给养鸭业带来较大的经济损失。林昆华等 (1982 ) [1] ,卢胜明等 (1985 ) [2 ] ,殷佩云等 (1983) [4] 先后报道磺胺类药物对防治鸭球虫病有显著效果 ,但磺胺类药物不宜长期使用 ,故寻求另类的抗鸭球虫病的药物 ,是待解决的科研课题。蒋金书等 (1990 ) [3 ] 曾做过这方面的尝试。我们应用对鸡球虫病有良好效果的五种离子载体类药物进行实验 ,观…     

不同采气方法对六氟化硫示踪法测定肉牛甲烷排放量的影响

为研究不同采气方法对六氟化硫示踪法测定牛甲烷(CH4)排放的影响,试验选取18头6月龄夏洛来杂交牛作为研究对象,随机分成A、B、C三组,每组6头(实际采样时每组随机选用牛头数为5头),饲喂相同日粮,采用六氟化硫(SF6)示踪技术测定牛CH4排放量。A组为对照组,使用牛扼法采气;B组和C组采用定时定点法采气,B组每2h采集1次,采集24h;C组每1h采集1次,采集12h(每天10∶00~22∶00),连续采样5d。试验期30d。结果表明:三组测得的CH4排放量差异不显著(P0.05)。采样期内三种采气方法所测得CH4排放量变化趋势基本一致。因此,可根据试验需要采用定时定点采气法测定牛CH4排放量。     

粗料型日粮真胃灌注棕榈油对肉牛能量和蛋白质转化效率影响的初步研究

用安装真胃瘘管体重 370kg的 4头阉牛 ,按 4× 4完全拉丁方设计 ,用KB 1型自控大型呼吸测热室 ,研究真胃灌注不同水平棕榈油 (10 0 g/d、2 0 0 g/d、30 0g/d和 0 g/d)对能量、蛋白质转化效率及血液生化指标的影响。结果表明 :(1)真胃灌注棕榈油显著降低HP/ME ,并以灌注 2 0 0 g最低 ,分别比对照组、10 0 g和 30 0 g组低 12 76 % (P <0 0 1)、6 53% (P <0 0 5)和 0 48% (P >0 0 5) ;(2 )真胃灌注棕榈油的平均Kf值比未灌注组增加 50 91% (P <0 0 1) ,灌注 2 0 0 g和 30 0 g组的Kf值高于 10 0g组 (P <0 0 5) ,但 2 0 0 g组与 30 0 g组差异不显著 (P >0 0 5) ;(3)与未灌注组相比 ,真胃灌注棕榈油可使能量、脂肪和蛋白质沉积量显著增加 (P <0 0 1)。真胃灌注 2 0 0g组的能量沉积最高 ,分别比对照组、10 0 g组和 30 0g组提高 7 16MJ/d(P <0 0 1)、3 82MJ/d(P <0 0 5)和 0 2 8MJ/d(P >0 0 5)。脂肪沉积量分别提高 172 35g/d(P <0 0 1)、92 0 8g/d(P <0 0 1)和10 54g/d(P >0 0 5)。 (4 )真胃灌注棕榈油可显著提高氮沉积 (P <0 0 5) ,沉积氮 (RN ,g/d)或可消化氮 (DN)转化为RN的效率 (% )与棕榈油灌注量 (X ,g/d)均存在线性正相关关系 ,RN(g/d) =5 0 1 0 0 1X     

不同饲养水平下灌注氨基酸对阉牛氮代谢的影响

选择 6头体重 5 0 0～ 6 0 0kg ,安装有瘤胃、十二指肠前端和回肠末端瘘管的阉牛 ,分 3期依次饲喂以玉米、棉粕和氨化稻草为原料配合的 3种不同饲养水平的日粮。每种饲养水平下 ,依次从十二指肠灌注 4种不同的氨基酸混合液 ,测定相应的氮平衡值、血清尿素和血清游离氨基酸浓度。其中 ,饲喂高水平日粮时 ,4种灌注处理分别为 :Lys+Met+Thr、Met+Thr、Lys+Thr和Lys+Met;饲喂中等水平和低水平日粮时 ,4种灌注处理分别为 :Lys+Met+Val、Met+Val、Lys+Val和Lys+Met。结果显示 ,3种饲养水平下 ,不同灌注处理对氮平衡值有显著影响 (P <0 0 5 )。在高水平日粮条件下 ,与Lys +Met+Thr处理相比 ,回撤Lys、Met和Thr时 ,氮平衡值分别减少了 10 2 3、8 83和 7 2 8g/d(P <0 0 5 ) ;在中等水平的日粮条件下 ,与Lys+Met+Val处理相比 ,回撤Lys、Met和Val时 ,氮平衡值分别减少了 5 4 1、3 4 1和 1 6 0 g/d(P <0 0 5 ) ;在低水平日粮条件下 ,与Lys +Met+Val处理相比 ,回撤Lys、Met和Val时 ,氮平衡值分别减少了 8 4 5、5 14和 2 78g/d(P <0 0 5 ) ,各种回撤处理间的氮平衡也差异显著 (P <0 0 5 )。 3种饲养水平下 ,血清尿素、血清总游离氨基酸和除被撤氨基酸外的各种游离氨基酸浓度随灌注处理不同而变化的趋势与氮平     

不同进食水平对生茸期梅花鹿能量代谢的影响

采用梯度饲养试验、消化代谢试验及呼吸测热试验等方法 ,对成年梅花鹿生茸期能量代谢规律进行了研究。结果表明 ,随着能量进食水平的提高 ,梅花鹿体沉积能显著增加 ;梅花鹿日产热量与进食能量水平呈强直线相关 ;甲烷能产生量随能量进食水平的增加而增加。     

饲粮能量水平对青山羊能量代谢和产热量的影响

本试验旨在研究饲粮不同能量水平对青山羊能量代谢和产热量的影响。试验选取体型基本一致、健康的4~5岁龄青山羊公羊12只,随机分为3个处理,每个处理4只。试验采取单因素试验设计,3个处理饲粮消化能水平依次为8.91、9.79、10.62 MJ/kg,各组均限饲,且投料量一致。试验期预试期7 d,正试期3 d。结果表明:9.79 MJ/kg饲粮能量水平组能量表观消化率、代谢率、每天CO2排出量、O2消耗量、非蛋白质CO2排出量和非蛋白质O2消耗量都显著高于其他两组(P<0.05);9.79 MJ/kg能量水平组每天的总产热量和非蛋白质产热量显著高于其他两组(P<0.05);本试验同时求得青山羊公羊绝食代谢产热量的估测值为259.66 kJ/kgW0.75,维持代谢能需要量的估测值为450.82 kJ/kgW0.75。综合分析,9.79 MJ/kg为青山羊公羊较适宜的能量水平。     

Effects of Perilla Cake and Rapeseed Meal Instead of Soybean Meal in Diet on Apparent Digestibility and Nitrogen Metabolism of Beef Cattle

The purpose of this experiment was to study the effect of perilla cake and rapeseed meal instead of soybean meal on the apparent digestibility and nitrogen metabolism of beef cattle.20 Qinchuan beef cattle of about 12 months old with similar weight and good health were selected and divided into 5 groups with 4 cattle in each group according to the univariate randomized block design.Five different protein feeds treatments were 31% soybean meal,36% rapeseed meal,14% perilla cake+24% rapeseed meal,28% perilla cake+12% rapeseed meal and 42% perilla cake,respectively.The experiment lasted 120 days,of which the pre-feeding period was 15 days and the trial period was 105 days.During the test,the daily intake of nitrogen,urine nitrogen and fecal nitrogen,the apparent digestibilities of dry matter (DM),organic matter (OM),neutral detergent fiber (NDF) and acid detergent fiber (ADF) of each test cow were determined.The results showed that:① The 42% perilla cake group had the highest nitrogen intake,and the 36% rapeseed meal group had the lowest nitrogen content,and the differences between the groups were not significant (P>0.05).The manure nitrogen in 36% rapeseed meal group was significantly higher than 28% and 42% perilla cake groups (P<0.05),and there was no significant difference with 31% soybean meal group and 14% perilla cake group (P>0.05).② The 42% perilla cake group had the highest sedimentary nitrogen,which was significantly different from other groups (P<0.05),and the 31% soybean meal group was significantly higher than 36% rapeseed meal group (P<0.05).③ The apparent digestibility of DM and ADF in 42% perilla cake group were significantly higher than those in 31% soybean meal group and 36% rapeseed meal group (P<0.05).There was no significant difference in apparent digestibility of DM,OM and NDF between 14% and 28% perilla cake groups (P>0.05).④ The content of urea nitrogen in 14% perilla cake group was significantly higher than 31% soybean meal group and 42% perilla cake group (P<0.05),and it was not significantly different from the 36% rapeseed meal group and 28% perilla cake group (P>0.05).The 31% soybean meal group had significantly higher nitrosate nitrogen content than 36% rapeseed meal group and 42% perilla cake group (P<0.05),and these three groups were significantly higher than 14% and 28% perilla cake groups (P<0.05).Allantoin nitrogen in 31% soybean meal group was significantly higher than 42% perilla cake group (P<0.05),and there was no significant difference from the other three groups (P>0.05).There was no significant differences in creatine nitrogen,microbial nitrogen predicted value,urea nitrogen/urine nitrogen,creatine nitrogen/urine nitrogen,and purine derivative nitrogen/urine nitrogen among all groups (P>0.05).In summary,in this test,when 42% perilla cake was used instead of 31% soybean meal in the concentrate,the beef cattle had the highest nitrogen deposition,which was 3.65 g/d higher than 31% soybean meal group.The apparent digestibility of DM,OM,NDF and ADF were 3.45%,2.22%,6.56%,and 10.98% higher than 31% soybean meal group,respectively.     

日粮中紫苏饼、菜籽粕代替豆粕对肉牛养分表观消化率及氮代谢的影响

试验旨在研究日粮中紫苏饼、菜籽粕代替豆粕对肉牛养分表观消化率及氮代谢的影响。选择20头体重相近、健康状况良好的12月龄左右的秦川肉牛（母牛）为试验动物,按照单因素随机区组设计,将20头试验牛分为5组,每组4头牛。不同试验组日粮中分别添加以31%豆粕（对照）、36%菜籽粕、14%紫苏饼+24%菜籽粕、28%紫苏饼+12%菜籽粕和42%紫苏饼为蛋白质原料配制的5种不同的精饲料。试验持续120 d,其中预饲期15 d,正试期105 d。试验期间,测定每头试验牛每天的摄入氮、尿氮及粪氮,测定日粮中干物质（DM）、有机物（OM）、中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）的表观消化率。结果表明：① 42%紫苏饼组摄入氮含量最高,36%菜籽粕组最低,但各组间氮含量差异不显著（P>0.05）;36%菜籽粕组的粪氮显著高于28%和42%紫苏饼组（P<0.05）,且与31%豆粕组和14%紫苏饼组差异不显著（P>0.05）;② 42%紫苏饼组的沉积氮最高,与其他各组均差异显著（P<0.05）,其中31%豆粕组显著高于36%菜籽粕组（P<0.05）;③ 42%紫苏饼组的DM、ADF表观消化率显著高于31%豆粕组和36%菜籽粕组（P<0.05）,14%和28%紫苏饼组的DM、OM和NDF的表观消化率均差异不显著（P>0.05）;④ 14%紫苏饼组尿液中尿素氮含量显著高于31%豆粕组和42%紫苏饼组（P<0.05）,且与36%菜籽粕组和28%紫苏饼组差异不显著（P>0.05）;31%豆粕组尿液中马尿酸氮含量显著高于36%菜籽粕组和42%紫苏饼组（P<0.05）,而这3组均显著高于14%和28%紫苏饼组（P<0.05）;31%豆粕组的尿囊素氮含量显著高于42%紫苏饼组（P<0.05）,与其他3组差异不显著（P>0.05）;各组的肌酸氮、微生物氮预测值、尿素氮/尿氮、肌酸氮/尿氮和嘌呤衍生物氮/尿氮均没有显著差异（P>0.05）。综上,本试验条件下,精料中用42%紫苏饼代替31%豆粕,肉牛氮沉积最高,比对照组高3.65 g/d;DM、OM、NDF、ADF的表观消化率分别比对照组高3.45%、2.22%、6.56%、10.98%。     

Predicting metabolizable energy from digestible energy for growing and finishing beef cattle and relationships to the prediction of methane

Reliable predictions of metabolizable energy (ME) from digestible energy (DE) are necessary to prescribe nutrient requirements of beef cattle accurately. A previously developed database that included 87 treatment means from 23 respiration calorimetry studies has been updated to evaluate the efficiency of converting DE to ME by adding 47 treatment means from 11 additional studies. Diets were fed to growing-finishing cattle under individual feeding conditions. A citation-adjusted linear regression equation was developed where dietary ME concentration (Mcal/kg of dry matter [DM]) was the dependent variable and dietary DE concentration (Mcal/kg) was the independent variable: ME = 1.0001 × DE – 0.3926; r² = 0.99, root mean square prediction error [RMSPE] = 0.04, and P < 0.01 for the intercept and slope. The slope did not differ from unity (95% CI = 0.936 to 1.065); therefore, the intercept (95% CI = −0.567 to −0.218) defines the value of ME predicted from DE. For practical use, we recommend ME = DE – 0.39. Based on the relationship between DE and ME, we calculated the citation-adjusted loss of methane, which yielded a value of 0.2433 Mcal/kg of dry matter intake (DMI; SE = 0.0134). This value was also adjusted for the effects of DMI above maintenance, yielding a citation-adjusted relationship: CH₄, Mcal/kg = 0.3344 – 0.05639 × multiple of maintenance; r² = 0.536, RMSPE = 0.0245, and P < 0.01 for the intercept and slope. Both the 0.2433 value and the result of the intake-adjusted equation can be multiplied by DMI to yield an estimate of methane production. These two approaches were evaluated using a second, independent database comprising 129 data points from 29 published studies. Four equations in the literature that used DMI or intake energy to predict methane production also were evaluated with the second database. The mean bias was substantially greater for the two new equations, but slope bias was substantially less than noted for the other DMI-based equations. Our results suggest that ME for growing and finishing cattle can be predicted from DE across a wide range of diets, cattle types, and intake levels by simply subtracting a constant from DE. Mean bias associated with our two new methane emission equations suggests that further research is needed to determine whether coefficients to predict methane from DMI could be developed for specific diet types, levels of DMI relative to body weight, or other variables that affect the emission of methane.     

动物解耦联蛋白基因的同源性分析及对能量代谢的作用

文中分析比较11种物种解耦联蛋白(UCPs)基因核苷酸序列同源性,综述了UCPs产热机制和UCPs基因在脂肪和肌肉组织中的表达调控。为深入开展UCPs对能量代谢调控方面的研究奠定基础。     

谷氨酸对脂多糖刺激断奶仔猪肠道能量代谢的影响

本试验旨在研究谷氨酸(Glu)对脂多糖(LPS)刺激断奶仔猪肠道能量代谢的影响。选择24头断奶仔猪分为4个组,分别为对照组、LPS组、LPS+1.0%Glu组和LPS+2.0%Glu组,每组6个重复,每个重复1头猪。于试验第28天,试验组猪注射100μg/kg BW LPS,对照组注射等量的生理盐水,4 h后屠宰,取肠道样品待测。结果表明:1)与对照组相比,LPS刺激导致断奶仔猪空肠三磷酸腺苷(ATP)、腺苷酸池(TAN)含量和能荷(EC)显著降低(P0.05),一磷酸腺苷(AMP)/ATP值显著升高(P0.05);与LPS组相比,LPS+2.0%Glu组显著提高了空肠ATP、二磷酸腺苷(ADP)和TAN含量(P0.05)。2)与对照组相比,LPS刺激导致断奶仔猪回肠柠檬酸合成酶和α-酮戊二酸脱氢酶系活性极显著降低(P0.01),空肠α-酮戊二酸脱氢酶系活性有降低趋势(P=0.092);与LPS组相比,除LPS+1.0%Glu组回肠柠檬酸合成酶活性显著降低(P0.05)外,Glu对空肠和回肠三羧酸循环关键酶活性无显著影响(P0.05)。3)与对照组相比,LPS刺激导致空肠过氧化物酶体增殖物激活受体γ辅激活因子1α(PGC1α)及回肠沉默信号调控因子1(Sirt1)和PGC1α的mRNA表达量极显著降低(P0.01);与LPS组相比,LPS+2.0%Glu组有提高空肠PGC1α(P=0.067)和回肠Sirt1(P=0.053)mRNA表达量的趋势,LPS+1.0%Glu组有提高回肠Sirt1 mRNA表达量的趋势(P=0.070)。由此可见,Glu可以改善LPS刺激导致的肠道能量损耗状态。     

Effect of divergence in residual methane emissions on feed intake and efficiency,growth and carcass performance,and indices of rumen fermentation and methane emissions in finishing beef cattle

Residual expressions of enteric emissions favor a more equitable identification of an animal’s methanogenic potential compared with traditional measures of enteric emissions. The objective of this study was to investigate the effect of divergently ranking beef cattle for residual methane emissions (RME) on animal productivity, enteric emissions, and rumen fermentation. Dry matter intake (DMI), growth, feed efficiency, carcass output, and enteric emissions (GreenFeed emissions monitoring system) were recorded on 294 crossbred beef cattle (steers = 135 and heifers = 159; mean age 441 d (SD = 49); initial body weight (BW) of 476 kg (SD = 67)) at the Irish national beef cattle performance test center. Animals were offered a total mixed ration (77% concentrate and 23% forage; 12.6 MJ ME/kg of DM and 12% CP) ad libitum with emissions estimated for 21 d over a mean feed intake measurement period of 91 d. Animals had a mean daily methane emissions (DME) of 229.18 g/d (SD = 45.96), methane yield (MY) of 22.07 g/kg of DMI (SD = 4.06), methane intensity (MI) 0.70 g/kg of carcass weight (SD = 0.15), and RME 0.00 g/d (SD = 0.34). RME was computed as the residuals from a multiple regression model regressing DME on DMI and BW (R² = 0.45). Animals were ranked into three groups namely high RME (>0.5 SD above the mean), medium RME (±0.5 SD above/below the mean), and low RME (>0.5 SD below the mean). Low RME animals produced 17.6% and 30.4% less (P < 0.05) DME compared with medium and high RME animals, respectively. A ~30% reduction in MY and MI was detected in low versus high RME animals. Positive correlations were apparent among all methane traits with RME most highly associated with (r = 0.86) DME. MY and MI were correlated (P < 0.05) with DMI, growth, feed efficiency, and carcass output. High RME had lower (P < 0.05) ruminal propionate compared with low RME animals and increased (P < 0.05) butyrate compared with medium and low RME animals. Propionate was negatively associated (P < 0.05) with all methane traits. Greater acetate:propionate ratio was associated with higher RME (r = 0.18; P < 0.05). Under the ad libitum feeding regime deployed here, RME was the best predictor of DME and only methane trait independent of animal productivity. Ranking animals on RME presents the opportunity to exploit interanimal variation in enteric emissions as well as providing a more equitable index of the methanogenic potential of an animal on which to investigate the underlying biological regulatory mechanisms.