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1.
Background：This experiment was conducted to determine the nutritive value of corn from the north of China for growing pigs.The experiment examined corn variety（LS1,LS2,LS3 and LS4）grown in one location,drying method（sun dried and artificially dried）and different drying temperatures.Corn harvested at 20-25%moisture was dried to about 12%moisture by sun drying and artificially drying at 80,100,or 120℃ in a fluidized bed dryer.Ninety-six barrows（average BW of 33.4 ± 2.7 kg）were housed in individual metabolism crates to facilitate separate collection of feces and urine.A five-day collection period followed a seven-day diet acclimation period.Results：The results indicated that variety significantly influenced（P〈0.01）the 1,000 kernel weight of corn but not the bulk weight.Variety also influenced the available energy content（digestible energy of dry matter,P〈0.01;metabolisable energy of dry matter,P〈0.01）and digestibility of organic matter（P〈0.01）,as well as dry matter（P〈0.01）and gross energy（GE）content（P〈0.02）.The drying method of corn significantly influenced the 1,000 kernel weight（P〈0.01）,bulk weight（P〈0.01）and digestibility of ether extract（EE）（P〈0.01）.No effect of drying temperature on the digestibility of organic matter,dry matter（DM）,crude protein（CP）,neutral detergent fiber（NDF）,acid detergent fiber（ADF）and gross energy was observed,but gelatinization（P〈0.05）and test weight（P〈0.01）decreased with an increase in temperature.Conclusions：Variety has a significant impact on the nutritive value of corn for growing pigs,and greater attention needs to be paid to these influences in the assignment of the nutritive value of corn given to growing pigs.  相似文献   

2.
Four crossbred （Duroc x Landrace x Yorkshire） boars, weighing an average of 22.40 ± 1.08 kg and fitted with permanent catheters in their portal and mesenteric veins as well as their carotid artery,were utilized in a 4 × 4 latin square design experiment in order to investigate the effects of different starch sources （maize ,brown rice, sticky rice, and resistant starch） on the absorption of energy sources through the portal vein. Portal blood flow averaged 30.68, 28.40, 29.99, and 30. 12 mL/min per kg BW for pigs fed the maize, brown rice, sticky rice, and resistant starch diets, respectively, and did not dif- fer （P 〉 0.05） between treatments. The absorptions of glucose, plasma ammonia, and total amino acids were significantly lower （P 〈 0.05 ） in pigs fed the resistant starch diet than pigs fed the other starch sources. In contrast, significantly （ P 〈 0.05 ） higher amounts of propionate and total volatile fatty acids were absorbed from the portal vein of pigs fed resistant starch than pigs fed diets based on maize, brown rice, or sticky rice. In addition, significantly （P 〈 0.05） more lactic acid was absorbed from the portal vein by pigs fed the sticky rice diet than pigs fed the other three diets. The energy absorbed from the portal vein in the form of glucose and amino-N as well as the total energy absorbed was significantly （P 〈 0.05） lower in pigs fed the resistant starch diet than pigs fed the other three starch sources. In contrast, the amount of energy absorbed in the form of volatile fatty acids was significantly （P 〈 0.05 ） higher in pigs fed resistance starch than pigs fed the other three starch sources. The total energy absorbed through the portal vein as a percentage of the gross energy and digestible energy consumed in pigs fed maize were 50.8% and 54.6%, respectively, which were significantly （P 〈 0.05 ） higher than the values in pigs fed resistant starch （41.5% and 46.6% respectively）. The results indicate that energy is absorbed in different forms and with different utilization efficiencies in the digestive tract of pigs as a result of feeding different starch sources. Starch sources supplying most of their energy in the form of glucose had higher energy utilization efficiencies, while starch sources supplying most of their energy in the form of volatile fatty acids or lactic acid had lower energy utilization efficiencies.  相似文献   

3.
The development of a metabolizable energy (ME) system for horses is described. Predictive equations for gross energy and digestible energy (DE) are revisited. The relationship between feed protein content and renal energy losses and the relationship between feed fibre content and methane energy losses were analysed in a literature review to develop predictive equations for ME. In horses, renal energy losses are much higher than losses by methane energy. Renal energy losses were correlated more strictly to protein intake than to digestible protein intake. The reason probably is that per gram of digestible crude protein energy losses are higher for roughage than for concentrates presumably because phenolic acids of forage cell walls contribute to higher urinary energy losses. However, digestibility of protein is lower in forages than in concentrates. The net result is a rather constant urinary energy loss of 0.008 MJ/g of crude protein in the feed. Methane losses in horses are smaller than in ruminants, presumably because of reductive acidogenesis in hind gut fermentation. Methane energy losses in equines are closely related to crude fibre intake. The mean methane energy losses amount to 0.002 MJ ME/g of crude fibre which can be used to correct for methane losses. Both corrections can be made for any predictive equation for DE. Metabolizable energy is then calculated as follows: ME MJ/kg = DE MJ/kg – 0.008 MJ/g crude protein – 0.002 MJ/g crude fibre. The equation of Zeyner and Kienzle (2002) to predict DE was adapted as mentioned above to predict ME: ME (MJ/kg dry matter) = ?3.54 + 0.0129 crude protein+0.0420 crude fat?0.0019 crude fibre+0.0185 N‐free extract (crude nutrients in g/kg dry matter).  相似文献   

4.
应用套算法估测肉羊精饲料代谢能   总被引：1，自引：0，他引：1  
本试验旨在应用套算法建立肉羊精饲料代谢能估测模型。选取66只18月龄体重为(49.6±1.3)kg的杜泊×小尾寒羊F1代去势肉羊,采用完全随机区组设计分为11组,包括1个基础饲粮组和10个试验饲粮组,每组6只羊。通过消化代谢试验(为期8 d)和气体代谢试验(为期3 d)并结合套算法计算10种精饲料的消化能和代谢能,建立精饲料代谢能和其概略养分或可消化养分之间的模型。结果表明,1)10种精饲料总能、酸性洗涤纤维含量与消化能呈显著相关(P0.05),有机物含量与消化能达到极显著相关(P0.01);精饲料概略养分与代谢能之间则无显著相关性(P0.05)。2)10种精饲料的可消化养分与代谢能存在极显著相关(P0.01),所建立的预测方程为:ME=-1.907+1.344DE+1.321DDM-5.347DOM-2.093DADF(R2=0.845,n=60,P0.01);ME=-2.105+1.349DE-6.577DOM(R2=0.842,n=60,P0.01)。[ME为代谢能(MJ/kg),DE为消化能(MJ/kg),DDM为可消化干物质(%),DOM为可消化有机物(%),DA DF为可消化酸性洗涤纤维(%)。]综上所述,本试验条件下无法利用精饲料概略养分预测其代谢能,通过精饲料的可消化养分可准确预测其代谢能。  相似文献   

5.
Energy expenditure was measured in four geldings (433 to 520 kg) during submaximal exercise on a racetrack using a mobile open-circuit indirect respiration calorimeter. A total of 304 5-min measurements of O2 consumed and CO2 produced were taken. Measurements were made with and without riders. The amount of energy expended by the horses was exponentially related to speed and was proportional to the body weight of the riderless horse or the combined weight of the horse plus rider and tack. Total energy expended by the four horses walking, trotting, cantering was best described by the equation: Y = e3.02 + .0065X where Y = energy expended (cal X kg-1 X min-1) and X = speed (m/min). Digestible energy (DE) required above maintenance was calculated as (Formula: see text).  相似文献   

6.
A comparative slaughter experiment was conducted to determine the energy values of cassava chips for weanling pigs. A basal, highly fortified diet was fed to all pigs at 3% body weight daily. Treatments consisted of the addition of cassava chips at 0, 1, and 2% of body weight daily. The apparent digestion coefficients (ADC) for dry matter and energy increased but the ADC for nitrogen decreased with the addition of cassava chips to the basal diet. Digestible energy per gram decreased linearly and quadratically (P less than .01), but metabolizable energy and net energy per gram remained constant with the addition of cassava chips. Metabolizable energy as a percentage of digestible energy increased linearly and quadratically (P less than .01) with the addition of cassava chips to the basal diet. Daily gain of nitrogen, ether extract, and energy increased linearly (P less than .01) as cassava chips were added to the basal diet, but daily gain of ash remained relatively constant. Pooled energy values determined for cassava chips in kcal/g of dry matter were: gross energy, 4.04; digestible energy, 3.58; metabolizable energy, 3.48; nitrogen-corrected metabolizable energy, 3.22; and net energy, 2.57. Net energy of cassava chips for weanling pigs is close to that of corn.  相似文献   

7.
本试验旨在建立奶牛饲料的康奈尔净碳水化合物-蛋白质体系(Cornell net carbohydrate and protein system,CNCPS)预测小肠可消化粗蛋白质(uCP)含量的数学模型.采用CNCPS体系对13种饲料蛋白质组分进行划分,采用移动尼龙袋法测定13种饲料小肠uCP含量,试验动物为3头带有永久性瘤胃瘘管和十二指肠瘘管的荷斯坦奶牛,采用单因素试验设计.结果表明:1)豆粕、棉籽粕、菜籽粕、葵花籽粕、芝麻粕、玉米胚芽粕、米糠、米糠饼、米糠粕、大麦、麦麸、玉米和玉米麸质饲料的uCP含量分别为390.32、321.90、297.21、230.50、388.62、177.49、85.53、116.78、134.74、80.47、128.26、70.28和66.65g/kg.2)所有试验饲料实测uCP含量与CNCPS各蛋白质组分含量的回归方程为:uCP=-4.11+6.48PA+7.73PB1+5.72PB2+8.26PB3+5.11PC(R2=0.9972,P＜0.01);蛋白质饲料实测uCP含量与CNCPS各蛋白质组分含量的回归方程为:uCP=12.79+5.47PA+7.04PB1+9.74PB2+8.14PB3(R2=0.9987,P＜0.01);能量饲料实测uCP含量与CNCPS各蛋白质组分含量的回归方程为:uCP=14.80+8.55PA+6.27PB2+17.64PB3(R2=0.9874,P＜0.01).3)蛋白质饲料、能量饲料及所有试验饲料的实测uCP含量与CNCPS各蛋白质组分含量的相关系数均高于0.95,蛋白质饲料实测uCP含量与CNCPS各蛋白质组分含量的相关系数高于能量饲料.结果提示,利用CNCPS体系划分的各蛋白质组分含量预测饲料uCP含量是可行的,且预测蛋白质饲料的uCP含量比预测能量饲料的uCP含量更准确.  相似文献   

8.
试验探讨用化学分析法预测大豆蛋白类饲料猪消化能值。选取体重(35±2)kg、遗传基础相似的健康杜×长×大三元杂交阉公猪8头,采用2个4×4拉丁方设计,运用套算法测定豆饼、豆粕、干法膨化全脂大豆等8种大豆蛋白类饲料的表观消化能(DE),分析并计算出各种饲料的常规成分。结果表明:(1)在大豆蛋白类饲料猪消化能值回归预测中,ADF是最佳预测因子。(2)最佳预测方程为①DE(MJ/kg,DM基础)=16.407-85.982ADF+0.328GE(R2=0.88,RSD=0.264%,P<0.01);②DE(MJ/kg,DM基础)=30.319-89.999ADF+9.659SCHO-184.115Ash(R2=0.95,RSD=0.189%,P<0.01);③DE(MJ/kg,DM基础)=23.882-84.418ADF-7.877NFE+19.71CF(R2=0.95,RSD=0.281%,P<0.01),上述最佳方程经检验适用于与本试验类似的饲料。  相似文献   

9.
生长期秦川牛能量代谢规律与需要量研究   总被引：2，自引：0，他引：2  
本试验旨在研究生长期秦川牛能量代谢规律与需要量。选择30头体况良好、体重[(336.33±18.28)kg]相近的生长期秦川牛公牛,随机分为5组,每组6头牛,分别饲喂按我国《肉牛饲养标准》(NY/T 815—2004)提供的预期平均日增重900 g/d所需净能的85.0%(Ⅰ组)、92.5%(Ⅱ组)、100.0%(Ⅲ组)、107.5%(Ⅳ组)、115.0%(Ⅴ组)配制的5种试验饲粮。采用饲养试验和消化代谢试验测定秦川牛生长性能及能量代谢指标,并建立消化能和代谢能需要量预测模型。预试期10 d,正试期42 d。结果表明,Ⅲ组秦川牛平均日增重为880.15 g/d,较预期的结果略低;Ⅳ组平均日增重达到最大值(1 160.10 g/d),能量利用效率最高;总能消化率、总能代谢率和消化能代谢率平均值分别为(76.44±3.23)%、(66.75±3.16)%、(87.31±0.54)%;秦川牛的消化能和代谢能需要量的回归方程分别为:DER=0.778W0.75+37.05ADG;MER=0.668W0.75+33.49ADG[DER为消化能需要量(M J/d),MER为代谢能需要量(M J/d),W0.75为单位代谢体重(kg),ADG为平均日增重(kg/d)]。综合得出,生长期秦川牛的维持消化能和代谢能需要量分别为0.778、0.668 MJ/(kg W0.75·d),每千克增重的消化能和代谢能需要量分别为37.05、33.49 M J。  相似文献   

10.
本研究旨在评定白酒糟的营养成分及在生长猪上的消化能(DE)和代谢能(ME),并基于其所含化学组分建立白酒糟在生长猪上DE和ME的预测模型。选取78头健康、体重(52.1±3.6)kg的杜×长×大三元杂交去势公猪,随机分配到1个玉米-豆粕型基础日粮和12个白酒糟(替代基础日粮供能组分的30%)待测日粮处理中进行消化代谢试验,每个处理6个重复,每个重复1头猪,用全收粪尿法和套算法测定其对生长猪的DE和ME值。进一步分析每个样品的化学成分与其有效能值的关系,用逐步回归法建立了12个白酒糟样品DE和ME的预测方程。结果表明:饲喂基础下,12个白酒糟样品的DE为3.79~8.81 MJ/kg,ME为3.54~8.15 MJ/kg;白酒槽DE的最佳预测方程为DE(MJ/kg)=38.46-0.63×粗灰分-0.11×粗纤维-1.14×总能-0.03×中性洗涤纤维(R^2=0.81),ME的最佳预测方程为ME(MJ/kg)=41.86-0.75×粗灰分-1.51×总能+0.20×粗脂肪-0.05×粗纤维(R^2=0.74)。  相似文献   

11.
本试验应用套算法分析肉羊常用蛋白质饲料原料中的营养成分含量和可消化营养成分对有效能值的影响,基于饲料原料中的营养成分含量和可消化营养成分建立蛋白质饲料原料代谢能(ME)的预测模型。选取36只22月龄、体重为(52.6±1.4)kg的杜泊×小尾寒羊F1代杂交去势肉羊,采用完全随机区组设计分为6个处理,包括1个基础饲粮处理和5个试验饲粮处理,每个处理6只羊。利用消化代谢试验和呼吸代谢试验并结合套算法计算5种蛋白质饲料原料的消化能(DE)和ME,并分析蛋白质饲料原料DE、ME与该原料中营养成分[干物质(DM)、有机物(OM)、总能(GE)、粗蛋白质(CP)、粗脂肪(EE)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)]和可消化营养成分[可消化干物质(DDM)、可消化有机物(DOM)、可消化粗蛋白质(DCP)、可消化粗脂肪(DEE)、可消化中性洗涤纤维(DNDF)、可消化酸性洗涤纤维(DADF)]含量之间的相关关系。结果表明:饲料原料中的OM、DDM、DOM、DCP含量与DE和ME均存在极显著正相关(P0.01);另外,DADF与DE存在极显著负相关(P0.01),与ME存在显著负相关(P0.05)。通过饲料原料中的营养成分含量预测ME的方程为:ME(MJ/kg)=-82.855+2.391OM(%)+1.802EE(%)-6.21GE(MJ/kg)-0.121ADF(%)(R2=0.910,n=30,P0.01);通过饲料原料中的可消化营养成分含量预测ME的方程为:ME(MJ/kg)=-5.564+30.526DOM(%)+55.402DEE(%)(R2=0.841,n=30,P0.01);通过饲料原料中的可消化营养成分含量与DE共同预测ME的方程为:ME=-5.787+1.126DE(MJ/kg)+20.769DEE(%)(R2=0.879,n=30,P0.01)。综上所述,在本试验中,蛋白质饲料原料中的部分营养成分和可消化营养成分含量与ME之间存在显著相关,可通过饲料原料中的营养成分和可消化营养成分含量对肉羊蛋白质饲料原料的ME进行有效预测。  相似文献   

12.
本试验旨在研究育肥后期锦江去势公牛的能量代谢规律及需要量。在育肥前期不同能量水平饲喂的基础上(育肥前期5种肉牛日粮综合净能(NEmf)依次为6.02、6.38、6.74、7.10、7.46 MJ/kg,每组10头牛,育肥116 d)继续育肥,育肥前期试验结束后,保持分组不变,挑选35头体型接近、体重(355.94±35.11) kg锦江牛继续育肥。按照中国《肉牛饲养标准》(NY/T 815-2004)中350 kg肉牛日增重1.2 kg/d所需净能的100%(A组)、106%(B组)、112%(C组)、118%(D组)、124%(E组)配制5种不同能量水平的试验日粮,5种日粮的NEmf依次为6.21、6.58、6.95、7.33、7.70 MJ/kg。采用饲养试验和消化代谢试验测定育肥后期锦江去势公牛生长性能及能量代谢指标,并建立消化能和代谢能能量需要模型。预试期10 d,正试期128 d。结果表明:①D、E组育肥后期锦江去势公牛的总能采食量较其他组显著降低(P<0.05)。②B组肥后期锦江去势公牛能量利用效率最高,总能消化率、总能代谢率分别为90.59%和83.36%。③育肥后期锦江去势公牛日增重与消化能采食量和代谢能采食量存在高度线性正相关(R^2=0.997、R^2=0.993),其消化能、代谢能需要量的回归方程分别为:DE_m=0.770W0.75+40.088×ADG;ME_m=0.645W0.75+38.603×ADG(其中DE为消化能总需要量(MJ/d);ME为代谢能总需要量(MJ/d);W0.75为单位代谢体重(kg);ADG为平均日增重(kg/d))。综上所述,育肥后期锦江牛的维持消化能总需要量(DE_m)和代谢能总需要量(ME_m)分别为0.770、0.645 MJ/(kg W0.75·d),每千克增重的消化能和代谢能需要量分别为40.088、38.603 MJ。  相似文献   

13.
Background： This study was conducted to evaluate the apparent metabolizable energy （AME） and true metabolizable energy （TME） contents in 30 sources of corn distillers dried grains with solubles （DDGS） in adult roosters, and establish the prediction equations to estimate the AME and TME value based on its chemical composition and color score. Methods： Twenty-eight sources of corn DDGS made from several processing plants in 11 provinces of China and others imported from the United States. DDGS were analyzed for their metabolizable energy （ME） contents, measured for color score and chemical composition （crude protein, crude fat, ash, neutral detergent fiber, acid detergent fiber）, to predict the equation of ME in DDGS. A precision-fed rooster assay was used, each DDGS sample was tube fed （50 g） to adult roosters. The experiment was conducted as a randomized incomplete block design with 3 periods. Ninety-five adult roosters were used in each period, with 90 being fed the DDGS samples and 5 being fasted to estimate basal endogenous energy losses. Results： Results showed that the AME ranged from 5.93 to 12.19 MJ/kg, TME ranged from 7.28 to 13.54 MJ/kg. Correlations were found between ME and ash content （-0.64, P 〈 0.0]） and between ME and yellowness score （0.39, P 〈 0.05） of the DDGS samples. Furthermore, the best-fit regression equation for AME content of DDGS based on chemical composition and color score was AME = 6.57111 ＋ 0.5]475 GE - 0.10003 NDF ＋ 0.1 3380 ADF ＋ 0.07057 fat - 0.57029 ash - 0.02437 L （R^2 = 0.70）. The best-fit regression equation for TME content of DDGS was TME = 7.92283 ＋ 0.51475 GE - 0.10003 NDF ＋ 0.13380 ADF ＋ 0.07057 fat - 0.57029 ash - 0.02437 L （R2 = 0.70）. Conclusions： This experiment suggested that measuring the chemical composition and color score of a corn DDGS sample may provide a quality parameter for identifying corn DDGS sources energy digestibility and metabolizable energy content.  相似文献   

14.
The aim of this study was to develop a simple and reproducible in vitro method for predicting the apparent energy digestibility of dry extruded dog foods. The proposed method is based on the two-step multienzymatic incubation assay described by [Boisen, S., 1991: In Vitro Digestion for Pigs and Poultry, M. F. Fuller (ed.). CAB International, Wallingford, 135-146], with some modifications adapted to dogs' digestion characteristics. The method consisted in two consecutives incubations, first one during 2 h with pepsin (10 mg/g of food sample) in acid pH and second one during 4 h with pancreatin (100 mg/g of food sample). The undigested residue obtained was collected in a filtration unit and then dried and ashed. The in vitro percentage of organic matter disappearance (in vitro dOM) of 54 dry extruded commercial dog foods was determined and used as predictor of the in vivo apparent organic matter (in vivo dOM) and energy digestibility (in vivo dE) and digestible energy (DE) content. There was a close linear relationship between the in vivo dOM and dE [r(2) = 0.95, residual standard deviation (RSD) = 1.05 and coefficient of variation (CV) = 1.2%] and also between the in vitro and in vivo dOM (r(2) = 0.92, RSD = 1.38 and CV = 1.6%), even if the in vitro dOM overestimated on average by 4% the in vivo dOM. When the in vitro dOM was used to predict the in vivo dE, the relationship between both variables was defined by the equation: in vivo dE (%) = -2.45 + 0.98 +/- 0.04x in vitro dOM (%), (r(2) = 0.92, RSD = 1.25 and CV = 1.5%). In addition, a close relationship between the in vivo and predicted DE (estimated dE x gross energy determined calorimetrically) was found (r(2) = 0.97, RSD = 0.26 and CV = 1.4%). The accuracy of DE content prediction using the proposed in vitro method was higher than that obtained when the DE content of the same set of samples was predicted by the equation proposed by the NRC (1985) (r(2) = 0.76, CV = 4.5%) and also slightly higher than that obtained when using the equation proposed by NRC (2006) (r(2) = 0.95, CV = 2.1%).  相似文献   

15.
Giant anteaters (Myrmecophaga tridactyla) are among those mammals for which a particularly low metabolism has been reported. In order to verify presumably low requirements for energy, we used eight anteaters (two males, six females; aged 1-14 years; body mass between 46 and 64 kg) in a total of 64 individual trials, in which a variety of intake levels was achieved on various diets. Digestible energy (DE) intake was quantified by measuring food intake and faecal excretion and analysing representative samples for gross energy, and animals were weighed regularly. Maintenance DE requirements were calculated by regression analysis for the DE intake that corresponded to zero weight change. Differences between individuals were significant. Older anteaters (n = 3 animals aged 12-15 years in 29 trials) had lower relative requirements than younger ones (n = 5 animals aged 1-7 years in 35 trials); thus, giant anteaters resemble other mammals in which similar age-specific differences in energy requirements are known. However, estimated maintenance requirements were 347 kJ DE/kg(0.75)/day in the anteaters, which is low compared to the 460-580 kJ DE/kg(0.75)/day maintenance requirements of domestic dogs. The lack of knowledge that metabolic requirements are below the mammalian average could make species particularly susceptible to overfeeding, if amounts considered adequate for average mammals were provided. Non-scientific reports on comparatively fast growth rates and high body masses in captive giant anteaters as compared to free-ranging animals suggest that body mass development and feeding regimes in captivity should be further assessed.  相似文献   

16.
用32只400日龄海兰褐父母代种公鸡来研究鸡内源排泄物中内源氮损失量与内源能排出量的相关性。结果为:鸡内源氮损失量和内源能排出量之间呈现出强相关关系,相关系数r=0.97(P<0.01),二者的直线回归方程为:y^=21.02+36.21x,回归系数b=36.2KJ/g。表明内源排泄物中代谢粪氮的能值与尿的能值不同,粪中氮的能值高于尿中氮的能值。用内源排泄物中氮的能值代替尿的能值进行代谢能的校正更为合理。  相似文献   

17.
Consumers are concerned with fat consumption from meat products, and the ability to determine fat has changed with recent technological advances. The objective of this study was to predict fat percentage within marbling scores and compare 3 fat analysis procedures. Steaks (n = 119) were selected by USDA grading system using an E + V Vision Grading camera at a commercial beef plant during 1 d. Two samples per carcass were cut from the 13th rib, both sides, and transported to the University of Missouri meat laboratory. The sample from the right side of the carcass was allotted to Warner-Bratzler shear force, and the sample from the left side, which was graded by the camera, was allotted to fat extraction. Warner-Bratzler shear force samples were cut into 2.54-cm steaks and aged for 14 d. Steaks allotted to fat extraction were trimmed of all external fat and twice ground using 8- and 4-mm grinding plates. The finely ground beef was then split into its allotted fat-extraction methods. The 3 methods used in fat extraction were 2:1 chloroform/methanol (Folch), ether-extractable fat (ether), and microwave drying and nuclear magnetic resonance (CEM). Warner-Bratzler shear force values were not different between marbling scores (P > 0.05). Regardless of fat extraction method, fat percentage increased as marbling score increased (P < 0.05). All regression equations for fat percentage, regardless of extraction method, were linear. Prediction equation for fat percentage using CEM was -3.46 + 0.016 (marbling score), R(2) of 0.824 (P < 0.0001). Prediction equation for fat percentage using ether was -3.08 + 0.017 (marbling score), R(2) of 0.859 (P < 0.0001). Prediction equation for fat percentage using Folch was -3.42 + 0.019 (marbling score), R(2) of 0.816 (P < 0.0001). When the CEM, Folch, and ether methods were compared, CEM and Folch regression lines had different slopes (P < 0.05). The slope of the regression line for ether was not different (P > 0.05) from CEM or Folch. Overall, ether is the most accurate method based on the R(2) value, but CEM is environmentally safe and the fastest method for determining total crude fat percentage.  相似文献   

18.
Understanding the utilization of feed energy is essential for precision feeding in beef cattle production. We aimed to assess whether predicting the metabolizable energy (ME) to digestible energy (DE) ratio (MDR), rather than a prediction of ME with DE, is feasible and to develop a model equation to predict MDR in beef cattle. We constructed a literature database based on published data. A meta-analysis was conducted with 306 means from 69 studies containing both dietary DE and ME concentrations measured by calorimetry to test whether exclusion of the y-intercept is adequate in the linear relationship between DE and ME. A random coefficient model with study as the random variable was used to develop equations to predict MDR in growing and finishing beef cattle. Routinely measured or calculated variables in the field (body weight, age, daily gain, intake, and dietary nutrient components) were chosen as explanatory variables. The developed equations were evaluated with other published equations. The no-intercept linear equation was found to represent the relationship between DE and ME more appropriately than the equation with a y-intercept. The y-intercept (−0.025 ± 0.0525) was not different from 0 (P = 0.638), and Akaike and Bayesian information criteria of the no-intercept model were smaller than those with the y-intercept. Within our growing and finishing cattle data, the animal’s physiological stage was not a significant variable affecting MDR after accounting for the study effect (P = 0.213). The mean (±SE) of MDR was 0.849 (±0.0063). The best equation for predicting MDR (n = 106 from 28 studies) was 0.9410 ( ± 0.02160) +0.0042 ( ± 0.00186) × DMI (kg) – 0.0017 ( ± 0.00024) × NDF(% DM) – 0.0022 ( ± 0.00084) × CP(% DM). We also presented a model with a positive coefficient for the ether extract (n = 80 from 22 studies). When using these equations, the observed ME was predicted with high precision (R2 = 0.92). The model accuracy was also high, as shown by the high concordance correlation coefficient (>0.95) and small root mean square error of prediction (RMSEP), <5% of the observed mean. Moreover, a significant portion of the RMSEP was due to random bias (> 93%), without mean or slope bias (P > 0.05). We concluded that dietary ME in beef cattle could be accurately estimated from dietary DE and its conversion factor, MDR, predicted by the dry matter intake and concentration of several dietary nutrients, using the 2 equations developed in this study.  相似文献   

19.
Metabolizable energy and N-corrected ME (MEn) values of 12 samples of meat and bone meal (MBM) were determined using 288 barrows with an average BW of 35 +/- 3.1 kg. For each of 12 MBM samples, diets were formulated by substituting 0, 50, or 100 g/kg MBM (as-fed basis) in a basal 170 g of CP/kg corn-soybean meal diet; corn and soybean meal were adjusted at the same ratio to account for the substitution. Each diet was fed to eight barrows in individual metabolism crates in metabolism studies that used a 5-d acclimation, which was followed by a 5-d period of total, but separate, collection of feces and urine. The GE, CP, crude fat (CF), ash, Ca, and P contents of the MBM samples, per kilogram (DM basis), ranged from 3,493 to 4,732 kcal, 496.7 to 619.1 g, 91.1 to 151.2 g, 200.3 to 381.9 g, 54.3 to 145.8 g, and 25.6 to 61.7 g, respectively. For each of the 12 MBM samples, MBM intake and MBM contribution to ME and MEn increased linearly (P < 0.05) with increasing level of MBM in the diets. The ME and MEn content of each of the MBM samples was calculated from the slope of the regression of MBM contribution (in kilocalories) to ME and MEn intake, respectively, against quantity (in kilograms) of MBM intake. The ME and MEn of the 12 MBM samples ranged from 1,569 to 3,308 kcal/kg DM and 1,474 to 3,361 kcal/kg DM, respectively. The variation in ME was described by the regression equation: ME = 6,982 + 0.283 GE (kcal/kg) - 6.26 CP (g/kg) - 3.75 CF (g/kg) + 129.47 P (g/kg) - 54.91 Ca (g/kg) - 6.57 ash (g/kg), with an R2 of 0.612 and SD of 376. For MEn, the corresponding equation was: MEn = 3,937 + 1.089 GE (kcal/kg) - 8.74 CP (g/kg) + 3.58 CF (g/kg) + 60.89 P (g/kg) - 15.92 Ca (g/kg) - 9.57 ash (g/kg), with an R2 of 0.811 and SD of 314. Simpler regression equations describing variation in ME or MEn were 9,254 - 7.41 CP (g/kg) - 9.41 ash (g/kg), with R2 of 0.504 and SD of 278; or 12,504 - 10.71 CP (g/kg) - 13.44 ash (g/kg), with R2 of 0.723 and SD of 249. Pearson correlation analysis indicated that the variations in ME and MEn of the MBM samples were not related to any of the major chemical components. The results indicated that variation in each of the chemical components of MBM alone is not the sole determinant of ME or MEn content of MBM, but that the interactions among these components influence energy use in MBM for pigs.  相似文献   

20.
本试验旨在研究饲粮能量水平对育成期崂山奶山羊能量利用率的影响。选择体重为(18.43±0.76)kg的崂山奶山羊育成母羊30只,采用单因素随机分组设计分成3组,每组10个重复,每重复1只羊。分别饲喂粗蛋白质、钙及磷水平基本一致,消化能水平分别为10.40、11.47及12.51 MJ/kg的3种全混合日粮。预试期10 d,正试期90 d。结果表明:1)试验后期3组试羊随着饲粮能量水平的提高,总能消化率依次提高,12.51 MJ/kg组试羊的总能消化率、总能代谢率及消化能代谢率显著高于10.40 MJ/kg组(P0.05);3组试羊的总能、粪能及尿能间呈显著差异(P0.05),10.40 MJ/kg组11.47 MJ/kg组12.51 MJ/kg组;10.40 MJ/kg组试羊的甲烷能显著低于11.47及12.51 MJ/kg组(P0.05)。2)10.40 MJ/kg组试羊末重及平均日增重显著低于11.47及12.51 MJ/kg组(P0.05),但11.47 MJ/kg组与12.51 MJ/kg组间无显著差异(P0.05)。3)育成期崂山奶山羊消化能和代谢能需要量与代谢体重和平均日增重关系的回归公式:DE=0.675W~(0.75)+0.110ADG(P=0.006,R~2=0.982);ME=0.526W~(0.75)+0.076ADG(P=0.027,R~2=0.873)[式中DE为消化能(M J/d),ME为代谢能(M J/d),W~(0.75)为代谢体重(kg),ADG为平均日增重(g)]。综合得出,育成期崂山奶山羊母羊饲粮中消化能以11.47~12.51 MJ/kg(干物质基础)较为适宜。  相似文献   

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