近红外光谱技术快速测定豆粕、玉米真可消化氨基酸含量的研究

本试验应用近红外光谱技术（ＮＩＲＳ）预测了豆粕、玉米中的真可消化氨基酸含量。氨基酸消化率用去盲肠公鸡作试验动物,用修正的Ｓｉｂｂａｌｄ强饲法进行测定。定标的结果表明,豆粕中除与胱氨酸有关的几个方程外,其它氨基酸的定标经检验证明具有良好的预测性能。玉米真可消化氨基酸的定标性能不如豆粕好,目前还不能进行实际的应用,但大部分氨基酸定标方程的相关系数经Ｆ检验达到极显著水平,说明用ＮＩＲＳ预测玉米真可消化氨基酸是可行的。近红外光谱技术提供了一种可用于日常测定鸡真可消化氨基酸的即时分析方法,它能够替代查书面值以及使用耗时而昂贵的体内法测定真可消化氨基酸含量。营养学家可根据真可消化氨基酸数据进行饲料配方,起到准确、及时、低投入、高产出、低污染、高效利用饲料资源的作用。     

评定蛋鸡豆粕代谢能和氨基酸可利用率的研究

本试验旨在评定罗曼蛋鸡对不同来源豆粕表观代谢能(AME)和氨基酸可利用率(AAA),并用傅里叶近红外光谱(NIRS)分析技术建立其预测模型。选择248只体重(1.60±0.10)kg、产蛋率85%的36周龄罗曼蛋鸡,按单因素完全随机设计,分为31组,每组8个重复,每个重复1只鸡。在训饲的基础上,采用全收粪法评定30种不同来源豆粕和1种基础饲粮的AME和AAA,然后用NIRS技术建立其生物效价的预测模型。结果如下:1)不同来源的30种豆粕AME在11.95~14.87 MJ/kg之间,平均值为(13.24±0.67)MJ/kg;总氨基酸可利用率(TAAA)在89.99%~94.96%之间,平均值为(93.73±1.23)%。2)豆粕AME的NIRS预测模型的校正决定系数(Rcal2)、交叉验证系数(Rcv2)、外部验证系数(Rval2)分别为99.24%、83.79%、80.73%,外部验证标准差(RMSEP)为0.22 MJ/kg;TAAA的NIRS预测模型的Rcal2、Rcv2、Rval2范围分别为94.20%~99.97%、76.38%~97.32%、61.80%~99.42%,RMSEP范围为0.06%~1.00%。结果表明:1)不同来源豆粕的AME、AAA在罗曼蛋鸡上有较大差异;2)利用NIRS分析技术可建立罗曼蛋鸡豆粕的AME、AAA预测模型,模型的Rcal2及预测的RMSEP较好。     

可消化氨基酸配方技术

一、可消化氨基酸配方的理论基础蛋白质原料是饲料原料中最贵重的物质之一,蛋白质的开销是饲料成本中最重要的部分。如何节约蛋白资源,利用可消化氨基酸平衡理论进行饲料日粮配方的设计是行之有效的方法。配合饲料中可消化氨基酸的含量及其平衡程度是影响饲料品质和效益的一个重要因素。准确地测定饲料中可消化氨基酸含量及动物可消化氨基酸的需要量是配制可消化氨基酸平衡日粮的技术关键。动物可消化氨基酸的需要量是源于理想蛋白质的概念。所谓理想蛋白质就是能够被特定动物完全     

利用可消化氨基酸配制家禽日粮技术

随着动物营养研究的不断深入,家禽蛋白质营养理论也不断得到丰富和完善。先后经历了粗蛋白质（ＣＰ）,可消化蛋白质（ＤＣＰ）、氨基酸（ＡＡ）、理想蛋白质（ＩＤ）、理想蛋白质可消化氨基酸模式（ＩＤ—ＤＡＡＰ）这一发展过程。因理想蛋白质氨基酸有效性定位于可消化必需氨基酸上,即考虑了动物对氨基酸的消化、代谢和作用,又与动物总体氨基酸需要相吻合。应当说此时动物对蛋白质的利用最佳、无效消耗最低、生产性能最好。国外如英国、法国、美国在这方面做了大量研究工作,许多研究成果已在生产中推广应用。国内近几年才陆续开展这方…     

现代肉鸡氨基酸和代谢能的需要

随着肉鸡遗传性状的改善,肉鸡氨基酸需要量不断增加。其结果是氨基酸推荐量也应该相应的提高。味之素(泰国)进行了罗氏308肉公鸡的相关试验,饲粮共分为4个氨基酸水平和2个代谢能水平。发现如果不考虑饲粮中代谢能水平,罗氏肉公鸡的氨基酸需要量至少要比最新的推荐量高10%。活体重、饲料转化率、胸肌率、腿肌率、瘦肉率以及饲料经济回报都随着饲粮中氨基酸水平的增高而呈线性提高。     

12个豆粕样品鸭代谢能值及氨基酸消化率的比较研究

本试验旨在通过研究鸭对12个豆粕样品的能量和氨基酸生物学利用率的差异,探讨豆粕原料中主要养分生物学效价的变异因素.试验采用单因素完全随机设计,以每个豆粕样品为1个处理,每个处理4个重复,每个重复3只鸭,以排空强饲法测定12个豆粕样品的代谢能值及氨基酸真消化率.结果表明,3#豆粕样品的鸭代谢能值最高,显著高于4#、8#、9#、10#、11#、12#豆粕样品的代谢能值(P<0.05).7#豆粕样品的鸭代谢能值次之,显著高于8#、11#、12#豆粕样品的代谢能值(P<0.05).在氨基酸消化率的差异上,7#、8#、9#豆粕样品的总氨基酸真消化率显著高于1#、2#、3#、4#、5#、12#豆粕样品(P<0.05).除6#、7#、8#、9#豆粕样品间、2#、3# 豆粕样品与1#、4#样品间在17种氨基酸的真消化率上无显著性差异外(P>0.05),其他样品两两间在某些氨基酸的真消化率上均存在显著性差异(P<0.05).从豆粕的化学成分与代谢能及氨基酸真消化率的相关关系看,不同来源豆粕代谢能值的差异可能与豆皮的含量有关,而氨基酸真消化率的差异可能与大豆的来源及生产工艺有关.     

鸡对活性肽蛋白代谢能值的研究

选用45只成年公鸡,应用套测法和强饲法相结合的研究手段,在日粮中添加不同水平的活性肽蛋白对鸡的表观代谢能值和真实代谢能值进行测定.研究表明:当活性肽蛋白的蛋白质含量为48.55%时,家禽日粮中添加10%活性肽蛋白,表观代谢能值为5.18MJ/kg,真实代谢能值为9.32 MJ/kg;添加15%活性肽蛋白,表观代谢能值为5.49MJ/kg,真实代谢能值为9.67 MJ/kg;添加20%活性肽蛋白,表观代谢能值为5.36MJ/kg,真实代谢能值为9.91MJ/kg.由此证明,48.55%粗蛋白质活性肽蛋白的表观代谢能值为5.35MJ/kg,真实代谢能值为9.63MJ/kg.     

净能体系和可消化氨基酸体系在养猪生产中的应用

<正>目前,畜牧业中能量饲料是成本最高的一种饲料,如何提高能量的利用率以及减少能量的浪费已成为畜牧行业中亟待解决的问题。净能体系最早应用于奶牛的日粮配制当中,在单胃动物中一直沿用着消化能和代谢能体系,但消化能和代谢能体系有高估蛋白质和纤维能值的趋势,低估了脂肪和淀粉的能值(Noblet,     

饲料原料的变异及用近红外光谱仪检测可消化氨基酸与代谢能

本文介绍了同种饲料原料不同批次间营养价值的差异及实测饲料代谢能和可消化氨基酸的程序、近红外(NIRS)数据库及标准曲线的建立、NIRS快速测定值与实际动物体内试验测定值的比较等内容。     

Additivity and associative effects of metabolizable energy and amino acid digestibility of corn,soybean meal,and wheat red dog for White Pekin ducks

The additivity of true amino acid digestibility (TAAD) and true metabolizable energy (TME) values in corn, soybean meal, and wheat red dog for White Pekin ducks was investigated. Differences between observed values for the complete diets and values predicted from measurements of individual ingredients were used to test additivity. Eight ducks were each assigned to the following dietary treatments: corn, soybean meal (44% CP), wheat red dog (wheat by-product with less than 4% fiber), complete Diet 1 (corn-soybean meal), complete Diet 2 (corn-red dog-soybean meal), and dextrose. Dextrose-fed ducks were used to estimate endogenous losses. The nitrogen-corrected TME (TMEn) in corn, soybean meal, wheat red dog, and two complete diets were 3.411, 2.919, 2.502, 3.148, and 3.111 kcal/g, respectively. In general, the TME and TMEn values observed in the two complete diets were not different (P > 0.05) from predicted values and indicated that the TME and TMEn in corn, soybean meal, and wheat red dog were all additive. The mean TAAD of corn, soybean meal, wheat red dog, and the two complete diets were not different, and were 87.03, 88.15, 90.58, 85.83, and 87.02%, respectively. The differences in TAAD between observed and predicted values were significant (P < 0.05) only for arginine, lysine, and aspartate in complete Diet 1, and for arginine, histidine, lysine, and aspartate in complete Diet 2. These results indicated that TME and TMEn values for corn,soybean meal, and wheat red dog were all additive in the two complete diets, but digestibilities of some amino acids were not additive and demonstrated some associative effects.     

Effect of soybean meal particle size on amino acid and energy digestibility in grower-finisher swine

A study was conducted using the ileal digestibility technique with grower-finisher pigs to evaluate the effects of particle size reduction of soybean meal (SBM) on amino acid and energy digestibility. Soybean meal was processed through a hammer mill to achieve average particle sizes of 900, 600, 300, and 150 microm. The treatments included the use of two soybean meal sources and soy protein concentrate. One source of SBM was ground to four different particle sizes (i.e., 949, 600, 389, 185); a second source was a common SBM source used in other trials (i.e., 800 microm). The soy protein concentrate had an average particle size of 385 microm. A low-protein (5% casein) diet was fed to determine endogenous amino acid losses. This experiment was conducted in a 7 x 7 Latin Square design in two replicates using 14 crossbred barrows ([Landrace x Yorkshire] x Duroc) that averaged 28 kg BW and 60 d of age. Animals were surgically fitted with a T-cannula at the distal ileum. Treatment diets were fed in meal form, initially at 0.09 kg BW(0.75) and at graded increases at each subsequent period. Pigs within replicate were fed a constant quantity of their treatment diet for a 5-d adjustment period followed by a 2-d collection of ileal digesta samples. Apparent and true digestibility of amino acids was calculated by use of chromic oxide (0.5%) as an indigestible marker. Apparent digestibility of isoleucine, methionine, phenylalanine, and valine increased linearly (P < 0.05) as particle size decreased. True digestibility of isoleucine, methionine, phenylalanine, and valine increased linearly (P < 0.05) as particle size decreased. When the essential amino acids were averaged, apparent digestibility increased (P < 0.10) from 83.5% to 84.9% as particle size decreased, whereas, nonessential amino acid digestibility increased only slightly (P > 0.15). Essential amino acid true digestibility increased numerically from 91.0% to 92.4% as particle size decreased. Energy digestibility was not affected by particle size (P > 0.15). These results suggest that a reduction in particle size of soybean meal resulted in a small increase in the digestibility of its amino acids with the essential amino acids being affected more than the nonessential amino acids. The largest improvement in digestibility, however, was obtained when the particle size was reduced to 600 microm.     

Predicting corn digestible and metabolizable energy content from its chemical composition in growing pigs

Background： The nutrient composition of corn is variable. To prevent unforeseen reductions in growth performance, grading and analytical methods are used to minimize nutrient variability between calculated and analyzed values. This experiment was carried out to define the sources of variation in the energy content of corn and to develop a practical method to accurately estimate the digestible energy （DE） and metabolisable energy （ME） content of individual corn samples for growing pigs. Twenty samples were taken from each of five provinces in China （Jilin, Hebei, Shandong, Liaoning, and Henan） to obtain a range of quality. Results： The DE and ME contents of the 100 corn samples were measured in 3.5.3 ±1.92 kg growing pigs （six pigs per corn sample）. Sixty corn samples were used to build the prediction model; the remaining forty samples were used to test the suitability of these models. The chemical composition of each corn sample was determined, and the results were used to establish prediction equations for DE or ME content from chemical characteristics. The mean DE and ME content of the 100 samples were 4,053 and 3,923 kcal/kg （dry matter basis）, respectively. The physical characteristics were determined, as well, and the results indicated that the bulk weight and 1,000-kernel weight were not associated with energy content. The DE and ME values could be accurately predicted from chemical characteristics. The best fit equations were as follows： DE, kcal/kg of DM = 1062.68 ＋ （49.72 ×EE） ＋ （0.54 × GE） ＋ （9.1 ] x starch）, with R^2 = 0.62, residual standard deviation （RSD） = 48 kcal/kg, and P 〈 0.01; ME, kcal/kg of dry matter basis （DM） = 671.54 ＋ （0.89 ×DE） - （5.57 × NDF） - （191.39 ×ash）, with R^2 = 0.87, RSD = 18 kcal/kg, and P〈 0.01. Conclusion： This experiment confirms the large variation in the energy content of corn, describes the factors that influence this variation, and presents equations based on chemical measurements that may be     

Apparent ileal digestibility of amino acids and the digestible and metabolizable energy content of high-oil corn varieties and its effects on growth performance of pigs.

Two experiments were conducted to compare the nutritional value of normal and high-oil corn for pigs. The normal corn and the two varieties (high-oil corns A and B) of high-oil corn contained 4.41, 7.35 and 8.86% ether extract, on DM basis, respectively. In experiment 1, six non-littermate crossbred barrows (37.8 +/- 1.3 kg BW) were fitted with ileal T-cannulas and used in a double replicated Latin Square digestion trial. Three diets were formulated containing 96.6% of one of the three varieties of corn as the only protein source. Chromic oxide (0.4%) was added as a digestibility marker. Additional vitamins and minerals were added to meet requirements. The digestible energy concentrations for normal corn and high-oil corn A and B were 16.53, 16.99 and 17.07 MJ/kg while the metabolizable energy values were 15.82, 16.32 and 16.36 MJ/kg, on DM basis, respectively. The ileal amino acid digestibility of high-oil corn was generally higher than that of normal corn with significant differences being observed for the essential amino acids isoleucine and phenylalanine. In experiment 2, 96 pigs (8.01 +/- 0.14 kg BW) were used to evaluate four diets in a 2 x 2 factorial design conducted over a 35-day period. Corn variety (high-oil vs. normal corn) and nutrient density (high content of protein and ME vs. low content of protein and ME) were set as the two main effects. During the first 14 days, pigs fed high-oil corn diets consumed more feed and tended to get higher daily gain than pigs fed normal corn. Over the entire 35-day experiment, increasing dietary nutrient density increased daily gain and tended to increase feed conversion, while variety of corn had no significant effects on performance. Overall, the present results indicate that the energy concentration and ileal amino acid digestibility of high-oil corn varieties were equal or superior to those in normal corn and therefore they should be able to be effectively utilized in diets fed to swine.     

Effects of the standardized ileal digestible lysine to metabolizable energy ratio on performance and carcass characteristics of growing-finishing pigs

A total of 2,121 growing-finishing pigs (Duroc × Landrace × Large White) were utilized in six experiments conducted to determine the effects of different ratios of standardized ileal digestible lysine (SID-Lys) to metabolizable energy (ME) on the performance and carcass characteristics of growing-finishing pigs. Exps. 1 (30 to 50 kg), 2 (52 to 70 kg) and 3 (81 to 104 kg) were conducted to find an optimum ME level and then this level was used in Exps. 4 (29 to 47 kg), 5 (54 to 76 kg) and 6 (84 to 109 kg) to test the response of pigs to different ratios of SID-Lys:ME. In Exps.1 to 3, four treatments were used consisting of diets with a formulated ME content of 3.1, 3.2, 3.3 or 3.4 in Exps. 1 and 2 while Exp. 3 used 3.05, 3.15, 3.25 or 3.35 Mcal/kg. A constant SID-Lys:ME ratio of 2.6, 2.3 or 2.0 g/Mcal was used in Exps. 1, 2 and 3, respectively. Weight gain was significantly increased with increasing energy level in Exp.1 while weight gain was unaltered in Exps. 2 and 3. For all three experiments, feed intake was decreased (P < 0.05) and feed efficiency was improved (P < 0.05) with increasing energy level. Tenth rib back fat thickness linearly increased (P < 0.05) with increasing energy level. In Exps. 4 to 6, five treatments were used consisting of diets with a SID-Lys:ME ratio of 2.4, 2.6, 2.8, 3.0 or 3.2 in Exp. 1, 2.1, 2.3, 2.5, 2.7, 2.9 or 3.2 in Exp. 2 and 1.8, 2.0, 2.2, 2.4, or 2.6 in Exp. 3. A constant ME level 3.2, 3.2 and 3.05 Mcal/kg was used in Exps. 1, 2 and 3, respectively (selected based on the results of weight gain). For all three experiments, weight gain increased (P < 0.05) and feed efficiency improved linearly (P < 0.05) as the SID-Lys:ME ratio increased. Tenth rib back fat thickness linearly decreased (P < 0.05) as the SID-Lys:ME ratio increased. Based on a straight broken-line model, the estimated SID-Lys:ME ratio to maximize weight gain was 3.0, 2.43 and 2.2 for 29 to 47, 54 to76 and 84 to 109 kg of pigs, respectively.     

Evaluation of prediction of barley digestible nutrient content with near-infrared reflectance spectroscopy (NIRS)

Near-infrared reflectance spectroscopy (NIRS) was evaluated as a tool to predict the contents (ileal digestible) of protein (IDP), lysine (IDLys), cystine (IDCys), methionine (IDMet) and the contents (faecal digestible) of organic (DOM) and dry matter (DDM) in barley samples for pig diets. Twenty barley samples, which had previously been tested for in vivo and in vitro nutrient digestibility in pigs, were scanned. A number of NIRS calibrations were developed using the in vitro digestibility data of fifteen barley samples as a reference. Validation using the five remaining barley samples was used to select the best equations. The robustness of the calibrations was further tested by validating them with the in vivo digestibility data. Despite the limited number of samples used in the calibration, NIRS was able to accurately predict the content of IDP, IDLys, IDMet and DOM. On the other hand, DDM and IDCys contents could not be accurately predicted. Although, larger sample sets will be required to generate calibrations, which could be applied in the feed industry, these results show that NIRS is a potentially good tool to evaluate the digestible nutrient content of barley.     

Effect of apparent ileal digestible lysine to energy ratio on performance of finishing pigs at different dietary metabolizable energy levels

A study with a total of 96 crossbred barrows and gilts fed ad libitum in a body weight range of 56-110 kg was carried out in order to investigate whether the optimum ratio of apparent ileal digestible lysine : energy (ME) depends on the energy density of the diet. Dietary treatments were ratios of 0.34, 0.42, 0.50 and 0.58 g digestible lysine/MJ ME either at an energy density of 13 or 14 MJ ME. Body weight gain as well as feed and ME conversion rate were improved when lysine : ME ratio increased from 0.34 to 0.50, whereby all parameters showed a significant ratio x sex interaction. Feed intake and feed conversion rate were higher at a dietary energy density of 13 MJ ME than at an energy density of 14 MJ ME but energy density did not influence daily growth rate, ME intake and ME conversion rate. Fat area above eye muscle and meat : fat ratio were lower and eye muscle area and lean percentage were higher at a ratio of 0.42 compared with a ratio of 0.34. Daily feed intake, body weight gain, feed conversion rate and parameters of fatness were higher in barrows than in gilts. Conversely, gilts had higher eye muscle area and lean percentage. Optimum ratio for body weight gain, feed and ME conversion rate calculated by exponential regression analysis were 0.42-0.43 in barrows. In gilts, feed and ME conversion rate were optimized at a ratio of 0.53 and 0.54. Because growth showed a linear response to increasing digestible lysine : ME ratios, optimum ratio for daily gain in gilts is considered to be at least 0.58.     

大豆酶解蛋白改善断奶仔猪日粮常规成分、氨基酸和能量利用率的比较研究

为了探明大豆酶解蛋白替代仔猪饲粮中血浆蛋白粉、肠膜蛋白或鱼粉的功效。研究选择28 d断奶三元杂交(杜×长×大)仔猪320头,随机分为4个处理,每个处理4个重复,每个重复20头。分别饲喂:处理1:3%血浆蛋白+3%肠膜蛋白+3%鱼粉日粮;处理2(无血浆蛋白质):9%大豆酶解蛋白+3%肠膜蛋白+3%鱼粉日粮;处理3(无肠膜蛋白):4%大豆酶解蛋白+3%血浆蛋白+3%鱼粉日粮;处理4(无鱼粉):3.5%大豆酶解蛋白+3%血浆蛋白+3%肠膜蛋白日粮。试验猪于28 d开始饲喂各自日粮,于42～49 d,每个重复选择2只猪,用AIA法测定养分利用率(常规养分、氨基酸和总能表观消化率)。研究结果证明:以典型的3%血浆+3%肠膜+3%鱼粉日粮对比,9%大豆酶解蛋白+3%肠膜+3%鱼粉、4%大豆酶解蛋白+3%血浆+3%鱼粉和3.5%大豆酶解蛋白+3%血浆+3%肠膜组合的仔猪日粮可以获得较高的EE、CP、OM、CHO和GE表观利用率,可以使表观消化能分别提高2.2%、0.5%和1.6%(P0.05)。9%大豆酶解蛋白+3%肠膜+3%鱼粉、4%大豆酶解蛋白+3%血浆+3%鱼粉和3.5%大豆酶解蛋白+3%血浆+3%肠膜组合的仔猪日粮可以获得较高的日粮必需氨基酸(赖氨酸、蛋氨酸、色氨酸、精氨酸、组氨酸、亮氨酸、异亮氨酸、苯丙氨酸、苏氨酸和缬氨酸)和非必需氨基酸(天冬氨酸、丝氨酸、谷氨酸、甘氨酸、丙氨酸、胱氨酸、络氨酸)表观利用率。总必需氨基酸表观消化率可以分别提高0.96%、0.84%和2.74%。总非必需氨基酸表观利用率可以分别提高0.46%、0.75%和3.02%(P0.05)。由此证明,使用9%的大豆酶解蛋白可以替代日粮中3%的血浆蛋白粉,4%的大豆酶解蛋白可以替代日粮3%的肠膜蛋白质,3.5%大豆酶解蛋白可以替代日粮中3%的鱼粉。大豆酶解蛋白有提高仔猪日粮养分和能量利用率的功效。     

广西玉林地方鸡种适宜能量和蛋白质需要的研究

玉林三黄鸡属广西地方优质鸡种之一 ,本试验旨在研究其母鸡全期日粮适宜能量 (ME)和粗蛋白质 (CP)的需要水平。试验设 4 (ME)× 4(CP)共 1 6个处理 ,每个处理 4 0～ 6 0只母鸡。结果表明 :以增重和经济效益为综合衡量指标 ,0～5周龄适宜ME和CP分别为 1 2 1 3兆焦 (MJ) /千克和 2 1 % ,6～ 8周龄分别为 1 2 1 3兆焦 (MJ) /千克和 1 8% ,9～ 1 1周龄分别为 1 2 1 3兆焦(MJ) /千克和 1 5%～ 1 6 % ,1 2周龄至出栏分别为1 3 39兆焦 (MJ) /千克和 1 5%。