复合酶对肉仔鸡生长后期生产性能和日粮氨基酸回肠表现消化率的影响

选取28日龄AA肉仔鸡120只,按体重对等原则分成2组,研究日粮添加复合酶对肉仔鸡生长后期生产性能和氨基酸回肠表现消化率的影响.结果表明复合酶使肉仔鸡日增重提高了5.34%,料肉比降低了3.47%,但采食量增加不显著;复合酶提高了日粮所有必需氨基酸和绝大多数非必需氨基酸的回肠表观消化率,但仅赖氨酸、缬氨酸、组氨酸、甘氨酸和胱氨酸的消化率差异显著,分别提高了9.70%,11.61%,7.60%,8.19%和9.81%.此外,复合酶还显著提高了蛋白质的回肠表观消化率.     

复合酶对肉仔鸡生长后期生产性能和日粮氨基酸回肠表现消？…

选取２８日龄ＡＡ肉仔鸡１２０只,按体重对等原则分成２组,研究日粮添加复合酶对肉仔鸡生长期生产性能和氨基酸回肠表现消化率的影响。结果表明：复合酶使肉仔对外开放日增重提高了５．３４％,料肉比降低３．４７％,但采食量增加不显著;复合酶提高了日粮所有必需氨基酸和绝大多数非必需氨基酸的回肠表观消化率,但仅赖氨酸、缬氨酸,组氨酸,甘氨酸和胱氨酸的消化率差异显著,分别提高了９．７０％,１１．６１％,７．６０％,     

免疫应激对不同品种猪氨基酸消化率的影响

本试验通过注射大肠杆菌脂多糖（LPS）构建免疫应激模型,旨在探讨免疫应激对不同品种猪氨基酸消化率的影响。分别选用6头体重为32±3.6 kg莱芜猪、鲁莱猪和大约克夏猪,采用2×3因子设计（免疫应激*品种类型）,实施回肠末端T型瘘管手术。试验猪单栏饲养,术后经过14 d适应期,进行氨基酸代谢试验。结果表明：在所测定的16种氨基酸中,除了半胱氨酸和组氨酸,免疫应激降低了不同品种猪的氨基酸的回肠表观消化率（P < 0.01）（P < 0.05）;大约克猪对总氨基酸的回肠表观消化率的降低量高于鲁莱猪和莱芜猪（P < 0.05）。     

皖麦38添加木聚糖酶对鸡表观代谢能值和氨基酸表观消化率的影响

用32只小公鸡进行代谢试验，研究高戊聚糖含量小麦品种皖麦38添加木聚糖酶对鸡表观代谢能值（AME）和氨基酸表观消化率的影响。结果显示，木聚糖酶使鸡的表观代谢能值（干物质基础）提高4．14％（P＜0．05），干物质消化率提高5．98％（P＜0．05），有机物消化率提高5．36％（P＜0．05），粗脂肪消化率提高3．01％（P＞0．05）。氨基酸表观消化率分析表明，木聚糖酶对赖氨酸和天冬氨酸的消化率分别提高5．19％（P＞0．05）和5．00％（P＞0．05）；组氨酸和脯氨酸的消化率分别提高3．67％（P＜0．05）和2．39％（P＜0．05）；亮氨酸、精氨酸、缬氨酸、丙氨酸、胱氨酸的消化率分别提高2．12％－4．18％不等；对其它氨基酸的消化率没有明显影响。     

优化测定表观消化率指示剂二氧化钛含量前处理方法的研究

旨在解决测定指示剂二氧化钛前处理方法描述不详细、测定结果变异系数大的问题，实现快速准确测定饲料中二氧化钛含量，以准确测定畜禽消化试验消化率，进而准确评定饲料品质。试验以秸秆饲料为研究对象，电感耦合等离子体发射光谱仪为检测仪器，优化了电热板硫酸消解法中硫酸铵用量与升温程序等条件，建立了硫酸消解-电感耦合等离子体发射光谱仪检测饲料中二氧化钛含量的方法；并比较了电热板硫酸消解、氢氟酸消解及干灰化3种前处理方法。结果表明，电热板硫酸消解法检测结果的精密度、回收率均优于氢氟酸消解法和灰化法，且钛在0～200 mg/L检测范围内，线性关系良好，相关系数为1.00；变异系数不大于1.32%；二氧化钛回收率大于97.1%。该方法简便、快捷，具有较宽的线性范围、较高的准确度和精密度，适用于消化试验中指示剂二氧化钛含量的批量测定，可为快速准确地测定养分表观消化率及评定饲料品质提供技术支撑。     

生长猪对菜粕和豆粕中磷真消化率的研究

选用6头健康大白×长白阉公猪为消化试验动物,采用6×6拉丁方设计,设6个磷水平(0.11%,0.22%,0.33%,0.44%,0.55%,0.53%),以豆粕、葡萄糖、玉米淀粉等为基础,以菜粕为待测植物性饲料,配制半纯合试验饲粮,其中菜粕和豆粕为磷唯一来源。日粮中添加0.35%Cr2O3作为外源指示剂。分6个试验期(每期8 d,6 d适应期,2d收粪期),测定了生长猪内源磷排泄量及菜粕和豆粕磷的真消化率。结果表明:生长猪内源磷的排泄量为0.210 8g/kg DMI,菜粕、豆粕及6个半纯合饲粮中磷表观消化率分别为-0.30%,25.77%,7.25%,16.29%,16.54%,23.62%,15.04%,28.97%,而其真消化率分别为10.21%,32.94%,26.22%,23.62%,22.95%,23.57%,22.81%,32.94%。说明饲料磷真消化率更能反映动物对饲料磷消化吸收的真实情况,具有相对较好的重演性。     

家禽内源氨基酸测定的研究进展

氨基酸的真消化率是评价饲料营养价值和可利用性的一项重要指标,一般是从表观消化率经内源氨基酸矫正获得,但是内源性氨基酸排泄量测定方面仍是争议最多的地方.同时,它也是析因法评价动物蛋白质和氨基酸需要量的重要参数,因此必须对内源氨基酸的排泄量进行准确的估测.笔者主要从家禽内源氨基酸排泄的测定方法、家禽内源氨基酸测定中存在的问题等方面作一概述.     

日粮蛋白质和淀粉水平对肉牛日粮淀粉瘤胃发酵和小肠表观消化的影响

摘要:为了研究日粮蛋白质和淀粉水平对肉牛日粮淀粉瘤胃发酵和小肠消化的影响,试验选择体重650 kg 左右,安装有瘤胃、真胃瘘管的荷斯坦（Holstein）公牛4 头,按4×4拉丁方实验设计分别饲喂精粗比和进食量相同的4 种蛋白质和淀粉水平日粮,以三氧化二铬（Cr2O3）作真胃食糜标记物,全收粪法收集粪样,测定真胃食糜和粪便中的淀粉流量及在瘤胃内、真胃后段消化道（简称肠道）内的表观消化率。结果表明日粮蛋白质和淀粉水平对瘤胃淀粉发酵率和全消化道的淀粉表观消化率没有显著影响(p>0.05),瘤胃淀粉发酵率和全消化道淀粉的表观消化率分别为83.5%和97.4%,日粮淀粉水平明显影响瘤胃发酵和小肠消化的淀粉量(p<0.05),并随淀粉进食量减少而下降(p<0.05)。     

日粮不同赖氨酸水平对生长猪养分表观消化率、血清氨基酸含量和生化指标的影响

研究日粮中不同赖氨酸水平对生长猪养分表观消化率、血清氨基酸含量和血清生化指标的影响.试验采用全收粪法进行,选用12头始重约为20 kg的长×大二元杂交阉公猪,按体重随机分为3个处理组,处理Ⅰ饲喂含赖氨酸0.65%的基础日粮,处理Ⅱ和处理Ⅲ在基础日粮中添加晶体赖氨酸盐酸盐,使赖氨酸含量分别为0.95%和1.25%,试验期为10 d.结果表明,该试验条件下,适宜的赖氨酸含量(处理Ⅱ组)使猪日粮养分表观消化率达到较好的水平,而降低赖氮酸含量(处理Ⅰ组)会使日粮能量、干物质、粗蛋白和磷的表观消化率显著降低(P<0.05);而降低或升高日粮赖氨酸水平会显著影响血清中丝氨酸(Ser)、谷氨酸(Clu)、苏氨酸(Thr)、半胱氨酸(Cys)、酪氨酸(Tyr)和赖氨酸(Lys)的含量(P<0.05或P<0.01);同时,处理Ⅰ组血清中血清尿素氮(BUN)和血清总蛋白(TP)的含量分别显著高于和低于处理Ⅱ组和处理Ⅲ组(P<0.05),但日粮不同赖氨酸水平对血清中血糖(GLU)、甘油三酯(TG)的含量无显著影响(P>0.05).结果表明,在本试验条件下,20～35 kg生长猪日粮总赖氨酸建议需要量为0.95%.     

复方中草药添加剂对仔猪饲料代谢动力学的研究

通过消化与饲养实验,研究中草药添加剂对仔猪的促生长作用机理。消化实验采用外源指示剂法,按照4×4完全拉丁方设计,用8头平均体重为9.65±1.26kg的35日龄杜长大三元杂交公猪进行了35天试验(其中预试期7天);饲养实验利用40日龄胎次相近、平均初重为10.19±1.86kg的断奶杜长大三元杂交仔猪5窝36头按照单因子随机区组设计,在经过28天的试验后结束时进行了空腹血液指标分析测定。试验得出的主要结论有:①中草药添加剂显著提高了断奶仔猪对饲料粗蛋白(CP)和酸性洗涤纤维(ADF)的表观消化率(P<0.05);中草药1组在提高饲料CP与ADF消化方面分别比喹乙醇组高14.68%、38%;②中草药添加剂显著提高了仔猪血液血小板数(PLT)(P<0.05);③中草药添加剂组比喹乙醇组显著降低了仔猪血液谷丙转氨酶(ALT)的浓度(P<0.05),提高了血液葡萄糖(Glu)的浓度(P<0.05),中草药添加剂的安全性需要重新评估。④中草药添加剂提高了血液总蛋白(TP)、白蛋白(Alb)、血清尿素氮(BUN)、谷草转氨酶(AST)、乳酸脱氢酶(LDH)和肌酸激酶(CK)的含量,差异不显著(P>0.05)。结果:复方中草药添加剂通过提高仔猪对饲料粗蛋白质与酸性洗涤纤维的表观消化率、增强蛋白质与葡萄糖的吸收、加快糖类在体内的代谢,达到对仔猪促生长作用的效果;中草药添加剂在猪饲料中的安全使用需要进一步深入研究。     

Genotypic variation for in vitro criteria and relationships with in vivo digestibility in forage maize hybrids

The aim of this work was to study the genotypic variation for in vitro digestibility and composition traits within maize elite hybrids, and their relationships with in vivo digestibility traits. Experiments using 58 maize hybrids were carried out in four French environments in 1995. Near-infrared reflectance spectroscopy (NIRS) was used to determine in vitro digestibility (whole-plant and cell-wall digestibility) and biochemical composition (starch, soluble carbohydrates, neutral detergent fibre, acid detergent lignin, protein and ash contents). The 58 hybrids were also studied at INRA, Lusignan, France, within a long-term experiment to determine their in vivo digestibility of organic matter and of crude fibre using standard sheep. Genotypic variation was studied and relationships between hybrid mean values for in vitro parameters and in vivo digestibilities were examined. For evaluation and breeding purposes, it is possible to discriminate maize elite hybrids according to their digestibility, especially for discarding low-value genotypes. in vitro parameters, such as in vitro whole-plant digestibility and cell-wall digestibility associated with cell-wall content, can be routinely investigated with NIRS. Accurate criteria that are satisfactorily relevant to reference data of in vivo digestibility evaluated with standard sheep can be obtained to explain about 60% of the variation.     

多花黑麦草在生长兔上的营养价值评定

为评定多花黑麦草在生长兔上的营养价值,研究以福建黄兔为对象,对2 个多花黑麦草品种采用全粪收集法进行消化试验。结果表明：福建黄兔生长兔对多花黑麦草‘美克斯’和‘海里克斯’干物质（DM）、粗蛋白质（CP）、粗纤维（CF）、中性洗涤纤维（NDF）、酸性洗涤纤维（ADF）、粗脂肪（EE）、粗灰分（ash）、钙（Ca）、磷（P）和无氮浸出物（NFE）的表观消化率分别为：52.67%、82.68%、21.70%、26.58%、28.59%、68.37%、57.69%、71.64%、70.82%、64.38%和50.45%、79.53%、24.69%、30.45%、32.69%、69.84%、59.38%、70.48%、69.31%、69.30%。其中生长兔对多花黑麦草DM、CP、EE、Ca 和P 的表观消化率较高,对CF的表观消化率较低。     

Genetic variation and selection criterion for digestibility traits of forage maize

Summary Variations in feeding value characteristics were studied on a factorial mating design, within a multilocal network. The in vitro digestibility of dry matter (IVDDM), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), starch, soluble carbohydrate, protein and ash contents were evaluated on whole plant samples. The in vitro digestibility of the non-starch and non-soluble carbohydrate plant part (IVDNSC) was also computed from near infra-red reflectance spectroscopy estimations of IVDDM, starch and soluble carbohydrate contents. Variations due to general combining ability (GCA) were more important, for all traits, than variations due to specific combining ability (SCA). Variations due to the GCA × environment interaction were also sizeable and were partly explained by the earliness of the lines. IVDDM was primarily influenced by the relative proportions of cell walls and starch in the whole plant, which were particularly susceptible to the development stage of the plants, at harvest. When adjusted for earliness, there was generally no significant relation between the line per se value and GCA performance in the biochemical constituent contents of the plant. On the contrary, IVDNSC seemed to be a feeding value trait worth evaluating at the inbred line level. It was also almost independent of the ripening stage and could be easily computed from whole plant samples. IVDNSC, with a simultaneous control of starch content, might be a good selection criterion for evaluating and improving the nutritive value of forage maize.     

Characterization of kafirin composition and in vitro digestibility in CMS‐lines,fertility restorers and F1 hybrids with the new types of CMS‐inducing cytoplasms of sorghum

One of the reasons of poor nutritive value of sorghum grain is resistance of its seed storage proteins (kafirins) to protease digestion. To reveal sorghum entries with increased kafirin digestibility, the sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS‐PAGE) of endosperm proteins of 10 lines [cytoplasmic male sterility (CMS)‐lines and fertility restorers] and five F₁ hybrids before and after pepsin digestion was carried out. For quantitative estimation of kafirin digestibility the SDS‐PAGE banding patterns were scanned by laser densitometer. Significant variability for both individual fractions and total kafirin digestibility was found. The line KVV‐45, fertility restorer for the Indian ‘M35‐1A’ type of CMS, had the highest level of kafirin digestibility (30% and 25% of undigested γ‐ and α₁‐kafirins, respectively), while in some entries 80–90% of kafirins remained undigested. Increased α₁‐kafirin digestibility coincided with relatively high γ‐kafirin digestibility. High‐molecular weight kafirins (HMWK) (45 kDa and 66 kDa) resistant to pepsin digestion were found in some lines, the F₁ hybrids had the same HMWK as parental lines. These data demonstrate possibility for isolation of sorghum genotypes with increased nutritive value by screening their flour for in vitro protein digestibility.     

玉米秸秆消化率全基因组关联分析

48h体外干物质消化率（48h in vitro dry matter digestibility, 48h IVDMD）是衡量青贮玉米品质的重要指标。为了初步探究玉米秸秆消化率的分子遗传机理,以341份玉米自交系为材料,于2018年在沈阳和通辽种植,收获后测定秸秆48h IVDMD。利用全基因组重测序获得的6 276 612个高质量SNPs进行全基因组关联分析,共检测到153个与玉米秸秆消化率显著相关的SNPs位点（P<1.0×10^-6）,4个SNPs显著水平在P<1.0×10^-8以上;共找到38个秸秆消化率的候选基因,主要涉及细胞生长发育、防御反应和信号转导等生物学功能。     

Variation and covariation of silage maize digestibility estimated from digestion trials with sheep

Summary Variation and covariation for agronomic and digestibility traits of silage maize are reported from a compilation of 22 years of experiments with standard sheep. Genotype effects of DOM and DCF were highly significant, even when genotypes were nested in earliness groups or brown-midrib hybrids discarded (Table 2). The genetic variance of crude fiber content was low, but the variance of the DCF was high. The genetic variance of DOM was about 4 times lower than genetic variance of DCF, but broad sense heritability of DOM was higher because of lower residual variance (Table 3). Genetic correlations between grain or crude fiber content and DOM had similar absolute values, 0.65, so each of these two traits was an important but not the unique determinant of silage maize quality. There was no correlation between DCF and grain or crude fiber content. Yield was not related to DOM or DCF within each group of earliness, allowing some quality improvement without agronomic drift (Table 4). Except for late hybrids, most of DOM differences between groups of earliness came from lowering of minimum value, while maximum values were similar. It was the contrary for DCF, with similar minimum values for all groups (Table 5). There was no obvious correlation between year of registration of hybrids and DOM or DCF, but extra new variation seemed obtained only for low values (Figs 1, 2; Table 6). IVDOM according to the APC process was a poor predictor of DOM, especially when brown-midrib hybrids and earliness effects were discarded; but because heritability of this trait was similar to DOM heritability, such enzymatic processes could probably be used to avoid drift towards poor DOM with hybrids bred for higher stalk strength.Abbreviations APC Amylase Pepsine Cellulase solubility - DDM sheep digestibility of dry matter - DOM sheep digestibility of organic matter - DCF sheep digestibility of crude fiber - DM dry matter - IVDCW in vitro digestibility of cell wall - IVDDM in vitro digestibility of dry matter - IVDOM in vitro digestibility of organic matter - NIRS near infra-red reflectance spectroscopy - NDF neutral detergent fiber - bm₁-brown-midrib-1 allele, bm₃-brown midrib-3 allele     

高静压处理对植物蛋白消化性的影响

植物蛋白作为传统动物蛋白的一种替代品,正逐渐引起人们的重视,但其功能及消化性需要改进。高静压技术是一种非热技术,具有多种应用,包括蛋白质的改性。本文综述了高静压技术对植物蛋白结构及消化性影响的研究,并对高静压改善植物蛋白消化性的研究方向提出了建议,以期拓展高静压技术在植物蛋白改性领域的应用。     

Genotype × environment interactions for digestibility traits in silage maize estimated from in vivo measurements with standard sheep

The aim of this work was to investigate the genotype × environment interaction for in vivo digestibility of organic matter and of crude fibre in silage maize evaluated with standard sheep experiments. In order to test the genotype × year interaction, the first experiment consisted of taking data subsets out of a 26-year experiment and evaluating in vivo digestibility traits at Lusignan (France) on numerous maize genotypes. In order to test the genotype × location interaction, the second experiment was a specific one whereby five hybrids were cropped in diverse locations and then evaluated from experiments with sheep, at Lusignan. The variation attributed to genotype × environment (either a year or a location) interaction for in vivo digestibility traits was distinctly lower than the variation due to the main genotypic effect. Therefore, the in vivo digestibility of organic matter and of crude fibre in maize genotypes could be accurately assessed from silages cropped in a simple experimental design, which included replicates, but only a small number of years or locations. This also confirmed the results obtained with in vitro digestibility traits from large multi-environmental designs which highlighted the low importance of genotype × environment interactions and contributed to the validation of in vitro criteria.