双低菜籽粕在饲料中的应用

双低菜籽粕具有高产优质的特点,其饲用品质优于普通菜籽粕,营养价值与豆粕相当,被广泛应用于饲料。为了更有效开发其对饲料业和养殖业的应用潜力,本文就双低菜籽粕的营养价值和在动物饲用方面进行的一系列的基础性研究作一简要介绍。     

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。     

晾晒时间和青贮时间对青贮玉米发酵品质的影响

目的 探究不同晾晒时间和青贮时间对全株青贮玉米发酵品质的影响。方法 以玉米（Zea mays L.）青贮品种“曲辰9号”为试验材料,将乳熟末期的青贮玉米全株收获粉碎后,在阴凉处分别晾晒0（对照,CK）、1、2、3、4 d,然后在塑料桶（5 L）中分别进行青贮,待青贮60、90、120 d时进行发酵品质的评定。结果 青贮玉米的含水量随着晾晒时间的增加而降低,在晾晒2、3、4 d后含水量显著（P<0.05）低于CK;用晾晒2、3、4 d的全株青贮玉米原料进行青贮,pH值显著（P<0.05）高于CK,晾晒2 d青贮120 d处理除外。晾晒时间对乳酸、丁酸、中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）含量均产生显著（P<0.05）影响,青贮时间仅对乳酸、丁酸产生显著（P<0.05）影响,其中,乳酸含量随着青贮时间的延长而增加,丁酸含量在原料晾晒之后明显增加。CK处理中,青贮90、120 d的NDF含量显著（P<0.05）高于青贮60 d处理。利用氨态氮、乙酸、丙酸、丁酸开展V-Score分析,晾晒导致青贮玉米发酵品质降低,试验中品质较优的青贮为原料粉碎后未经晾晒的处理（CK）。结论 在未经晾晒处理下进行青贮60 d的青贮玉米,综合品质较高。在青贮玉米原料含水量为74%时,不建议粉碎之后通过晾晒降低含水量再青贮。     

Processing traits and digestibility of extruded dog foods with soy protein concentrate

Soya bean protein concentrate (SPC) with two particle sizes were evaluated on extrusion parameters, kibble formation, digestibility and palatability of dog foods. Eight diets were extruded: PBM—control diet based on poultry by‐product meal (PBM); GM—a diet in which corn gluten meal (GM) replaced 45% of the diet protein; cSPC15%, cSPC30% and cSPC45%—diets in which SPC of coarse particle size (600 μm) replaced 15%, 30% and 45% of the diet protein; and sSPC15%, sSPC30% and sSPC45%—diets in which SPC of small particle size (200 μm) replaced 15%, 30% and 45% of the diet protein. The digestibility of nutrients was evaluated for the PBM, GM, cSPC45% and sSPC45% diets, using six dogs per food. The PBM, GM and cSPC45% diets were compared for palatability. Data were submitted for analysis of variance, and the means were compared by polynomial contrasts or Tukey's test (p < .05). The cSPC increased the specific mechanical energy (SME) application, extrusion temperature and pressure linearly, resulting in lower kibble density and higher expansion and starch gelatinization (SG) (p < .01). When comparing the PBM, GM, cSPC45% and sSPC45% diets, higher SME, extrusion temperature and pressure, SG and kibble expansion were verified for the cSPC45% diet (p < .05). The DM, fat and crude protein digestibility were similar among diets. Faecal pH, ammonia and lactate did not differ, demonstrating that the removal of oligosaccharides and soluble non‐starch polysaccharides of SPC produces an ingredient with mostly non‐fermentable fibre. Dogs preferred the PBM to the GM diet (p < .05), but consumed the PBM and cSPC45% foods equally. In conclusion, SPC exhibited good extrusion functionality, favouring kibble expansion and SG, with high digestibility, similar to that of PBM. The removal of soluble compounds from soya beans resulted in an ingredient with low fermentable fibre content, which did not alter faecal formation or characteristics.     

鱼精粉在肉鸡日粮中替代进口鱼粉的效果

选用ＡＡ肉鸡进行试验,试验在生产后期进行,试验分为两组：对照组（含有３％的秘鲁鱼粉）和试验组（含有３％的鱼精粉）,两组的营养水平接近。试验组平均日增重为４７．１８ｇ,对照组为４７．０６ｇ;试验组的料肉比为２．６８４,对照组为２．７４５。两者的重要生产性能指标接近,差异不显著。试验结果表明,在生长后期的肉鸡日粮中,使用鱼精粉替代进口鱼粉并不影响试验鸡的生产性能。     

NaOH与超声联合预处理玉米秸秆实验条件优化研究

试验选用超声与NaOH法对玉米秸秆进行联合预处理,通过分析预处理后秸秆还原糖含量、组分变化量、厌氧发酵产气量等参数,对预处理的条件进行优化.试验结果表明:3％ NaOH浓度,浸泡时间为48 h,超声功率为80 W,超声温度为50℃的预处理条件下,还原糖含量较高,为0.0947 g·g-1.联合试验组产气量比单一超声处理...     

紫玉米花青苷的研究进展

紫玉米花青苷作为天然食用色素不仅安全无毒,而且具有一定的生物活性。敬璞就在美国对花青苷的多年研究积累,并结合国外其他学者的研究工作,对紫玉米花青苷进行了综述,主要包括:紫玉米花青苷含量和分子结构;紫玉米花青苷的生物活性、构效关系、结构修饰、加工方法对其活性的影响;紫玉米花青苷的提取及综合利用;同时,提出该研究方向的发展趋势,以供参考。     

一年两作地区玉米直播机械化技术可行性研究

在山东一年两作的玉米播种中多年来一直沿用了麦田套种的习惯，成为机械化技术的大面积高效率应用的一个障碍。本文在总结山东省各地实践验的基础上，从机械技术的发展、玉米品种的培育和气候变迁等方面研究了实行玉米直播机械化技术的可行性，以期对于适宜地区的玉米生产提供参考。     

Effects of dietary cottonseed meal protein level on growth, gonad development and plasma sex steroid hormones of tropical fish tilapia Oreochromis sp

Five experimental diets containing increasing proportions of cottonseedmeal (CSM) protein (0, 25, 50, 75 and 100%; diets 1 to 5, respectively) toreplace fish meal (FM) protein were formulated for intensive culture of tilapiaOreochromis sp. Each diet was fed to three replicategroupsof fish (mean weight ± SE = 11.3 ± 3.9 g) in30L aquaria connected as a closed recirculating-water system andmaintained at 27 ± 1 °C. Fish were fed three times adayby hand at a rate of 3% of body weight during four weeks, after which thefeeding rate was gradually decreased to reach 1.5% at 16 weeks. Thesubstitutionof 75 and 100% of FM proteins by CSM proteins resulted in significantly lowerbody weights in both sexes. In both sexes, gonadosomatic indexes and plasmaconcentrations of sex steroids (testosterone, 11-ketotestoterone,estradiol-17 and 17,20-dihydroxy-4-pregnen-3-one) were notsignificantly different among dietary treatments. The concentration ofgossypol,an antifertility agent contained in CSM, was measured in reproductive tissues.The total gossypol concentration in the testis was consistently lower than thatmeasured in the ovaries of the same group. Moreover, in both sexes, theconcentration of the (+)isomer of gossypol was always higher than that of(–)isomer. The total gossypol concentrations in testes increasedsignificantly with the increase of CSM in the diet. The highest levels of the(+)isomer (7.64 ± 0.62 g g^–1)were found in the testes of fish fed diet 4, whereas the (–)isomerreached its highest values in the testes of fish fed diet 5. The highest levelsof both enantiomers of gossypol were found in the ovaries of fish fed diet 4(14.2 ± 2.7 and 5.6 ± 1.5 g g^–1for (+) and (–)isomers, respectively). In both sexes, thehistological analysis of the gonads did not reveal differences among the fishfed different levels of CSM. Although CSM at any levels did not affect thereproductive parameters examined in this study, it cannot be used to substitutemore than 50% of FM since at higher levels growth of tilapia was compromised.     

Effect of Natural Feed,Antibiotics, Tannin,Diphenyliodoniumchloride and Salicylic Acid Supplement on Plasma Uric Acid Concentration in Captive Willow Ptarmigan (Lagopus L. Lagopus)

Mortality due to nephritis and uric acid diathesis was observed during the fall and winter in captive willow ptarmigan. The present study examined how feed protein concentration influences feed and water consumption, plasma uric acid concentration, and mortality due to nephritis and uric acid diathesis in captive w^rillow ptarmigan. An increase in feed protein concentration from 14 to 24 % resulted in reduced feed consumption and increased plasma uric acid concentration. Mortality due to nephritis and uric acid diathesis was not influenced by variations in feed protein concentration, but an admixture of 14 % grass meal to the diet reduced the incidence markedly.