不同添加剂对籽粒苋青贮品质的影响

为探讨不同添加剂对籽粒苋青贮的影响,以结实期籽粒苋为原料,分别设计对照、添加甲酸(6 mL/kg)或蔗糖(2%)处理,袋装密封青贮60 d后取样分析。结果表明:添加蔗糖或甲酸都能显著改善籽粒苋青贮饲料的发酵品质,添加甲酸可以极显著降低青贮饲料的pH、乙酸和氨态氮含量(P<0.01)。添加蔗糖可以显著降低青贮饲料的pH(P<0.05),极显著提高乳酸含量(P<0.01),极显著降低青贮饲料的乙酸和氨态氮的含量(P<0.01)。添加甲酸籽粒苋青贮饲料的WSC含量显著高于对照(P<0.05)。与原料相比,青贮之后,硝酸盐含量显著下降,而亚硝酸盐含量增加。     

晾晒和添加剂对白羊草青贮的影响

为探究含水量和添加剂对白羊草(Bothriochloa ischaemum)青贮的影响,以抽穗期新鲜的和晾晒的白羊草为原料,分别设计对照、添加甲酸(6 mL·kg^-1)或蔗糖(2%)处理,袋装密封青贮360 d后取样分析。结果表明:晾晒处理白羊草青贮饲料的pH较高,乳酸和氨态氮含量极显著下降(P<0.01);添加蔗糖或甲酸能够改善白羊草青贮饲料的发酵品质,甲酸或蔗糖均能够极显著降低白羊草青贮饲料的pH、乙酸和氨态氮含量(P<0.01),极显著提高乳酸含量(P<0.01);添加甲酸或蔗糖显著提高了白羊草青贮饲料的干物质保存率(P<0.05);青贮之后,硝酸盐含量下降。添加剂可改善白羊草青贮饲料的发酵品质,而白羊草晾晒后再进行添加剂青贮则效果更佳。     

不同添加剂对苦荬菜青贮品质的影响

为探讨不同添加剂对2种苦荬菜青贮的影响,以结实期苦荬菜为原料,分别设计对照、添加甲酸(6 mL/kg)或蔗糖(2%)处理,袋装密封青贮60 d后取样分析。结果表明:添加甲酸或蔗糖都能显著改善苦荬菜青贮饲料的发酵品质。添加甲酸可以极显著降低青贮饲料的pH值和氨态氮含量(P<0.01),显著提高乳酸含量(P<0.05);添加蔗糖可以显著降低青贮饲料的pH值和氨态氮含量(P<0.05),显著提高乳酸含量(P<0.05)。添加甲酸苦荬菜青贮饲料的WSC(水溶性碳水化合物)含量极显著高于对照和蔗糖处理(P<0.01)。与原料相比,青贮之后硝酸盐含量显著下降,而亚硝酸盐含量增加。     

不同添加剂对苇状羊茅青贮的效果研究

为研究探讨苇状羊茅原料的青贮特性,青贮饲料发酵品质、营养物质含量,以结实期的新鲜或晾晒苇状羊茅为原料,分别设计对照、添加甲酸(6 mL/kg)或蔗糖(2%)处理,袋装密封青贮360 d后取样分析其发酵品质与养分含量。结果表明,晾晒可以显著降低苇状羊茅青贮饲料的pH和乳酸含量(P0.05),极显著降低氨态氮含量(P0.01)。添加甲酸和蔗糖都能够显著降低苇状羊茅青贮饲料的pH(P0.05),极显著降低乙酸和氨态氮含量(P0.01),极显著提高乳酸含量(P0.01)。晾晒或添加剂处理对苇状羊茅青贮饲料常规养分的影响不明显,青贮之后硝酸盐含量显著降低。苇状羊茅在单独青贮时具有调制为优质青贮饲料的特征。     

串叶松香草青贮条件的研究

为探讨串叶松香草原料的青贮特性,青贮饲料的发酵品质、营养物质的含量,以开花期的新鲜或晾晒串叶松香草为原料,分别设计对照、添加甲酸(6ml/kg)或蔗糖(2%)处理,袋装密封青贮360d后取样分析。结果表明,晾晒可以显著降低串叶松香草青贮饲料的pH值和乙酸含量(P0.05),显著提高乳酸含量(P0.05),极显著降低氨态氮含量(P0.01)。添加甲酸和蔗糖都能够极显著降低串叶松香草青贮饲料的pH值和氨态氮含量(P0.01),极显著提高乳酸含量(P0.01),显著减少乙酸含量(P0.05)。晾晒或添加剂处理对串叶松香草青贮饲料常规养分的影响不明显,青贮之后硝酸盐含量显著降低。串叶松香草在单独青贮时不具有调制为优质青贮饲料的特征。     

鹰嘴紫云英青贮的研究

为了探讨鹰嘴紫云英的青贮特性及青贮饲料的发酵品质、营养物质的含量,以始花期的新鲜或晾晒鹰嘴紫云英为原料,分别设计对照、添加甲酸(6mL/kg)或蔗糖(2%)处理,袋装密封青贮360d后取样分析.结果表明,晾晒可以显著降低鹰嘴紫云英青贮饲料的pH值和乳酸含量(P<0.05),极显著降低氨态氮含量(P<0.01).添加甲酸和蔗糖均能够极显著降低鹰嘴紫云英青贮饲料的pH值和氨态氮含量(P<0.01),显著提高乳酸含量(P<0.05),显著减少乙酸含量(P<0.05).结论:晾晒及添加甲酸或蔗糖对鹰嘴紫云英青贮饲料的NDF、ADF、Ash、EE等养分含量和干物质保存率没有显著的影响,并且对硝酸盐和亚硝酸盐含量也没有显著影响,CP含量因添加甲酸而显著增加(P<0.05).青贮之后硝酸盐含量显著降低.     

不同添加剂对谷稗青贮品质的影响

为探讨不同添加剂对谷稗青贮的影响,以结实期谷稗为原料,分别设置对照、添加甲酸(6 mL/kg)或蔗糖(2%)处理,袋装密封青贮60 d后取样分析。结果表明:青贮饲料的pH、乙酸和氨态氮含量极显著降低(P<0.01),乳酸含量显著增加(P<0.05)。水溶性碳水化合物含量和干物质保存率因添加甲酸而显著升高(P<0.05)。添加蔗糖能够极显著提高乳酸含量(P<0.01),显著降低乙酸含量(P<0.05),极显著降低氨态氮含量(P<0.01)。添加剂处理对谷稗青贮饲料其他常规养分的影响不明显,青贮之后硝酸盐含量显著降低。说明添加甲酸或蔗糖都能显著改善谷稗青贮饲料的发酵品质。     

含水量及添加剂对高冰草青贮饲料品质的影响

本试验旨在研究含水量以及添加蔗糖、甲酸对高冰草青贮饲料品质的影响,探究优质高冰草青贮饲料的调制方式。试验选用结实期间的高冰草为原料,原料含水量分为鲜贮与晾晒2个处理,添加剂设置对照、添加甲酸、添加蔗糖3个处理。不使用任何添加剂为对照,甲酸添加量为6 mL/kg,蔗糖添加量为2%,袋装青贮360 d。结果表明,高冰草青贮时,原料进行晾晒,青贮饲料的pH显著增加(P<0.05)。晾晒处理减少乳酸(P<0.05)和氨态氮(P<0.01)的生成,增加乙酸的生成(P<0.05)。添加甲酸能够极显著降低高冰草青贮饲料的pH(P<0.01),提高乳酸的生成量(P<0.01),减少乙酸的生成(P<0.05)。添加蔗糖能够显著降低高冰草青贮饲料的pH(P<0.05)和乙酸的含量(P<0.01),提高乳酸生成(P<0.01)。添加甲酸或蔗糖都能够极显著降低高冰草青贮饲料的氨态氮含量(P<0.01)。晾晒、添加甲酸或蔗糖对高冰草青贮饲料的CP、NDF、ADF、Ash、EE等养分含量和干物质保存率没有显著的影响,并且对硝酸盐和亚硝酸盐含量也没有显著影响。与原料相比,硝酸盐含量下降48%～53%,亚硝酸盐含量有所增加。     

晾晒和添加剂对菊苣青贮的影响

为研究含水量和添加剂对菊苣(Cichorium intybus L)青贮的影响,以开花期菊苣鲜样和晾晒样为原料,分别添加甲酸(6m L/kg)或蔗糖(2%)处理,袋装并密封青贮360d后取样分析。结果表明,经晾晒后制作的菊苣青贮饲料的p H较高,乙酸和氨态氮含量极显著下降(P0.01);添加甲酸或蔗糖均能够极显著降低菊苣青贮饲料的p H和氨态氮含量(P0.01),极显著提高乳酸含量(P0.01);青贮后硝酸盐含量下降。添加剂可以改善菊苣青贮饲料的发酵品质,菊苣经晾晒后再使用添加剂进行青贮效果更好。     

晾晒与添加剂对反枝苋青贮饲料品质的影响

为探究含水量及添加剂(甲酸和蔗糖)对反枝苋(Amaranthus retroflexus)青贮饲料品质的影响,以开花期的反枝苋为原料,在鲜贮和晾晒2种条件下分别设置甲酸(6 mL·kg^-1)和蔗糖(2%)处理,以不使用任何添加剂为对照,袋装青贮360 d。结果表明:晾晒处理与鲜贮的反枝苋青贮饲料pH值和乳酸含量均无显著差异,而乙酸含量极显著增加(P<0.01),氨态氮含量显著降低(P<0.05),通过青贮硝酸盐含量显著降低,青贮饲料品质无显著差异。添加甲酸和蔗糖能够改善反枝苋青贮饲料的发酵品质,极显著降低反枝苋青贮饲料的pH值和氨态氮含量并提高乳酸生成量(P<0.01)。     

Cattle grazing Wahweap milkvetch in southeastern Utah

Cattle's grazing of the locoweed Wahweap milkvetch (Astragalus lentiginosus var. wahweapensis) was evaluated on desert and foothill winter range during the winter of 1986 to 1987. Dry, dead stalks of Wahweap milkvetch that had grown in 1985 and 1986 made up 15% of cattle diets overall, and 24% of diets when cattle grazed gravelly benches where it was abundant. Nutritional quality of Wahweap milkvetch was higher than of most associated forage, but its alkaloid concentration varied among the senescent stages. One cow aborted and two cows developed clinical signs of locoweed poisoning, including water belly (hydrops amnii). Microscopic lesions consisting of cytoplasmic foamy vacuolation were evident in both the dam and fetus. Because senescent stalks of Wahweap milkvetch are palatable and readily grazed by cattle, ranchers should not permit cattle to graze infested sites until other green forage is available in the spring.     

Emory milkvetch (Astragalus emoryanus var emoryanus) poisoning in chicks, sheep, and cattle.

A severe outbreak of Emory milkvetch poisoning in cattle and sheep occurred near Roswell, New Mexico, in the spring of 1975. Mortality averaged 2% to 3% and morbidity averaged 15% to 20%. Emory milkvetch collected from the infested area contained miserotoxin measured as 5 to 9 mg of NO2/g of plant (dry weight). Chicks fed extracts of Emory milkvetch showed toxic signs when fed one dose as 300 mg of NO2/kg of body weight, and died within 5 to 8 hours when fed milkvetch as 400 mg of NO2/kg. A sheep fed Emory milkvetch for 7 days in the form of 38 mg of NO2/kg/day developed signs of nitro poisoning on the 7th day. Cattle were poisoned or died when fed Emory milkvetch as 12 to 20 mg of NO2/ig for several days. The toxic signs observed in the field and under experimental conditions were similar.     

Effects of forage source on ruminal microbial nitrogen metabolism and carbohydrate digestion in continuous culture

Eight single-flow, continuous culture fermentors were used in Exp. 1 to study the effects of forage source on ruminal bacterial N metabolism and carbohydrate digestion. Forages included alfalfa, cicer milkvetch, birdsfoot trefoil and sainfoin with respective CP concentrations of 26.0, 28.7, 26.3 and 20.0%. Each forage provided 100% of the substrate for microbial metabolism and supplied 2.6 g N/d. Ammonia-N, protein degradation and efficiency of ruminal bacterial protein synthesis were lowest (P less than .05) for sainfoin. Protein degradation and efficiency of bacterial protein synthesis were higher (P less than .05) for birdsfoot trefoil than for alfalfa. Effluent flow of amino acids was highest (P less than .05) for sainfoin. Total nonstructural carbohydrate digestion tended to be highest for sainfoin and birdsfoot trefoil, whereas structural carbohydrate digestion was highest (P less than .05) for alfalfa and cicer milkvetch. In Exp. 2, mixed diets were supplied to dual-flow, continuous culture fermentors with alfalfa, cicer milkvetch, birdsfoot trefoil and sainfoin contributing 85% of the total dietary CP. Each diet contained approximately 12.9% CP. Ammonia-N concentration in the effluent and CP degradation tended to be lowest with the sainfoin diet and highest with the birdsfoot trefoil diet. Effluent flow of amino acids tended to be highest with the cicer milkvetch diet and lowest with the alfalfa and birdsfoot trefoil diet. Total structural and nonstructural carbohydrate digestion was not different (P greater than .05) among forages. Results from these experiments indicate that bacterial degradation of protein was lower for sainfoin than for alfalfa. Birdsfoot trefoil and cicer milkvetch appear to be comparable to alfalfa with regard to metabolism of N and carbohydrates by ruminal bacteria.     

不同添加剂对沙打旺青贮饲料发酵品质和化学成分的影响

本试验以沙打旺为原料,通过添加LaLsIL Dry(LD)、SiloGuard(SG)和Mieromanger H/M(MH)等添加剂,分析了这些添加剂对沙打旺青贮品质的影响.试验设置对照(CK)、LD处理(0.000 5%、0.001%、0.001 5%、0.002%、0.004%)、SG处理(0.05%、0.1%、0.15%、0.2%、0.4%)和MH处理(0.001%、0.002%、0.03%、0.04%)15个处理,每个处理3个重复,青贮90 d后打开青贮袋,分析青贮饲料的发酵品质和化学成分.结果表明:沙打旺直接青贮其发酵品质较差;LD处理青贮饲料的非蛋白占总氮的比例(NPN/TN)、氨态氮占总氮比例(AN/TN)和丁酸含量显著低于对照组(P<0.05),LD1(0.000 5%)和LD2(0.001%)处理的pH达到了4.2以下,并且乳酸含量显著高于对照组和LD其它添加水平组(P<0.05),LD处理改善了青贮饲料的发酵品质,LD2(0.001%)处理添加效果最好;SG处理的青贮饲料pH除SGS(0.4%)处理组以外均高于对照组(P<0.05),乳酸和丁酸含量较低,氨态氮占总氮比例显著高于对照(P<0.05);MH处理的青贮饲料pH、非蛋白氮占总氮比例(NPN/TN)和丁酸含量较低,乳酸和总酸含量显著高于对照组(P<0.05),MH处理的沙打旺青贮饲料的发酵品质得到了明显的改善.     

紫云英腐解液对牛筋草种子萌发及幼苗生长的影响

为探讨不同腐解天数及不同浓度梯度紫云英的腐解液对牛筋草种子萌发及二叶期幼苗生长的影响,以牛筋草种子为材料进行发芽试验,测定发芽率等6个生理指标。采用不同浓度的紫云英腐解液对二叶期幼苗进行灌根处理,测定牛筋草叶片的保护酶活性、脯氨酸（Pro）和丙二醛（MDA）含量。结果表明：相同浓度腐解液处理条件下,随着腐解天数的增加,腐解液对牛筋草的抑制作用增强;腐解液对牛筋草的化感作用存在“低促高抑”的现象;当腐解时间超过2 d,腐解液处理浓度达到80%时,能100%抑制牛筋草种子萌发。牛筋草幼苗的超氧化物歧化酶（SOD）活性随着腐解液浓度升高而下降;过氧化物酶（POD）在低浓度腐解液处理时酶活性下降,浓度大于30%时酶活性升高;过氧化氢酶（CAT）活性在30%腐解液浓度内随着浓度升高而升高,80%时活性下降。当腐解液浓度≥2%时,随着腐解液浓度的增加,牛筋草叶片MDA、Pro及过氧化氢（H₂O₂）含量增加。综上所述,紫云英腐解液对牛筋草种子萌发及幼苗生长具有显著的抑制作用。由此可见,紫云英腐解物具有抑制杂草生长的潜力,研究结果可为发掘紫云英中抗杂草活性物质提供参考。     

一种适合稻区紫云英生产实际的紫云英加工调制方式

将紫云英鲜草分离为草汁、细渣、纤维状渣；以粉状能量精料为载体吸收汁液；3种制品都以晾晒的方式进行干燥。晾晒时，3种制品综合占场面积较原草减少近90％；3种制品均可在一个晴日内风干，比原草干燥速度提高一倍余；细渣品质与国标一级苜蓿草粉相当；“二次拌汁料”、“三次拌汁料”之粗蛋白、粗纤维含量符合生长肥育猪饲养标准；加工方式切合稻区紫云英生产实际及产区综合条件，有推广价值，且易推广。     

Physiological and Morphological Characterization of Basalt Milkvetch (Astragalus filipes): Basis for Plant Improvement

Astragalus filipes Torr. ex A. Gray (basalt milkvetch or threadstalk milkvetch) is a legume that is widely distributed in western North America and holds promise for revegetation and restoration programs in the western United States. Seed of 67 accessions was collected in 2003 from Utah, Nevada, Idaho, Oregon, California, and Washington. Field-collected forage samples from these accessions had nondetectable or low levels of selenium, swainsonine, and nitrotoxins. Accessions were evaluated at Providence and Millville in northern Utah in 2005 and 2006. At Providence accessions from north-central Oregon exhibited comparatively high biomass yield in summer and fall during both years. Basalt milkvetch accessions with low biomass generally had high crude protein concentration. Acid-detergent fiber and neutral-detergent fiber were positively correlated with biomass yield (r = 0.42, P < 0.0001; r = 0.57, P < 0.0001, respectively). At Millville accessions from north-central Oregon exhibited comparatively high biomass and seed yield. Seed weight per 100 seeds varied among basalt milkvetch accessions in both years at Millville. Plants at Millville treated with imadicloprid insecticide had greater seed yields than nontreated plants in 2006, but not in 2005. When averaged across sites and years, a high correlation between number of stems and biomass (r = 0.82, P < 0.0001) indicated that number of stems is a reliable predictor of high biomass and seed yield. Principal component analysis of seven consolidated plant traits identified two principal components that accounted for 60% and 15% of the variation among accessions. The first principal component was negatively correlated with elevation (r = -0.71, P < 0.01) and positively correlated with latitude (r = 0.46, P < 0.01). The second principal component was positively correlated with elevation (r = 0.36, P < 0.01) and negatively correlated with latitude (r = -0.47, P < 0.01). These results are beneficial in identifying basalt milkvetch accessions that hold promise for plant improvement efforts.     

黄芪和甘草染色体数目及核型分析

运用植物根尖压片法，对黄芪和甘草两种豆科植物的染色体数目、核型作了研究。结果表明，黄芪的染色体基数X＝8，甘草的染色体基数X＝7。两个种都是二倍体，核型分别为2B和1A，核型公式分别为：2n=2x=16=14m 2sm和2n=2x=14=14m。     

沙打旺黄矮根腐病在我国北方5省区的分布与危害

对5省(区)沙打旺主产区进行了病害调查,除辽宁建平之外,沙打旺黄矮根腐病在甘肃环县、宁夏盐池、陕西横山、内蒙松山和敖汉均有发生,发病率为5.7％～82.6％,病情指数为2.7~53.7。各级严重度的植株在病株中的比例因调查地点而异。与健康植株比较,病株枝条数增加16.7％～63.7％,但单株干重下降8.5％～32.9％。各地的植株密度、牧草产量、平均枝条数和单株干重均存在一定差异,其中在发病率最高的甘肃环县,植株密度、牧草产量分别与发病率和严重度均呈显著负相关(P<0.01)。对影响发病率的因素进行了分析讨论,提出了防治该病的建议。     

Evaluation of clinicopathological parameters in cattle grazing timber milkvetch.

The purpose of this study was to determine whether hematological and serum biochemical parameters could be used to diagnose poisoning in cattle grazing timber milkvetch (Astragalus miser var. serotinus), a nitropropanol-containing legume. Blood samples were obtained from 20 Hereford cattle on timber milkvetch range in southern British Columbia during 1992 and 1993. Relevant changes in blood parameters were not detected and the parameters could not be used to predict nitropropanol ingestion or intoxication. The same parameters were measured in dosing trials with cattle with rumen fistulas, but relevant changes were not detected. Succinate dehydrogenase is the key target in nitropropanol intoxication and an assay for this enzyme may provide a probe for diagnosis.