不同温度处理对臂形草种子发芽速率的影响

通过不同温度处理5个不同品种的臂形草种子,初步得知,采用80℃水浸种4min,刚果臂形草种子的发芽速率最快,7d发芽势达39.25%,发芽率达57.25%,发芽指数达7.48;采用60℃水浸泡种子14h后,珊状臂形草种子的发芽速率最快,发芽势为13.25%、发芽率为23.25%,发芽指数为2.60。其他3个品种效果不明显,三项指标均较低,有待采用其他方法处理种子。     

俯仰臂形草种子休眠原因的研究

通过测定不同储存时间和浓硫酸处理的臂形草种子的发芽指标及电导率,结果表明,储存2年的俯仰臂形草种子可作为播种材料;浓硫酸处理15min能显著(P0.01)提高贝斯莉斯克俯仰臂形草种子的发芽势和发芽率;破除休眠的3号和深度休眠的4号种子不同部位的甲醇提取液对油菜籽的发芽试验表明,30%,50%和80%原提取液处理发芽势为0,当把提取液中甲醇蒸发提取后,4号胚和胚乳提取液处理油菜籽发芽势与CK无显著性差异(P0.01),说明甲醇会影响植物的发芽,休眠的俯仰臂形草种子存在发芽抑制物质,抑制物主要存在于种子的稃内。     

PEG模拟干旱胁迫下3种臂形草属植物种子萌发期抗旱性评价

干旱在我国广泛分布,筛选抗旱型牧草对充分利用干旱土地具有重要意义。本研究以3种臂形草属植物四生臂形草[Brachiariasubquadripara(Trin.)Hitchc.]、臂形草[Brachiariaeruciformis(J.E.Smith)Griseb.]和多枝臂形草[Brachiariaramosa(Linn.)Stapf]为材料,用不同浓度PEG-6000溶液(0%,5%,10%,15%,20%)模拟干旱胁迫处理,对种子的发芽率、发芽势、发芽指数、活力指数、相对含水量、鲜重、胚轴长和根长进行了比较研究,试验结果表明,随着PEG-6000溶液浓度的增加,3种臂形草种子的发芽率、发芽势、发芽指数、活力指数、相对含水量、鲜重、胚轴长整体呈递减趋势。多枝臂形草的抗旱性最好,其发芽率、发芽势、发芽指数、活力指数、相对含水量、鲜重、胚轴长在低PEG-6000浓度处理下维持较高的水平,并且根长在10%、15%及20%的PEG-6000处理下显著高于对照(P0.05)。四生臂形草抗旱性较好,臂形草抗旱性较差。     

赖草种子发芽特性研究

通过采用聚乙二醇、吲哚乙酸两种化学试剂处理,提高赖草种子的发芽率和发芽势。研究结果表明:收获三年的赖草种子采用不同种类的化学溶液处理,不但发芽率理想,而且发芽势较高。其中,在14℃避光条件下,用不同浓度的聚乙二醇溶液处理赖草种子10h,在15℃~25℃的温度中进行变温发芽,随着其浓度的升高,发芽势升高,在浓度为35%时,其发芽势高于对照50%,达到极显著水平;而吲哚乙酸处理对赖草种子发芽势没有影响,但能提高赖草种子发芽率,在浓度为20ppm时,达到显著水平。因此,温度在15℃~25℃条件下,收获三年的赖草种子采用35%聚乙二醇或20ppm吲哚乙酸处理赖草种子后发芽较为理想。     

少花蒺藜草种子水浸提液对3种禾本科牧草种子萌发的化感效应

为了解少花蒺藜草（Cenchrus pauciflorus）的化感潜力,试验采用生物测定法研究了不同浓度（0、25%、50%、75%、100%）的少花蒺藜草种子水浸提液对无芒雀麦（Bromus inermis）、梯牧草（Phleum pratense）及冰草（Agropyron cristatum）种子的化感作用。结果表明,少花蒺藜草种子水浸提液对3种受体植物种子萌发和幼苗生长均有不同影响。少花蒺藜草种子水浸提液对无芒雀麦种子的发芽势、发芽指数无显著影响,但对其根芽比有显著影响;少花蒺藜草种子水浸提液对梯牧草种子的发芽率、发芽指数、发芽势影响不大,但对根芽比影响显著（P〈0.05）;少花蒺藜草种子水浸提液对冰草种子的发芽率、发芽指数、发芽势及根芽比均有显著影响（P〈0.05）,在100%水浸提液浓度下发芽率仅为18.6%,比对照组低56.8%,发芽势和发芽指数分别为6.7%、3.24,比对照组分别低39.3%、8.94。     

羊草种子发芽试验方法的研究

为了探究羊草种子快速萌发的方法,从而为羊草人工草地的建植提供科学依据,试验以吉农一号、吉农二号、吉生一号、白城野生4份羊草种子为研究对象,观察其在不同预处理方式(浓硫酸浸种、不同温度、预冷处理)下的萌发特性。结果表明:不同品种羊草种子的萌发对不同预处理方式的响应是不同的,浓硫酸浸种能不同程度地提高羊草种子的发芽率、发芽指数和发芽势,且处理15 min的发芽率最高;4个羊草品种在15～35℃的温度范围内均能发芽,最适宜的温度为25℃;4℃预冷处理7,14,21 d羊草种子的发芽率、发芽指数和发芽势均显著高于对照组,其中预冷处理7 d最高。说明羊草种子在经过4℃预冷处理7 d后再用浓硫酸处理15 min,在25℃条件下种子发芽效果最佳;4个羊草品种中,吉农一号各处理的发芽指标均显著高于其他品种。     

不同处理方法对地锦草发芽率的影响

通过发芽试验探讨不同温度、pH值和湿度处理对地锦草(Euphorbiae humifusa)种子萌发的影响。结果表明:不同温度、pH值和湿度对地锦草种子的萌发均有显著影响。地锦草种子在30℃左右时发芽率和发芽指数最高,分别为52%和22.6。不同pH值处理时,pH值为7时其发芽率和发芽指数最高,分别为48%和23.79。不同湿度处理时,当湿度为90%时,地锦草种子的发芽率和发芽指数最高,分别为55%和23.02。     

盐分与温度对高丹草种子萌发的影响

为明确高丹草在种子发芽阶段对盐分、温度的响应,采用4个NaCl浓度(0、50、150、250mmol/L)和3个温度(15℃、25℃、35℃)处理高丹草种子。结果表明:25℃时,NaCl溶液处理均使高丹草种子的萌发延迟,而发芽温度为35℃时NaCl处理并不影响种子的正常发芽时间。15℃时,150mmol/L和250mmol/L NaCl处理种子均未萌发。25℃时,在0~250mmol/L范围内随NaCl浓度的提高高丹草种子发芽率、发芽势、胚根长、胚芽长以及幼苗干鲜重均呈下降趋势,其中250mmol/L NaCl处理组发芽率和发芽势分别较对照降低了85.9%和93.9%。在高NaCl浓度(150mmol/L和250mmol/L)时,与25℃相比,35℃可显著提高高丹草种子的发芽率、胚根长以及幼苗干鲜重。NaCl浓度为250mmol/L时,35℃处理组的种子发芽率为66.7%,比25℃处理组提高了50%。总体来说,在0~250mmol/L范围内随NaCl浓度的提高,高丹草种子萌发和幼苗生长受到的抑制作用增强,35℃的发芽温度可在一定程度上缓解NaCl溶液的抑制作用。     

几种处理对银合欢种子活力的影响研究

用热水、酸蚀以及磨破种皮处理银合欢(Leucaena glauca)种子,打破其休眠。结果表明,不同浓度的硫酸处理对银合欢种子的发芽率、发芽指数、发芽势影响差异显著(P<0.05),25%硫酸处理对银合欢种子发芽率、发芽指数、发芽势无显著影响(P>0.05),而98%的硫酸处理对银合欢种子发芽率、发芽指数、发芽势有极显著影响(P<0.01)。75℃的热水以及磨破种皮处理对银合欢种子的发芽率、发芽势均有提高。不同处理对银合欢种子发芽率影响由大到小的排序为:98%硫酸>75℃水>75%硫酸>研磨种子>50%硫酸>25%硫酸>无处理种子。98%硫酸处理银合欢种子20 min是最佳处理方式。     

不同浸种方法对马棘种子萌发的影响

马棘种子以播种繁殖为主,其种子硬实率高,生活力和发芽率低。本试验通过将马棘种子浸泡在初始温度为70℃、80℃、90℃、100℃的蒸馏水中,自然冷却后继续浸泡的总时间分别为4h、8h、16h、24h;98%H₂SO₄溶液对马棘种子浸泡不同时间(1min、3min、5min、7min);20%、25%、30%、35%、40%的NaOH溶液分别浸泡马棘种子1h,对以上3组试验处理后的种子测定其发芽势、发芽率、发芽指数、发霉率以及腐烂率,确定不同处理对马棘种子萌发的影响。结果表明:80℃浸泡16h,马棘种子的发芽势(26.67%)、发芽率(54.00%)、发芽指数(23.31)高于其他处理;H₂SO₄浸泡马棘种子3min时发芽势(54.00%)、发芽率(62.67%)、发芽指数(32.09)高于其他处理;35%NaOH处理马棘种子,发芽势(22.00%)、发芽率(48.00%)、发芽指数(20.28)高于其他处理。综合比较马棘种子发芽效果最佳的3种处理,H₂SO₄...     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.