不同浓度的萘乙酸处理对苜蓿无性繁殖影响初探

为提高苜蓿单一性状,加速苜蓿的良种繁殖,针对苜蓿在高寒高海拔地区种植难、返青缓慢的特点, 用不同浓度的萘乙酸处理苜蓿插条,进行了无性繁殖的探索和研究。试验结果表明:萘乙酸处理苜蓿插条的最适浓度是4 g萘乙酸/5kg水,其苜蓿插条成活率达到81．7％,返青率达86．7％。     

苜蓿雄性不育系组织培养技术的研究

以苜蓿雄性不育系Ms-4幼嫩茎段、叶片、叶柄为外植体,诱导苜蓿雄性不育系再生植株.结果表明:叶柄是诱导愈伤组织的良好外植体,体细胞胚诱导率为90%,再生率49%.苜蓿雄性不育系插条生根的最佳处理为接种前用水进行预处理0.5h,外植体为完整插条,培养基为A1、A2,其生根率为97%,生根系数为5.3.     

生根剂对苜蓿扦插的影响初探

选用8920mf多叶苜蓿(Medicago sativa cv.8920mf)作为扦插材料,以常用生根剂吲哚丁酸-萘乙酸(0.2%)对其进行处理,研究自然条件下苜蓿的扦插技术及吲哚丁酸-萘乙酸的施用对扦插材料成活率、发芽天数、生根数、新株高、分枝数的影响,为大田应用扦插技术提供参考.结果表明,自然条件下苜蓿扦插要防止连...     

施氮肥时间对苜蓿结荚率及种子产量的影响

试验以新牧4号紫花苜蓿(Medicago sativa cv.Xinmu No.4)为材料,研究在苜蓿不同生育期施氮肥对苜蓿结荚率、千粒重、种子产量等的影响,为提高苜蓿结荚率、增加种子产量提供依据。结果表明,返青期施氮肥处理的苜蓿荚果结荚率、种子千粒重以及种子发芽率均高于其他处理,依次为63.87%、2.01g和85.33%;但其单序荚果数和结荚率均低于其他处理;在各个处理中,现蕾期施氮肥处理苜蓿种子产量最高(802.16 kg·hm-2),分枝期次之(641.29kg·hm-2),分别是对照(390.34kg·hm-2)的2.05倍和1.64倍。本研究结果能够为苜蓿种子田的合理施肥提供理论依据。     

留茬高度对苜蓿再生干草质量及返青率的影响

为了解决生产中由于留茬高度不当造成苜蓿再生干草产量、品质及翌年返青率较低的问题,试验选择"金皇后"紫花苜蓿,测定分析不同留茬高度处理对苜蓿再生干草产量、品质及翌年返青率的影响,以确定最适留茬高度。结果表明:随着留茬高度的增加,苜蓿干草产量呈降低趋势;留茬≥8~11 cm时,苜蓿再生干草粗蛋白含量、相对饲用价值较高,分别为20.79%、147.24%,其次为留茬≥5~8 cm,两者间粗蛋白含量、相对饲用价值差异不显著(P0.05);留茬≥8~11 cm时,苜蓿根内可溶性糖含量为89.41 mg/g,翌年返青率为79.89%,显著高于其他处理(P0.05)。说明凌海地区第一、二、三茬苜蓿以留茬高度≥5~8 cm为宜,但第四茬苜蓿应留茬≥8~11 cm。     

不同处理方式对10个苜蓿品种扦插成活率的影响分析

通过研究不同处理方式对苜蓿扦插效果的影响,发现中苜1号、中苜3号、阿迪娜、阿尔岗金4个苜蓿品种和现蕾期苜蓿枝条扦插成活率均超过90%;苜蓿中部和基部枝条扦插成活率显著高于顶部枝条扦插;第一茬次苜蓿现蕾期扦插成活率高于第二、三、四茬;使用生根剂(吲哚丁酸-萘乙酸)处理苜蓿扦插枝条、苜蓿扦插枝条下切口斜切以及扦插土壤为基质+细沙处理均能够显著提高苜蓿枝条扦插成活率。     

春苜蓿的管理要点

春季气温逐渐回升,昼夜温差逐渐缩小,越冬苜蓿开始返青复生.此期要及早进行管理,让苜蓿早返青,出好苗,提高全年的产草量和经济效益.     

覆盖、灌水对准格尔苜蓿越冬率及田间土壤温湿度的影响

在鄂尔多斯地区,通过不同时间的覆盖和灌溉处理,比较准格尔苜蓿两年间越冬率、田间土壤温度、土壤容积含水量的差异,对准格尔苜蓿越冬性进行了回归分析。结果表明,两年间,封冻前灌水的准格尔苜蓿越冬率最高。封冻期,封冻前至解冻前覆盖的苜蓿田土壤温度极显著高于其他处理;返青期,解冻前至返青覆盖的苜蓿田土壤温度最高。封冻前,封冻前灌水的苜蓿田土壤容积含水量极显著高于其他各处理;解冻后,解冻后灌水的苜蓿田土壤容积含水量最高。解冻后苜蓿田土壤容积含水量与准格尔苜蓿越冬率呈极显著正相关,并且对苜蓿越冬能力起了最主要和最直接的作用。     

紫花苜蓿越冬性研究概述

通过典型案例的调查分析,阐述了与苜蓿Medicago sativa越冬性有关,但又不太被人重视的5个问题:苜蓿品种、播种期、生境、田间冬春季管理、刈割制度.同时也讨论了苜蓿根茎受冻后的4种表现:根茎未受冻,能正常返青、根茎上端受冻,推迟返青、根茎全部受冻,不能返青、根茎和根受冻,不能返青.     

应用高分卫星遥感数据评价紫花苜蓿人工草地返青状况

利用国产GF-2和GF-6高空间分辨率卫星遥感图像,以内蒙古阿鲁科尔沁旗为研究区,结合实地调查,评价苜蓿人工草地返青状况.结果表明:(1)依据样地观测数据,发现植被覆盖度与苜蓿植株高度、株数均呈现出极显著的正相关关系,为此提出了基于植被覆盖度的苜蓿人工草地返青状况评价指标;(2)建立了苜蓿人工草地返青期垂直植被指数(P...     

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.