退耕还草种草养畜大有可为

长江上游坡耕地占总耕地资源的７４％,而四川省２５°以上坡耕地面积便达１１５４万亩,坡耕地严重水土流失已成为长江泥沙的重要来源。为此,四川省政府提出：将坡度在２５°以上的耕地在２００５年前逐步退耕还林、退耕还草,综合治理并改善四川省生态环境。退耕还林以...     

在三峡库区实施种草和生态草地建设的建议

一、生态草地建设是库区退耕坡地利用的重要方式重庆市２５度以上的坡耕地５４３万亩,地势以深丘、山区为主。坡耕地严重水土流失已成为长江泥沙的重要来源。为此,重庆市政府已安排在１０年内首先将坡度在２５度以上的２７５万亩耕地逐步退耕还林还草,加强综合治理、改善库区的生态环境。众所周知,退耕还林或退耕还草都具有防止水土流失,保护生态环境的效果。但是退耕还林和退耕还草又各自具有不同特点。与北方的黄河流域相比,长江流域的三峡库区没有风沙,大风也少,退耕还林的目的并不主要是防止风沙。重庆市库区人口密度大,贫困人…     

浅谈退耕还林还草的意义

<正> 雷波县共有坡耕地面积2.5×104hm2,其中坡度在25°以上的坡耕地有1.37×10hm2,5°～25°的坡耕地有8433 hm2,15°以下的有2820 hm2,全县坡耕地面积在农业用地中所占比重很大,水土流失现象严重,土壤中养分含量低,经济效益低,且生态、社会效益呈负面趋势,有55％的坡耕地应实施退耕还林还草,全县共需要退耕地1.7×104 hm2,涉及人口163629人。雷波县从2000年开始实施退耕还林还草,到2009     

浅谈退耕还林还草的意义

雷波县共有坡耕地面积2.5×104hm2,其中坡度在25°以上的坡耕地有1.37×104hm2,5°～25°的坡耕地有8 433 hm2,15°以下的有2 820 hm2,全县坡耕地面积在农业用地中所占比重很大,水土流失现象严重,土壤中养分含量低,经济效益低,且生态、社会效益呈负面趋势,有55%的坡耕地应实施退耕还林还草,全县共需要退耕地1.7×104m2,涉及人口163 629人.     

退耕还草在改变贵州生态环境中的作用

贵州省土地面积中73%是喀斯特强烈发育的高山区，水土流失极为严重，退耕还草发展畜牧业是解决水土流失的根本措施。     

简析民和县退耕还草之我见

退耕还草、荒山种草是一项集生态、经济、社会效益于一体的综合工程 ,它的实施不但可以防止水土流失 ,改善生态环境 ,而且在增加农民收入 ,调整农业生产结构 ,缓解畜草矛盾方面具有十分重要的意义 ,因而受到广大人民群众的支持。笔者通过退耕还草工作实践 ,就全县退耕还草工作谈谈看法 ,以供探讨。1　任务完成情况 ;2 0 0 0年 ,全县共调拔各类优质牧草种子13 1971万ｋｇ ,完成退耕还草 0 162 9万公顷 ,荒山种草 0 3万公顷 ,林草间作 0 15万公顷。其中紫花苜蓿 0 4 4 95万公顷 ,红豆草 0 0 138万公顷 ,沙打旺 0 1313万公顷 ,老芒麦 0 …     

黄河湟水流域退耕种草技术概述

为了更好的保护我省东部地区的生态环境 ,实施退耕、还林、还草工程是尤为必要的。利用现有资料 ,对我省黄、湟流域坡耕地分布、面积、适种牧草种类以及播期、播量等进行了论述 ;同时还对退耕还草的经济效益作了分析 ,经计算、若退耕种草发展育肥生产 ,每公顷效益是种植粮食的2～ 2 .86倍 ,是种植油菜的 2 .5～ 3 .5倍。     

甘肃省坡耕地利用状况与退耕还林还草技术对策研究

对甘肃省坡耕地的利用状况及其退耕的可行性进行了较为全面的分析,按照因地制宜的原则,将退耕区域划分为陇中黄土丘陵沟壑区、陇东黄土台塬区、山高坡陡的陇南山区与河西防风固沙区四大区,并就各区退耕后的还林还草方式进行了具体的论证,提出了15°～25°和25°以上坡耕地退耕还林还草的具体技术对策。     

“家庭牧场优化模式”在南部县的应用

“家庭牧场优化模式”是由四川省草原研究所研究出的既适合牧区,又适合退耕还草农区的一种新的生产组织形式和可持续发展的综合技术成果。该成果被列为四川省1999年十大农业科技成果之一。南部县自2001年引进该项成果,结合国家退耕还林还草生态项目,实施种草养畜,取得了显著的社会、经济和生态效益。南部县位于四川盆地北部边缘低山深区,嘉陵江中游。全县土地总面积2311.35km2,其中耕地面积6.15万公顷,退耕还林还草面积0.23万公顷,草山草坡8万公顷,桑果园面积2.33万公顷。总人口130万人,其中农业人口113万人。2002年全县出栏生猪116万头,牛1…     

甘孜州天然草地的生态地位与治理对策

四川省甘孜州地处长江源头区，天然草地是全州面积最大的土地类型。但长期以来，天然草地因疏于管理与保护而被不断开垦、掠夺或放牧利用，导致生产力严重下降，生态环境日益恶化并已成为全州乃至整个长江流域经济发展的心腹之患。甘孜州天然草地是长江上游地带性植被，经过长期的演化，适应了当地高寒的严酷生态环境，对于治理长江上游水土流失有着不可替代的作用。草地生态环境的保护、治理与建设已成为综合治理长江流域生态环境、防止水土流失的关键。１甘孜州天然草地的生态地位概括地讲，甘孜州天然草地左右着长江上游流域的生态环境。…     

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。     

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。     

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。     

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。     

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。     

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.