河南柞蚕全龄老梢育技术探讨

河南省是一化性柞蚕主产区,放养方法与其它地区不尽相同.在春柞蚕放养过程中,除稚蚕期利用很少老梢柞叶外,四、五龄壮蚕期历来采用火芽饲养.而蚕坡的轮伐直接影响柞树的生长,且存在着柞树有效产叶量低,养蚕劳动强度大,生态效益差等缺点,是柞蚕生产急待解决的问题之一.为此,我们依照柞树、柞蚕的生长发育协调一致满足蚕儿生理需要的原则,就河南柞蚕全龄老梢育技术,在此与同行进行探讨.     

河南柞蚕放养区全龄老梢育生产技术

分析了河南省柞蚕区放养人员的结构和现行放养技术,论述了在一化性柞蚕区推广全龄老梢育的现实意义,总结提出了柞树修剪和柞蚕放养的关键技术。     

柞树生长冗余和补偿作用的利用

发展柞蚕生产是否会对柞树的生长以及山区的生态环境产生不良影响,一直是一个存在争议的问题。根据植物的生长冗余理论与补偿机制并结合已有的柞树去叶试验和柞蚕放养试验结果分析表明:柞树部分去叶后有利于光合同化产物向枝条和剩余叶片中的分配,补偿因去叶带来的地上与地下部分的生长不平衡,直到二者恢复正常比例;柞树的生长冗余现象和补偿作用主要体现在茎、叶等主要部位与器官,以及柞树夏梢的二次生长方面。据此认为,采用科学方法放养柞蚕和管理柞树能够使柞树的生长特性与放养柞蚕有机结合,使柞树生长保持一种相对平衡的状态,实现柞林资源的可持续利用。     

柞树主要害虫与防治(二)——芽叶害虫

柞树芽叶害虫依据危害时期可分为春季害虫和秋季害虫二大类,春期害虫主要集中在早春危害冬芽芽苞、嫩芽、嫩叶以及嫩梢生长点,秋期害虫的发生与秋蚕放养时期基本一致,与秋柞蚕争食或污染柞树叶片。柞树芽叶害虫的危害,不仅降低了柞树叶片的质量和产量,影响柞蚕生产;同时还影响柞树的长势,不利于柞树的绿化和水土保持效果。     

两人两月挣四万 柞蚕养殖效益好

正今年春季,巴州区梓橦庙镇谢家湾村梓睿柞蚕养殖专业合作社理事长喻志国,在谢家湾村通过租赁流转了100hm~2(1500亩)柞林,建成生态柞园53hm~2(800亩),并专程从辽宁省西丰县聘请2名具有近20年柞蚕养殖经验、技术娴熟的养蚕能手,放养柞蚕种3斤,收获柞蚕茧650kg,蚕茧销售产值达4万元。摸清实情,是放养柞蚕权宜之计。"首先是不清楚这边的柞树与辽宁那边柞树品种的差异,也     

柞树夏季剪梢增产试验

<正>辽宁省秋柞蚕开始放养的时间,是在7月下旬至8月上旬.此时天气炎热,而柞树发育又处于夏芽老化、秋芽未发的时期.利用这种老叶放养秋蚁蚕,会造成秋蚕生产的减产.为使柞树发育与蚕儿生理要求相适应,对(?)年生柞树采取夏季剪梢,使其在预则内萌发嫩叶进行养蚁保苗.试验方法一、不同剪梢方法试验 将供试的二年生辽东栎采取三种剪梢方法,将柞树的夏芽全部从基部1cm处剪去(简称全剪法);将树墩中几个主干上发的夏芽剪去(简称轻剪法);从柞树春条中部剪去(简称重剪法).     

柞蚕场地腐熟物质层与柞树生长发育的关系

柞树叶是放养柞蚕的重要饲料,柞树生长地理条件对柞树叶的质量起着至关重要的作用。场地内腐熟物质多,不但土质肥沃,而且保持土壤水分,增加场地湿度,柞树生长旺盛,叶质也优良,放养柞蚕产茧量也高,茧质也好。因此,保留柞蚕场地树下杂草、枯枝、落叶,增加场地腐热物质层,提高场地肥力是养树养蚕的重要手段,也是养蚕获得丰收的先决条件。为使柞树永续利用,充分利用好这一经济林,特对克山县养蚕场地进行了粗浅的调查。从调查结果分析看:场地不但存在着严重的沙化现象,还因超负荷的放养柞蚕,加剧了树质下降而影响整个树体的生长发育。现将调查结…     

我国柞蚕业起源问题的探讨

<正> 我国古代人民对柞蚕的放养和利用,是继发明桑蚕技术之后,对世界人民的又一贡献。古代柞蚕业的历史,大致可分为发现、提倡和发展三个时期。 柞树,《诗经》中已有记述。柞蚕究竟什么年代被发现,尚缺乏史料考证。柞蚕原是生活在柞树上的野生昆虫,由于柞树大都散生在山野,加以柞蚕的敌害很多,生存不易,可以推想,人类对柞蚕的发现以至引起重视,比起桑蚕要晚着一段相当长的时间。目前所发现最     

高产稳产柞坡修剪技术初探

对不同树龄的柞树分别采用轻剪、重剪,轻捎、根刈等不同型式的整伐处理,调查柞叶的适熟期变化,蚕儿的适宜放养龄期,以及单位面积产叶量的增幅,由此提出蚕坡轮伐制度的变革意见。     

五龄柞蚕绢丝腺增重规律及其与叶质的关系

<正>五龄柞蚕绢丝腺增长规律,苏联学者T.C.已有研究.而壮蚕期饲料对五龄柞蚕绢丝腺的增长也有一定关系.摸清柞树叶质对柞蚕绢丝腺增长的影响,以便改善饲养管理方法,这对一化性柞蚕生产具有重要意义.现将部分调查结果报道如下.材料和方法一、供试柞蚕品种地方品种“方12号”.二、材料蚕放养方法(一)大眠场二年生老柞育:一至三龄蚕按河南普通方法放养,饲料为二年生老柞(河南俗称老梢),四龄蚕继续使用二年生老柞饲料喂养.当大眠蚕(四龄眠蚕)起身时,挑选同时期眠起的五龄蚕为材料.于五龄第2天8时.再将柞蚕移人当年生芽柞(河南俗称火芽)上放养.     

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.