广东家蚕微粒子病流行状况及原因分析

调查与分析了1990年以来广东家蚕微粒子病的流行状况及原因。广东蚕种生产比较稳定,原种微粒子病蚕种淘汰率低,普通种微粒子病蚕种淘汰率7年平均为2.8％。在实施蚕种集团磨蛾集中检疫条件下,胚种传染不是广东微粒子病流行的原因。原种发生微粒子病的传染源主要来自野外昆虫;普通种生产微粒子病流行的原因是丝茧育蚕区广泛污染,病原多渠道传入原蚕区及原蚕区净化不彻底,原蚕期食下感染病原所致。丝茧育蚕区病原随洪水扩散至原蚕桑园和养蚕环境是近年几个重疫场微粒子病严重流行的主要原因。外地不良蚕种流入是导致蚕区病原污染的一个重要因素并两次使数县丝茧育遭受严重损失。发现广东蚕区桑园及野外昆虫患微孢子虫病比较普遍,对蚕种生产存在交叉感染的危险。提出了宏观防治对策及开展几项关键性防治技术的建议。     

农村原蚕分户制种微粒子病检疫抽样方案

农村原蚕分户制种微粒子病抽样检查方法是近年来家蚕微粒子病检疫急需解决的新课题。在全面分析农村原蚕微粒子病批内分布状况的基础上 ,提出了农村原蚕分户制种微粒子病抽样检查方案 ,包括并户检查和分户检查两个步骤。通过对实际调查数据进行计算机模拟抽样检查证明 ,该方案在保证检验批质量符合部颁标准的前提下 ,既兼顾了丝茧育农户的利益 ,又兼顾了蚕种场和种茧育农户的利益 ,同时显著减少了集团镜检次数 ,兼顾了蚕种检验部门的利益。     

微粒子病流行的病源分析和防治措施

<正>微粒子病的流行,是通过胚种传染和食下传染两条途径,使蚕儿感染发病。因此它的病源是带毒蚕种和带毒的养蚕环境、桑叶以及带毒的野外昆虫。我省对三级原种繁育,实行全部对号袋母蛾,全部显微镜检验,发现有毒蛾张,则整张蚕种淘汰。所以种茧育用种,带毒的可能性极小,原蚕区饲养原蚕,在蚕期中大都发育正常,防病预知检查亦未发现有微粒子孢子,直到母蛾镜检时才发现“微毒”,这充分证明原蚕种无毒,主要是在壮蚕期,特别到5龄期防病消毒工作不彻底,受食下微粒子孢子感染的,蚕期没有症状表现,种茧调查成绩和制种量亦影响不大。 80年代以来,我省蚕桑生产发展很快,蚕种供不应求,促使大规模发展原蚕区生产蚕种,现在已有80%左右的普通种是农村原蚕区种茧生产的。由于蚕种场技术力量和管理水平跟不上原蚕区发展的要求,对微粒子病的危害放松警惕,使已被控制的微粒子病又死灰复燃。一般原蚕区春季饲养原蚕,夏秋期饲养丝茧蚕,丝茧蚕用的普通种都是抽样检验母蛾,虽然用的都是合格普通种,但在合     

家蚕微粒子病的综合防治

家蚕微粒子病是经蚕食下传染和胚种传染的一种毁灭性蚕病,严重威胁着蚕种场的生存和蚕桑事业的发展.目前,对家蚕微粒子病的防治可以从三个方向努力.首先是预防.主要是防止微粒子病对家蚕的感染.常以补正检查、预知检查、母蛾检查、环境及桑叶消毒等技术措施为有效手段,并已取得了系统有用的研究成果,广泛运用于家蚕繁育的全过程.第二为治疗.即主要是对家蚕添食抗微药品,如防微灵、克微宝等,以此来控制家蚕微粒子在蚕体的增殖.第三为育种防治.即用生物工程技术将抗微粒子病基因导入经济性状好的蚕品种内,培养出在感染微粒子病毒的任何浓度下绝对不会发生家蚕微粒子病的蚕种,不过该研究还只是一种设想.     

规范蚕种质量检验 维护蚕业生产安全

家蚕微粒子病是危害蚕种生产的主要传染性蚕病。为综合防控家蚕微粒子病危害,江苏蚕种行业多措并举加强蚕种生产过程控制和蚕种产品质量检疫,较好地维护了丝茧生产安全。但近年来由于蚕种生产方式、生产人员、生产环境、生产条件变化及野外昆虫消长等因素,家蚕微粒子病对江苏蚕种生产的危害依然严重。本文就规范蚕种质量检疫,有效控制家蚕微粒子病胚种传染谈点粗浅认识。     

增加检验项目 提高防微效果

家蚕微粒子病是经蚕食下传染和胚种传染的一种毁灭性蚕病,严重威协着蚕种场的生存和蚕业生产的发展.为此,蚕业工作者采取了多种防微措施,以求减少家蚕微粒子病对蚕业生产的危害.     

环境中微粒子病原的调查及其防止

家蚕微粒子病是一种危害极大的传染性蚕病。近年来,该蚕病蔓延扩散,严重影响我省蚕业生产。已知家蚕微粒子病的传染途径有二:一为胚种传染,二为食下传染。对胚种传染,蚕业界早已广泛重视,形成了一套严格的检验制度。对食下传染罕见报道,以致形成季季都检种、烧种,然而仍然控制不了此病,甚至引起此病暴发。因此,对食     

广西家蚕微粒子病流行规律分析

家蚕微粒子病是一种危害性很强的蚕病。根据家蚕微粒子病具有胚种传染和食下传染两种传染方式特点,采用数理统计方法对检验数据进行详细分析研究,探索广西家蚕微粒子病发生原因和流行规律。结果显示,通过严格执行现行检疫技术标准,在蚕种生产中基本能控制家蚕微粒子病胚种传染危害。调查发现养蚕环境中微孢子虫污染严重,对应蚕生产蚕种的母蛾微粒子病发生率高,两者存在显著相关性,由此证明养蚕环境中微孢子虫污染严重造成的家蚕食下传染是家蚕微粒子病发生的重要原因;在蚕种生产中,气象因素对家蚕微粒子病发生也有影响。气温影响最为重要,降雨、日照起到辅助效果;建立两种基于蚕种微粒子病发生与环境微孢子虫分布关系以及与气象因子关系的数学模型,对家蚕微粒子病发生进行预测预报,为蚕种生产防控家蚕微粒子病提供依据。     

家蚕细菌性肠道病、中肠型脓病、浓核病和微粒子病的初步比较

通过同时分别添食家蚕细菌性肠道病、中肠型脓病、浓核病和微粒子病病原给家蚕,比较四种蚕病的发病过程、病蚕中肠病变、病原胚种传染情况和药物治疗效果。发现四种蚕病都有蚕体群体发育不齐的现象,细菌性肠道病发病时间最早,但发病较轻的蚕体有病情自愈的现象;浓核病发病过程最长,与对照差异也最大;中肠型脓病中肠后端呈乳白色;只有微粒子病对家蚕有胚种传染：只有细菌性肠道病对抗生素治疗有效果。     

对家蚕微粒子病感染规律的研究

本文研究了家蚕微粒子病的食下传染、胚种传染、蚕座传染的规律性。指出对丝茧育来说感染越早危害越大,对种茧育来说感染越晚危害越大;食下感染的次数具有累积效应,但以起蚕期和将眠期（5龄为将熟前）影响最大;在蚁蚕就有感染蚕存在的情况下,丝茧育有二个蚕座传染周期,种茧育有三个蚕座传染周期;淘汰措施无论对丝茧育还是种茧育均是有效的,但其有效性随着基数毒率的增大而降低,只有当丝茧育的基数毒率在3％以下,种茧育的基数毒率在1％以下时淘汰措施才能取得95％以上的有效性,而且淘汰得越早越彻底效果越好;微粒子病对次代蚕的遗传毒率是一个变量,母蛾的带毒程度是影响其变化的主要因素;有毒母蛾产下卵通过催青后,遗传毒率在蚁蚕期已基本达到最大值,蚁蚕经高温高湿处理后遗传毒率的增幅不大而主要是孢子密度的增加;同一有毒母蛾产下卵用不同方式保护后,越年种蚁蚕毒率显著大于即时浸酸种蚁蚕毒率,说明微孢子在蚕卵的休眠期仍在增殖中;胚种传染带毒蚕的死亡时期大部分在3龄以前,影响发病死亡早晚的主要因素是母蛾的带毒程度。     

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。     

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.     

Mechanism of Action of Probiotic Function of Lactobacilli

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。 …