柞蚕茧微生物发酵脱胶工艺优化

利用从环境中分离筛选出的产高活性胞外蛋白酶的枯草芽孢杆菌(Bacillus subtilis) 10C菌株,通过微生物发酵法实现对柞蚕茧壳的脱胶。采用单一变量法和正交试验优化发酵脱胶工艺,试验结果表明,应用芽孢杆菌10C菌株对柞蚕茧壳进行发酵脱胶,在初始p H值为7、料液质量浓度为22 g/L、以玉米粉作为发酵液的碳源且质量浓度为15 g/L的条件下,35℃、150 r/min发酵18 h,柞蚕茧壳用微生物发酵脱胶后的脱胶率达到了13. 38%。柞蚕茧壳用微生物发酵法脱胶的效果与传统的碱法脱胶和酶法脱胶相当,且对环境无污染。     

添食枯草芽孢杆菌对家蚕生长与生产性能的影响

探讨采用喷雾法将枯草芽孢杆菌活性溶液喷洒于桑叶表面，从3龄家蚕幼虫开始饲喂，并以空白组为对照，研究枯草芽孢杆菌活性溶液对家蚕各龄期体重、生产性能等各项指标的影响。结果表明：从3龄初到4龄初，试验组增重70．49g，比对照增加10％；从4龄初到5龄初，试验组增重333．05g，比对照增加13％；5龄末，试验组增重1301．58g，比对照增加15％。试验组平均蛹体1．3704g，比对照增加10％。试验组平均茧壳量O．433g，比对照增加7％。试验组茧层率24．01％，比对照降低1．8％。采用相关统计学检验方法，测得各指标间差异明显。由此可见，枯草芽孢杆菌对家蚕生长有一定的促进作用，但在茧层率方面有一定的负面影响。     

(一)微量元素和其他物质对柞蚕发育和产量的作用

在隔离了的柞栎树上放养柞蚕(品种为“依常”)在每龄蚕眠后和未熟蚕之前用铁、铜、锌等盐类及抗生素溶液喷射。短杆菌肽添食区的五龄蚕体重显著较对照区重(6.61～7.17克,对照区为4.09—5.34克)。短杆菌肽添区(0.002％),青霉素添食区(1立方公分100单位)和链霉素添食区(1立方公分100单位)的大全部蚕儿提早1～2天热蚕,而0.01％硫酸鉄、硫酸锰和异茁长素溶液以及0.5％米克罗席(抗生物质之一)溶液等添食区则提早4～6天熟蚕。链霉素区的健蛹率为100％,青霉素区94％,异茁长素90—92;硫酸铁与硫酸锌区89％,对照区为78—80％。短杆菌肽区的最大全茧量为12克     

响应面法优化柞蚕蛹多糖的提取工艺及其抑菌活性研究

为确定柞蚕蛹多糖的最佳工艺条件及其抑菌活性,试验将柞蚕蛹作为材料,利用水提取法提取柞蚕蛹多糖,并用滤纸片法检测柞蚕蛹多糖的抑菌活性。结果表明,柞蚕蛹多糖最适宜的提取条件为料液比1∶45 g/mL,时间3.16 h,温度75℃,进行3次重复试验,所得柞蚕蛹多糖平均提取率为1.38%。柞蚕蛹多糖对金黄色葡萄球菌、枯草芽孢杆菌和大肠杆菌均有抑制作用,对金黄色葡萄球菌抑制效果最好。 [关键词]柞蚕蛹|多糖|提取|响应面|抑菌     

枯草芽孢杆菌单菌及其与甘露寡糖联用对雪山草鸡生长性能和肠道pH值的影响

本试验旨在研究枯草芽孢杆菌单菌及其与甘露寡糖联用对雪山草鸡生长性能和肠道p H值的影响。试验选用1日龄雪山草鸡公雏鸡1 800只,随机分为5组,每组6个重复,每个重复60只。对照组饲喂基础日粮,试验组(Ⅰ、Ⅱ、Ⅲ、Ⅳ)分别饲喂基础日粮+1 g/kg枯草芽孢杆菌BLCC1-0155,基础日粮+1 g/kg枯草芽孢杆菌BLCC1-0155+0.8 g/kg甘露寡糖,基础日粮+1 g/kg枯草芽孢杆菌BLCC1-0048,基础日粮+1 g/kg枯草芽孢杆菌BLCC1-0048+0.8 g/kg甘露寡糖,试验期为80 d。结果显示:Ⅰ、Ⅱ、Ⅲ、Ⅳ组雪山草鸡较对照组在1~40日龄和41~80日龄的日采食量、平均日增重和料重比等生长性能指标上以及在第40、80天的十二指肠、空肠和回肠p H上均无显著差异(P0.05)。结果表明,枯草芽孢杆菌BLCC1-0155和BLCC1-0048单菌及其与甘露寡糖联用均对雪山草鸡生长性能和小肠p H值无显著影响。     

草甘膦和草铵膦2种桑园常用除草剂对家蚕原种生长发育的影响

采用食下毒叶法,测定了2种桑园常用除草剂草甘膦钾盐水剂和草铵膦水剂对云7A等8个家蚕品种的急性毒性和对云7A等3个家蚕品种的慢性毒性,以清水处理的桑叶为对照。急性毒性测定结果表明:在添食2种除草剂的毒叶后48 h内未造成家蚕直接中毒死亡,在相同的药剂和浓度下不同品种家蚕的中毒程度不同,但中毒症状相似。慢性毒性测定结果显示:草甘膦钾盐水剂处理除了添食148.00 mg/L毒叶的菁松A比对照延迟6 h外,其他处理浓度及品种的龄期经过与对照一样;添食148.00 mg/L毒叶的云7A的全茧量和蛹体质量与对照间差异显著,添食37.00～148.00 mg/L毒叶对菁松A主要产茧性状无显著不良影响,添食148.00 mg/L毒叶的皓月A的全茧量、茧层量和蛹体质量与对照间差异显著。草铵膦水剂3种浓度对3龄家蚕的龄期经过无显著不良影响,但会造成4龄、5龄经过延迟,其中云7A添食22.73～90.91 mg/L毒叶的家蚕4龄经过比对照延迟9 h～3 d 23 h,添食22.73～45.46 mg/L毒叶的家蚕5龄经过比对照延迟1 h～2 d;添食90.91 mg/L毒叶的除了菁松A的家蚕能上蔟结茧外,其他2个品种的家蚕均在5龄饷食后逐渐体缩失水而死或发育不良,添食22.73～45.46 mg/L毒叶的3个品种家蚕全茧量、茧层量与对照间差异显著,添食22.73～90.91 mg/L毒叶的菁松A的家蚕茧层率和蛹体质量与对照间差异显著,添食22.73～45.46 mg/L毒叶的皓月A的家蚕蛹体质量与对照间差异显著。2种除草剂对3个家蚕品种的生长发育及经济性状均存在不良影响,建议桑园使用此类除草剂除草时应选在非蚕期进行。     

耐碱性短小芽孢杆菌木聚糖酶在枯草杆菌中的表达及发酵条件优化

研究耐碱性短小芽孢杆菌木聚糖酶在枯草芽孢杆菌中异源表达。从耐碱性木聚糖酶高产短小芽孢杆菌BYG5-20中克隆得到带有自身启动子的木聚糖酶基因xynA,将其构建在大肠杆菌-枯草芽孢杆菌穿梭载体pGJ148中得到重组质粒pGJ148-xynA。采用电转化法将重组质粒pGJ148-xynA转入枯草芽孢杆菌1A747中,得到重组菌B.GJ148-xynA,然后进行诱导表达以及培养基的优化。重组菌GJ148-xynA发酵上清液中木聚糖酶酶活可达93.32IU/ml。耐碱性短小芽孢杆菌木聚糖酶基因xynA可以在枯草芽孢杆菌中实现异源表达,为枯草芽孢杆菌木聚糖酶分泌表达系统的进一步优化奠定了基础。     

关于柞蚕内印茧与子代软化病发生几率的相关性探析

通过对柞蚕茧壳内污染蛹的子代软化病发生情况试验调查,并以洁净茧壳内蛹的子代软化病发生情况作对照,得出了茧壳内污染状况与蛹的子代软化病发生量呈正相关性的结论,并提出了在种茧期有效减轻子代软化病发生的具体措施。     

饲用枯草芽孢杆菌SR096产孢培养基及培养条件的优化

试验旨在为了降低枯草芽孢杆菌SR096的工业生产成本和提高发酵液的芽孢含量,采用单因素试验和响应面法试验设计对菌株SR096的培养条件和发酵培养基组分优化,优化后的培养基组分为:葡萄糖7.5 g/L、玉米粉15.7 g/L、黄豆粉45.0 g/L、柠檬酸钠4.5 g/L、碳酸钙2.0 g/L、硫酸镁1.0 g/L,经验证在5 L发酵罐中以接种量3%、37℃、250 r/min条件下培养30 h,枯草芽孢杆菌SR096发酵液的活菌含量为1.67×10^10 CFU/mL,芽孢含量为1.56×10^10 CFU/mL,芽孢率为93.3%,为枯草芽孢杆菌SR096后期的产业化放大和推广应用奠定基础。     

枯草芽孢杆菌发酵黄芪提取液培养基优化研究

为了研究枯草芽孢杆菌发酵黄芪提取物的最佳培养基以及防腐剂对枯草芽孢杆菌存活率的影响,试验采用正交设计对培养基配方进行优化,并进行了扩大培养试验;用单因子试验法测定了枯草芽孢杆菌存活率。结果表明:培养基黄芪生药含量为0.5 g/mL,每100 mL培养基中含豆粕2.0 g、玉米2.0 g、麸皮2.5 g时枯草芽孢杆菌活菌数最多,可达到8.34×10~8cfu/mL,芽孢率大于90%。与摇瓶培养相比,发酵罐培养可以明显提高枯草芽孢杆菌的活菌数,为1.86×10~9cfu/mL。发酵液中添加一定量的防腐剂,经长时间保存后枯草芽孢杆菌的存活率均较高,约为95%。     

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.