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[目的]为了提高巨大芽胞杆菌的芽胞形成率及芽胞数量,为巨大芽胞杆菌芽胞制剂的产业化生产提供理论依据。[方法]通过单因子试验及正交试验对巨大芽胞杆菌JD-2发酵培养基和培养条件进行了研究。[结果]最适培养基组成为:玉米淀粉10.0g/L,蛋白胨5.0g/L,酵母膏5.0g/L,NaCl5.0g/L,CaCO31.0g/L,MgSO4·7H2O0.5g/L。确定最佳培养条件为:接种后起始芽胞浓度控制在106CFU/mL,初始pH值为7.0,培养温度为30℃,200r/min摇瓶培养,250mL三角瓶中最适装液体积为25mL。在15L自动发酵罐中扩大培养,控制溶氧在30%以上,培养22h,菌体浓度可达3.50×109CFU/mL,芽胞数量可达3.40×109CFU/mL,芽胞率达97.2%。[结论]试验获得的最佳培养条件可进一步应用于生产实际。 相似文献
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《畜牧与兽医》2016,(10):41-47
饲养蛋鸭时,分别在池水和饮水器中添加光合菌和枯草芽胞杆菌2种益生素,旨在研究益生素联合作用对养殖场水体水质的净化作用。试验采用同一日龄、健康的缙云麻鸭300只随机分成5组,每组3栏,每栏20只。15 d预试期和54 d正试期。试验组Ⅰ:不添加任何微生态制剂;试验组Ⅱ:仅在池水中加20 mg/L光合菌;试验组Ⅲ:饮水中添加125 mg/L枯草芽孢杆菌,池水中添加20 mg/L光合菌;试验组Ⅳ:饮水中添加250 mg/L枯草芽孢杆菌,池水中添加20 mg/L光合菌;试验组Ⅴ:饮水中添加375 mg/L枯草芽孢杆菌,池水中添加20 mg/L光合菌,其中试验组Ⅰ、Ⅱ作为对照组。结果表明:在动物饲养的同时,益生素联用能够在一定程度上降低水中总有机碳、无机碳、总碳、总氮以及总磷的含量,且随饲养时间的增加而增强,而光合菌单独处理的作用效果不佳;无论是单独添加光合菌还是益生素联用对水体中碳氮比的影响较小;试验还表明:益生素联用对水中有机质的降解能力有限,不能有效降解畜禽养殖过程中的粪便持续排放。 相似文献
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本试验以枯草芽孢杆菌和大肠杆菌为供试菌,采用滤纸片法研究辣椒碱对细菌的作用效果。试验一结果显示：辣椒碱对枯草芽孢杆菌、大肠杆菌都有抑菌作用。在浸置3 h时,对于枯草芽孢杆菌,当辣椒碱浓度低于1 mg/mL时,辣椒碱对枯草杆菌的抑菌作用随浓度增加而加强,1 mg/mL时抑菌圈直径达到最大,而浓度大于1 mg/mL时,随浓度增加作用效果减弱|而对于大肠杆菌而言,在浓度为0.125 ~ 3 mg/mL时,辣椒碱的抑菌效果随浓度增加显著加强（P ＜ 0.05）。试验二结果显示：在辣椒碱浓度为1 mg/mL时,对枯草芽孢杆菌的作用效果随浸置时间延长出现降低趋势|而对于大肠杆菌,在同一浸置时间辣椒碱的作用效果为3 mg/mL＞2 mg/mL>1 mg/mL,而对于同一辣椒碱浓度,随着浸置时间延长,作用效果增强。辣椒碱在浓度低于1 mg/mL 时对枯草芽孢杆菌随浓度增加而增强|浓度大于1 mg/mL时,出现减弱趋势|辣椒碱对大肠杆菌抑菌效果在浓度为0.125 ~ 3 mg/mL时随浓度增加而增强,且随浸置时间延长抑菌效果增强。
[关键词] 辣椒碱|枯草芽孢杆菌|大肠杆菌|滤纸片法|作用效果 相似文献
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研究了不同浓度抗生素对农杆菌抑菌效果及对野生黄花苜蓿愈伤组织诱导和分化的影响。结果表明:氨苄青霉素(Amp)的抑菌效果优于头孢霉素(Cef);各个浓度下的Amp和Cef对愈伤组织的诱导与对照相比基本无显著差异;Amp浓度为100～300mg/L,Cef浓度为200～500mg/L时对不定芽的形成具有较好的促进作用。因此,在进行农杆菌介导黄花苜蓿遗传转化研究时,可选择Amp作为抑菌剂,最佳浓度为300mg/L;Kan和Hyg作为抗性愈伤选择剂,适宜的浓度分别为40～50mg/L和15～20mg/L。 相似文献
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为进一步鉴定、分析和评价分离于鸡粪便的13株芽胞杆菌,根据枯草芽胞杆菌16 S rRNA 序列设计特异性引物,PCR 扩增13株分离于鸡粪便的芽胞杆菌,将扩增片段测序并分析同源性;将鉴定的枯草芽胞杆菌进行耐酸、耐胆盐、耐高温等试验,同时用不同剂量菌液分别以不同方式感染小鼠,定期称重、观察各脏器病理变化和计算主要脏器系数。结果显示,Q04、Q05、Q09与 GenBank 公布的枯草芽胞杆菌16 S rRNA 序列同源性为99％,且 Q04在 pH2．5,胆盐浓度2 g／L 以及100℃时生长良好;感染小鼠全部健康存活,体重均有增加;小鼠脏器无病变,脏器系数无显著差异（P ＞0．05）。由结果可知,分离鉴定菌株 Q04、Q05、Q09为枯草芽胞杆菌,其中 Q04具有更好的生物学特性,并且对小鼠安全无毒,可作为微生态制剂的候选菌株。 相似文献
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试验以柿子为基料,对l株枯草芽胞杆菌的发酵培养基进行了优化。结果表明,成熟柿子匀浆100g/L、大豆粉20g/L,接种量5％,37℃培养24h,活茵数可达4．7×1010cfu／mL。 相似文献
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将240只1日龄罗斯(ROSS 308)肉鸡分为4个组:处理组1(对照组)饲用基础日粮+金霉素,处理组2饲用基础日粮+枯草芽胞杆菌,处理组3饲用基础日粮+丝兰提取物,处理组4饲用基础日粮+丝兰提取物和枯草芽胞杆菌,以研究丝兰提取物和枯草芽胞杆菌对肉鸡生长性能的影响,试验期42 d。结果:平均日增重和料重比指标,处理组4肉鸡显著优于处理组1(P<0.05),而处理组2和3之间无显著差异(P>0.05)。肉鸡21日龄时,处理组4肉鸡血清白蛋白浓度显著大于处理组1;处理组4血清尿酸浓度显著小于处理组1。42日龄时,处理组2和4肉鸡的血清白蛋白浓度显著大于处理组1。本试验证明丝兰提取物与枯草芽胞杆菌均能提高肉鸡对饲料蛋白的代谢利用率,且具有协同改善肉鸡生长性能的效果。 相似文献
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两种抗生素的效价比及其对甘农3号紫花苜蓿愈伤组织生长发育的影响 总被引：3，自引：3，他引：3
两种抗生素羧苄青霉素和头孢霉素对农杆菌LBA4404的抑菌效果及其对甘农3号紫花苜蓿愈伤组织的生长、体细胞胚分化的影响进行了研究。结果表明,羧苄青霉素的抑菌效果较好,适宜浓度为200~300 mg/L;在浓度200~400 mg/L的羧苄青霉素可促进芽分化;头孢霉素对甘农3号下胚轴离体培养的毒性大,浓度为600 mg/L时完全抑制芽分化。因此,羧苄青霉素为适宜抑菌剂,愈伤诱导阶段的适宜浓度为300 mg/L,体胚形成及芽诱导分化阶段的适宜浓度为200 mg/L。 相似文献
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《黑龙江畜牧兽医》2018,(23)
为了探讨重金属铅(Pb)对金盏菊(Calendula officinalis)种子萌发及幼苗生长的影响,试验分别设置7个浓度[T0(CK)、T1(5 mg/L)、T2(10 mg/L)、T3(20 mg/L)、T4(30 mg/L)、T5(50 mg/L)、T6(80 mg/L)]的铅离子(Pb~(2+))处理溶液,对金盏菊种子进行胁迫,并进行了发芽试验,分别测定了种子的发芽率、发芽势、发芽指数及根系生长情况。结果表明:低浓度的Pb~(2+)胁迫对金盏菊种子的发芽率、发芽势及发芽指数产生一定的促进作用(P0.05),当Pb~(2+)浓度为20 mg/L时促进作用最强烈;当Pb~(2+)浓度高于20 mg/L时胁迫促进作用开始逐渐减弱;Pb~(2+)胁迫对金盏菊根长无明显作用(P0.05);Pb~(2+)胁迫对幼苗根部横截面积存在一定的抑制作用;金盏菊种子对bp~(2+)的耐受性较强。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
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。 相似文献
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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。 相似文献
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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。 相似文献
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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. 相似文献
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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. 相似文献