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概述了昆虫信息激素的种类。着重就桑蚕信息激素(桑蚕醇、桑蚕醛)的结构和理化性质,信息激素的感受机制,电生理反应和嗅觉感受的学说,以及对桑蚕信息激素的扩散和雄蛾最终找到雌蛾的机制作了论述。  相似文献   

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引言 工业配合饲料产业是动物源食品产业链的重要一环,良好管理规范对于生产安全饲料和安全食品这一产业链的每个阶段--从上游生产到最后加工阶段的都至关重要.因此,饲料和食品链的生产企业有责任推行良好的操作规范以确保所生产的产品安全性.  相似文献   

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抗CP型、NCP型牛病毒性腹泻病毒高免卵黄抗体的制备   总被引:1,自引:0,他引:1  
本研究采用致细胞病变(cytopathic,CP)型牛病毒性腹泻病毒(bovine viral diarrhea virus,BVDV)标准毒和非致细胞病变(noncytopathic,NCP)型新疆优势毒株免疫产蛋鸡,用改良PEG法提取卵黄抗体(IgY),并对提取的IgY采用SDS-PAGE检测纯度,间接ELISA检测免疫后每隔7 d的抗体效价,并测定所得抗体对NCP型BVDV的中和效价。结果表明,用该法提取的IgY纯度较高;间接ELISA结果证明,经过4次免疫后,抗CP型BVDV的效价达到1∶32000,抗NCP型BVDV的效价达到1∶40000,3个月后再次检测,卵黄抗体效价未见明显下降。最后一次免疫14 d的抗体对NCP型BVDV的中和效价达到1×10-3。  相似文献   

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以新城疫病毒(NDV)LaSota株为免疫原研制了3株针对NDVHN蛋白的单抗,分别命名为1E5、C3-B7和E6-F11。3株单抗与NDV不同毒株在血凝抑制试验(HI)、ELISA和病毒中和试验中的反应性不同,而同一株单抗与同一个NDV毒株在HI、ELISA以及病毒中和试验中的反应性一致。其中,单抗1E5与NDV标准株(LaSota、F48E8)、8个NDV分离株反应阳性,而与9个NDV分离株反应阴性;单抗C3-B7、E6-F11与所有NDV毒株反应均为阳性。结果表明,3株单抗均是针对HN蛋白上的中和位点,国内部分NDV流行株的HN抗原至少有1个抗原位点发生了变异。  相似文献   

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生长抑素抑制剂--半胱胺的研究进展   总被引:8,自引:0,他引:8  
由神经系统和胃肠道产生的生长抑素(Somatostain,SS)对动物的生长激素、甲状腺素、胰岛素等代谢激素起抑制性调节作用。添加外源半胱胺(Cysteamin,CS)能迅速选择性地降低动物体内中枢及外周生长抑素的生物活性与免疫活性,提高生长激素(Growth hormone,GH)水平,加强消化道的蠕动和消化酶的分泌,从而起到促进动物生长和改善生产性能的功能。  相似文献   

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Three field trials were conducted over 12 months to assess the pathogenicity of Metarhizium anisopliae to parasitic stages of Rhipicephalus (Boophilus) microplus on dairy heifers under different environmental conditions. Two isolates were selected based on their high optimal growth temperature (30 degrees C), good spore production characteristics and ability to quickly kill adult engorged ticks in the laboratory. Spores were formulated in an oil emulsion and applied using a motor driven spray unit. Surface temperatures of selected animals were monitored, as were the ambient temperature and relative humidity. Unengorged ticks sampled from each animal immediately after treatment were incubated in the laboratory to assess the efficacy of the formulation and application. Egg production by engorged ticks collected in the first 3 days after treatment was monitored. Side counts of standard adult female ticks were conducted daily, before and after treatment to assess the performance of the fungus against all tick stages on the animals. In each trial the formulation rapidly caused 100% mortality in unengorged ticks that were removed from cattle and cultured in the laboratory. A significant reduction in egg production was recorded for engorged ticks collected in the 3 days post-treatment. However, there was little effect of the formulation on the survival of ticks on cattle, indicating that there is an interaction between the environment of the ticks on the cattle and the biopesticide, which reduces its efficacy against ticks.  相似文献   

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在传染性喉气管炎病毒北京E2株TK基因克隆,鉴定的基础上,进一步构建转移载体质粒,为ILTV TK基因缺失毒株的构建作准备,先用PstI将pSV-gal线性化,再经EcoRi不完全酶切,分离含SV40立即早期启动子和增强子的4.2Kb的LacZ报告基因片段,并用Klenow大片段补平,将克隆TK基因的载体pTK用SnaBI处理,后用T4DNA连接酶将以上两个片段平端连续成重组质粒,转化 JM109  相似文献   

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上接2003,342:96信息激素的电生理反应Schneider(1956、1957、1959)曾详细地研究了桑蚕雄虫触角对于性外激素(蚕醇)的电生理效应。他们用刚切下的一段触角,插入一个微小的、涂氯化银的电极,通过一个放大器连接到一个示波器上,记录下触角在受雌虫性外激素(及其他化合物)的作用下的作用电位。这个典型的反应就是触角电位图(Electroan-tennogram简称EAG),而其它的嗅觉刺激物或药品则引起不同形状的EAG。EAG的振幅和该引诱剂的浓度直接相关。当嗅觉刺激物是雌性蚕蛾性引诱剂的提取物时,在雄蛾触角中的电活性提高,但在雌蛾中则没有。当刺激…  相似文献   

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Six mule deer (Odocoileus hemionus) with dermatomycosis are described. Trichophyton verrucosum was isolated from four. All infections were mild and were not debilitating. The lesions involved the legs in five animals and the face in two. This is the second report of ringworm in a wild ungulate in North America.  相似文献   

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大肠杆菌肠毒素ST1-LTB融合基因的高效表达   总被引:13,自引:0,他引:13  
用限制性核酸内切酶EcoRⅠ和HindⅢ双酶切含大肠杆菌肠毒素ST1—LTB融合基因的质粒pXSLT1,回收084kb的ST1—LTB融合基因,再将载体pET—28b(+)用EcoRⅠ和HindⅢ双酶切,然后将其与ST1—LTB融合基因连接,转化至受体菌BL21(DE3)中。经EcoRⅠ、HindⅢ、BamHⅠ酶切反应鉴定重组子质粒,得到了理想重组质粒pXETSLT1。重组菌株BL21(DE3)(pXETSLT1)经IPTG诱导后,其表达产物经SDS—PAGE和ELISA检测,结果表明重组菌株可以高效表达ST1—LTB融合蛋白,该融合蛋白占菌体总蛋白的3321%,而且无天然ST1生物毒性。  相似文献   

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The first case of Entamoeba of the 1-nucleate mature cyst group in birds is described. Trophozoites and cysts of Entamoeba have been found in ostriches (Struthio camelus) from farms located all over Spain. The cysts are large (13.47microm mean diameter); they possess one nucleus when mature, with a large endosome and peripheral chromatine arranged in small granules; chromatoid bodies, when present, are large and elongated. Trophozoites are large (19. 88microm mean diameter), with a clear differentiation between ecto- and endoplasm, this containing numerous vacuoles; the nucleus is large and diffuse. The characteristics of this amoeba resembles but do not completely fulfill those of E. suis and E. chattoni; also, these species are from mammals.  相似文献   

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The time periods and the behavioural pattern of mink euthanized with carbon dioxide (CO2), 100% and 70%, carbon monoxide (CO), 4%, and nitrogen (N2), 100%, are described. The time between the placement of the animal in a glass box and the first symptoms of incoordination (phase I), the period of loss of consciousness (phase II), and, finally, the coma phase until cessation of respiration (phase III) using three groups each of 10 pastel male mink each were recorded. Phase I times ranged from 14 s for CO2, 31 s for N2, and 49 s for CO. In phase II, the difference was even more pronounced, being 5 s for CO2, 15 s for CO, and 45 s for N2. In phase III, the time was 58 s for N2, 134 s and 151 s for CO2 and CO respectively. Hence, the critical period from the time when the animals were placed in the glass box till unconsciousness occurred (phase I and II) was 19 s for CO2, 64 s for CO, and 76 s for N2. The total course of euthanasia was 153 s for CO2, 215 s for CO, and 134 s for N2. The following minimum times will be required before it can be judged to be safe to remove the animals: CO2 and N2: 5 min, and for CO: 6.5 min. In a supplementary experiment, involving a mixture of 70% CO2 and 30% atmospheric air, it was not possible within the allotted time to kill adult male mink.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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Roper (2020) conducted a critique of the Larson et al. (2019) study of the accuracy and confidence of data collected using systematic and random sampling designs.   Roper (2020) did not provide a data set but speculated that the Larson et al. (2019) conclusions likely reflected differences in the number of plants evaluated at each plot and the low number of independent observers rather than the sample design.  Our random sampling design employed multiple randomly located quadrat locations and measured multiple plants (> 5) that were averaged within the plot to represent plot characteristics.  Data collected in this fashion fulfilled assumptions intrinsic to and necessary for statistical analysis using plot data as observations.  Thus, the statistical observations reported in the original paper are valid.  相似文献   

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柑橘大实蝇是柑橘生产的重大害虫,目前柑橘大实蝇疫情呈逐年加重趋势,特别是“蛆柑事件”(大实蝇幼虫)给广大橘农造成了巨大的经济损失,严重制约了柑橘产业的健康发展。本文论述了柑橘大实蝇的形态特征、发生规律、传播途径和综合防控措施。  相似文献   

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