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随着科学技术的不断创新,通讯事业飞速发展,千家万户都安上了电话,家畜繁育改良工作也由过去在繁育中心坐家配种转变为主动到农户家中服务,母畜保定就成了当前比较棘手的问题.为了解决母畜保定问题,我们采用了以下几种方法仅供参考. 相似文献
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二十世纪前半期一、意大利蜂的引入1903￣1920年,西方蜂种(主要是意蜂)及新养蜂法先传入福建、广东、香港、天津、北京等地,不久也传入黑龙江省。民国初年的养蜂情况《珠河县志》有以下记载:"民国初年,西洋蜂种及养蜂法传来以后, 相似文献
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(一)病因类型 1.消化不良型:母猪产前精料喂的过多,或突然更换饲料,加重胃肠负担,引起消化不良.此病常发于分娩之后,体温正常,食欲不振,粪便先干后稀,有的病猪喜欢喝点成汤,有的吃点鲜块茎和生米等食物,但数量不大,严重者食欲废绝. 相似文献
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随着年关临近，为了确保产区农民收入稳定增长，近日，政府有关部门出台了东北储备粮收购计划。在该重大利好政策拉动之下，我国部分产区玉米价格有望触底反弹，但受市场供应依然充足、需求整体依旧偏弱影响，国内玉米市场行情涨跌两难，具体分析如下： 相似文献
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<正>河南省地处黄河中下游，蚕业生产历史悠久。建国50年以来，尤其是近20g间，经过“七·五”至“八·五”的迅速发展和“九·五”、“十·五”的稳步调整，河南蚕业生产规模基本稳定，生产水平得到提高。目前全省桑园面积1．67万hm~2，年产桑蚕茧6000t，与建国时相比，桑园面积和蚕茧产量分别增长了24倍和42．2倍，与改革开放初期的1978年相比，分别增长了2．25倍和4．18倍；蚕业深加工等综合产值达到10亿元，农民收入达5亿元，出口创汇8600多万美元。“九·五”、“十·五”期间，河南茧丝绸业保持着北方诸省(山东、陕西省除外)生产、出口主要基地和传统优势产业、出口创汇大户的地位。蚕业生产已成为不少平原和山区农民脱贫致富奔小康的支柱产业。 1 “九·五”、“十·五”实际生产情况 1．1 实际生产情况 1．1．1 生产规模保持基本稳定桑蚕生产在经历了1995年“全面下滑”桑园规模大幅度缩减后，“九·五”期间，全省蚕茧的总产和年产量也相应减少，但集中产 相似文献
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夏秋季节龟活动较多,或运输中腹甲损伤,或池子粗糙引起磨损龟甲后而导致龟甲内局部红肿发炎,多数常见于腹甲内部有出血斑块,并向四周浸润扩散,严重时可波及整个龟甲,引起败血症而死亡.池中水质差、消毒少、水底氧气少时易产生大量单孢杆菌是引起此病的元凶. 相似文献
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为获得牛支原体（Mycoplasma bovis,M.bovis）VspX蛋白单克隆抗体,将编码该蛋白的基因克隆、表达并纯化,作为免疫原,以QuickAntibody-Mouse 5W为免疫佐剂,免疫BALB/c小鼠。经3次免疫后,将小鼠脾细胞与SP2/0骨髓瘤细胞融合,经3次亚克隆筛选后,共获得5株能稳定分泌抗VspX蛋白抗体的杂交瘤细胞株,分别命名为1A8、3A3、3C12、3H9及4D11。亚型鉴定表明,3C12重链为IgG2b,其余4株为IgG1,轻链均为κ链。间接ELISA结果表明,5株细胞培养上清的抗体效价在1：1×104~1：2×105,腹水效价在1：1×105~1：8×105。选其中两株杂交瘤细胞株3H9和4D11的腹水纯化,进行亲和力测定,解离常数分别为6.3×109和7.8×109,属高亲和力抗体。Western blotting结果显示,5株单抗均能与牛支原体发生特异性反应,而单抗4D11与羊无乳支原体标准株PG2和丝状支原体丝状亚种标准株PG3均不反应。流式细胞术结果表明,单抗4D11与牛支原体表面的VspX的结合呈剂量依赖性。间接免疫荧光结果表明,单抗4D11可以识别黏附到胚胎牛肺细胞上的重组VspX蛋白。本试验成功制备的单克隆抗体为VspX蛋白功能的研究奠定基础。 相似文献
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To obtain the monoclonal antibody (McAb) against VspX protein of Mycoplasma bovis (M. bovis),VspX gene was amplified, expressed and purified. Then, BALB/c mice were immunized subcutaneously three times with the purified recombinant VspX (rVspX) mixed with QuickAntibody-Mouse 5W adjuvant. Three days after the last injection, spleen cells were collected aseptically, and fused with SP2/0 myeloma cells in the presence of polyethylene glycol. By the clone selection, five stable hybridomas against VspX protein were obtained, separately named as 1A8, 3A3, 3C12, 3H9 and 4D11. Antibody titers in cell supernatant were from 1:1×104 to 1:2×105, while from 1:1×105 to 1:8×105 in ascites of mice by indirect ELISA. The subtypes were determined to be IgG1 and IgG2b class, and all light chains were κ chain. The affinity constant of McAb 3H9 and 4D11 were 6.3×109 and 7.8×109, respectively, and they belonged to high-affinity antibodies. Western blotting results showed that all of five McAbs could specifically react with M.bovis, however, McAb 4D11 could not react with Mycoplasma arginini PG2 and Mycoplasma mycoides subsp. PG3. Flow cytometry showed that McAb 4D11 reacted with surface VspX of M. bovis in a dose-dependent manner. Indirect immunofluorescence assay demonstrated that 4D11 McAb was able to detect rVspX protein binding to embryonic bovine lung cells. In the present study, McAbs against rVspX protein had been successfully prepared, which provided a basis for future researches about the function of VspX protein and the pathogenesis of M. bovis. 相似文献
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ZHANG Wei WANG Xing LIU Jin-ping XU Sheng-le QIN Hai-yan LIU Ruo-xuan CAI Yun-hong RU Xiao-fei HOU Ke WANG Han-dong 《中国畜牧兽医》2017,44(4):1159-1167
The aim of the study was to prepare a monoclonal antibody (McAb) against cephalexin(CEX),and preliminarily establish an ELISA method to detect residues of CEX in milk. The CEX was conjugated to carrier bovine serum albumin (BSA) and ovalbumin (OVA) by two-step glutaraldehyde method. BALB/c mice were immunized with the prepared CEX-BSA conjugate. After five times immunization, we built and screened two strains of hybridoma cells (2G4 and 5B3) which secreted McAb against CEX by hybridoma technology.The 2G4 cell lines were injected into BALB/c mouse's abdominal cavity to produce ascites. Finally the ascites were purified and identified. The results showed that antibody titer of the McAb 2G4 was above 1∶1.28×105,its antibody subtype was IgG2b(κ) and affinity constant K was 1.51×109 L/mol. The cross experiment result evidenced that the cross reaction rate of cefradine was 52.55%, ceftiofur, ceftriaxone, cefotaxime, cephalothin, penicillin, streptomycin and tetracycline had no cross reaction. We established an ELISA method to detect CEX residues in milk and its linear range was 20 to 1 000 ng/mL, linear equation y=0.4674x-0.5359(R2=0.9909), its limit of detection (LOD) was 19.68 ng/mL and the average recovery rate was 91.31%, the average coefficient of variation was below 15%. The detection limit was lower than the maximum residue limit of cefalexin in China and European Union. So this detection method might have good application foreground. 相似文献
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为制备抗头孢氨苄（cephalexin,CEX）的单克隆抗体并建立鲜奶中CEX残留检测的ELISA方法,本试验采用戊二醛两步法分别将CEX与牛血清白蛋白（BSA）、卵清白蛋白（OVA）偶联,用合成的CEX-BSA作为免疫原免疫BALB/c雌鼠;5次免疫后,应用杂交瘤细胞融合技术建立并筛选出两株（2G4、5B3）分泌抗CEX单克隆抗体（monoclonal antibodies,McAb）的杂交瘤细胞株,将2G4细胞株注入BALB/c小鼠腹腔制备腹水,并对腹水进行纯化及鉴定。结果显示,2G4腹水效价大于1∶1.28×105,其抗体亚型为IgG2b（κ）,亲和力常数K=1.51×109 L/mol;交叉试验结果显示,该单克隆抗体除了与头孢拉定有52.55%的交叉反应率外,与头孢噻呋、头孢曲松、头孢噻肟、头孢噻吩、青霉素、链霉素、四环素均无明显交叉反应;建立了测定鲜奶样品中CEX的ELISA方法,线性范围为20~1 000 ng/mL,线性方程y=0.4674x-0.5359（R2=0.9909）,检测下限为19.68 ng/mL,平均回收率为91.31%,平均变异系数低于15%,低于中国及欧盟规定的头孢氨苄最高残留限量,具有一定的应用前景。 相似文献
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In this test,BALB/c mice were immunized by SW-OVA for the preparation of monoclonal antibody against swainsonine (SW). Hybridoma cells that could secrete specific antibody against SW were prepared by hybridoma technique,and then the strain that secreted monoclonal antibody against SW designated 1F10 was prepared,and the chromosome average number of 1F10 cell was 45 to 50 couples. The ELISA titers of cell supernatant were 1:25 600, and that of ascites were 1:80 000.The subclasses of monoclonal antibody was IgG1,and the affinity constant was 1.14×1010,the purity of ascites antibodies was up to 98%,and the recovery rate was 80%.The result of sodium dodecyl sulfate polyacrylamide gel electropheresis proved that purified antibody had been obtained that the molecular weight of H-chain and L-chain of antibody was about 50 and 25 ku. The monoclonal antibody against SW specifically bound to SW determined by Western blotting. The linear range was 4 to 128 μg/mL (R2=0.9969) and no cross-reactivity was detected with BSA,gelatin,polylysine,me-Gal,etc. The result laid the foundation for immunodetection on SW and immunological prevention of animal toxic disease. 相似文献
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本试验采用苦马豆素（swainsonine,SW）人工抗原SW-OVA免疫接种BALB/c小鼠,通过杂交瘤技术建立了1株能稳定分泌SW单克隆抗体的杂交瘤细胞1F10,杂交瘤细胞染色体数目为45~50对。经间接ELISA检测,该株细胞培养上清中抗体效价为1：25 600,诱生腹水效价为1：80 000。单克隆抗体的亚型为IgG1,亲和力解离常数为1.14×1010,腹水抗体纯化后纯度可达98%,回收率80%,SDS-PAGE凝胶电泳可见单克隆抗体的轻链、重链分子质量分别为25和50 ku,Western blotting检测抗体能特异性的识别SW。其线性检测范围为4~128 μg/mL（R2=0.9969）,与BSA、明胶、多聚赖氨酸、α-甘露糖苷等无交叉反应。本试验制备的SW单克隆抗体为免疫学检测SW和免疫学防制家畜疯草中毒奠定基础。 相似文献
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XUE Fei YANG Zichun XU Yanhui WANG Yaling YU Ting FAN Maodi LIU Juanhua GAO Song LIU Xiufan 《畜牧兽医学报》1956,51(12):3122-3132
To development monoclonal antibodies against cOmpT of avian pathogenic Escherichia coli (APEC), the recombinant cOmpT of APEC origin expression plasmid pET-28a-compT was employed, and cOmpT protein with a molecular weight about 36 kD in the form of inclusion bodies was obtained after induction with IPTG, and then renatured by urea gradient dialysis. BALB/c mice were immunized with the purified cOmpT. An indirect enzyme-linked immunosorbent assay (iELISA) was developed, the optimal coating concentration of the antigen was 0.625 μg·mL-1 and the optimal serum dilution was 1:6 400. After the fourth immunization, the spleen of immunized mice was collected for cell fusion, three monoclonal hybridomas that can secrete antibody specific to cOmpT were obtained after multiple screenings, named 1G8, 2C3 and 2G3 respectively. And all of their immunoglobulin subclasses were IgG2b. The titers of monoclonal antibodies in the cell culture supernatant were 1:200, 1:3 200 and 1:3 200 determined by iELISA, respectively. All three monoclonal antibodies were confirmed to react with cOmpT in Western blot, without cross reaction with other tested bacteria. The antigenic epitopes recognized by the three monoclonal antibodies were identified by using a series of E. coli strains harboring expression plasmids recombined with truncated fragments from compT gene. The results revealed that the antigenic epitope required for reactivity with the 1G8 was 83DQDWMDS89, and 90SNPGTW95, 197TFKYSGW203were recognized by 2C3 and 2G3, respectively. In this study, three monoclonal antibodies against cOmpT were successfully developed and the antigenic epitopes recognized by the antibodies were identified. The cOmpT specific monoclonal antibodies obtained in this study are potentially useful tools for both the functional study of cOmpT and the development of APEC epitope vaccines. 相似文献
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旨在制备禽致病性大肠杆菌（APEC）染色体编码外膜蛋白（cOmpT）的特异性单克隆抗体，本研究利用实验室已构建的APEC cOmpT重组表达质粒pET-28a-compT，经IPTG诱导表达后，获得以包涵体形式存在的约36 ku的重组蛋白cOmpT，利用尿素浓度梯度透析复性获得纯化蛋白cOmpT，并以此免疫BALB/c小鼠。建立间接ELISA检测方法，最适抗原包被浓度为0.625 μg·mL-1，最适血清稀释度为1：6 400。4次免疫后取小鼠脾进行细胞融合，采用有限稀释法多轮筛选后得到3株能稳定分泌针对cOmpT蛋白的单克隆抗体，分别命名为1G8、2C3和2G3，均为IgG2b亚类。3株杂交瘤细胞上清ELISA抗体效价分别为1：200、1：3 200和1：3 200。Western blot结果显示，3株单抗均能与cOmpT发生特异性反应，而不与其他受检菌发生交叉反应。运用原核表达系统对compT基因进行截短表达，对单克隆抗体针对的cOmpT抗原表位进行鉴定，结果显示单抗1G8、2C3和2G3识别的抗原表位分别是83DQDWMDS89、90SNPGTW95和197TFKYSGW203。本研究成功制备了3株抗cOmpT蛋白的单克隆抗体，并对其识别的抗原表位进行了鉴定，为cOmpT蛋白功能研究和APEC新型表位疫苗研发奠定了基础。 相似文献
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WANG Leming WANG Yurui ZENG Zixuan RAO Guoshun WU Zhengjiao JIN Weikun WANG Dongying 《中国畜牧兽医》2022,49(2):677-686
【Objective】 This study was intend to obtain cathepsin L1(rFgCat L1) specific monoclonal antibody and construct the double antibody sandwich ELISA.【Method】 Five BALB/c mice were immunized with 1 mg/mL rFgCat L1 protein for four times.Mouse splenocytes were isolated and fused with SP2/0 cells to construct hybridoma cells.Strong positive hybridoma cell lines were screened, 1×106 cells were injected intraperitoneally per mouse to prepare monoclonal antibodies.Antibody titer and antigenic epitope were detected using ELISA method, antibody subtype and specificity were identified using Western blotting method.The double antibody sandwich ELISA was constructed by combining the anti-rFgCat L1 polyclonal antibody, and its sensitivity and specificity were tested.The positive and negative critical value was screened by 20 negative sera with positive control, and the constructed double antibody sandwich ELISA was verified by 47 goat positive sera and 47 dairy cow positive sera.【Result】 After immunization, the antibody titers in serum of 4 mice were all more than 104.After isolated mouse with the highest immune response spleen cells were fused with SP2/0 cells total of 8 of them were positive cell lines were obtained after selective culture.5D5 and 7G6 were identified as strong positive strains with stable antibody secretion.After multiple subcloning screens and subcultures, the antibodies secreted in the cell supernatant were stable, with titers of 29 and 210 respectively, with ascites titers of 107 and 108.Western blotting and antibody subtype identification kits identified that the two antibodies were IgG1 type and the light chain was kappa type, both of which could specifically bind FgESP.According to the same antigen site was recognized by the two kinds of antibodies, the antigen titer of the two monoclonal antibodies were comparied, 7G6 was used as the coating antibody, and anti-rFgCat L1 was used as the enzyme-labeled secondary antibody.The optimized condition of method was that 7G6 was coated at a concentration of 2 μg/mL, the dilution concentration of anti-rFgCat L1 polyclonal antibody was 25 μg/mL, the dilution of Don-HRP-conjugated was 1∶4 000, 5% skimmed milk powder was selected as the blocking solution and the color development time was 25 min.The method was proved that could recognize the lowest antigen concentration of 0.625 μg/mL, also could specifically recognize antigen of Fasciola fasciatus.The constructed sandwich ELISA method was used for antigen detection of 47 dairy cow positive serum and 47 goat positive serum infective samples kept in the laboratory and the positive antigen rate were 72.3% and 78.7%, respectively.【Conclusion】 Anti-rFgCat L1 monoclonal antibody was successfully prepared and the double-sheet sandwich ELISA method for fascioliasis was constructed, which provided a good theoretical basis and material basis for the development of low-cost and rapid diagnostic kits. 相似文献
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FU Qiu-ling LIU Wei HUANG Yu FU Guang-hua WAN Chun-he CHENG Long-fei CHEN Hong-mei SHI Shao-hua LIU Rong-chang CHEN Zhen CHEN Cui-teng LIN Jian-sheng 《中国畜牧兽医》2017,44(2):554-560
To prepare the monoclonal antibodies (MAbs) against DHAV-1a, hybridomas were produced by fusing SP2/0 cells with spleen cells from mouse immunized with DHAV-1a pGEX-VP1 recombinant protein. Two hybridomas stablely secreting MAbs against VP1 protein were identified by indirect ELISA detection with DHAV-1a as coating antigen. The ascetic fluids of MAbs were 1:3.2×104 and 1:2.0×106, respectively. The MAbs were IgG1 with κ chain. Western blotting analysis showed that the MAbs could recognize the recombinant VP1 protein and DHAV-1a. The neutralization tests showed that one MAb (5G3) had better neutralization activity. Therefore, the results showed that the ELISA titers and specialities of two MAbs were very good, with excellent stability. In addition, they all had cross interaction with DHAV-1 and DHAV-1a, one of which had good neutralization activity. 相似文献