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黄瓜全雌性基因连锁的AFLP和SCAR分子标记   总被引:32,自引:5,他引:32  
 本研究以全雌品种‘戴多星’自交系和弱雌品种‘北京截头’自交系为双亲杂交获得F1 ,然后得到F2 性型分离群体, 利用分离群体分组分析法(Bulked Segregant Analysis, BSA) 构建全雌和弱雌两个基因池, 筛选了64对AFLP选择性引物EcoR I-NN +Mse I-NNN组合, 发现EcoR I-TG +Mse I-CAC引物组合在全雌基因池中扩增出一条分子量为234 bp的特异带。经F2 代单株验证, 该特异条带能在全雌单株中稳定出现。以MAP MAKER (Version 310) 软件分析, 该标记与全雌性位点的连锁距离在617 cM。命名该连锁标记为TG/CAC234。将该特异条带回收、克隆、测序, 设计特异SCAR引物, 再对F2 代单株基因组DNA进行扩增, 仅在全雌单株中扩增出1条分子量为166 bp 的特异带, 表明已成功地将与黄瓜全雌性连锁的AFLP标记转化为操作简便、表现稳定的SCAR标记, 该标记命名为SA166。  相似文献   
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ObjectiveTo quantify induction time, reliability, physiological effects, recovery quality and dart volume of a novel formulation of alfaxalone (40 mg mL?1) used in combination with medetomidine and azaperone for the capture and handling of wild bighorn sheep.Study designProspective clinical study.AnimalsA total of 23 wild bighorn sheep (Ovis canadensis) in Sheep River Provincial Park, AB, Canada.MethodsFree-ranging bighorn sheep were immobilized using medetomidine, azaperone and alfaxalone delivered with a remote delivery system. Arterial blood was collected for measurement of blood gases, physiologic variables (temperature, heart and respiratory rates) were recorded and induction and recovery length and quality were scored.ResultsData from 20 animals were included. Administered dose rates were alfaxalone (0.99 ± 0.20 mg kg?1; 40 mg mL?1), azaperone (0.2 ± 0.04 mg kg?1; 10 mg mL?1) and medetomidine (0.16 ± 0.03 mg kg?1; 30 mg mL?1). The mean drug volume injected was 1.51 mL. The median (range) induction time was 7.7 (5.8–9.7) minutes, and recovery was qualitatively smooth.Conclusions and clinical relevanceAn increased concentration formulation of alfaxalone was administered in combination with medetomidine and azaperone, and resulted in appropriate anesthesia for the capture and handling of bighorn sheep. The dart volume was small, with potential for reducing capture-related morbidity.  相似文献   
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Dioxathion residues in milk (expressed as the sum of the cis and trans isomers) have been determined by gas liquid chromatography using the N-P thermionic detector. It was found that dioxathion residues of 0.06 to 2.29 ppm (fat basis) are present in milk and are associated with tick control procedures of spraying cows with 0.05% w/v dioxathion (Delnav) twice weekly. Average concentrations from bulked milk were 0.96 ppm after 10 hours, 0.54 ppm after 34 hours and 0.4 ppm after 58 hours following spraying. The levels of residues in the milk differed greatly in different animals.  相似文献   
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In this paper we report on an outbreak of reovirus, herpesvirus (Pacheco disease), and/or mycosis infection (Aspergillus spp. and Zygomyces spp.) affecting a batch of young African grey parrots (Psittacus erithacus), with 80% morbidity and 30% mortality. Study material was taken from five birds (four dead and one euthanatized) with a range of clinical symptoms (depression, diarrhea, respiratory symptoms). Diagnosis was confirmed by immunohistochemical detection of avian reovirus, electron microscopy, and virus isolation. Viral antigen of reovirus was detected mainly in large mononuclear cells in the bursa of Fabricius and the spleen, pancreas epithelial cells, and circulating cells; lymphoid organs displayed the largest number of immunopositive cells and severe lymphocyte depletion. Bacteriologic study was negative. Reovirus infection was common in all birds studied, whereas Pacheco disease and mycosis were found in only some, suggesting that reovirus could be the initial cause triggering the outbreak and facilitating infection by other agents and their swift spread through the batch.  相似文献   
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