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Abstract. The feasibility of including individual records on correlated traits in a family selection programme which aims to increase resistance to furunculosis in Atlantic salmon was studied; markers were selected because of their potential role in the pathogenesis of the disease. Fibrinogen and α2 -antiplasmin both show genetic variation; both are correlated with survival after challenge with Aeromonas salmonicida , the correlation being 0·44 and 0·37 ( P < 0·05), respectively, and it is possible to measure both on a large scale at low costs. Contrary to α2 -antiplasmin, fibrinogen was negatively correlated with survival due to furunculosis within the 10 most resistant families and within the 10 most susceptible families in contrast to an overall positive correlation. This inconsistency could be attributable to the presence of different allelic phases in different families, and of major linked loci influencing survival and fibrinogen levels. Thus, only α2 -antiplasmin fulfils the requirements for a marker trait for resistance to the disease suitable for individual selection at the population level, whereas the use of fibrinogen would be restricted to within family selection. The full statistical model explained 51% of the variation in resistance to furunculosis, and α2 -antiplasmin contributed 15% to this variation when considered as a separate entity. Thus, the additional gain from including individual records on α2 -antiplasmin in a family selection programme could be significant. 相似文献
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基于改进Bayes抠图算法的麦穗小穗自动计数方法 总被引：1，自引：1，他引：0
小麦产量评估需人工获取田间单位面积的麦穗数和麦穗小穗数，往往耗时耗力。为了实现高效、自动地麦穗小穗计数，提出一种基于改进Bayes抠图算法的麦穗小穗自动计数方法。该方法首先利用改进Bayes抠图算法对获取地自然生长条件下的麦穗图像进行抠图，将麦穗从自然背景中分割出来。然后对该图像进行平滑滤波和二值化，运用迭代极限腐蚀运算对二值化图像进行腐蚀处理，去除麦穗图像中的麦芒，分离出麦穗上每个单独的麦穗小穗。再运用面积滤波滤除掉面积过小的区域，对剩余区域的黑洞进行填充，由此每个单独的麦穗小穗形成一个单独的连通区域，最后对连通区域进行标记和计数，完成麦穗小穗的自动计数。使用4个小麦品种的麦穗图像对麦穗上的小穗进行计数验证，结果表明，该方法在识别4个品种田间麦穗单幅图像中小穗数量的平均计数精度达到94.53%，平均相对误差为5.47%，对比已有麦穗小穗自动计数方法，计数精度显著提高，这对于小麦在线产量预估具有重要意义。 相似文献
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在系统可编程技术将数字系统的设计过程由书面设计──硬件搭配──制做样机改变为书面设计──仿真──制做样机,避免了搭试的诸多弊端。其关键环节仿真,是计算机发展和可编程器件使用的共同结果。 相似文献
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B. SAN MARTIN J. CORNEJO L. LAPIERRE D. IRAGÜEN F. PÉREZ H. HIDALGO F. ANDRE 《Journal of veterinary pharmacology and therapeutics》2010,33(3):246-251
San Martin, B., Cornejo, J., Lapierre, L., Iragüen, D., Pérez, F., Hidalgo, H., Andre, F. Withdrawal time of four pharmaceutical formulations of enrofloxacin in poultry according to different maximum residues limits. J. vet. Pharmacol. Therap. 33 , 246–251. To ensure delivery of safe animal products to consumers, the withdrawal time (WDT) of drugs must be respected. Property differences among pharmaceutical formulations, for the same drugs, can lead to differences in the WDTs estimation. The WDTs of four commercial formulations of enrofloxacin (ENRO) in broiler chickens, considering MRLs established by different countries, were studied. Two hundred‐thirty‐four broiler chicks were allotted among four groups; the formulations were orally administered daily with 10 mg/kg bw. After treatment, six chickens of each group and two controls were slaughtered daily until day 9 post‐treatment. Samples of muscle and liver were collected, and analyzed using HPLC‐MS‐MS. The WDTs among formulations of ENRO showed differences of 24 and 48 h. Based on the European Community and Chile MRLs of 100 μg/kg (muscle) and 200 μg/kg (liver), the WDTs did not exceed 5 days. When Japan MRL was considered (10 μg/kg,), the WDTs increased up to 8 days. These results indicate that for WDTs determination, the differences among pharmaceutical formulations of a drug must be considered as well as the MRLs. 相似文献
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家蚕对8种除草剂农药的毒性反应 总被引：5，自引：0，他引：5
近年来农资部门和植保部门出售的除草剂品种繁多,新药不断出现,有许多除草剂在大田作物和桑园中使用,这些除草剂农药对家蚕的毒性如何?笔者等近年来做了大田常用除草剂农药对家蚕的毒性试验,本文报道8种除草剂对家蚕的触杀毒力、安全间隔期及中毒症状,以便为蚕农科学用药提供依据。 1 材料与方法 1.1 供试农药 市售41%农达水剂(美国孟山都公司),72%2,4－D丁酯水剂(河北万全农药厂),盖草能(中国农业生产资料集团公司分装),2%使它隆乳油(美国陶氏益农公司),20%克无踪水溶液(英国卜内门化学工业有限公司),50%高特克悬浮剂(德国艾格福公司),50%扑草劲可湿性粉剂(昆明农药厂)和10%新代力可湿性粉剂(浙江省乐清市乐吉化工厂)共8种。 1.2 供试蚕品种 春季781×782*734,秋季苏3*秋3×苏4*苏12,由省农科院蚕研所春用组提供。 1.3 试验地点及桑品种 在本所生理病理室和桑树研究室进行,6年生油桑品种,低干养成,7500株／ha 相似文献