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In a study carried out during 2002 and 2004 in Diyarbakıir and Mardin provinces, southeast Turkey, specimens were collected
twice a month from cultivated and non-cultivated plants. Sixteen leafminer (Diptera: Agromyzidae) species were identified.
Among them,Agromyza abiens Zetterstedt, 1848;Napomyza elegans (Meigen, 1830);Phytoliriomyza dorsata (Siebke, 1864); andPhytomyza aquilonia Frey, 1964 are new records for the Turkish leafminer
http://www.phytoparasitica.org posting July 24, 2005. 相似文献
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本文报道了我国的3种枝角类雄体新记录,描述了形态特征。还对另2种枝角类雄体作了新的补充描述。 相似文献
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The Coccoidea of cultivated and non-cultivated areas of Ankara Province, in central Anatolia, Turkey, were surveyed between
1999 and 2001. Eleven species of Eriococcidae were collected, of which nine are new records for Turkey:Acanthococcus greeni Newstead,A. micracanthus Danzig,A. munroi Boratynski,A. roboris (Goux),A. zernae Tereznikova,Rhizococcus cingulatus (Kiritchenko),R. cynodontis (Kiritchenko),R. herbaceus Danzig andR. pseudinsignis (Green).
http://www.phytoparasitica.org posting Sept. 30, 2003. 相似文献
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Retrospective analysis of trends and production factors associated with sow mortality on swine-breeding farms in USA 总被引:2,自引:0,他引:2
Koketsu Y 《Preventive veterinary medicine》2000,46(4):249-256
Of the 825 pig farms in USA that mailed in their electronic file containing production records, 604 farms were used to observe breeding-female mortality risk and related factors (herd size, lactation length, parity and season). Multiple regression was used to determine factors associated with annual mortality risk. Analyses of variance were used for comparisons of mortality risks among parity and season groups. Average annual mortality risks during the 1997 period was 5.68%. Average breeding-female inventories and average lactation length on USA farms were 733 and 18.3 days, respectively. Higher annual breeding-female mortality risk was associated with larger herd size, greater parity at farrowing and shorter lactation length (P<0.02). For example, as herd size increases by 500 females, mortality risk increases by 0.44%. Older parity was associated with higher mortality risks. Summer season was also associated with higher mortality risk. Using five-years’ records on 270 farms, annual mortality risk in 1997 was higher than those of 1993 and 1994, while average breeding-female inventory increased and lactation length decreased. It is recommended that producers, especially in large herds, pay more attention to breeding females. 相似文献
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M.J. Surez S. Munilla R.J.C. Cantet 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(1):21-29
Animals born by embryo transfer (ET) are usually not included in the genetic evaluation of beef cattle for preweaning growth if the recipient dam is unknown. This is primarily to avoid potential bias in the estimation of the unknown age of dam. We present a method that allows including records of calves with unknown age of dam. Assumptions are as follows: (i) foster cows belong to the same breed being evaluated, (ii) there is no correlation between the breeding value (BV) of the calf and the maternal BV of the recipient cow, and (iii) cows of all ages are used as recipients. We examine the issue of bias for the fixed level of unknown age of dam (AOD) and propose an estimator of the effect based on classical measurement error theory (MEM) and a Bayesian approach. Using stochastic simulation under random mating or selection, the MEM estimating equations were compared with BLUP in two situations as follows: (i) full information (FI); (ii) missing AOD information on some dams. Predictions of breeding value (PBV) from the FI situation had the smallest empirical average bias followed by PBV obtained without taking measurement error into account. In turn, MEM displayed the highest bias, although the differences were small. On the other hand, MEM showed the smallest MSEP, for either random mating or selection, followed by FI, whereas ignoring measurement error produced the largest MSEP. As a consequence from the smallest MSEP with a relatively small bias, empirical accuracies of PBV were larger for MEM than those for full information, which in turn showed larger accuracies than the situation ignoring measurement error. It is concluded that MEM equations are a useful alternative for analysing weaning weight data when recipient cows are unknown, as it mitigates the effects of bias in AOD by decreasing MSEP. 相似文献
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由“植物诊所”形成的电子病历为作物病害处方推荐提供了新的思路。如何高效地挖掘电子病历数据并辅助作物病害处方推荐,目前还是亟待解决的研究热点问题。在总结和整理现有国内外研究文献的基础上,对基于显微图像的作物病害病菌孢子识别、基于光谱的作物病害诊断、基于电子病历的作物病害处方推荐等作物病害诊断与处方推荐关键技术进行了系统分析与讨论。综述结果表明,围绕作物病害病菌侵染过程,以智能化处方推荐需求为导向,开展基于电子病历数据挖掘的作物病害处方推荐研究,将成为一个研究重点。针对作物病害处方推荐过程中,存在由于作物病害致病机理复杂、作物品种及病害种类多、病害病症动态变化且特征多等特点和难点,研究基于电子病历数据挖掘的作物病害致病机理解析、诊断推理、智能化处方推荐及其应用策略,将是研究的重大方向;探索基于知识图谱分析、大数据挖掘和机器学习算法推理等关键技术的作物病害电子病历数据挖掘分析研究,从区域宏观视角可视化解析作物病害致病机理及其与特征间的关联关系,面向实际应用场景实现基于诊断推理的单一作物病害处方推荐、基于语义匹配的多种作物多种病害处方推荐,具有更大的实际意义。 相似文献
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通过对围网渔船起网过程中所受外力的实测和分析,表明在绞收括纲阶段临近结束时,即底环集中串挂在船舷括纲吊柱处时的外力,最大可达7,140公斤。起网时外力对船作用最终表现为外力矩,其数值与网具的纲索或网衣相对于船的出水点位置以及各种捕捞、起吊设备的安装位置有关,也即与力的作用线方向和作用点有关。作者认为在围网渔船稳性核核中,仅校核起吊底环和绞收网衣时的倾侧力矩是不够的,应选取整个起网过程中最大起网力矩(绞纲阶段末尾的倾侧力矩)用于渔船稳性校核和摇摆计算。 相似文献