共查询到20条相似文献,搜索用时 187 毫秒
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虚拟仿真实验作为一种全新的实验课教学形式,解决了现实实验条件不具备或实际运行困难而无法开展实验的难题。结合疫情期间虚拟仿真实验在蜂学教学方面的应用情况,对虚拟仿真实验的优缺点进行了分析和总结,以期为虚拟仿真实验更好地服务蜂学教学提供借鉴。 相似文献
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袁伟康 戚南山 廖申权 Mudassar Mohiuddin 李跃龙 吕敏娜 吴彩艳 李娟 林栩慧 蔡海明 胡俊菁 于林增 肖文婉 张健騑 曹正 孙芸芸 孙铭飞 顾有方 《中国兽医学报》2021,(1):186-191
坏死性肠炎(necrotic enteritis,NE)是家禽中最重要的肠道疫病之一,呈世界性流行,严重危害养鸡业发展。人工复制鸡坏死性肠炎病例是研究该病发病机制及筛选有效药物的重要手段,然而在实际试验过程中,通常受实验动物、感染菌株、诱导病原等多方面因素影响而难以成功复制病例。鉴于此,现综述了影响鸡坏死性肠炎病例成功复制的关键因素,包括攻毒使用的实验动物、菌株毒素、菌株培养条件、诱导病因等,同时探讨了如何通过调整这些因素来改善人工复制鸡坏死性肠炎病例的严重程度,分析了鸡坏死性肠炎病例的病变评分系统,以期为鸡坏死性肠炎的实验室研究及综合防控提供理论基础。 相似文献
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进行动物科学试验时必须考虑到全部有较大效应的因素,只有那些远远小于处理效应的因素才可以通过"随机化"归入试验误差。对于"大效因素",无论是否随机化,都不能消除它们对试验结果的影响。现代家畜品种内变异常常很大,不同家系间遗传效应的差异常常超过试验因素的效应。所以进行动物试验时,包括动物饲养试验、消化代谢试验、饲养管理试验等,都需要考虑参试个体间的血缘关系。 相似文献
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Reproductive Performance of Native Pulawska and High Productivity Polish Landrace Sows in the Context of Stress During the Period of Early Pregnancy
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M Babicz M Szyndler‐Nędza E Skrzypczak A Kasprzyk 《Reproduction in domestic animals》2016,51(1):91-97
Experiments revealed that it is necessary to get rid of genotypes RYR1C/T and RYR1T/T because of problems with meat quality and reproduction of gilts and sows. This phenomenon, however, is of individual nature and is characterized by high variability. The aim of the study was to analyse the influence of stressogenic factors in native Pu?awska and high productivity Polish Landrace breed sows during the period of low pregnancy on reproductive performance and maternal behaviour. Sows in the 2nd reproduction cycle were assigned into groups of five animals as follows: control (C) of RYR1 C/C genotype and experimental (E) of RYR1 C/T genotype. In all, 30 Pu?awska breed sows and 30 PL breed sows were analysed. During the early stage of pregnancy (days 42–84), experimental groups were subjected to the action of stressogenic factors: elevated temperature, noisy and rough treatment of sows by service personnel and immobilization stress. The effect of stressogenic factors was referred to the reproductive performance of sows. Pu?awska and PL breed sows from the experimental groups were subjected to the evaluation of maternal traits on the basis of perinatal behaviour determined with the help of an ethogram. Analysis of the results of reproduction and the behaviour of the sows confirmed the higher resistance to stressogenic factors of the Pu?awska breed. The performed analysis of reproduction and behaviour confirmed that heterozygotic genotypes in the RYR1 locus exhibited less advantageous reproduction, which corroborates the hypothesis about a negative impact of the T allele on swine productivity. 相似文献
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正交试验法优选女贞子中特女贞苷的提取工艺 总被引:1,自引:1,他引:0
采用正交试验法优选女贞子中特女贞苷的最佳提取工艺条件,以加水量、提取时间与提取次数为考察因素,特女贞苷含量为评价指标对提取工艺进行考察。结果显示,特女贞苷的最佳提取工艺为加10倍药材质量的水,提取3次,每次2 h。该工艺为提高特女贞苷的提取率提供了实验基础,并为进一步的工业化生产提供科学的理论依据。 相似文献
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遥感与物联网耦合技术在土地生物资源动态管理中的应用 总被引:1,自引:0,他引:1
自然保护区是包含了土地自然资源、野生和畜牧生物以及人类社会的复杂系统,本研究以牲畜和草地资源关系为模式场景,通过哨兵2号(Sentinel-2)卫星影像提取的归一化植被指数(normalized difference vegetation index,NDVI)分析生物质覆盖率,通过穿戴式智能终端获得牦牛的位置和行为信息,并利用最小凸多边形法(minimum convex polygon,MCP)和整体动态加速度(overall dynamic body acceleration,ODBA)计算得到牲畜行为信息和活动量状态.结果表明:1)秋季NDVI呈显著减小趋势,冬季NDVI不再发生变化,其中2019年9月NDVI平均值达到最大值,为0.65,之后急剧减小;2)牧场围栏对于试验生物的活动能力和采食需求是有限边界,带犊牦牛和不带犊牦牛之间的家域面积无明显区别;3)在影响家域范围的因素中,人为因素基于其主观特性,影响力远大于其他因素,而物理隔离因素大于季节因素和其他环境因素;4)牦牛在2020年2月的家域面积最小,由于入冬后采食资源有限,牧场多辅以谷物饲喂,并利用附加围栏控制牦牛活动范围,避免其过多消耗能量.5)人为干预和采食资源减少的驱使下,试验生物趋向于保守的能量消耗策略,同时不带犊的生物由于负担较轻,活动量及能量消耗较小,在恶劣环境下具备更好的生存机会.本研究为实现数据采集、数据耦合和分析决策系统提供全新分析思路与方法,后续研究中将现有试验流程方法嵌入相对无限空间、低干扰试验环境,完成数据采集-耦合分析-反向决策干预验证的反馈闭环. 相似文献
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G S Elliott A H Rebar G P McCabe C Alzola 《American journal of veterinary research》1990,51(2):245-248
Important procedural factors in the under-agarose assay for porcine neutrophil migration were identified, and optimal conditions were established. Three factors were tested: the concentration of zymosan-activated serum inoculated into the outer well; the number of neutrophils inoculated into the center well; and the time of incubation of the agarose plates. All factors had a significant (P less than 0.0001, 0.0001, and 0.01, respectively) effect on the chemotactic index of porcine neutrophils. The optimal combination of these 3 factors was undiluted zymosan-activated serum as the chemoattractant, 8 X 10(5) neutrophils inoculated into the center well, and 5 hours of incubation. The assay was validated, using standard conditions, and the data were used to predict the number of pigs and/or repetitive assays needed to identify differences among experimental groups. 相似文献
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对家禽饲料代谢能值评定方法中若干误区的探讨 总被引:6,自引:0,他引:6
迄今国际上对禽类饲料代谢能值的表述有诸多方式。在其立论依据、试验设计及测试手段等方法学方面存在着许多悬而未决的问题。本文通过饲料间组合效应,试验设计中的养分有效性分配原则,对经典的套算法在推理中的随意性以及在建立数学模型时必要的校正因子的扬弃等问题进行了探讨。限于篇幅,对家禽饲料代谢能评定方法的技术路线问题拟做另文探讨。 相似文献
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通过正交试验设计和感官评分,选用不同的发酵剂添加量(A)、发酵温度(B)和时间(C)、液体麦精量(D),采用四因素三水平进行正交试验,以产品的感官评分为评价指标,筛选出因素水平最佳组合。结果显示:因素影响排序为:A>D>C≈B;格瓦斯酸奶的最佳工艺参数为A2B1C3D3,即发酵剂添加量0.004%,发酵温度28℃,发酵时间14 h,液体麦精添加量3%。经生产验证,上述较佳因素水平组合能够获得细腻柔软的凝乳,并带有独特开菲尔风味及温和烤面包风味的饮用型格瓦斯酸奶。 相似文献