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61.
M. De Vos L. Che V. Huygelen S. Willemen J. Michiels S. Van Cruchten C. Van Ginneken 《Journal of animal physiology and animal nutrition》2014,98(4):609-619
Selection for hyperprolific sows, as a means of increasing litter size and profit, has resulted in an increased number of low‐birthweight (LBW) piglets. These LBW piglets might suffer from increased morbidity and mortality during the early neonatal period. In addition, they show reduced growth performance, meat and carcass quality, which leads to an important economic loss for the farmer in the post‐natal period. Therefore, nutritional interventions can be undertaken to prevent and rear LBW piglets. In the first part of this review, the preventive strategies at the sow level will be discussed. Approaches in preventing LBW piglets are to optimize the intrauterine environment via supplementing the sow during gestation. In the second part of this review, the interventions at the piglet level will be described. To increase the survival and growth rates of LBW piglets, one must focus on ensuring adequate colostrum and milk intake. Interventions include supplementing piglets, split nursing, split weaning and cross‐fostering. Additional interventions increasing the probability of optimal post‐natal food intake will be discussed. 相似文献
62.
草地土壤肥力及其营养管理的必要性 总被引:3,自引:0,他引:3
介绍了草地土壤肥力的来源,土壤基本养分对草地生产的作用,草地植物与动物对养分的需求量及缺乏症状,说明了加强草地营养管理以及维持草地生态系统营养平衡的重要性,指出增强对土壤肥力和营养管理是提高草地生产能力、保证草地生态系统平衡、保障草地可持续利用的关键技术措施。 相似文献
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66.
文章结合中国网通近两年来内部控制项目实施的实际情况和圆满通过外部审计师审计的经验,对目前通信网络设备维护工作中存在的问题和相应带来的风险进行剖析 相似文献
67.
农业现代化是衡量国家现代化的一个重要指标。在国家强农惠农政策的引导下,东海县应逐步改变传统的农业生产模式,实现农业生产集中化、机械化、现代化。同时可尝试多行业、各技术融合,促进农机化和农机管理工作更上一层楼。 相似文献
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69.
Eugenia Fezza Joe M. Roberts Toby J. A. Bruce Lael E. Walsh Michael T. Gaffney Tom W. Pope 《Pest management science》2023,79(11):4635-4643
BACKGROUND
Monitoring is an integral component of integrated pest management (IPM) programmes used to inform crop management decisions. Vine weevil, Otiorhynchus sulcatus F. (Coleoptera: Curculionidae), continues to cause economically significant losses in horticultural crops due to an inability to reliably detect the presence of this species before crop damage occurs. To improve vine weevil monitoring we investigated the behavioural responses of adult vine weevils to visual (monitoring tool shade/colour, height and diameter as well as the effect of monitoring tool and plant density) and olfactory (host plant and conspecifics) cues under glasshouse conditions.RESULTS
Monitoring tool shade, height and diameter all influenced monitoring tool efficacy, with individuals exhibiting a preference for black, tall and wide monitoring tools. The total number of individuals recorded in monitoring tools increased with monitoring tool density. By contrast, plant density did not influence the number of individuals recorded in monitoring tools. Yew-baited monitoring tools retained a larger number of individuals compared to unbaited ones. Similarly, more vine weevils were recorded in monitoring tools baited with yew and conspecifics than in unbaited monitoring tools or those baited with only yew. Baiting monitoring tools with conspecifics alone did not enhance the number of vine weevils recorded in monitoring tools.CONCLUSIONS
Our study confirms that visual and olfactory cues influence vine weevil behaviour. This provides information on key factors that influence vine weevil monitoring tool efficacy and can be used to inform the development of a new monitoring tool for this pest. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献70.