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41.
Test data generated by ~60 accredited member laboratories of the American Association of Veterinary Laboratory Diagnosticians (AAVLD) is of exceptional quality. These data are captured by 1 of 13 laboratory information management systems (LIMSs) developed specifically for veterinary diagnostic laboratories (VDLs). Beginning ~2000, the National Animal Health Laboratory Network (NAHLN) developed an electronic messaging system for LIMS to automatically send standardized data streams for 14 select agents to a national repository. This messaging enables the U.S. Department of Agriculture to track and respond to high-consequence animal disease outbreaks such as highly pathogenic avian influenza. Because of the lack of standardized data collection in the LIMSs used at VDLs, there is, to date, no means of summarizing VDL large data streams for multi-state and national animal health studies or for providing near-real-time tracking for hundreds of other important animal diseases in the United States that are detected routinely by VDLs. Further, VDLs are the only state and federal resources that can provide early detection and identification of endemic and emerging zoonotic diseases. Zoonotic diseases are estimated to be responsible for 2.5 billion cases of human illness and 2.7 million deaths worldwide every year. The economic and health impact of the SARS-CoV-2 pandemic is self-evident. We review here the history and progress of data management in VDLs and discuss ways of seizing unexplored opportunities to advance data leveraging to better serve animal health, public health, and One Health.  相似文献   
42.
于2006年对10个大黍(Panicum maximum)品种的生产性能和品质特性进行区域试验研究,旨在筛选出适宜于热带、亚热带地区种植的高产、优质牧草,以期为热区畜牧业的持续发展提供依据。结果表明,1)所引种牧草的存活率、越冬率都在94%以上,说明所引种牧草的适应性强;2)除TD 58坚尼草、坦桑尼亚大黍和热研8号坚尼草感染了叶锈病以外,其他牧草的抗病虫害能力均较强;3)种植第1年,坦桑尼亚大黍干物质产量最高,为45.33 t·hm-2,与MG 7 Aries大黍、MG 6 Atlas大黍、蒙巴萨大黍、热研8号坚尼草、热研9号坚尼草和TD 58坚尼草之间差异不显著;4)选择干草产量、粗蛋白、适口性和抗逆性作为综合评价供试品种优劣的指标,用灰色关联法评价牧草,结果表明,蒙巴萨大黍、坦桑尼亚大黍、热研8号坚尼草、MG 6 Atlas大黍和TD 58坚尼草居前5位,它们属高产、质优、适口性好、抗性强的高产优质牧草品种。  相似文献   
43.
ABSTRACT

1. Enzymes have been used commercially for nearly 40 years and save significant costs through sparing of expensive nutrients but the mechanism by which this is achieved is still debated.

2. The research focused on non-starch polysaccharidase (NSPase) enzymes is used as an example of where greater progress could have been made if the details of the work had been described more fully and the analysis of the data generated had been broader in scope and more critical.

3. Lack of standardisation of the details presented in the materials and methods has been identified as a significant barrier to meaningful retrospective analysis and thus limits advances in the understanding of the mode of action of these enzymes.

4. The identity of the enzyme employed and its activity is often lacking, and more importantly the purity is rarely disclosed. Contaminant activities which are neither listed nor assayed could play a significant role in the responses observed.

5. The dose optimum of most enzymes is often considerably higher than that employed in most studies. Thus studies claiming synergy between two ‘activities’ should ensure that the response is not related to each enzyme simply augmenting the dose of just one activity in the finished feed. This is a common problem, and coupled with the lack of factorial experiments to justify the presence of each enzyme in a multi-enzyme product, it is not surprising that there is still debate as to whether single or multi-enzymes are best suited poultry rations.

6. The three proposed mechanisms for NSPases (viscosity, cell wall and prebiotic) are discussed, and along with their strengths and weaknesses it is suggested that a re-evaluation of each is needed. Viscosity may have to be re-evaluated as being a function not only of the cereal being fed, but of the age of the animal as well. The cell wall theory as described is poorly modelled in vitro and hence the validity of these data is questioned. The prebiotic theory may need significant modification as it appears that the quantities of oligomers produced are insufficient to generate the additional volatile fatty acids (VFA)’s reported. It is likely that all three mechanisms play a role in the responses observed, but the prebiotic mechanism probably plays by far the most important part in low viscosity diets.

7. Future research would be improved if it considered all potential mechanisms when designing a trial. Significant failings are apparent as a result of adherence to tenets in explanation of the results. Most importantly, it should be emphasised that a hypothesis is there to be tested, not defended.  相似文献   
44.
20世纪80年代出现的寻根文学是新时期文学发展的一次重要探索。它对于新时期文学的意义是巨大而深远的。它提供了政治话语写作以外的另一种写作范式,指明了小说可以朝着无限广阔的文化领域进军,召唤着作家大胆借鉴新的创作资源。当它为后人提供可资借鉴的学术资源时,也存在着许多不足。文中主要从“寻根文学”的渊源、背景、理论、作家作品及所受到的外来影响等多方面试图对寻根文学做一次较为全面的梳理和把握。  相似文献   
45.
综合英语课是研究生英语学习的基础课。笔者从教学实践论证了把合作学习理论引入综合英语教学的必要性和可行性。研究结果表明,通过合作学习有利于转变研究生英语学习理念,将语言学习与发展语言能力有机结合起来,有助于研究生综合语言能力的提高,为更高层次的英语选修课学习打好基础。  相似文献   
46.
郑江涛  陈维 《猪业科学》2021,38(8):39-41
应激是动物机体在多种环境、生理和心理等因素的刺激下,出现的生理与心理等全身性的非特异性的适应性反应.随着我国生猪养殖业规模化和集约化程度的提高,养猪生产者都追求以有限的养殖空间来生产更多的猪只,这导致了养殖密度的增加、猪群应激发生的概率不断上升.应激导致的危害日益突出,成为了阻碍猪只健康生长的重要的因素之一.本文回顾了...  相似文献   
47.
为了探索特异性免疫学诊断方法对鸡骨型白血病(OP)的检测效果。用双盲法分批采样同时进行羽髓琼脂扩散试验和胫骨X线摄片检查对比,共检834只鸡(433羽属天然自发OP鸡群,401羽属人工诱发实验鸡群)。结果羽髓琼扩试验的OP阳性检出率为3.48%(29/834:)。阳性病理符合率为75.86%(22/29)。阳性误诊(假阳性)率24.13%(7/29),阴性误诊(假阴性)率36.15%(291/805)。而X线摄片检查的OP阳性检出率为38.37%(320/834)。X线阳性完全可获病理组织学证实,不存在假阳性或假阴性。把禽白血病羽髓琼扩试验试用于检测鸡骨型白血病尚属初次报道,其阳性检出率低而误诊率高,尚不宜作OP检测手段。放射摄片诊断的阳性检出率高而误诊率低,可快速诊断,故适用于OP检疫。  相似文献   
48.
49.
上市公司高层变动受多种因素的影响,经营业绩是其中一个重要因素,能有效反映公司经营绩效的财务信息,对高层变动的影响也是不容忽视的.通过对深市样本公司的高层变动与会计信息的实证分析,进一步证明了不同会计信息对高层变动的影响程度及二者的关系,从而为投资者和管理者及其他财务数据使用者提供有效的参考依据.  相似文献   
50.
There is an increasing interest in using whole‐genome sequence data in genomic selection breeding programmes. Prediction of breeding values is expected to be more accurate when whole‐genome sequence is used, because the causal mutations are assumed to be in the data. We performed genomic prediction for the number of eggs in white layers using imputed whole‐genome resequence data including ~4.6 million SNPs. The prediction accuracies based on sequence data were compared with the accuracies from the 60 K SNP panel. Predictions were based on genomic best linear unbiased prediction (GBLUP) as well as a Bayesian variable selection model (BayesC). Moreover, the prediction accuracy from using different types of variants (synonymous, non‐synonymous and non‐coding SNPs) was evaluated. Genomic prediction using the 60 K SNP panel resulted in a prediction accuracy of 0.74 when GBLUP was applied. With sequence data, there was a small increase (~1%) in prediction accuracy over the 60 K genotypes. With both 60 K SNP panel and sequence data, GBLUP slightly outperformed BayesC in predicting the breeding values. Selection of SNPs more likely to affect the phenotype (i.e. non‐synonymous SNPs) did not improve the accuracy of genomic prediction. The fact that sequence data were based on imputation from a small number of sequenced animals may have limited the potential to improve the prediction accuracy. A small reference population (n = 1004) and possible exclusion of many causal SNPs during quality control can be other possible reasons for limited benefit of sequence data. We expect, however, that the limited improvement is because the 60 K SNP panel was already sufficiently dense to accurately determine the relationships between animals in our data.  相似文献   
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