The effects of feeding frequency on waiting time,milking frequency,cubicle and feeding fence utilization for cows in an automatic milking system

Abstract

In this trial, the effects of the forage feeding frequency on the waiting time prior to milking and the cowshed facility utilization by cows milked in an automatic milking unit (AMU) were studied. The feeding frequency was increased from two times per day to six times per day. It was found that the average waiting time per visit for cows using the AMU was reduced from 755 s to 351 s when the feeding frequency was increased. The daily number of visits (milking visit, failed milking visit and not qualified visit) to the AMU was not affected by the change in feeding frequency. It was also found that increasing the feeding frequency had a positive effect on utilization of the cowshed facilities, such as the occupation of the feeding fence, and on the cowshed facilities in the waiting area (cubicles) of the AMU.     

喷施赤霉素对甘蓝型油菜同源异型突变系AMS的影响

连续两年试验结果表明,对甘蓝型油菜同源异型无花瓣突变系(AMS)叶面喷施赤霉素(GA3)可明显改变AMS的开花性状,提高柱头外露率、花蕾质量、雌蕊长度和雌蕊质量;明显提高AMS植株生长速率,促进抽薹开花,使主花序的角果数明显增加;不同喷施浓度的试验表明在蕾薹期喷施1 700 mg/kg,2 200 mg/kg的处理效果较好;不同喷施浓度和时期的交互试验表明:喷施浓度和时期间存在交互作用, 相同浓度处理在蕾薹期的喷施效果优于显蕾期,在同一时期内喷施2 200 mg/kg处理的效果优于其他浓度处理,综合比较在蕾薹期喷施2 200 mg/kg处理的效果最佳.     

Management of grasslands in intensive dairy livestock farming

As livestock production has increasingly intensified resulting in larger and more specialised farm units, the role of grassland in the production system has been marginalised. The change in EU policy, however, may make grass as feed more competitive and thereby give grassland the opportunity for a comeback. The challenge for research and grassland farming practices is to reflect this new framework. This paper reviews different production and management systems - mainly focusing on grazing systems - within intensive dairy farming and aspects of feeding and quality of herbage in order to propose areas of special interest within the new framework. Farming systems based on a high proportion of roughage, such as in organic farming, and systems based on legumes need to be further developed. There is a need for an increased research effort in the area of interaction of supplementary feeds and seasonal effects and also in the area of the interaction of N and carbohydrate degradation in the rumen with milk response and N efficiency. Additionally, time-restricted systems based on a better understanding of animal behaviour should be emphasised in order to maintain a high grass intake and reduce the excretion of nitrogen on pasture. The interaction between grassland management and new technology such as automatic milking will be important in order to keep a high proportion of the dairy cows on pasture.     

吉林省农业支持与保护的实证分析

利用相关模型和指标对1996—2003年的吉林省农业支持与保护总体水平、边境保护情况、国内支持水平进行了定量分析。结果表明:从总体上看,吉林省农业仍处于负保护状态,并且保护水平与价格干预程度密切相关;从边境保护方面看,除玉米外,多数品种处于负保护状态,并且保护效果年际变化显著;从国内支持看,“黄箱”政策空间较大,而“绿箱”政策结构不尽合理,特别是对减少收入差距、促进社会公平的目标关注不够。     

逐级温度热解法在黄土古土壤样品~(14)C测年中的应用

利用已知可靠年代的黄土古土壤样品,采用逐级热解的方法,获取不同温度下的热解组分,运用加速器14C测年技术,测试各个组分的14C年龄,探讨获得可靠测年组分所需的逐步解热的实验条件。研究表明,逐级热解过程中,100℃～600℃温度段的热解挥发组分为年轻碳,而600℃～800℃温度段热解残余物(Py-R)则为老碳,600℃～800℃热解挥发组分(Py-V)是黄土-古土壤14C测年的可靠组分。     

天祝白牦牛乳中酶活性研究

本文利用分光光度法测定了不同放牧地和季节的天祝白牦牛乳的淀粉酶（AMS）活性，均不随地点的变化而呈现差异显著性（P〈0．05）。岱乾的牦牛乳中GSH—PX活性显著高于南泥沟牦牛乳（P〈0．05）。AKP活性在五月份显著低于一月和八月份。     

Palynology of late Quaternary coastal sediments, Perak, Malaysia

Twenty eight samples of peat, clay and silty clay from a tin mine exposure near Pantai Remis, Perak, Malaysia, were palynologically analyzed. Six pollen zones and eight subzones were delineated based on the dominant floral components. Accelerator mass spectrometry (AMS) radiocarbon and thermoluminescence datings on selected samples indicate late Pleistocene and older age. The occurrence ofPodocarpus imbricatus pollen suggests that the deposit is no older than late Pliocene. The fluctuation of sea level during the late Pleistocene is believed to be the main factor that influenced the development of vegetation at the Pantai Remis area. The presence of mangrove peat at depths between 13.0 m and 14.0 m, which overlies a freshwaterPandanus peat, indicates the position of a former shoreline at Pantai Remis when the area was inundated sometime during the last interglacial marine incursion. During this period of high sea level, thePandanus swamp was probably being gradually replaced by mangrove vegetation. The mangrove sequence is regarded as equivalent to the Kempadang formation. A slight drop in sea level sometime during the last glacial interstadial stage probably caused a small, open alluvial swamp to be developed over the mangrove forest. This freshwater deposit may be the equivalent of the Simpang formation.     

Chemical composition of young and old carbon pools throughout Cambisol and Luvisol profiles under forests

The long-term storage of soil organic matter (SOM) in forest soils is still poorly understood. In this study, particle size fractionation in combination with accelerator mass spectroscopy (AMS) and solid state ¹³C nuclear magnetic resonance (NMR) spectroscopy was applied to investigate organic carbon (OC) stabilisation in Cambisol and Luvisol profiles under spruce (Picea abies) and beech (Fagus sylvatica L.) forests. In most samples, OC was preferentially associated with <2 μm fractions. Throughout soil profiles the contribution of OC in the clay fraction to the total OC increased from 27%-53% in A horizons to 44-86% in E, B and EB horizons. The 200-2000 μm fractions from all sites and all depths showed a percentage of modern C (pmC)>100. They were enriched in ¹⁴C owing to high inputs of recent material from leaves and roots. Clearly less active material was associated with <2 and 2-20 μm fractions. This demonstrated that the particle size fractionation procedure applied to our study was capable to isolate a young OC fraction in all samples. The pmC values were strongly decreasing with depth but the decrease was much more pronounced in the fine fractions. The <2 and 2-20 μm fractions of B, E and EB horizons revealed radiocarbon ages between 512 and 4745 years before present which indicated that the SOM in those horizons was little affected by the recent vegetation. The major components of labile and stable SOM pools in topsoils and subsoils were always O/N-alkyl C (28-53%) and alkyl C (14-48%) compounds. NMR spectra of bulk soils and particle size fractions indicated that high alkyl C and O/N-alkyl C proportions throughout the soil profile are typical of Cambisols and Luvisols which were not subjected to regular burning. A relation between radiocarbon age and chemical composition throughout soil profiles was not observed. This suggests that the long-term stabilisation of SOM is mainly controlled by the existence of various mechanisms of protection offered by the soil matrix and soil minerals but not by the chemical structure of SOM itself.     

α-甲基苯乙烯二聚反应催化剂研究的进展

对α-甲基苯乙烯(AMS)二聚反应的催化剂研究进展进行了详细的阐述,结果表明:其催化剂的选择正向着使该二聚反应高转化率、高选择性、绿色化方向发展。