Pre-partum monensin supplementation improves body reserves at calving and milk yield in Holstein cows dried-off with low body condition score     

Melendez P  Goff JP  Risco CA  Archbald LF  Littell R  Donovan GA 《Research in veterinary science》2007,82(3):349-357

The objective of this study was to determine the effect of a monensin controlled-release capsule administered intraruminally at drying-off on body condition score (BCS) at calving, milk yield, fertility and concentration of energy-related blood metabolites in Holstein cows dried-off with low BCS (< or = 3.0, scale 1 to 5 with a 0.25 point of increment). Between July and August, 2001, 220 cows from parity 2 or more and dried-off 50-70 days before expected parturition, with a BCS < or = 3.0 were randomly assigned to either a treatment group (n=110; oral capsule of monensin releasing 335 mg/day for 95 days) or a control group (no capsule, n=110). At assignment, on day 21 before expected parturition, at calving, and at 7, 14, and 21 days in milk a blood sample was obtained from a random sub sample of 10 cows per group. Effects of monensin on serum NEFA, BHBA and glucose were measured. Milk yield, milk fat and protein content (%) at DHIA test days during the entire lactation, 305 ME milk production and reproductive responses were compared. Monensin significantly improved BCS at calving, increased milk yield at test days 4 and 8, decreased the percentage of milk protein, did not change the percentage of milk fat, and decreased NEFA and BHBA during the post-partum period.  相似文献   

除草剂莠去津降解菌SFAD3的分离鉴定及其土壤修复潜力     

何碧珀  赵辉  倪云霞  刘新涛  赵新贝  贾敏  刘红彦 《植物保护学报》2023,50(4):1096-1104

为获得能够修复除草剂莠去津污染土壤的高效降解菌,采用摇瓶富集法、平板分离法从莠去津过量使用的土壤中分离得到降解菌SFAD3,通过形态学、生理生化特征观察以及16S rDNA和ITS序列分析进行种类鉴定,测定获得菌株的最适降解条件,并通过土壤接种和盆栽试验验证菌株对莠去津污染土壤的修复作用。结果表明,菌株SFAD3最终被鉴定为门多萨假单胞菌Pseudomonas mendocina,该菌株培养30 d时对污染土壤中50 mg/kg莠去津的降解率可达72.6%;菌株SFAD3在MM液体培养基中最适降解条件为温度37℃、pH 7、莠去津初始浓度6.25 mg/L、接种量2%,对莠去津降的降解率为50.0%～72.2%;与仅有莠去津的处理相比,添加有SFAD3发酵液的处理20 d后芝麻的株高、根长、湿重和干重能够显著恢复,并且该菌对芝麻还具有一定的促生作用。表明降解菌SFAD3在修复莠去津污染土壤方面具有潜在的应用价值。  相似文献   

Asymmetric Exhaustive Service Polling System with Bernoulli Feedback     

SUN Rong-hen 《保鲜与加工》2001,(2):127-131

This paper studies asymmetric exhaustive service polling system with Bernoulli feedback,gives the distributions of queue lengths and sojoun times,and obtains some other results,in stationary condition.  相似文献   

ANALYSIS OF OPERATING CONDITIONS FOR DIAGONAL MINE FANS     

Ge Chunbo Xu Ruilong 《保鲜与加工》1990,(6):93-98

We shall discuss the real opererating conditions of the mine fans . in the mine diagonal ventilation system and establish a set of mathematics model for analysing the real engineering to provide judgement for technical manage ment of mine ventilation.  相似文献   

Balance Order and Interpolatory Property of M-band Multiwavelets     

MAO Yi-bo 《保鲜与加工》2005,(4):116-118

The p order balance and interpolatory property is introduced to M band multiwavelets. Balance conditions for M band multiwavelets are investigated in time domain and frequency domain respectively. The balanced order is equal to its approximation order for M band interpolatory multiwavelet.  相似文献   

Synthetic Assessment of Power Transformer Condition Based on Matter-element Theory     

XlONG Hao  SUN Cai-xin  DU Peng  DAI Yao  WANG Qian 《保鲜与加工》2006,(10):24-28

Condition assessment on power transformer is an important approach to improve reliability of transformer and provide proper decision-making for condition-based maintenance. For long, static assessment method used in the past has already not adapted to the development of modem electricity transmission and distribution technology. So based on the deficiency of fuzzy synthetic assessment method, matter-element synthetic assessment method is introduced. The method can evaluate transformer condition not only in quality but also in quantity. Because each index weight can be given fairly and fast through improved analytic hierarchy process, which need not carry on consistency chec accuracy of assessment can be improved. Examples analysis has proved that assessment method of power transformer condition based on matter-element theory is rational and effective.  相似文献   

The Unified Representation of Interface Conditionsof Electromagnetic Quantities Using Exterior Differential Forms     

Yun Zhengqing  Tan Bangding 《保鲜与加工》1994,(3):25-31

A continuity condition of p-forms across a p-dimensional submanifold isderived.The,various interface conditions of electromagnetic quantities are obtained through theapplication of the continuity condition to Minkowski manifold of space-time.  相似文献   

制动状态下的AMT换挡策略   总被引：3，自引：0，他引：3  

王玉海  宋健  李兴坤 《农业机械学报》2006,37(1):19-22,39

根据车辆动力学及发动机辅助制动特性研究了制动状态下AMT自动换挡策略。研究了高强度制动状况下在挡辅助制动对前、后轴利用附着系数的影响，获得了符合相关国家标准的换入空挡的临界车速。中强度持续制动可以识别为下长坡的运行工况，定义了辅助制动的等效制动强度，在分析试验数据的基础上给出了根据制动强度和车速2个参数的主动降挡辅助制动换挡规律。  相似文献   

利用振动特性诊断流程泵的运行工况   总被引：1，自引：0，他引：1  

倪永燕  袁寿其  潘中永  袁建平 《排灌机械》2007,25(2):49-52,60

用所建立的用于描述振动强度的范数说明了泵在偏离原设计工况运行时会导致泵轴向力和径向力的增大。将流程泵叶轮叶片和压水室的隔舌看作旋涡发生体，在不同运行工况下在叶片后缘以及隔舌两侧串联发生的卡门涡街的发射频率是不同的。采用加速度传感器采集的振动信号正反应了这种工况变动。通过对振动信号进行基于EMD的能量算子解调以及频谱分析，发现得到的最大幅值处的频率就是叶轮叶片的通过频率。试验表明，得到的次大幅值处的频率就是卡门涡街的发射频率，可根据该频率处幅值的相对大小来判断泵是否在合理的工况内运行。  相似文献   

合同解除制度的比较分析——以我国《合同法》与《联合国国际货物销售合同公约》为视角     

周敏  唐林峰 《湖南农机》2006,(5)

合同解除制度是合同制度的重要内容。我国《合同法》和《联合国国际货物销售合同公约》对合同解除制度都有比较详细的规定。本文试从合同解除的条件、程序及后果等方面对两者的规定进行比较分析。  相似文献