A moving block evaluation technique for improving the efficiency of pedigree selection     

A. C. Fasoulas 《Euphytica》1987,36(2):473-478

Summary Pedigree seletion on the basis of moving block adjustment encompasses a two-phase cycle per year, i.e. family selection at a number of sites representing production environments for which adaptation is sought, and individual plant selection wihtin selected families at an extra site. Family selection within sites is based on moving blocks consisting of sets of contiguous plots, the number of which varies according to the chosen selection pressure. Families are unreplicated within each site and family selection across sites is based upon the family selection index F, i.e. the number of sites at which a particular family has been selected. The use of moving blocks for control of variation in growing conditions wihtin sites, and of the index F for exploiting genotype-site interaction early in the program, is expected to increase efficiency and to save time required to release a cultivar, as regional tests become unnecessary. In addition, the procedure allows screening an unrestricted number of families at any number of sites, in both self-and cross-fertilizing crops.  相似文献   

Low-rent House-Real Choice for Help to the Urban Vulnerable Groups in House Needs     

QIU Dong-yang  WANG Mu 《保鲜与加工》2003,(6):124-129

This paper analyzes the urban vulnerable groups in house needs, as well as housing security policy; the conclusion is to carry out low-rent house system. Furthermore, the shortcoming lies in system, fund, object, quantity and information nowadays is pointed out. The countermeasures perfecting the low rent house system are presented. There is a strategy named "helps to others and oneself" to realize a policy that the powerful and the vulnerable groups must have symbiotic development, to form steady normative source of insurance fund, to play an effective role in low rent house stock, to establish managerial mechanism which all the departments are on duty, to build system from low rent house application to its supervision, to take the manner of rent allowance, to perfect correlative policy of low rent house and house security.  相似文献   

Shifting focus from the population to the individual as a way forward in understanding,predicting and managing the complexities of evolution of resistance to pesticides     

Michael Renton 《Pest management science》2013,69(2):171-175

The evolution of resistance to pesticides is often conceptualised and modelled at a population level, but population‐based approaches ignore important aspects of variability between individuals within populations that may be essential drivers of resistance. Here it is argued that individual‐based modelling has the potential to generate new insights and perspectives, thus deepening our understanding of the complexities of the evolutionary dynamics of resistance to pesticides. Copyright © 2012 Society of Chemical Industry  相似文献   

基于RFID技术的养猪场个体识别系统设计     

程佳威  李亚敏  王艳红 《湖北农业科学》2013,52(7)

为顺应当前畜牧业的发展趋势,满足市场对生猪生产质与量的需求,设计了基于RFID技术的生猪个体快速识别系统.系统以8位CMOS单片机AT89C2051、读写芯片MFRC522、标签芯片I·CODE SLILabel IC SL2 ICS20(简称I·CODE2)作为核心硬件,实现了对猪的个体识别和信息追踪.该系统简单,便于实现,有较高的可靠性,可应用于大规模养猪场,有助于养殖的自动控制.  相似文献   

河北省不同建筑类型的肉牛场舍内外有害气体的比较研究     

高玉红  曹玉凤  于海川  赵凤存  李雪梅  李建国 《河北农业大学学报》2013,(1):100-104

通过检测河北省不同地区6个有代表性建筑类型的肉牛场舍内外空气中的有害气体,对夏季和冬季肉牛舍的空气环境质量进行分析。不同季节各牛场的舍内、舍间和场中氨气(NH3)含量差异明显,夏季敞棚舍内NH3含量与舍间没有表现出显著差异,但有窗舍和半开敞舍内NH3含量远高于舍间和场中。冬季除了敞棚舍,其他牛舍内NH3含量远高于夏季,尤其3种密闭牛舍内NH3含量达到7.8～10.8mg/m3,而夏季只有0.92～0.95mg/m3,且检测高度1.2m的NH3含量显著高于0.6m;夏季各牛舍内外CO2含量均没有表现出显著差异,而冬季均超标(敞棚舍除外),尤其密闭牛舍CO2含量平均高达3 811mg/m3。  相似文献   

Well-being in Pregnant Sows: Confinement versus Group Housing with Electronic Sow Feeding     

Karin H. Jensen  Bjarne K. Pedersen  Lene J. Pedersen  Erik Jørgensen 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(4):266-275

Abstract

Indicators of stress, behaviour in the pen, and lesions of the integument were used as indicators of sow well-being in a comparison of group housing with electronic sow feeding [GH] and confinement in gestation crates [C] in experiment 1, which included 2 × 4 groups of 20–25 sows. Effects of earlier experience with a gestation system on the indicators of stress was investigated in experiment 2, which included 2 × 3 groups of 20–25 sows. Reaction in a novelty test and reactivity in plasma Cortisol to the procedure of blood sampling were used as indicators of stress. Behaviour in the pen as well as lesions of the integument revealed that both gestation systems were suboptimal in some manner. However, following acclimatization for 1–2 weeks, young GH sows experienced less stress than young C sows as measured by reduced fear in the novelty test. In experiment 2 this interpretation was further supported by lower reactivity in plasma Cortisol. It was concluded that sow well-being was higher for the majority of the gestation period in young group-housed animals. Thus, in spite of the inadequate feeding method, well-being of sows may be improved in group housing systems with electronic sow feeding if the system is well functioning with low levels of aggression and vulva bites. One of the major determinants of vulva biting is suggested to be the mechanism of gate control.  相似文献   

Housing of Norwegian goat herds and associations with milk yield and milk quality     

E. Simensen  F. Hardeng  T. Lunder 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(3):187-193

Abstract

Data from a questionnaire regarding housing factors were merged with data from the milk recording databases (herd mean annual milk yield per goat, somatic cell count (SCC) and bulk milk bacterial count), and the material included 235 herds. Associations with housing factors were tested at herd level and at individual goat level. Housing in insulated buildings with no access to outdoor areas during the winter season, expanded metal grating and no use of bedding predominated. None of the housing factors evaluated were significantly associated with milk yield. In herds using water nipples, SCC was lower compared to herds using water bowls. SCC was also lower in herds with milking facilities in separate milking stalls as compared with combined feeding milking stalls in common pens. No significant associations were found between housing factors and bacterial counts, but the counts were lower in herds with high average milk yields per goat.  相似文献   

汽车离合器壳体泄漏测试站的设计     

王凯斌  吴涛  曾照斌  张磊  郑舟 《农业机械化与电气化》2013,(10):37-39

根据汽车离合器壳体的结构特点,采用机械与电气自动化控制相结合的方法,利用气体泄漏测试仪对离合器壳体的内在质量（气孔、砂眼、断芯等）进行检测。介绍气体泄漏测试站的工作原理、所需设备及检测方法,为汽车离合器壳体的质量检测提供依据。  相似文献   

水冷式猪床冬季保温措施对妊娠母猪小群饲养的影响   总被引：2，自引：2，他引：0  

李伟  林保忠  刘作华  王朝元  李保明 《农业工程学报》2012,28(22):222-226

为探讨在冬季低温条件下水冷式猪床保温措施对妊娠母猪小群饲养的影响,试验选用16头配种4周左右的母猪,随机分为对照组和试验组,每组各2圈栏,每圈栏4头。在试验组猪床单元两端设有门帘来提高猪床内环境温度,测试各组环境温度及观察母猪行为。结果表明:单个猪床单元内1头猪躺卧时,试验组单元内温度比对照组和舍内温度平均分别高3.2和6.9℃,当试验组和对照组舍内温度分别高于11和12℃,均未出现2头猪挤在1个单元内躺卧。试验组与对照组相比,母猪每天平均躺卧时间(18.6和17.8h)和饮水次数(18.5和23.3)差异显著(P<0.05),咬链次数(14.0和19.0)差异极显著(P<0.01)。对照组在猪床单元内排便和排尿分别占总次数的1.8%和12.1%,而试验组分别为0和3.2%。研究结果表明,猪床门帘可提高母猪躺卧区的局部温度和减少母猪的刻板行为。  相似文献   

华北地区商品蛋鸡舍冬季环境管理   总被引：1，自引：1，他引：1  

施正香  温树香 《中国农业大学学报》1997,2(6):71-75

对北京地区典型商品蛋鸡舍的冬季环境进行了实验调研和测试分析。结果表明；冬季鸡舍在正常通风换气一为１．３－１．５ｍ＾３．ｈ＾－１，只＾－１时，舍内外温差可维持在１９℃左右，相对湿度在６５％－８５％之间，ω（ＣＯ２）在２１×１０＾－４左右，ω（ＨＮ３）〈２０×１０＾－６。在这种环境条件下，蛋鸡冬季产蛋率仍比正常生产性能低３％－５％。  相似文献