Relationships between dairy cow mastitis and fertility management and farm performance

A field study was carried out on 38 dairy farms in the Netherlands to determine the relationship between mastitis and fertility management with 305-day milk production and gross margin. Questionnaires were used to get insight into the farmers' management. Out of 150 variables related to mastitis and fertility management, and technical and economic results, 44 variables were selected based on correlation of ≥0.25 or ≤−0.25 with milk production and/or gross margin. These variables were used in two separate partial least-squares (PLS) analyses. PLS has the advantage that it can handle a large number of variables in relation to the number of cases. The PLS-model of 305-day milk production had R² = 0.54 and showed a positive relation between 305-day milk production and awareness of the farmer regarding bulk somatic-cell count (BSCC), the goal level of the farmer for BSCC, and hygiene of the milking parlour. Fertility was negatively related to 305-day milk production, in spite of a relatively good fertility management on high-producing farms. R² = 0.46 for gross margin. The aspiration level of fertility did not seem to affect gross margin, but awareness of BSCC and calving interval (CI) had positive effects. Such awareness seemed a general parameter for good economic results, because it was correlated with different aspects of gross margin.     

尤溪县林缘山脚田边生物防火林带建设现状与对策

阐述尤溪县林缘山脚田边生物防火林带建设基本情况,以及设置山脚田边生物防火林带的重要性、山脚田边生物防火林带在防火中的作用,提出营造山脚田边生物防火林带的对策措施,为今后进一步推动山脚田边生物防火林带建设提供参考。     

祁连山冷龙岭北麓冰川缘地文冠果引种栽培

在祁连山冷龙岭北麓冰川缘地——中牧甘肃山丹马场海拔高度不同的5个试验地(海拔分别为2 560、2 900、2 800、2 500、2 480 m,分别记作spot i,i=0,…,4))引种文冠果.结果表明:1～3年生文冠果播种苗平均苗高由高到低顺序:spot 0＞spot 3＞spot 4＞spot 2＞spot 1,其中spot 1播种苗、插根苗和移植苗连年生长量为零,spot 2苗木连年生长量部分为零.5个试验点的播种苗、插根苗、移植苗地下部分越冬成活率均达到100％.苗木平均枯梢率由大到小依次为spot 1＞spot 2＞spot 4＞spot 0＞spot 3.其中移植苗的枯梢较播种苗轻.在试验地发现文冠果苗木有黄化病和立枯病.spot 3、spot 0、spot 4所在地较适合文冠果的栽培,4年生播种苗在样地3只有1株结果,5年生时无开花及结果的情况.     

植物叶缘锯齿发育调控的研究进展

叶片是植物重要的营养器官,叶片的形成模式和发育涉及激素信号和转录因子间复杂遗传网络的调控。叶缘锯齿的产生是植物对不同环境长期适应的结果,对植物应对高温、干旱等逆境胁迫及响应光周期都有十分重要的作用。为了更清晰地认识植物叶缘锯齿的发育过程,本研究对植物叶缘锯齿形成过程中重要的调控因子及其调控机制进行了分类和总结。叶缘锯齿的发育受生长素、细胞分裂素、赤霉素等植物激素,NAM/CUC、TCP、SPL等转录因子,KNOX基因家族及其他调节因子的调控,并在单叶和复叶植物中表现出明显不同的调控模式。植物叶缘锯齿发育仍有很多未知的调控因子,因此,未来一个重要的研究方向就是要继续挖掘和鉴定更多参与植物叶缘锯齿发育的调控因子,并进一步解析其作用的分子机制,从而为今后通过调控叶形为其他作物性状改良提供理论依据。     

星豹蛛在丘陵山地的活动规律初步研究

用陷阱法和目测法对丘陵区各个栖境的星豹蛛Pardosa astrigera C．L．Koch(Ly- cosidae：Pardosa C．L．Koch)做了初步调查研究,结果表明,星豹蛛5月下旬前主要在边界、沟渠、碎石路和斜坡处活动,而苹果园中相对较少。当边界、沟渠和碎石路植被长高后,星豹蛛迁移至周围的苹果园中。6月下旬7月下旬苹果园中星豹蛛受高温影响数量下降明显；8月下9月其数量又有较大回升。研究还发现,10月中下旬星豹蛛在背阴地带出现的频率明显少于光照较好的地带；同期星豹蛛可能还有趋向干枯杂草的习性。     

Long-term postsurgical outcomes of mast cell tumors resected with a margin proportional to the tumor diameter in 23 dogs

We evaluated the postsurgical outcomes of cutaneous or subcutaneous mast cell tumors (MCTs, n=25) in 23 dogs, resected with lateral surgical margins proportional to the widest tumor diameter, including at least one facial plane. The tumor diameter range was 0.3–2.6 cm (median: 0.9 cm), and all were histologically diagnosed as Kiupel’s low-grade MCT. Resection was histologically complete in 20, close (deep margin) in three, and incomplete (deep margin) in two. No dogs developed local recurrence at the site of initial surgery during follow-up of 161–2,219 days (median: 976 days). These results suggest that resection of low-grade, relatively small MCTs with surgical margins proportional to the tumor diameter is a practical procedure with high success rates.     

淮南麻黄鸡舍饲的肉用性能研究

通过对淮南麻黄鸡进行舍饲,探讨其早期生长发育规律及屠体品质．结果表明：淮南麻黄鸡５周龄日增重最高,达２２．８６ｇ;而相对生长速度高峰在１一２周龄,其次在５周龄;１１周龄淮南麻黄鸡均重为７６９．２５士１１６．９１ｓ（公鸡８４７．３８士１０２．２５ｇ,母鸡６９１．１３士６８．９３ｇ,料肉比３．１：１;屠体品质公鸡优于母鸡;饲养淮南麻黄鸡所取得的利润率高于肉仔鸡。     

A case study of cash cropping in Nepal: Poverty alleviation or inequity?

Agricultural commercialization as a mechanism to alleviate rural poverty raises concerns about small land-holders, non-adopters, and inequity in the distribution of benefits within transforming economies. Farm gross margins were calculated to assess the economic status and impact of cash cropping on the economic well-being of agrarian households in the Mid-hills of Nepal. On an individual crop basis, tomatoes and potatoes were the most profitable. On a per farm basis, 50 of the households with positive farm gross margins grew at least one vegetable crop, while only 25 of households with negative farm gross margins included vegetable crops in their rotation. Farmers have been hesitant to produce primarily for the market given the rudimentary infrastructure and high variability in prices. Farmers reported selling more crops, but when corrected for inflation, gross revenues declined over time. The costs and benefits of developing markets have been unevenly distributed with small holders unable to capitalize on market opportunities, and wealthier farmers engaging in input intensive cash cropping. Farms growing vegetables had an average gross margin of US$137 per year compared to US$12 per year for farms growing only staple crops. However, the area under production is small, and while vegetable production is likely to continue increasing, sensitivity analysis and scenarios suggest high variability and limited short-term impact on poverty alleviation.Sandra Brown is a Senior Research Associate jointly appointed to the Institute for Resources and Environment, University of British Columbia in Vancouver, Canada and the Communities and Watersheds Program at the International Centre for Tropical Agriculture in Cali, Colombia. Her research interests are in gender and equity issues in natural resource management, and linking biophysical and socio-economic research approaches. Sandra works extensively in watershed management both within Canada and internationally. She has worked extensively in the Himalayan and Andean Mountains including current projects in Nepal, China, Bhutan, Peru, Ecuador, and Colombia. Sandra is co-author of numerous multimedia CD-ROMs including: Gender and Resources in the Middle Mountains of Nepal, Integrated Watershed Management, and Water in International Development. She has developed and delivered numerous educational programs including courses on gender and natural resources, watershed management, and innovative technologies in teaching and research. George Kennedy is an Associate Professor in Food and Resource Economics and the Director of International Programs in the Faculty of Agricultural Sciences at the University of British Columbia in Vancouver Canada. His research interests are in agricultural development and internationalizing higher education. Within this capacity, George is the UBC coordinator for the Southeast Asian University Consortium for Graduate Education in Agriculture. In 2002, he won the Association of Universities and Colleges in Canada Award for Excellence in Internationalization for the Global Resource Systems Program in the category Broadening the Student Experience.     

小麦玉米带田根系竞争和补偿效应研究

采用隔根法，对春小麦套春玉米模式根系的竞争和补偿效应进行了研究，试验得出：边行优势是小麦玉米带田增产的重要原因，带田作物竞争因子在低肥水平下主要表现在地下，如小麦、玉米地下贡献率分别占６５９％和６３５％，而随施肥水平的提高，地上因子的贡献率则逐渐增大，如供肥水平由中肥到高肥，春小麦和玉米的地上贡献率分别由５６４％到６２９％和５１７％到５７９％；带田作物根系水平分布呈偏态性，玉米根系偏小麦行向分布达３０～５０ｃｍ；带田根系的垂直分布与单作相似，０～２０ｃｍ土层分布了小麦根重的６３９％～６８９％，玉米根重的７２０％～８１８％。     

丘陵区苹果园边界蜘蛛群落结构与动态的初步研究

用陷阱法对莱阳丘陵区苹果园边界定点调查,初步鉴定该地有游猎性蜘蛛8科18种,其中主要成分依次是:狼蛛科、平腹蛛科、逍遥蛛科和蟹蛛科。研究表明,游猎性蜘蛛在4、5月间主要聚集于边界活动,但6月后随边界植被的长高开始进行生态位扩散。苹果园农事操作后,边界可作为部分蜘蛛的庇护场所,其中以狼蛛科为主。对两段不同植被类型的边界进行了蜘蛛群落调查,发现植被多样化程度高的边界游猎性蜘蛛丰富度和多样性均明显高于植被相对单一的边界。加强边界管理有利于蜘蛛的保护。