Examination of non-genetic factors affecting the growth performance of djallonke sheep in soudanian zone at the Okpara breeding farm of Benin

A study was carried out at the Okpara breeding farm in Benin. Records on 558 lambs of the Djallonke sheep breed, born from 1997 to 2000, were used to determine the weekly growth curve from birth up to 119 days of age. Non-genetic factors affecting lamb weights at birth and at 30, 60, 90 and 120 days and average daily gains from 0 to 30 days, from 0 to 60 days, from 0 to 90 days and from 0 to 120 days were investigated. A linear model comprising the fixed effects of birth season, birth year, parity number of ewe and sex of lambs was used for analysis of variance by least squares. All fixed effects were significant for weight at 30 and 60 days and average daily gains at 30 days, with the exception of the parity of the ewe for birth weight, weight and average daily gain at 90 days. All fixed effects tended to cancel out for weight and average daily gains by 120 days. Lambs born in the dry season were the heaviest. Single lambs and male lambs were heavier than twins and females. Lambs from ewes of 3rd and 4th parity were heavier, with higher, average daily gains.     

Body weight changes and subsequent lambing rates of western whiteface ewes grazing winter range

The objective was to describe body weight change (BWC) and subsequent lambing performance of Columbia, Polypay, Rambouillet, and Targhee ewes that grazed shrub-dominated range in winter of 1989, 1990, and 1991. In December (winter), after breeding each year (yr; October to December), ewes were moved to range. Depending upon severity of climatic conditions and vegetation accessibility, ewes grazed winter range for 30 to 60 days (d). Body weights were measured 2 d before grazing commenced (initial) and 2 to 7 d after ewes were transported off range (exit). Total BWC was calculated by subtracting finial BW from initial BW. All data were analyzed within each breed, as repeated measures using mixed models with age and year included in the model. For all breeds, 2-yr-old ewes were lightest going on to winter range and had the lowest lambing rate. Ewes lost weight while grazing winter range, but mature BW, once achieved, was restored annually with the exception of the 7-yr-old Columbia and Targhee ewes. Regardless of breed or age, ewes were able to achieve lambing rates > 1.5 lambs following early- and mid-pregnancy weight loss. Lambing rates were greater in older ewes, which generally experienced substantial negative BWC during winter grazing.     

学生评教可靠性分析

在综合分析学生考试成绩和学生对相应任课教师的评价结果的1219组数据基础上,对学生评教结果的可靠性及其与考试成绩的相关性进行了客观地分析。结果表明：部分学生在评教过程中表现出很大的随意性;优秀学生的评价结果比较可靠;学生评教结果与其单门课程的考试成绩之间不相关,但学习成绩好的学生群体为教师打分高于学习成绩中等和差的学生。因此,应从充分考虑参评学生的权重系数、适当简化评价指标和加大对评教工作的宣传力度三方面来完善学生评教工作。     

基于熵权法的粮食产量影响因素权重确定

选取乡村从业人员数量、农业机械总动力、农作物有效灌溉面积、粮食作物播种面积、化肥施用量、农村用电量、受灾面积和成灾面积等8个主要因素作为粮食产量影响因素,运用熵权法给出了粮食产量影响因素权重确定方法,并运用1985～2005年相关数据,实例分析了我国粮食产量影响因素的权重。结果表明,农村用电量对粮食产量的影响最大,其次是农业机械总动力、化肥施用量和成灾面积。要提高粮食产量,必须加大机械化程度,将人从以往的直接耕种过程中解放出来,并要加强水利工程建设,做好防灾减灾工作。     

生物灭鼠新探索—制备芸香毒饵降低小鼠生育的实验研究

芸香（Rutag raveolens）是一种药用植物,有良好避孕效果,制成植物灭鼠剂,为植物灭鼠剂的大批量生产和应用提供理论基础。实验把芸香全草包煎制成水煎剂,制成毒饵,孕前和孕后分别饲喂小鼠,观察体重变化、怀孕率和流产率。统计分析结果,毒饵组与对照组比,体重变化差异不显著,怀孕率明显降低,流产率明显增高。结论：芸香毒饵可以有效的抑制小鼠繁殖速度。     

高校图书馆用户满意度评价指标体系的构建及权重的测定

通过对国内外用户满意度指标的调查,采用了定性分析与定量分析相结合的方法,构建出一套适用于高校图书馆服务评估的综合指标体系。并且利用网络调查法与Expert Choice软件,科学的计算出了每个指标的权重。     

Reliability of volumetric sampling as compared to weighed samples in quantitative soil test interpretations

Abstract

Weight variability of volumetric soil test samples taken with the standard 4.25 cm³ Urbana Laboratories’ soil scoop was studied as a factor influencing soil test accuracy. Also examined was effect of degree of sample pulverization on volume—weight, differences among technicians, and volume‐weight differences between dry and moist samples.

The results revealed that volumetric sampling of Maine soils can lead to major errors, particularly when quick tests are used to quantify lime requirement, extractable H, exchangeable cations, CEC, and percent base saturation. Good predictions of these properties from quick soil test results, however, are possible when samples are weighed. In the Maine Laboratory poor quantitative results from volumetric samples originated from wide variations in volume‐weight among soils. This variability was traced to degree of aggregation, which in turn was traceable to differences in texture and organic matter among samples. Technician differences were not an important source of volume‐weight variability. Volume‐weights were much lower with moist than with dried soil, but volume‐weight variability among soils was less when sampled moist.     

芬兰纯种蓝狐仔公狐体重增长的试验

为了研究探讨芬兰纯种蓝狐仔公狐生长发育的特点及规律 ,摸索和总结其育成期的饲养管理经验 ,对 1 999年出生的 2 4只芬兰纯种仔公狐进行了 1 2 0d的试喂。结果表明 ,芬兰纯种仔公狐具有生长周期长、生长发育快、营养需要强度大等特点。生长最佳期为 5月龄 ,生长最快的为 3月龄。育成结束后 ,有 75%的仔公狐达到了芬兰种狐的标准     

Factors related to the risk of neonatal mortality,birth-weight and serum immunoglobulin concentration in lambs in the UK

Neonatal-lamb mortality represents an economic loss and welfare concern. Two factors often associated with the risk of mortality are birth-weight and serum immunoglobulin concentration. We used data from two studies to investigate risk factors for mortality between 2 and 14 days of age and factors affecting birth-weight and serum immunoglobulin concentration at 48 h of age. Dataset 1 included 1339 lambs born on eight farms during the 1995 spring lambing season; dataset 2 included 3172 lambs on seven farms during the 1991 spring lambing season. To account for some of the potential clustering within the data, multilevel models were used. Most (>75%) of the variation in the risk of mortality was at the lamb level. In dataset 1, factors significantly associated with increased odds of lamb mortality included low birth-weight and low serum immunoglobulin concentration. In dataset 2, significant risk factors for mortality included low birth-weight, ewe body-condition score, being born late in the season (relative to other lambs on the farm) and being born in multiple litters. There was a significant interaction between the effects of litter size and birth-weight. (Serum immunoglobulin concentration was not available for dataset 2.) More than half of the variation in birth-weight was at the ewe level, 27% at the lamb level, and 18% at the farm level (dataset 1). Single birth and being male were associated with increased birth-weight in both datasets. In dataset 2 only, increasing ewe condition score and birth early in the study period were also associated with increased birth-weight. Fifty-six percent of the variation in immunoglobulin concentration was at the lamb level, 36% at the ewe level and only 7% at the farm level. Factors associated with reduced serum immunoglobulin concentration included early or late birth in the lambing season, being born later than 14 days after the first lamb born on the farm, multiple-birth litters and maternal mastitis.     

木材阻燃耐久性研究

研究了ＰＮＢ阻燃体系的阻燃耐久性问题。研究结果,试件在流动水中浸泡一天失重率为未浸泡前的７倍,有焰燃烧时间和无焰燃烧时间由零增加到１８０ｓ和６５０ｓ,损毁长度率为１００％,与未经阻燃处理的试件相同。利用脲醛预缩液与ＰＮＢ混合浸注木材,干燥处理后,在流动水中浸泡７嵦欤е芈始负趺挥斜浠醒嫒忌帐奔浜臀扪嫒忌帐奔浔３治悖鸹俪ざ嚷事杂性黾印Ｋ得麟迦┰に跻憾蕴岣咦枞继逑档目沽魇杂幸欢ㄗ饔茫瑣从而提高了木材阻燃的耐久性。