香鱼的营养需要

本文就国内外关于香鱼对饲料中蛋白质、不饱和脂肪酸、磷脂及维生素等营养需求的研究进行概述。     

肉鸭对杂粕型日粮烟酸的需要

本试验采用单因子试验设计，选择10日龄健康樱桃谷肉鸭240只，按性别相同，公母各半，体重相近的原则随机分为4个处理，每个处理4个重复，每个重复15只，根据玉米一杂粕型日粮中不同烟酸含量（40ppm、60ppm、80ppm及1OOppm）分别饲喂试验肉鸭至31日龄。10～17日龄以烟酸含量为60ppm日增重较好，以烟酸含量为1OOppm日粮的料肉比较好；10～24日龄以烟酸含量为60ppm日粮日增重较好，烟酸含量为40ppm的料肉比较好；10～31日龄以烟酸含量为80ppm日粮日增重和料肉比较好。     

妊娠母猪的营养需要研究进展

本文综述了妊娠母猪对能量、氨基酸、维生素、纤维素的适宜需要量及其对生产性能的影响。     

渭干河—库车河三角洲绿洲种植业需水分析

采用FAO-PM公式,参照毗邻地区的灌溉试验成果和当地群众的灌水经验,结合土壤供水量和不同作物对地下水的利用量,根据渭干河-库车河三角洲绿洲区域2005年的作物种植面积,计算该区农作物的总需水量.结果表明:渭干河-库车河三角洲绿洲农作物需水量总计8.01×108 m3,农作物需水量占河道来水量的28.49%.作物总需水中粮食作物需水量占37.22%,经济作物的占59.35%,饲料作物的占3.43%.粮食作物需水定顿较经济作物和饲料作物高,就具体作物而吉,水稻、蔬菜、冬小麦、棉花、苜蓿、油菜等需水定额较高,玉米、瓜类和薯类等较低.各县单位面积需水量差异不大,平均值为5 890.35 m3/hm2,库车县最高,为6 035.32 m3/hm2,沙雅县最低5 746.37 m3/hm2.农业需水量与作物结构密切相关.农业用水浪费严重,使渭干河-库车河三角洲绿洲农作物实际用水量远高于其需水量的理论计算值.     

Rootstock effect on budburst of ‘Premier’ low-chill peach cultivar

To determine the effect of rootstock with different chilling requirements on the bud break of the low-chill ‘Premier’ peach cultivar (150 CH), the trees grafted on ‘Newbelle’ (150 CH) and ‘O’Henry’ (750 CH) seedling rootstocks were forced in a glasshouse after being subjected to 100, 200 and 300 CU chilling. The percentage of flower bud burst was slightly higher on ‘Newbelle’ than on ‘O’Henry’, although the difference was not significant. There was little leaf bud burst with 100 CU chilling on both rootstocks. With 200 and 300 CU chilling, the percentage of leaf bud burst and the total leaf number per tree was higher on the ‘Newbelle’ than on the ‘O’Henry’ rootstocks.     

Mast cells change cellular cholesterol content and inhibit cholesterol efflux from THP-1 macrophage-derived foam cells

AIM:Mast cells (MC) are present in the arterial intima,the site of atherogenesis. The present studies explore the effect of MC on cholesterol content,distribution and efflux in THP-1 macrophage-derived foam cells (THP-1FCs）. METHODS:THP-1FCs were incubated with high-density lipoproteins 3 (HDL₃) in the absence or presence of mast cell granules (MCGs) harvested from compound 48/80-stimulated rat peritoneal MC. The intracellular cholesterol level,cholesterol effluxing capacity,ATP-binding cassette transporter A1(ABCA1) mRNA and HDL₃ treated with MCGs were detected to characterize the role of MC on intracellular cholesterol. RESULTS:MCGs had high levels of cellular total cholesterol(TC),free cholesterol(FC) but not esterifed cholesterol(EC) compared to control group where the TC concentrations ranged from 527.3 mg/g to 917.9 mg/g cellular protein with EC accounting for 7.6% of the cholesterol. Cholesterol efflux was 14% less in MCGs group compared to control group. ABCA1 mRNA expression in MCG-treated THP-1FCs remained unchanged in 20 hours. In contrast,treatment of HDL₃ with MCGs resulted in rapid degradation of the main HDL₃ apoliproteins,apoA-Ⅰ. SDS-PAGE revealed that a minor polypeptide band with about 26 kD molecular mass appeared below the apoA-Ⅰband. Densitometric analysis of the gel demonstrated that ≈ 28% of apoA-Ⅰhad been degraded by the MCGs. CONCLUSION:These results indicate that MC decreases cholesterol efflux,increases cellular accumulation in TC and FC by depleting HDL₃ and apoA-Ⅰ,but not by inhibiting ABCA1 mRNA expression.     

铜与柠檬酸不同配伍对断奶仔猪生产性能与血液生化指标影响的研究

选用杜洛克×长白×大约克三元杂交品种，35日龄断奶的仔猪72头进行试验。试验采用随机区组设计，共设8个组，其中设添加1%柠檬酸和添加250 mg/kg铜2个对照组，铜与柠檬酸的不同组合为6个处理组，每组设3个重复，每个重复3头仔猪。试验结果表明：①日粮中添加高铜与柠檬酸的不同配比均可以不同程度地提高日增重、饲料利用率与降低仔猪腹泻率；②日粮中添加高铜与柠檬酸可以促进高铜的代谢和吸收，有较好的生态效应； ③ 总体上铜与柠檬酸各组合对仔猪的各项血液生化指标影响不明显，基本上处于正常的生理值范围内；④ 高铜与柠檬酸有明显的互作效应，本试验以150 mg/kg高铜和1.5%柠檬酸的组合效果最好。     

田间供水与杨树生长关系的研究* Ⅱ.田间供水、蒸腾耗水与材积产量的关系分析及林木需水量的估算

在集约栽培的杨树人工林中进行小区灌溉试验,研究了不同供水处理下林木生长和水分生理指标的变化,分析了田间供水量、蒸腾耗水量和材积产量的关系。结果表明,林木蒸腾耗水量和材积年产量均随供水水平的高低而增减。5年生杨树人工林(林行距3×6 m)在5—10月的蒸腾耗水量约602.6—879.2mm,林木生长1m~3 材积需蒸腾消耗180.0—215.0 t水。作者还用多种模式分析了田间供水量与材积产量的相关关系,提出了估算杨树人工林需水量的方法和 Ⅰ-69杨人工林需水量表。     

Ecological factors controlling the abundance of non-native invasive black cherry (Prunus serotina) in deciduous forest understory in Belgium

The relation between invasion success of Prunus serotina and type of recipient habitat was studied in a large forest in central Belgium. The major emphasis in this study was the determination of factors controlling the abundance of P. serotina in understory strata. Environmental variables measured in 34 sample plots were slope, aspect, litter depth, soil type, pH, soil compaction, soil moisture, air humidity, soil temperature and light intensity in spring and late summer. Site conditions were also expressed indirectly for 210 sample plots using Ellenberg indicator values (soil nutrients, acidity, moisture, light conditions). Plots with P. serotina had lower mean indicator values for soil moisture, reaction (pH) and nitrogen, compared to plots without P. serotina. Twenty indicator species were identified for plots in which P. serotina occurs. The species richness of the herb layer was negatively correlated with the percentage cover of black cherry in the shrub layer. The percentage cover of P. serotina saplings in different overstory types was ranked as follows: Quercus > Pinus > Fagus > logging areas. Only three variables explained significant amounts of variation in Prunus abundance: slope, light intensity at 120 cm in April and light intensity at ground level in September. We found a positive response of black cherry seedlings to light intensity between 58 and 80% of full light (April measurements at 120 cm), while saplings showed a negative response within this range. Between 21 and 47% of full light (April measurements at 120 cm), seedlings were poorly represented whereas saplings showed a quite high cover. Between 0.3 and 1.8% light (September measurements at ground level), seedlings were almost absent while saplings maintained a high abundance. The results suggest that P. serotina shows a differential response to light intensity in relation to its development stage, i.e. the species is heliophilous at the seedling stage and becomes a shade plant at the sapling stage.     

牡丹‘洛阳红’芽休眠低温解除中需冷量和生理生化动态变化

以4年生牡丹‘洛阳红’为试验材料,经历0～42 d低温处理观测其芽萌动成花情况,探讨上海地区牡丹花芽低温休眠解除过程中需冷量和生理生化指标的动态变化规律.结果表明:处理7d为低温累积期,处理14 d即可启动休眠解除但萌动率(52.8％)和成花率(27.8％)均较低;基本解除休眠需要21 d低温处理,萌动率可达90.3％,但成花率为51.6％;而彻底解除休眠则需要至少低温处理28 d,成花率急剧增加至71.8％.花芽中可溶性蛋白和可溶性糖的变化趋势类似:休眠完全解除前随着低温累积量的增加急速增加,彻底解除后随着需冷量的增加变化趋缓.花芽内源激素及其比值的动态变化表明,GA3和ABA的含量变化与花芽体眠解除的进程分别呈显著的正、负相关;在基本与彻底解除休眠区间内二者含量急剧变化,GA3/ABA的值可以直接显示花芽休眠的程度.进一步证明GA3是最为重要的促进休眠解除激素,而ABA则是休眠解除的主要拮抗物.