n-3/n-6长链多不饱和脂肪酸对大菱鲆幼鱼脂肪沉积、脂肪吸收及代谢相关酶活性和血清生化指标的影响          下载免费PDF全文

谭青  韩秀杰  王际英  李宝山  李学丽  郝甜甜  张利民 《渔业科学进展》2018,39(4):66-73

为探讨饲料中不同n-3/n-6长链多不饱和脂肪酸(LC-PUFA)对大菱鲆(Scophthalmus maximus)幼鱼生长性能及饲料利用、体组成和消化酶的影响,配制了6种不同n-3/n-6 LC-PUFA比值(29.54,D1组;23.04,D2组;18.97,D3组;9.06,D4组;6.86,D5组;3.87,D6组)的实验饲料。以大菱鲆幼鱼[(12.18?0.01)g]为研究对象,在循环水养殖系统中开展了为期56 d的养殖实验。结果显示,n-3/n-6 LC-PUFA对大菱鲆幼鱼的成活率(SR)无显著影响(P0.05);增重率(WGR)随着n-3/n-6 LC-PUFA的降低呈先上升后下降趋势,D6组显著低于其他各组(P0.05);脂肪沉积率随着饲料中n-3/n-6 LC-PUFA的降低呈下降趋势,且D6组达到最小值,为14.80,显著低于其他各组(P0.05)。随着饲料中的变化,胰蛋白酶的活性呈先增强后减弱的趋势,且在D4组时达到最大值;脂肪酶活性呈上升趋势。随着饲料中n-3/n-6 LC-PUFA的变化,脂肪酸合成酶活性呈先上升后下降的趋势,最高值为D4组,显著高于其他各组(P0.05);葡萄糖-6-磷酸脱氢酶的酶活呈先上升后下降的趋势,D3组为最大值,显著高于其他各组(P0.05)。随着饲料中n-3/n-6 LC-PUFA的降低,谷草转氨酶呈先上升后下降的趋势;总蛋白、白蛋白和高密度脂蛋白胆固醇均随着饲料n-3/n-6LC-PUFA的变化呈先上升后下降的趋势,均在D5组时达到最大值。研究表明,饲料中n-3/n-6LC-PUFA的比例降低会导致大菱鲆幼鱼的脂肪沉积率降低。  相似文献   

武夷山自然保护区景观格局指数的尺度效应分析   总被引：2，自引：0，他引：2  

张春英  林从华  洪伟  吴承祯  何春玲  陈莺娇 《浙江林学院学报》2009,26(6):877-883

采用变换矢栅转换过程中像元尺度的方法,对福建省武夷山自然保护区景观格局指数的尺度效应进行分析．并利用分维数方法选取最佳的像元尺度值。结果表明：蔓延度指数、邻近相似度指数、破碎度指数和多样性指数都是随着像元尺度的增加而单调递减,递减的速率在10～50m区间上较快,在50～500m区间的减少较慢;连接度、结合度、均匀度和优势度指数随着像元尺度的增加出现了各自不同的变化曲线;对武夷山自然保护区而言,矢栅转换的像元尺度选择30m较为合理。  相似文献   

基于介电特性的果蔬无损检测系统构建   总被引：1，自引：0，他引：1  

秦刚  宋海燕 《山西农业大学学报(自然科学版)》2009,29(4):358-360

随着人民生活水平的不断提高,对果蔬分级和内部品质的要求也越来越显得重要。利用果蔬电特性检测方法进行果蔬分级,既能满足检测设备结构简单,价格便宜,且系统数据信号采集和处理方便,又能保持果蔬内部品质不受影响。试验采用介电特性法对果蔬品质无损检测测量原理,构建了一种果蔬无损检测系统,并对不同新鲜度的苹果在低频段进行了试验检测。结果表明,在20Hz~200kHz测试频率范围内,随着果蔬新鲜度的下降,其等效阻值趋于增大,且按一定规律变化,表明该系统的设计构造是简易可行的。  相似文献   

Fe、Zn、Cu不同组合对岩原鲤生长、体组成和血清生化指标的影响     

汪福保  罗莉  张桂众  颜忠  刘本祥 《淡水渔业》2009,39(4)

试验选用体长(8.16±0.14)cm,体重(7.91±0.12)g的岩原鲤(Procypris rabaudi),经76 d的养殖试验,研究添加Fe、Zn、Cu不同组合水平的7组实用日粮对岩原鲤生长、体营养组成和血清生化指标的影响。试验鱼种630尾,随机分成7个组,每组3个重复,每个重复30尾。结果显示:饲料中添加Fe、Zn、Cu能够提高岩原鲤的生长性能和抗氧化能能力。当Fe、Zn、Cu的添加量分别为140、50、5 mg/kg时,增重率、特定生长率、饲料蛋白质效率、超氧化物歧化酶(SOD)活性和总抗氧化能力(T-AOC)最高,饲料系数最低。适量添加Fe、Zn、Cu能够显著提高岩原鲤的免疫能力。当Fe、Zn、Cu的添加量分别为200、90、4 mg/kg时岩原鲤血清溶菌酶活力最高。结果表明,岩原鲤饲料中Fe、Zn、Cu的最适添加量分别为140、50、5 mg/kg。  相似文献   

Individual tree growth response to variable-density thinning in coastal Pacific Northwest forests     

Scott D. Roberts  Constance A. Harrington 《Forest Ecology and Management》2008

We examined 5-year basal area growth of nearly 2600 trees in stem-mapped plots at five locations differing in site characteristics, species composition, and management history on the Olympic Peninsula in Western Washington, USA. Our objectives were to determine if internal edges, the boundaries within the stand between components of the variable-density thinning, influenced individual tree growth, and whether incorporation of individual tree local competition indices in growth prediction models could account for treatment and edge effects. Treatment significantly affected tree growth at all sites, with trees in the thinned matrix displaying on average over 25% greater basal area growth than trees in unthinned patches. Proximity to canopy gaps created as part of the variable-density thinning increased basal area growth of trees in the thinned matrix by nearly 11%. In addition, growth of trees close to skid trails was 11% greater than trees located away from the trails. Past thinning history, and its effect on initial stocking rate, appeared to affect the magnitude of the edge effects. Blocks that had received earlier commercial thinnings, and thus had lower stocking at the onset of the study, displayed lower growth responses than previously unthinned blocks. Including local competition indices in the models generally reduced growth prediction error; however, the indices examined did not fully account for treatment or edge effects. Our results suggest that not accounting for internal edges in spatially complex stands could result in errors in projected growth of trees, although these edge effects are highly variable. Failure to account for the effects of internal edges could affect not just estimates of future stand yield, but also projections of future stand structure.  相似文献   

虚拟仪器在木质材料无损检测中的应用     

王逢瑚  张海峰  朱晓冬 《林业机械与木工设备》2008,36(7)

虚拟仪器是基于计算机的仪器,计算机和仪器密切结合是当前仪器发展的一个主要方向.将Labview软件与计算机有效结合,进一步开发用于木质材料无损检测的虚拟仪器,将满足木质材料振动信号采集、实时处理与存储等多方面的需求.  相似文献   

甘草次酸对早期断奶仔猪血液挥发性脂肪酸和血液生化指标的影响     

何子双  胡元亮  黄瑞林  印遇龙 《广东农业科学》2008,(2):76-77,82

研究了甘草次酸对早期断奶仔猪血液挥发性脂肪酸和血液生化指标的影响,结果表明,与不添加甘草次酸对照组相比,甘草次酸组仔猪14日龄时血液中的丙酸、异戊酸和总挥发性脂肪酸浓度显著提高,21日龄时丙酸显著提高,丁酸、异戊酸显著降低.说明甘草次酸影响了仔猪的脂肪代谢,提高14日龄、降低21日龄仔猪血液中的挥发性脂肪酸浓度;此外,甘草次酸对仔猪血液中的尿素氮、氨、葡萄糖、总蛋白、白蛋白、球蛋白、总胆同醇等生化指标没有明显影响.  相似文献   

河北省卧龙山庄旅游规划及规划前后景观变化评价研究     

张红霞  秦安臣  杜彦超  张艳红  肇丹丹  赵志江 《中国农学通报》2008,24(7):413-418

由于卧龙山庄原规划已时过境迁,已经不能满足需要,因而急需进行重新规划和对规划后的方案进行系统评价。该文通过实地调查、GPS定位相结合的方法查清了现有旅游资源并在此基础上进行了规划,然后运用景观生态学方法对规划后的方案进行了评价。该文规划种植了酸枣、冬枣、梨枣、月光枣、野菜、柿子、欧李,改变了蔬菜园的种植种类;增加了杜梨、栾树和红叶臭椿的种植面积;规划了生态集雨工程示范点、火箭消雷展览室、卧龙禅寺、金鱼池、观鱼长廊、商店、观景亭、道路、停车场和厕所等。用斑块水平和景观水平上的景观指数作为规划方案评价的数量指标,对规划后的效果进行评定,认为规划后虽然景观破碎化指数提高了,但景观类型集中度加强;景观多样性指数、优势度指数、丰富度均提高了,美学质量得到改善,旅游设施更为完善,游览期更长;同时认为这种评价方法在规划方案筛选中具有一定的可行性和参考性。  相似文献   

Toxic effects of annonaceous acetogenins from <Emphasis Type="Italic">Annona cherimolia</Emphasis> (Magnoliales: Annonaceae) on <Emphasis Type="Italic">Spodoptera frugiperda</Emphasis> (Lepidoptera: Noctuidae)     

O. Álvarez Colom  A. Neske  S. Popich  A. Bardón 《Journal of pest science》2007,80(1):63-67

Plants belonging to the family Annonaceae have been commonly described in traditional medicine as remedies against head lice, and for their insecticidal properties. Characteristic constituents from a few genera of these plants are the annonaceous acetogenins. Fourteen annonaceous acetogenins have been isolated from our Argentine collection of the seeds of A. cherimolia. We report herein the antifeedant and insecticidal effects of nine of those acetogenins on Spodoptera frugiperda (J. E. Smith). The acetogenin squamocin, one of the major constituents of the extract, displayed toxic effects on early larval instars when incorporated to the larval diet at a dose of 50 μg per g of diet. The remaining annonaceous acetogenins tested, itrabin, asimicin, neoanonin, cherimolin-1, cherimolin-2, almuñequin, motrilin, and tucumanin produced pupal mortality and adult malformations leading to death, when incorporated to the larval diet at the same dose. The evaluation of indices of food consumption, growth, and food utilization indicated that squamocin was the only tested acetogenin to produce significant decrease in the growth rate and to reduce the efficiency with which larvae converted ingested food into biomass. All the acetogenins produced more than 80% pupal mortality with no dependence on the position of the THF rings or the number and location of the OH groups.  相似文献   

近等基因系抗旱性小麦氮素营养遗传性状的研究 Ⅳ.硝酸还原酶活力与小麦抗旱性指标的研究     

樊小林  李玲  何文勤  汪沛洪 《华南农业大学学报》1998,(4)

用盆栽试验在无氮（Ｎ０）、每公斤土壤０．１５ｇ氮（Ｎ１）、０．３０ｇ氮（Ｎ２）和干旱胁迫（正常供水Ｗ１、轻度干旱Ｗ２、中度干旱Ｗ３、重度干旱Ｗ４）以及品系抗旱性差异（ＴＡＭ品种的高抗Ｖ１和低抗Ｖ３）的条件下研究冬小麦抗旱性和硝酸还原酶活性（ＮＲＡ）的关系。结果表明,近等基因系抗旱性小麦高抗（Ｖ１）和低抗（Ｖ３）品系孕穗期功能叶ＮＲＡ存在显著的差异,在Ｗ２到Ｗ４的干旱胁迫过程中,Ｖ１的ＮＲＡ大于Ｖ３。Ｎ１下Ｖ１的ＮＲＡ也大于Ｖ３。对品系、干旱胁迫、氮肥３因素试验结果,通过把同一品系同一水分处理的ＮＲＡ平均消除氮素的干扰;把同一品系同一氮肥处理的ＮＲＡ平均消除水分的干扰的结果分别证明,在中等氮肥水平内,任何干旱强度（轻度、中度、重度干旱胁迫）下,高抗小麦Ｖ１的ＮＲＡ＞低抗小麦Ｖ３的ＮＲＡ。在此条件ＮＲＡ作为抗旱性的指标。同时Ｖ１和Ｖ３可用于筛选小麦抗旱的形态学、生理和生化指标。  相似文献