博落回水提取物对大肠杆菌攻毒断奶仔猪生长性能、腹泻指数和肠道健康的影响

本试验旨在探究饲粮添加博落回水提取物对产肠毒素大肠杆菌（ETEC）攻毒断奶仔猪生长性能、腹泻指数和肠道健康的影响。试验选取30头28日龄健康“杜×长×大”三元杂交断奶仔猪[体重（8.22±0.98） kg],随机分为3个组,每组10个重复,每个重复1头猪。对照组和模型组饲喂基础饲粮,试验组在基础饲粮的基础上添加1 mL/kg的博落回水提取物。预试期3 d,正试期18 d。在正试期第15天,模型组和试验组每只试验猪灌胃10 mL浓度为2×109CFU/mL的ETEC K88菌液,对照组灌胃同一剂量的无菌LB培养液。结果表明：1）第1～14天（攻毒前）,与对照组相比,试验组断奶仔猪平均日增重显著提高（P <0.05）,料重比显著降低（P <0.05）。第15～18天（攻毒后）和整个试验期（第1～18天）,各组断奶仔猪生长性能无显著差异（P>0.05）。2）攻毒后24 h,与对照组相比,模型组断奶仔猪腹泻指数显著提高（P<0.05）;与模型组相比,试验组腹泻指数略有降低,但差异不显著（P>0.05）。攻毒后48 h,与对照组相比,模型组断奶仔猪腹泻指数显著提高（...     

银杏-杜仲叶发酵物对脂多糖应激肉仔鸡的肠道功能和免疫反应的影响

本试验旨在研究饲粮中添加银杏-杜仲叶发酵物（FGEL）对脂多糖（LPS）应激肉仔鸡的生长性能、肠道结构、消化吸收功能和免疫反应的影响,并与未发酵银杏-杜仲叶（GEL）进行比较。采用2×3双因子试验设计,即2种免疫应激处理（腹腔注射LPS或注射等量生理盐水）和3种饲粮处理（基础饲粮及在基础饲粮中添加0.40%GEL或0.40%FGEL的试验饲粮）。选取1日龄健康爱拔益加（AA）肉仔鸡360只,随机分为6个处理,每个处理均设6个重复,每个重复10只鸡。试验期为21 d。在试验第13、15、17、19和21天,3个应激处理的试鸡腹腔注射500μg/kg BW的LPS,其他3个处理注射等量的生理盐水。在试验第21天最后1次注射后2～4 h进行屠宰取样。结果表明：1）与对照饲粮相比,饲粮添加FGEL的肉仔鸡料重比（F/G）有显著改善（P=0.024）,饲粮添加FGEL显著缓解了LPS应激肉仔鸡平均日增重（ADG）(P=0.023)和血清D-木糖的含量（P=0.011）的降低。2）与对照饲粮相比,饲粮添加FGEL显著缓解了LPS应激肉仔鸡十二指肠（P=0.011）和空肠（P=0.030）的相对重量...     

Morphofunctional description of mucous cells in the gills of the Arapaimidae Arapaima gigas (Cuvier) during its development

The gill structure of the Amazonian fish Arapaima gigas (Cuvier 1829) shows ontogenetic changes during development, particularly due the transition from the aquatic to the obligatory air breathing mode of respiration. However, three main cell types can be found in the gills: mitochondrial rich cells, pavement cells and mucous cells (MCs). The MCs are involved in the secretory pathway. The functions of the secreted molecules include mechanical protection of epithelia, protection against parasites and bacterial infection, and role on ion regulation. In this study, we analysed mucous cell location and mucous cell type, based on pH, during the development of A. gigas. Using samples obtained from the environment, gills were collected and fixed in buffered solution. Histological techniques for the identification of MCs were performed Alcian Blue (AB) and periodic acid‐Schiff (PAS). The results showed the presence of PAS+ and AB+ cells in the whole filament in all examined fish. In animals less than 50 g, few MCs were present, and no differences were observed in AB+ and PAS+ cells. In animals weighing close to 500 g, more PAS+ cells than AB+ cells were observed, and in animals that weighed more than 1,000 g, more AB+ cells than PAS+ cells were observed. These observations may be a result of the ontogenetic changes in the gill epithelia, which can change the osmorespiratory compromise in ion regulation functions as well the glycosaminoglycans secreted by PAS cells, which in large animals can play a role in the protection against parasites and bacterial infection.     

发酵豆粕对断奶仔猪肠道形态及消化酶活性的影响

为研究枯草芽孢杆菌发酵豆粕(FSBM)对仔猪肠道形态及消化酶活性的影响,试验选择初始体重为(7.5±0.5)kg的纯种大白断奶仔猪60头,随机分为两组,对照组饲喂含豆粕(SBM)饲料,试验组饲喂含发酵豆粕(FSBM)的饲料,试验期30d。试验结束时,每组随机选择6头仔猪,收集小肠内三个不同部位的组织样本观察肠道形态,同时采集肠道内容物样品,测定消化酶活性。结果表明:与SBM组相比,FSBM组仔猪小肠三个不同部位的绒毛高度均显著提高(P<0.05),十二指肠隐窝深度显著降低(P<0.05),十二指肠和空肠总蛋白酶和胰蛋白酶的活性显著提高(P<0.05),仔猪胰腺胰蛋白酶活性显著下降(P<0.05)。综上,FSBM能改善断奶仔猪肠道形态和消化酶活性。     

Land Cover Type and Fire in Portugal: Do Fires Burn Land Cover Selectively?

The purpose of this study is to investigate if, or under what conditions, fires select given land cover types for burning. If fires burn unselectively then the land cover composition (the proportional area of various land cover types) of individual fires should approximate the land cover composition available in their neighborhood. In this study we test this hypothesis by performing statistical analyses of a data set consisting of paired vectors with the proportions of land cover types present in burned areas and in their respective surroundings. The statistical methods employed (a permutation technique and the C_max statistic) are commonly used in resource selection studies where data is subject to a unit-sum constraint. The results of the analysis of 506 fires that burned in Portugal in 1991 indicate that fires are selective, with small fires exhibiting stronger land cover preferences than large fires. According to the results of a multiple comparison analysis performed for small fires, there is a marked preference for shrubland followed by other forest cover types, while agriculture is clearly avoided. A similar analysis is performed to test if fire selectivity is related to the ecological region where it occurs. The results obtained in this study contribute to the discussion on the relative importance of fuels as a drivers of fire spread.     

甘蓝细胞质雄性不育材料分子鉴定及花器官形态对核背景的响应

对从国内外引进的15份甘蓝细胞质不育材料进行分子鉴定,并通过多代连续回交转育,研究转育后代花器官形态对核背景的响应。结果发现,15份不育材料中有14份为萝卜胞质不育（Ogu CMS）,仅1份为甘蓝型油菜胞质不育（Nap CMS）。细胞质不育材料花器官对核背景的响应,Nap型主要表现3种类型,第1类与原材料相近或呈负响应,第2类表现为正响应,第3类花器官不同部位响应不一,呈现正或负响应;Ogu型主要表现为不变化或较弱的正响应。不同来源胞质材料的花器形态对同一核背景的响应,因自交系不同而异,对于自交系K1、N4,不同来源胞质材料对其响应趋于一致,对自交系37、F1、G7的响应,在不同来源胞质材料间存在差异。     

铝对芥菜( Brassica juncea Coss) 幼苗根系形态和叶内抗氧化系统的影响

 研究了沙培条件下铝对两个芥菜品种‘雪里蕻’和‘花芥菜’幼苗根系形态和叶生理特性的影响。结果表明, 1 mg·L ^{- 1}和10 mg·L ^{- 1} Al^{3 +}在短时间内能够促进两种芥菜根系生长, 并降低花芥菜叶内MDA的含量。随着铝处理浓度的增加和处理时间的延长, 芥菜根系生长受到抑制, 叶内MDA含量增加, 同时POD和CAT活性升高, 但不同品种芥菜叶内AsA、GSH含量和SOD活性对铝胁迫的反应不同。研究结果说明低浓度铝在短时期内对芥菜生长有促进作用, 但处理时间的延长会抑制芥菜的生长, 在铝胁迫下芥菜体内抗氧化酶活性升高可以提高其铝适应性。     

小叶买麻藤种子营养及药用成分分析

正小叶买麻藤(Gnetum parvifolium(Warb.)C.Y.Cheng)是一种珍贵的药用裸子植物,主要分布在热带、亚热带地区,作为珍稀濒危物种,已被收入中国物种红色名录[1]。作为我国传统中药,小叶买麻藤具有降血压、祛除风湿、止血凉血等功效[2-5]。除此之外,买麻藤属植物中某些种的叶片是非洲等国家重要的出口蔬菜[6],并且种子煮熟后可以食用。小叶买麻藤     

人工模拟增雨对油蒿种子形态性状和比叶面积的影响

【目的】研究油蒿的种子大小和比叶面积对不同增雨处理的响应,探明两者之间的关系,以期揭示油蒿植物功能性状对降水量变化的响应机制和演变趋势。【方法】根据内蒙古磴口县多年平均降水量,在植物生长季5—9月设计4个增雨梯度(25%,50%,75%和100%),对天然油蒿灌丛进行增雨试验,利用Winseedle种子和针叶图象分析软件系统,对比了油蒿种子表型形态特征和比叶面积对降水增多的响应,同时通过相关分析研究了油蒿种子大小与比叶面积的关系。【结果】不同增雨量对油蒿种子长度、宽度、体积、表面积及千粒重均有显著影响,在100%增雨处理下种子各性状指标达到最小值,其中种子宽度、体积、表面积与增雨量呈极显著负相关(P<0.01)。种子长度和千粒重与增雨量呈显著负相关(P<0.05),种子长宽比与增雨量的相关性不显著(P>0.05)。不同增雨量对油蒿比叶面积的影响差异性显著(P<0.05),且随着雨量的增加,比叶面积不断增大。种子大小与比叶面积呈负相关关系,但均未达到显著水平(P>0.05)。【结论】降水增加后油蒿种子会先增加后减小来适应环境变化,通过油蒿种子、比叶面积两大植物功能性状组合对增雨量处理响应的研究体现了荒漠植物应对未来气候变化的生存策略和适应机制。