断奶对仔猪肠道屏障的影响及营养调控     

徐运杰  胡凤娇  全丽萍  苏双良  陈学华  邓敦 《猪业科学》2021,38(1):84-89

在集约化养殖中,3~4周龄早期断奶是仔猪生命周期中一个非常紧张的时期,此时仔猪胃肠道还未发育成熟。肠道屏障由上皮、免疫和肠神经系统组成,这些系统控制上皮屏障的完整性以及肠道功能,包括肠腔营养物质、水和电解质的运输。早期断奶导致肠道通透性增加,出现胃肠功能紊乱的情况,可能对猪只一生产生长期的影响。因此,仔猪断奶饲粮需要正确水平的营养素、营养源和高质量的添加剂,鼓励仔猪快速进食,减轻或消除断奶应激综合症,降低死亡率和发病率。养猪就是养"肠道",合理使用功能性氨基酸、植物化学物质和有机酸等添加剂,能够修复由于断奶应激综合症导致的肠道屏障功能障碍。  相似文献   

Effect of Plasticizers on Properties of Rice Straw Fiber Film     

Chen Hong-rui  Chen Hai-tao  Liu Shuang  Dun Guo-qiang  Zhang Ying 《东北农业大学学报(英文版)》2014,21(4):67-72

In order to improve the properties of rice straw fiber film, one factor contrast test method was employed. Plasticizer type was chosen as input variable, dry tension strength and elongation, wet tension strength and elongation, bursting strength and tearing strength were chosen as indexes. The results showed that there were significant differences among the means of dry tension strength, dry elongation and bursting strength of different plasticizers; there were not significant differences among the means of wet tension strength, wet elongation and tearing strength of different plasticizers; for dry tension strength and elongation, glycerol had a significant difference with sorbitol and PEG, no significant difference was observed between sorbitol and PEG, dry tension strength added glycerol had been reduced 6.8% compared with that added sorbitol, reduced 9.5% compared with that added PEG; elongation had been improved 6.1% and 9.4%, respectively; for bursting strength, sorbitol had a significant difference with glycerol and PEG, no significant difference was observed between glycerol and PEG; bursting strength added glycerol and added PEG had been improved 6.9% and 5.6%, respectively compared with that of the added sorbitol. The results provided a theoretical reference for further improving the straw fiber film manufacturing process.  相似文献   

南宁市双色中华蜜蜂探析     

蒋得德  罗敦 《蜜蜂杂志》2019,(8):32-33

近几年来,南宁的许多中华蜜蜂(以下简称中蜂)养殖场经常出现麻色蜜蜂和黄色蜜蜂混同一起的种群(简称双色群),引起中蜂养殖者的高度关注。笔者在南宁市吴圩镇(广西国有七坡林场)定地养殖中蜂十余年,每年都有少量双色蜂种群出现,为此对双色中华蜜蜂进行了详细观察、记录、验证,认为双色蜂不是一个独立品种,是外来黄色蜂种与本地麻色蜂种杂交的结果。  相似文献   

不同源壳聚糖对鲫生长和抗感染能力的影响   总被引：1，自引：0，他引：1  

翟少伟  王敦 《水产科学》2009,28(8)

将180尾平均体质量(25.1±1.5)g/尾的鲫随机分为3个处理组,饲喂3种饲料(基础饲料、基础饲料+0.50%普通虾蟹壳壳聚糖、基础饲料+0.50%昆虫壳聚糖),每个处理组4个重复,每个重复15尾,研究不同源壳聚糖对鲫生长和抗嗜水气单胞菌感染能力的影响.试验结果表明,添加昆虫源壳聚糖显著提高了鲫的特定生长率,显著降低了饵料系数(P< 0.05),昆虫壳聚糖处理组的生长性能高于普通壳聚糖处理组(P< 0.05);壳聚糖的添加显著提高了鲫抗嗜水单胞菌感染的半致死浓度LD50(P< 0.05),昆虫壳聚糖处理组的LD50高于普通壳聚糖处理组(P< 0.1).  相似文献   

泵闸结构流场的水力特性     

黄建军  郑源  张盾 《排灌机械》2010,28(2):149-154

为了提高泵闸工程工作的稳定性和高效性,采用计算流体动力学方法,以设计参数作为控制条件,运用Fluent软件对某泵闸工程进行了数值模拟计算和分析,并对闸门附近的结构进行了优化.结合河道过流特点,建立了断面有效过流面积率和过流均匀度两个表示过流断面水流流态的公式,并以此作为数值模拟优化的目标函数,对泵闸结构进行了优化.通过数值模拟,分析了引、排水工况下的水流及流场分布规律,分析了实际闸门附近的水流动特性和过流情况,分析了内河侧＂S＂形转弯对工程水流的影响.通过整体水工模型试验,对改造后的消能设施进行了论证.结果表明,改造后的内外河最大流速均小于0.6~0.8 m/s,且河道的有效过流面积率和过流均匀度均大于0.75.  相似文献   

苦马豆的组织培养与快速繁殖   总被引：1，自引：0，他引：1  

郭刚  卢跃敏  张晓宏  付习科  马盾  周小云 《新疆农业科学》2014,51(1):118-123

[目的]研究苦马豆的组织培养与快速繁殖的方法.[方法]以苦马豆上胚轴为外植体,MS为基本培养基,通过不同的激素种类和浓度配比,建立苦马豆组培快繁体系.[结果]组织培养与快速繁殖的培养基为:诱导愈伤培养基为MS+6-BA2.0mg/L+2,4-D 0.25 mg/L;继代培养基为MS+6-BA 2.0 mg/L+NA.A0.5 mg/L;诱芽培养基为MS+NAA 0.05 mg/L+ZT0.05 mg/L+AC 0.1;;生根培养基为1/2 MS+ IBA1.5 mg/L+蔗糖(Suc)3;.该组培苗适宜移栽于珍珠岩+蛭石(1∶1)基质中,平均成活率80;.[结论]筛选获得适宜苦马豆上胚轴为外植体的组培快繁的培养条件,为苦马豆快繁体系的建立探索出了一条新的有效的途径.  相似文献   

博落回生物碱的研究进展     

邓敦  邓跃林 《家畜生态》2009,(4)

博落回是一种具有多种用途的中草药,广泛应用于消炎、抗癌及饲料、兽药和农药等方面。通过对博落回的主要成分、博落回的药理研究及其在畜牧业中的应用等方面进行综述,以亟为生产实践提供参考。  相似文献   

陆地棉矮化突变体及其SSR指纹分析   总被引：6，自引：2，他引：4  

周小云  陈勋基  马盾  黄乐平  黄全生 《新疆农业科学》2009,46(4):761-763

、纤维品质,推动棉花生产的全面机械化和现代化有重要的现实意义.  相似文献   

施肥和播种量对扬州地区苜蓿生长特性和产草量的影响     

潘玲  魏臻武  武自念  张栋  郑曦  陈斐  刘倩  李伟民 《草地学报》2012,20(6):1099-1104

用裂区试验设计研究扬州地区苜蓿(Medicago sativa)不同播种量和施肥水平对产草量及生产性能的影响。结果表明:江淮地区苜蓿推荐播种量为18.75 kg·hm^-2,氮、磷、钾推荐施用量分别为23,113,68 kg·hm^-2时,此时苜蓿的理论产草量可达22858.25 kg·hm^-2。单独施用氮、磷、钾肥时,在一定范围内对苜蓿产草量有促进作用,但当超过最大施用量时,对苜蓿的生长反而造成抑制。建议氮肥施用量不超过30 kg·hm^-2,磷肥施用量不超过130 kg·hm^-2。氮、磷、钾共同施用时苜蓿产草量才能达到最大值;氮肥在苗期、分枝期和初花期对苜蓿植株生长均有一定的促进作用;磷肥促进苜蓿主枝数的增加,氮钾肥有利于苜蓿侧枝数的生长。  相似文献   

Effect of Isomaltooligosaccharide Syrup on Quality Characteristics of Sponge Cake     

Ching‐Ching Lee  Hsueh‐Fang Wang  Sheng‐Dun Lin 《Cereal Chemistry》2008,85(4):515-521

Sponge cakes were formulated using isomaltooligosaccharide (IMO) syrup as a sweetener to replace 0, 25, 50, 75, and 100% sucrose. The qualities of cakes were evaluated by physicochemical, microbiological, and sensory evaluation analyses. The viscosity in cake batter, cake volume, crumb Hunter a value, and IMO contents of baked cakes increased with increasing IMO syrup level, whereas the specific gravity in cake batter, crust L a b, and crumb L and b values, and hardness of baked cakes showed a reverse trend. The crust and crumb of cakes became darker and less yellow and had a better tender and less sweet texture as IMO syrup level increased and sucrose decreased. The degree of overall liking of cakes increased with increasing IMO syrup level. Total plate counts exceeded 10⁵ CFU/g for cakes stored at 25°C for three days and <10³ CFU/g for the samples stored at 5°C for seven days. The changes in the moisture content, water activity, L a b values, and IMO contents of samples did not differ during storage. Overall, sucrose in the formulation of sponge cakes could be partially or fully replaced with IMO syrup.  相似文献