不同分子量壳寡糖对黑麦草种子萌发和幼苗抗病酶活性影响的研究

采用平均分子量分别为3000、5000、10000的0.3%(w/v)壳寡糖溶液处理黑麦草种子并对处理过的种子进行发芽试验和幼苗抗病酶活性的测定。结果表明:三种不同分子量壳寡糖溶液处理黑麦草种子,均可以提高黑麦草种子的发芽率、发芽指数和活力指数,并且提高了幼苗的叶绿素、可溶性蛋白的含量。增强了幼苗的过氧化物酶(POD)活性,诱导了病程相关蛋白(即,几丁质酶和β-1,3-葡聚糖酶及苯丙氨酸解氨酶)的表达。其中,以平均分子量为10000的壳寡糖对种子活力及幼苗的生长和抗病酶活性的影响最好,其发芽指数和活力指数分别比对照提高了32.64%、60.47%;苗高、可溶性蛋白含量、苯丙氨酸解氨酶、几丁质酶和β-1,3-葡聚糖酶活性分别比对照提高了20.98%、33.80%、43.17%、15.73%、26.41%。     

甘露寡糖添加方式对哺乳期犊牛瘤胃细菌菌群结构的影响

为利用16S rDNA技术研究甘露寡糖不同添加方式对哺乳期犊牛瘤胃细菌菌群结构影响,本研究选用出生日龄一致、体重接近、健康状况良好的荷斯坦公犊牛20头,随机分为4组。CR组为对照组,饮用乳及开食料中均不添加甘露寡糖;ORa组在饮用乳中添加5 g甘露寡糖,开食料中不添加甘露寡糖;ORb组在开食料中添加5 g甘露寡糖,饮用乳中不添加甘露寡糖;ORc组在饮用乳及开食料中各添加2.5 g甘露寡糖(混合添加)。应用16S rDNA测序技术,研究了甘露寡糖添加方式对犊牛瘤胃细菌构建的影响。结果表明:甘露寡糖添加方式会影响哺乳期犊牛瘤胃细菌总数,但对哺乳期犊牛瘤胃细菌菌群多样性未产生显著影响(P> 0.05)。在门水平上,与对照组相比,ORb组颗粒料中添加甘露寡糖显著降低了厚壁菌门与放线菌门的丰度(P <0.05),极显著提高了变形菌门的丰度(P <0.01),优势菌门增加为3种,分别为拟杆菌门、厚壁菌门与变形菌门。在属水平上,甘露寡糖不同添加方式导致哺乳期犊牛瘤胃细菌菌群结发生了改变,其中甘露寡糖不同添加方式对小杆菌属和脱硫弧菌属在瘤胃内丰度均产生了影响,但对ORa组与ORc组犊...     

具有农业生物活性壳寡糖的研究进展

壳寡糖是一类由N-乙酰氨基葡萄糖或氨基葡萄糖通过β-(1,4)-糖苷键连接起来的低聚合度水溶性的糖类,在食品、医药、化妆品等方面具有广泛用途。主要评述了壳寡糖在植物生长调节(诱导抗性)、杀菌作用以及杀虫活性方面的应用,表明壳寡糖是一种对环境友好的、良好的生物源农药。     

氨基寡糖素对桃细菌性穿孔病的防治效果及增产作用研究

为明确氨基寡糖素5%水剂对桃细菌性穿孔病的防治效果和增产作用,特进行了相关试验调查研究。结果表明,在桃树上喷施氨基寡糖素5%水剂后,对桃树主要病害桃细菌性穿孔病的防效可达63%以上,与单独使用常规化学药剂防效基本相等,具有防病、抗病、减少化学农药使用,保护环境的效果;同时可提高果实外观品质,增产率在7%左右。可在桃树生产中大面积广泛使用。     

The Effect of Levels of α-Galactosidase Enzyme on Performance of Broilers Fed Diets Based on Corn and Soybean Meal

A study was conducted with male chicks of a commercial broiler strain to evaluate the effects of different dosage levels of a commercial α-galactosidase enzyme. Diets were formulated based on corn and soybean meal to meet the nutrient standards of top poultry companies. The positive control diet was formulated with no adjustment in the ME content of the soybean meal associated with enzyme supplementation. The negative control diet was formulated assuming a 10% improvement in the ME of the soybean meal. The negative control diet was supplemented with 0, 1.5, 3.0, 4.5, or 6.0 g of enzyme per kilogram of soybean meal to provide for 0, 45, 90, 135, or 180 galactosidase units (GALU)/kg of soybean meal. Each of the test diets was fed in mash form to 8 replicate pens of 30 birds. Body weight, feed efficiency, mortality, and calorie conversion were determined at 14, 35, and 42 d of age. Body weight, feed efficiency, and mortality were not significantly (P < 0.05) affected by dietary treatment. Birds fed the negative control with no enzyme supplement were numerically reduced in body weight or feed efficiency as compared with the control diet; however, addition of the enzyme was without benefit. When unadjusted energy values were analyzed, birds fed the negative control diet were more efficient in calorie conversion, but this finding was unrelated to enzyme addition, suggesting that diet composition was responsible for the differences in calorie utilization. When adjusted energy values were compared, birds fed the negative control tended to have higher (less efficient) calorie conversion than those fed the positive control with little or no indication of improvement from the addition of the α-galactosidase enzyme. Results of this study show no benefit from the addition of the enzyme used in this trial.     

双峰驼精清及其活性组分凝集素寡糖的初步研究

应用植物血凝素与寡糖结构相同或相似的糖复合物专一凝集的原理与方法,结合小鼠排卵试验,间接观察了公驼精清及其经ＤＥ－５２离子交换层析和高效液相层析提取分离的活性组分的蛋白组成。结果表明,公驼精清内糖蛋白含有２种以上的寡糖,其内的活性组分及诱导排卵因子与所试植物血凝素不发生反应     

壳寡糖诱导植物抗病毒病研究初报

以海洋壳寡糖中科6号为试材,对寡糖类化合物抗病毒性质和抗病毒机理进行了初步研究。室内生测结果表明,烟草用50μg/mL中科6号预防处理后24h再接种烟草花叶病毒(TMV),其对由TMV引起的烟草花叶病毒病的相对防效为84.73%,显著高于对照;KI-I染色法试验结果表明,预防处理烟草半叶上的淀粉斑平均为35个,明显少于对照;叶绿素测定结果表明,50μg/mL中科6号预防处理的烟草叶绿素含量达8.67μg/g,高于发病对照和病毒A预防处理组,低于空白对照。     

甘露寡糖对肠道健康和免疫的调控机制及其在畜禽生产中的应用

过去几十年来,由于饲用抗生素在畜牧养殖业中的滥用,导致畜禽正常的肠道菌群被破坏并引起肠道细菌耐药性和环境污染等一系列问题,严重损害了畜禽的肠道健康。同时,近年来集约化养殖已经成为畜牧业的发展方向,养殖规模越来越大,如何有效地提高畜禽免疫力已然成为重点的研究方向。健康的肠道是保障畜禽健康生长的基础,保持健康的肠道菌群,能有效提高动物机体的免疫力和抗病能力。甘露寡糖是一种绿色新型饲料添加剂,作为一类功能性寡糖,具有改善畜禽肠道健康和提高免疫应答等作用。在猪生产中,添加甘露寡糖能够提高断奶仔猪的生长性能和免疫力。在家禽生产中,添加甘露寡糖能够改善家禽肠道菌群并提高生产性能和肉品质。作者主要介绍了甘露寡糖的结构及理化性质、改善肠道健康和免疫调控机制及其在断奶仔猪、育肥猪、蛋鸡和肉鸡生产中的应用效果。重点总结了甘露寡糖对畜禽肠道健康和免疫的调控机制及免疫途径,旨在为甘露寡糖在肠道健康和免疫调控方面的深入研究及其在畜禽养殖中的应用提供理论依据。     

寡糖及其在饲料生产中的应用

本文综述了寡糖的概念、种类、作用机理及其在畜牧生产中的应用。结合当前人们逐渐增强的绿色环保意识，提出了开发天然饲料添加剂。     

Dietary administration of Bacillus (B. licheniformis and B. subtilis) and isomaltooligosaccharide influences the intestinal microflora,immunological parameters and resistance against Vibrio alginolyticus in shrimp,Penaeus japonicus (Decapoda: Penaeidae)

The experiment was conducted to investigate the effects of oral administration of probiotics (Bacillus licheniformis and Bacillus subtilis) in combination with prebiotic isomaltooligosaccharide (IMO) on the intestinal microflora and immunological parameters of Penaeus japonicus and its resistence against Vibrio alginolyticus. A basal diet was supplemented with 0% probiotics and prebiotic (control), 10⁸ colony forming unit (CFU) g^?1B. licheniformis and 0.2% IMO (T1), 10⁸ CFU g^?1B. subtilis and 0.2% IMO (T2), 10⁸ CFU g^?1B. licheniformis in combination with 10⁸ CFU g^?1B. subtilis and 0.2% IMO (T3). The results showed that the total bacterial counts significantly increased (P<0.05) and Vibrio counts significantly decreased (P<0.05) in the intestine of shrimp with supplementation of dietary synbiotics. Shrimp fed the diet with both Bacillus probiotics and IMO (T3) produced significantly higher immune parameters (phenoloxidase activity, lysozyme activity and nitric oxide synthase activity and superoxide dismutase activity) than the control group (P<0.05). Significant lower cumulative mortality after challenge with V. alginolyticus was also observed in shrimp fed diet with both Bacillus probiotics and IMO (T3) than that in the control group (P<0.05). The results indicated that the oral administration of probiotics (B. licheniformis and B. subtilis) and prebiotic IMO has positive effects on bacterial flora in P. japonicus gut, and can activate non‐specific immunity of shrimp.