代乳粉添加甘露寡糖对7—28日龄湖羊羔羊胃肠道发育的影响

【目的】探讨代乳粉中添加甘露寡糖（mannan oligosaccharides,MOS）对7—28日龄湖羊羔羊胃肠道生长发育的影响。【方法】选择同质性良好的7日龄湖羊公羔（双羔）30只,随机分为2组,每组15只,每只为1个重复,对照组羔羊饲喂不含MOS的代乳粉,试验组羔羊饲喂含0.2 % MOS的代乳粉,试验期21d。羔羊28日龄时,两个试验组各随机选择8只羔羊屠宰,取出消化道,称量各胃室和肠段包含内容物的质量和净质量,量取各肠段长度,用以计算各部位的相对质量和内容物分布,以及各肠段的相对长度。多聚甲醛固定皱胃胃底腺区及十二指肠、空肠和回肠中段的组织样品,测定组织形态和小肠上皮细胞凋亡率。采集十二指肠、空肠和回肠的黏膜样品,测定紧密连接蛋白1 (claudin 1)、闭锁小带1（zonula occludens-1,ZO-1）和闭锁蛋白（occludin）的mRNA表达量。【结果】除空肠相对长度外（%全肠长度,P=0.040）,MOS对羔羊胃肠指数（%活体质量）、胃肠相对质量（%全胃质量、%全肠质量和%全胃肠质量）、肠道相对长度（%全肠长度）、内容物相对活体质量（%活体质量）、胃肠内容物相对总胃/肠内容物及总胃肠内容物相对质量（%总胃内容物、总肠内容物、总胃肠内容物）、小肠上皮细胞凋亡率和小肠黏膜claudin 1蛋白mRNA的表达量均没有产生显著影响（P＞0.05）,但MOS显著提高羔羊十二指肠绒毛高度和肌层厚度并显著降低绒毛宽度（P=0.033,P=0.047,P=0.015）,显著上调空肠ZO-1蛋白mRNA表达量（P=0.028）,此外,MOS有提高羔羊回肠绒毛高度、绒毛宽度和隐窝深度、皱胃肌层厚度及回肠occludin蛋白mRNA表达量的趋势（P=0.075,P=0.078,P=0.085,P=0.084,P=0.052）。【结论】MOS对7—28日龄湖羊羔羊胃肠道相对质量、长度和内容物分布基本无显著影响,但可改善十二指肠和回肠绒毛及肌层的组织形态,维持小肠屏障功能,有利于提高养分消化率。     

Effects of Adding Mannan Oligosaccharides to Diets with Different Concentrate to Forage Ratios on Ruminal Fermentation of Sheep in vitro

The test was aimed at determining the effects of adding MOS to diets with different concentrate to forage ratios on ruminal fermentation of sheep in vitro.The 4×6 two-factor experimental design was chosen.There were 4 diets with different concentrate to forage ratios(20:80, 30:70, 40:60 and 50:50) and added to 6 dosages MOS(0, 0.4%, 0.8%, 1.2%, 1.6% and 2.0%), respectively.The method of gas production in vitro was used to measure the total gas and CH₄ production, IVDMD, IVCPD and IVOMD after cultured for 3, 6, 9, 12 and 24 h.The results showed that the gas(except 12 and 24 h) and CH₄ production(except 9 h) were not impacted by the two factors(P>0.05).The IVDMD, IVCPD and IVOMD were significantly affected by concentrate to forage ratios(P<0.05), while the IVCPD at 24 h was significantly affected by MOS(P<0.05).Meanwhile, all the indexes were not influenced by the interaction of two factors(P>0.05).The IVDMD and IVOMD increased with the rising of concentrate approximately, while the IVCPD decreased with the rising of MOS roughly.The biggest associative effect was gained in 30:70 concentrate to forage diet when adding 1.2% MOS.     

Effects of the prebiotic mannan‐oligosaccharide on feed deprived zebrafish: Growth and reproduction

This study was designed to investigate whether the prebiotic mannan‐oligosaccharides (MOS) can reduce the deleterious impacts of feed deprivation on growth and reproduction in zebrafish. In the growth performance experiment, juvenile fish were distributed in the following four treatments: normal‐control (NC), starved‐control (SC), normal‐prebiotic (NP) and starved‐prebiotic (SP). After 8 weeks, NP and SC fish showed the highest and lowest growth patterns, respectively among treatments. Standard length, specific growth rate and feed conversion ratio did not differ significantly between NC and SP treatments. Autochthonous lactic acid bacteria (LAB) were significantly higher in NP and SP than the NC and SP treatments. Feed restriction resulted in significantly lower concentrations of thyroxine. In the reproductive performance experiment, additional juveniles were fed as in the growth experiment. Crossing in the final week of the experiment resulted in successful spawning in only NP fish, which showed mature sperm and oocytes in histological examinations. The number of spermatozoa was significantly lower in the fish that experienced feed restriction; however, the oocytes of SP females were at the same maturation level to that observed in NC females. Sex‐steroids changed after both starvation and MOS supplementation where NC and SP showed no differences in the levels of testosterone and female's 17β‐estradiol. These results indicate that MOS supplemented diet reduced some side effects of feed deprivation (final weight and length, SGR, FCR and levels of LAB and T3), and suggest that supplementation of the diet with MOS may ameliorate some of the negative effects of feed deprivation in zebrafish.     

魔芋再制奶酪的研制

以天然切达奶酪和魔芋粉为主要原料,研究了魔芋再制奶酪的生产工艺,采用L9(34)正交试验法,分析了不同切达奶酪添加比例、魔芋粉的添加量、乳化盐添加量和乳化时间对魔芋再制奶酪色泽、滋气味和组织状态的影响,确定了生产魔芋再制奶酪的最佳工艺条件为:不同切达奶酪(3个月成熟∶9个月成熟)添加比例1∶3,质量分数6%的魔芋粉,质量分数2%的乳化盐,乳化时间6 min。由此制得的魔芋再制干酪,不仅可以保持传统再制干酪的组织状态,并且具有魔芋的滋气味。     

不同精粗比饲粮中添加甘露寡糖对绵羊瘤胃养分降解率的影响

本试验采用尼龙袋法研究不同精粗比饲粮中添加甘露寡糖(MOS)对绵羊瘤胃养分降解率的影响。选取6只安装永久瘤胃瘘管的羯羊(白萨福克×小尾寒羊♀),采用4×6双因子析因试验设计,共设饲粮精粗比和MOS添加水平2个因子,其中饲粮精粗比分别为20∶80(A1)、30∶70(A2)、40∶60(A3)和50∶50(A4),MOS添加水平分别为0(B1)、0.4%(B2)、0.8%(B3)、1.2%(B4)、1.6%(B5)和2.0%(B6)。结果显示:饲粮精粗比对不同时间点绵羊瘤胃干物质(DM)、有机物(OM)和粗蛋白质(CP)的降解率、降解参数[DM、OM:快速降解部分(a)、慢速降解部分(b)和可降解部分(a+b);CP:a、b和b的降解速率(c)]及有效降解率均产生了显著影响(P0.05),其变化规律均为随饲粮精料比例的升高而升高,在A4组达到最高;MOS添加水平仅对不同时间点绵羊瘤胃CP的降解率及降解参数a+b产生了显著影响(P0.05),其变化规律均为随MOS添加水平的增加先升高后降低,在B5组达到最高。饲粮精粗比和MOS添加水平对绵羊瘤胃养分降解率没有产生显著的交互作用(P0.05)。由此得出,饲粮精粗比为50∶50时绵羊瘤胃干物质、有机物和粗蛋白质的有效降解率最高,MOS添加水平达到1.6%时绵羊瘤胃粗蛋白质的降解率最高。     

β-甘露聚糖酶异源表达及甘露寡糖制备研究

以产β-甘露聚糖酶(MAN)的枯草芽孢杆菌HD145为目的菌株,PCR扩增MAN基因片段,克隆到p HBM905A载体并转化至毕赤酵母,重组子利用甲醇进行诱导。纯化的MAN酶解槐豆胶与瓜尔豆胶,质谱检测水解产物。SDS-PAGE结果表明,MAN基因实现了表达,摇瓶酶活性为3 200 U/m L,酶最适温度与pH分别为55℃与6.0,pH 4~7时稳定性较好,在40、50、60℃的半衰期分别为165、105、42 min,Zn~(2+)、Ag~+、Co~(2+)对酶活性存在一定的抑制。槐豆胶与瓜尔胶经MAN酶解后得到二糖至十糖的寡糖。     

Haematological modulation and growth of Labeo rohita fingerlings: effect of dietary mannan oligosaccharide,yeast extract,protein hydrolysate and chlorella

The present study was conducted for 60 days to delineate the efficacy of various dietary immunomodulators like mannan oligosaccharide (MOS), yeast extract (YE), protein hydrolysate (PH) and chlorella (CL) in Labeo rohita fingerlings. Five hundred and eighty‐five L. rohita fingerlings (average weight: 4.15 ± 0.07 g) were randomly distributed in 13 treatment groups with each of three replicates. Thirteen semi‐purified isonitrogenous (crude protein 324.7–332.5 g kg^?1) and isocaloric (17.66–17.80 MJ kg^?1) diets were prepared with three graded levels (1%, 2% or 4%) of immunostimulants, except the control. At the end of the feeding trial, weight gain%, specific growth rate, feed conversion ratio, leucocyte count, erythrocyte count, haemoglobin content, serum protein, globulin, albumin–globulin ratio, nitroblue tetrazolium (NBT) value and survival percentage were evaluated. Growth was significantly higher in the MOS‐fed group. All the immune parameters studied were also recorded higher in the MOS 1%‐supplemented group. The survival percentage after challenging with Aeromonas hydrophila was higher (P<0.05) in the MOS‐, YE‐ and PH‐fed groups and the lowest in the CL‐treated group. It can be concluded that dietary supplementation of MOS at a 1% dietary level promotes growth and survival in L. rohita fingerlings. In contrast, higher inclusion levels of immunostimulants led to an immunosuppressive effect in L. rohita fingerlings.     

魔芋甘露聚糖含量测定研究

研究了以葡萄糖为标准,以DNS为显色剂,用比色法原理间接测定魔芋精粉中甘露聚糖含量的方法,结果表明该方法简单、准确,适于不同等级魔芋精粉中甘露聚糖的测定。     

魔芋甘露聚糖热风干燥工艺研究

利用热风干燥装置,在风温50～80℃,风速0.5m/s,厚5～12.5mm,面积78.5cm2的条件下,研究了风温、厚度对魔芋甘露聚糖干燥特性和效率的影响,提出了魔芋甘露聚糖热风干燥工艺。     

啤酒酵母甘露聚糖的提取及其对鸡肠道微生物区系的影响

研究了甘露聚糖复合物的提取技术,确立了该复合物的制备工艺,分析了甘露聚糖的化学组成.结果表明,该复合物是含蛋白质的多糖,其蛋白质的氨基酸组成具有明显的特征性,苏氨酸和丝氨酸的含量较高,而蛋氨酸相对较少.在饲料中添加MOS饲喂雏鸡至第10日,可使粪便中的大肠杆菌数量显著降低(P＜0.05),而乳杆菌数量极显著提高(P＜0.01).