酒糟和醋糟营养成分差异及其瘤胃降解特性分析

本试验旨在评价酒糟、醋糟等非常规饲料资源的饲用价值,为酒糟醋糟资源应用于肉牛养殖提供数据参考.试验选用山西不同地区酒糟、醋糟试样5个,试样编号分别为白酒糟、啤酒糟、醋糟1、醋糟2、醋糟3,发酵原料分别为白酒糟(高粱)、啤酒糟(大麦+大米)、醋糟1(高粱+大麦)、醋糟2(大麦+玉米)、醋糟3(高粱+玉米).通过实验室常规...     

丁酸钠对断奶仔猪生长性能及免疫功能的影响

本试验旨在研究丁酸钠对断奶仔猪生长性能及免疫功能的影响。试验选用162头28日龄(8.25±0.18)kg断奶去势仔猪,随机分为6组,每组3个重复,每个重复9头猪。对照组饲喂基础饲粮,试验组分别在基础饲粮中添加0.01%抗生素(Ⅰ组)、0.10%丁酸钠(Ⅱ组)、0.10%丁酸钠+0.01%抗生素(Ⅲ组)、0.30%氧化锌+0.01%抗生素(Ⅳ组)和0.10%丁酸钠+0.30%氧化锌+0.01%抗生素(Ⅴ组)。试验期21 d。结果表明:1)Ⅲ、Ⅳ、Ⅴ组末重、平均日采食量和平均日增重显著高于对照组(P<0.05)。2)除Ⅰ组外,其他4个试验组的脾脏指数、胰脏指数、淋巴结指数均显著高于对照组(P<0.05);与对照组相比,各试验组免疫球蛋白G含量均显著升高(P<0.05),各试验组肠道黏膜免疫球蛋白A阳性(IgA+)细胞含量均有所上升,其中Ⅲ组上升最显著。3)Ⅲ、Ⅴ组的二胺氧化酶活性分别比对照组降低了46.22%和44.83%(P<0.05);Ⅲ、Ⅳ、Ⅴ组的皮质醇含量分别比对照组降低了43.13%、43.14%、47.01%(P<0.05)。结果提示,饲粮中添加丁酸钠能促进断奶仔猪生长和免疫器官发育,提高血清免疫球蛋白含量,刺激机体肠道黏膜分泌免疫球蛋白A阳性细胞,提高其免疫功能。此外,丁酸钠与抗生素一起使用对促进生长性能和降低腹泻率作用效果更明显。     

江苏盐城首次记录到彩鹮

2020年5月4日在江苏盐城大丰麋鹿国家级自然保护区(120°47′—120°53′E,32°59′—33°03′N)记录到3只彩鹮。栖息地为一处浅滩水塘,3只彩鹮于水中觅食。以往曾宣布彩鹮在国内绝迹,本次记录填补了彩鹮在本地区的分布空白,证实了彩鹮在江苏省仍有分布。这一纪录或许说明本地区栖息地得到了有效的改善。     

Effect of follistatin on pre‐implantational development of pig parthenogenetic embryos

The present study was designed to explore effects of follistatin (FST) on pre‐implantational development of parthenogenetically activated embryos (PAEs) in pigs. First, we investigated the FST messenger RNA expression level and dynamic FST protein expression patterns in porcine oocytes and PAEs. Then, PAEs were placed in embryo culture medium supplemented with 10 ng/mL of FST‐288, FST‐300, and FST‐315. Next, PAEs were cultured with 0, 1, 10 and 100 ng/mL of FST‐315 protein throughout the in vitro culture (IVC) duration. Further, 10 ng/mL of FST‐300 was added from the start of IVC in which PAEs were treated for 30, 48 and 60 h. The results showed that 1 ng/mL FST‐315 could significantly increase the total cell numbers of blastocyst and trophectoderm cell number in PAEs. Exogenous FST‐300 supplementation could significantly promote the early cleavage divisions and improve the blastocyst formation rate of porcine embryos. FST‐300 appeared to affect early embryonic development before activation of the embryonic genome. In all, the study confirmed for the first time that FST plays a role in promoting early embryonic development in pigs, which differed with different FST subtypes. FST‐300 could facilitate the initial cleavage time and improve the blastocyst formation rate, and FST‐315 could improve the blastocyst quality.     

套筒式橡胶减振器的疲劳工况试验研究

为了准确掌握金穗4SW系列马铃薯挖掘机摆动分离筛新型套筒式橡胶减振器的疲劳工况，进行了田间试验和实验室试验。试验表明，该橡胶减振器能够满足生产实际要求和对橡胶减振器的设计寿命要求。给出了符合橡胶减振器疲劳损失衡量标准的静刚度损失值，经生产实践证明，此值具有指导生产的实际意义。     

南海柘林湾鱼类群落结构季节变动的研究

基于2013年2月(冬季)、5月(春季)、8月(夏季)和11月(秋季)柘林湾拖网调查数据,分析了柘林湾甲壳类资源密度、种类组成和优势种、多样性的变化特征,并对甲壳类群落结构和环境因子的关系进行了研究。调查结果表明,甲壳类资源密度变化范围为30.094~199.048 kg·km^–2;甲壳类出现53种,隶属于2目13科22属,主要优势种为口虾蛄(Oratosquilla oratoria)、宽突赤虾(Metapenaeopsis palmensis)、锈斑蟳 (Charybdis feriatus)和哈氏仿对虾(Parapenaeopsis hardwickii)等;多样性指数变化范围为2.31~3.03,均匀度指数变化范围为0.55~0.8,物种丰富度指数变化范围为1.55~3.29。单因子相似性分析(ANOSIM)、聚类分析和非度量多维标度分析(NMDS)结果表明,柘林湾海域甲壳类群落结构存在明显的季节更替。相似性百分比分析(SIMPER)表明各季节典型种主要有口虾蛄、断脊口虾蛄(O.interrupa)等,分歧种主要有口虾蛄、红星梭子蟹(Portunus sanguinolentus)等。典范对应性分析表明,影响柘林湾海域甲壳类群落结构季节变化的主要环境因子依次为水温、pH和溶解氧。     

Polyaniline-Modified Quartz Crystal Microbalance Sensor for Detection of Formic Acid Gas

A polyaniline-modified quartz crystal microbalance (QCM) sensor was obtained through immobilizing the polyaniline film on the silver electrode surface of quartz crystal resonator by an electrochemical method. The sensor was studied for detecting the formic acid gas of different concentrations, and the results showed that the resonant frequency of QCM decreased quickly in the beginning and tended to be constant in the end when exposed to formic acid gas. The frequency shifts decreased faster as the concentration of formic acid gas increased. And the frequency shifts of the QCM sensors were found to be linearly related to the concentration of formic acid gas, which might be used to estimate the concentration level of the formic acid gas within the range of experimental concentrations. The result of on-line monitoring test fully indicated that the QCM sensor responded effectively to the increasing concentration of formic acid and had important practical significance and broad application prospect in real-time detection of antique conservation environment in the museum.     

钳夹式棉花膜上精量穴播器的实验研究

将钳子夹持事物的思想运用到传统的滚筒穴播器取种装置的设计中,并将其运用到穴播器取种、清种和排种等播种过程,研制出新型棉花精量膜上穴播装置.为此,首先介绍了钳夹式棉花膜上精量穴播器关键部件的结构及工作过程,然后依靠实验的方法确定了钳夹式精量穴播器的影响因素,确定了该穴播器的各因素工作水平的最佳组合,实验结果对该穴播器的大田运用及推广具有一定的指导意义.     

快速检测大豆疫霉菌的酶联免疫技术研究

 大豆疫霉菌是我国的一类检疫性病菌,由于常规的检测方法速度慢,效率低,所以选择酶联免疫技术进行快速检测非常重要。     

毛泽东与江泽民民族经济发展思想比较与思考

从民族经济地位、发展战略思想和措施等方面对毛泽东与江泽民的民族经济发展思想进行比照,认为建国后,我国三代领导集体有关民族经济发展的思路,是我国民族经济发展和和谐社会构建的原动力。