半固体人工饲料饲养日本通草蛉幼虫对荻草谷网蚜捕食作用

为评价一种半固体人工饲料饲养的日本通草蛉幼虫的捕食潜力,在室内研究了1~3龄幼虫对荻草谷网蚜的捕食作用和种内干扰作用。结果表明,1~3龄幼虫的捕食量随着猎物密度的增加而上升,当猎物密度增加到一定水平,捕食量趋向稳定,捕食功能反应曲线均符合Holling Ⅱ型方程。不同龄期幼虫对荻草谷网蚜理论最大日捕食量分别为42、179、204头。2龄幼虫的干扰效应用Hassell &Varley的模式(E=QP^-m)进行模拟,模拟模型为E=0.5074P^-0.6627,结果说明随着2龄幼虫密度的增大,其捕食作用率随之减小。     

湖南省洞口县第二例牛尿素中毒诊治报告

1前言湖南省洞口县第二例牛尿素中毒,制做了简易竹洞针,进行左赚部套洞针(竹洞针)穿刺术放气,灌入食醋,葡萄糖输液等抢救和治疗方案。牛场存栏328头,239头中毒,发病率72.9%,治疗239头,治愈216头,治愈率90.4%,较首例牛尿素中毒病例治愈率100%,降低9.6个百分点,瘤胃膨气病病牛128头,治愈105头,治愈率82.0%,较洞口县首例牛尿素中毒病例治愈率100%,下降18.0个百分点;并对牛瘤胃膨气病最佳抢救时间和尿素养牛正确用量用法进行了探索,供同行参考。     

内蒙古河套灌区节水灌溉工程实施后地下水变化的BP模型预测

根据黄河河套灌区多年的水文、气象和地下水资料，应用不同的ANN—BP网络模型对灌区年、月地下水埋深的变化进行了模拟，预测了黄河河套灌区节水工程实施后未来灌区年平均地下水位下降的情况，从预测结果可以看出，河套灌区节水工程实施后灌区平均地下水位预计下降0.5 m左右。此外对BP模型的结构设计中隐含层数、隐含单元数和学习速率的合理确定作了具体分析，提出了学习速率取值范围lr=0.01～0.1，为河套灌区节水工程改造规划、设计和管理决策及BP模型的应用提供了参考依据。     

基于FLANN数据融合的木材含水率检测方法

针对木材含水率的检测精度受到多种环境因子(温度、平衡含水率、风速等)的影响,提出了一种基于函数联接型神经网络FLANN的数据融合方法以消除环境温度对木材含水率检测精度的扰动。FLANN能利用函数扩展替代多层感知器(MLP)的隐含层,将输入信号空间维度下的线性不可分类的问题,扩展至较高信号空间维度的超平面上,简化了MLP的架构。与MLP相比,FLANN具有结构简单、收敛速度快和计算量小的特点。仿真结果及实验验证表明:基于FLANN的数据融合方法,能有效消除环境因子的扰动,并可实现木材含水率的稳定、实时、高精度检测。     

Amino acid profiles of rumen undegradable protein: a comparison between forages including cereal straws and alfalfa and their respective total mixed rations

Optimizing the amino acid (AA) profile of rumen undegradable protein (RUP) can positively affect the amount of milk protein. This study was conducted to improve knowledge regarding the AA profile of rumen undegradable protein from corn stover, rice straw and alfalfa hay as well as the total mixed ratio diets (TMR) based on one of them as forage source [forage‐to‐concentrate ratio of 45:55 (30% of corn stover (CS), 30% of rice straw (RS), 23% of alfalfa hay (AH) and dry matter basis)]. The other ingredients in the three TMR diets were similar. The RUP of all the forages and diets was estimated by incubation for 16 hr in the rumen of three ruminally cannulated lactating cows. All residues were corrected for microbial colonization, which was necessary in determining the AA composition of RUP from feed samples using in situ method. Compared with their original AA composition, the AA pattern of forages and forage‐based diets changed drastically after rumen exposure. In addition, the extent of ruminal degradation of analysed AA was not constant among the forages. The greatest individual AA degradability of alfalfa hay and corn stover was Pro, but was His of rice straw. A remarkable difference was observed between microbial attachment corrected and uncorrected AA profiles of RUP, except for alfalfa hay and His in the three forages and TMR diets. The ruminal AA degradability of cereal straws was altered compared with alfalfa hay but not for the TMR diets. In summary, the AA composition of forages and TMR‐based diets changed significantly after ruminal exposure, indicating that the original AA profiles of the feed cannot represent its AA composition of RUP. The AA profile of RUP and ruminal AA degradability for corn stover and rice straw contributed to missing information in the field.     

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...     

4种日粮条件下30～150日龄羔羊瘤胃消化代谢功能的变化

将16只30日龄体重约6～10kg装有瘤胃瘘管的罗姆尼与新疆美利奴羊杂交公羔分为4组，分别喂以不同消化能（DE，MJ／kg）和蛋白质（CP，％）水平的日粮（DE／CP：11．91／20、11．91／14、8．15／20和8．15／14），以15d为一研究时间段，每时间段的第9、10和11天在第一次喂料后的第0、1、3、6和9h采取瘤胃液样品，以研究30～150日龄期间羔羊瘤胃消化代谢的变化规律。结果表明，羔羊瘤胃液pH、氨态氮、丙酸、乙＋丙＋丁酸浓度随日龄而不断升高，在100日龄时趋于稳定，并且受日粮营养水平的影响。乙酸浓度的变化虽也受日龄和日粮营养水平的影响，但相对较小。羔羊瘤胃液体积在120日内几乎增加了15倍，并且也受日粮营养水平的影响。研究表明瘤胃消化代谢的发育是渐进性的，在100日龄时各项指标均趋于稳定，并且瘤胃液体积的增大对于瘤胃消化代谢能力的发育起着首要的作用。     

农田野花带群落构建及其稳定性特征

为维持农田野花带稳定性和持久性,以充分发挥其生态系统服务功能并扩大其应用范围,对8个不同建植年限(2、4和6年)的农田野花带混播群落的建立过程,包括群落密度、物种多样性指数以及不同寿命的初始植物和侵入植物重要值的变化规律进行了调查和分析.结果表明:1)播种建立的农田野花带群落,存在2次植物消亡,分别是一二年生植物和短命...     

Transgenic Rice Plants Harboring Genomic DNA from Zizania latifolia Confer Bacterial Blight Resistance

Based on the sequence of a resistance gene analog FZ14 derived from Zizania latifolia (Griseb.), a pair of specific PCR primers FZ14P1 /FZ14P2 was designed to isolate candidate disease resistance gene. The pooled-PCR approach was adopted using the primer pair to screen a genomic transformation-competent artificial chromosome (TAC) library derived from Z. latifolia. A positive TAC clone (ZR1) was obtained and confirmed by sequence analysis. The results indicated that ZR1 consisted of conserved motifs similar to P-loop (kinase 1a), kinase 2, kinase 3a and GLPL (Gly-Leu-Pro-Leu), suggesting that it could be a portion of NBS-LRR type of resistance gene. Using Agrobacterium-mediated transformation of Nipponbare mature embryo, a total of 48 independent transgenic T0 plants were obtained. Among them, 36 plants were highly resistant to the virulent bacterial blight strain PXO71. The results indicate that ZR1 contains at least one functional bacterial blight resistance gene.     

异齿裂腹鱼人工规模化繁殖技术研究

2010年4～6月,对野生异齿裂腹鱼(Schizothorax o' connori)人工规模化繁殖技术进行研究,并初步进行产后亲鱼恢复培养技术研究.对108尾雌鱼进行干法人工授精,共采卵104万多粒,孵出仔鱼62万多尾.其中45尾雌亲鱼自然成熟,共采卵46.8万多粒,平均受精率和孵化率低于人工催产雌鱼卵.人工催产83...