鹅副粘病毒的人工感染试验

鹅副粘病毒是最新发现的,能引起各种年龄鹅发病的并致死的一种病毒。我们通过ＳＰＦ鸡胚分离的病毒尿囊液第４代,对鹅进行人工感染试验。结果表明,人工感染后,成年鹅群的发病率达到１００％,死亡率达３０％,１５日龄雏鹅感染后发病率和死亡率均达到１００％,这与自然发病鹅群的发病率和死亡率基本相同,而且人工感染后不管成年鹅还是雏鹅其临床病状和病理变化均与自然发病的鹅的病理变化相同,从而证实了该病理分离株的致病性及病原性。     

现代化战争中的媒体角色——伊拉克战争中美国媒体给我们的启示

有人说战争是媒体的狂欢节，而美国媒体向来是擅长同战争“共舞”的。在伊拉克战争中美国媒体就发挥了重要作用，成为战争的一个组成部分。如今，媒体对现代化战争所起的作用越来越重要，如何在战争中充分发挥媒体的作用，值得我们认真思考。美国媒体在伊拉克战争中，扮演着一个全新的角色，这为如何在现代战争巾运用媒体留下了宝贵的经验，带给我们重要启示。     

吐温-80对液氮冷冻处理的双歧杆菌的冻伤保护

向双歧杆菌培养基中添加吐温-80，可增加双歧杆菌的细胞膜柔韧性和弹性。经液氮冷冻处理24h后，测定双歧杆菌细胞漏出液中乳酸脱氢酶的活力，结果表明添加吐温-80，可显著降低细胞培养液中的乳酸脱氢酶的漏出率（p〈0．05），其中以添加0．025％吐温-80的效果尤为明显。     

盐城地区奶牛结核病和布鲁氏菌病检测及分析

奶牛结核病和布鲁氏菌病（以下简称“两病”）是农业部规定的二类动物疫病，都是人畜共患的慢性传染病，分别由结核分枝杆菌和布鲁氏菌引起。“两病”可引起肉、奶等畜产品质量、产量下降。使免疫力、繁殖力降低，严重影响养牛业发展。“两病”还可感染人，危害人体健康．给国家和人民群众带来巨大损失。     

Estimation of the ideal ratio of true ileal digestible sulfur amino acids:lysine in 8- to 26-kg nursery pigs

Four experiments were conducted to determine the ideal ratio of true ileal digestible (TID) sulfur AA to Lys (SAA:LYS) in nursery pigs at two different BW ranges using both DL-Met and 2-hydroxy-4-(methylthio)-butanoic acid (HMTBA) as Met sources. In Exp. 1, 1,549 nursery pigs (Triumph 4 x PIC Camborough 22; initial BW 8.3 +/- 0.08 kg) were allotted to one of nine dietary treatments. The basal diet (Diet 1) was a semicomplex corn-soybean meal-based diet (1.32% TID Lys) with no supplemental HMTBA or DL-Met (47.7% TID SAA:LYS). Diets 2 to 9 consisted of the basal diet supplemented with four equimolar levels of DL-Met or HMTBA (52.7, 57.7, 62.7, and 67.7% TID SAA:LYS). In Exp. 2, 330 nursery pigs (Triumph 4 x PIC Camborough 22; initial BW 11.4 +/- 0.10 kg) were allotted to one of nine dietary treatments. The basal diet (Diet 1) was a corn-soybean meal-based diet (1.15% TID Lys) with no supplemental HMTBA or DL-Met (49% TID SAA:LYS). Diets 2 to 9 consisted of the basal diet supplemented with four equimolar levels of DL-Met or HMTBA (54, 59, 64, and 69% TID SAA:LYS). In Exp. 3, 1,544 nursery pigs (Triumph 4 x PIC Camborough 22; initial BW 12.4 +/- 0.13 kg) were allotted to one of nine dietary treatments as in Exp. 2. In Exp. 4, 343 nursery pigs (Genetiporc; initial BW 12.8 +/- 0.56 kg) were allotted to one of six dietary treatments. The basal diet (Diet 1) was a corn-soybean meal-based diet (1.05% TID Lys) with no supplemental DL-Met (49% TID SAA:LYS). Diets 2 to 5 consisted of the basal diet supplemented with four levels of DL-Met (54, 59, 64, and 69% TID SAA:LYS), and Diet 6 was the basal diet supplemented with one equimolar level of HMTBA to satisfy 59% TID SAA:LYS ratio. In all experiments, increasing the TID SAA:LYS ratio resulted in quadratic improvements in ADG (P < or = 0.09) and G:F (P < or = 0.05). Three different methods were used to estimate the optimal TID SAA:LYS ratio for each experiment. The two-slope broken-line regression model, x-intercept value of the broken-line and quadratic curve, and 95% of upper asymptote across the four experiments indicated that the average optimal TID SAA:LYS ratios were 59.3, 60.1, and 57.7% for ADG and 60.6, 61.7, and 60.1% for G:F, respectively. Thus, the optimal TID SAA:LYS ratio for 8- to 26-kg pigs based on the average value of these three estimates was 59.0% for ADG and 60.8% for G:F.     

当代大学生就业中道德缺失问题的思考

大学生就业难是社会普遍关注的焦点问题之一。大学生就业中的伦理道德缺失不容忽视。要解决这一问题，除学校加强道德教育、企业提升自身魅力外，根本在于大学生自身的觉悟与个人素养的提高。     

不同小黑麦品种的种子产量及产量构成因素比较

以32份小黑麦品种为试验材料,研究了各品种的产量构成因素（穗长、小穗数,穗粒数、穗粒质量）以及他们之间的相关性。结果表明,小黑麦品种OH2276株高最高,为136．77cm,但其种子产量低;安新麦83—25的综合性状最优,穗粒数最多,为J09。19;北联4号,89D-8和DH796综合性状也较好,具有良好的应用前景;HB200上的综合性状最差,HB200下和OB74的综合性状较差。     

夏季奶牛乳房炎的综合防治措施

奶牛乳房炎是危害奶牛生产的一项重大疾病,是奶牛生产中的常见病和多发病,尤其在夏季发病率很高。笔者通过查阅大量文献资料和总结自身实践经验,对夏季奶牛乳房炎的有效防治进行综述,以供同行参考。     

新牧1号苜蓿两个抗逆相关基因启动子的克隆及分析

采用实时荧光定量PCR分析了新牧1号苜蓿（Medicago varia Xinmu 1）MvNHX1和MvDREB1基因在盐胁迫下的表达情况。此外,根据已获得的MvDREB1和MvNHX1基因序列设计特异引物,并以新牧1号苜蓿的基因组DNA为模板,克隆得到了这两个基因的启动子。利用生物信息学方法,分析这两个基因启动子的类型和结构,结果表明,MvNHX1和MvDREB1基因的启动子序列中均含有通用启动元件和上游调控元件,如CAAT框、TATA框、光响应元件、低温响应元件等,但部分响应元件的种类和数量不同。通过对两个基因启动子的克隆、分析及比较为进一步研究这两个基因的表达调控机制奠定了基础。     

禽胰多肽研究进展

禽胰多肽(avian pancreatic polypeptide,APP)是由36个氨基酸残基组成,由胰脏胰多肽细胞分泌的一种多肽。研究表明,APP具有促进畜禽采食,加快生长发育,调节胃肠道运动,影响内分泌活动和保护细胞膜的完整性等多种生理作用。在近30年的研究工作中,人们对胰多肽的生理功能和临床应用有了一定的了解,但是对其生理活性及作用机制的研究尚处于探索阶段,在许多方面还有待进一步研究揭示。