三丁酸甘油酯对乙酸刺激仔猪肠道屏障功能的影响

本试验旨在研究三丁酸甘油酯（TB）对乙酸（ACA）刺激仔猪小肠黏膜生长和肠道屏障功能的影响。试验选用18头体重接近、健康的28日龄断奶仔猪（杜×长×大）,随机分为3个处理：对照组、乙酸组和TB组,每个处理6个重复,每个重复1头猪。试验期为21 d。试验期内对照组和乙酸组饲喂基础日粮,TB组饲喂基础日粮+0.1% TB。于试验第15天清晨,乙酸组和TB组仔猪直肠灌注10 mL 10%乙酸,对照组直肠灌注相应剂量的灭菌生理盐水。于试验第18、21天清晨前腔静脉采血,测定血浆二胺氧化酶（DAO）活力;第21天屠宰取样,取空肠、回肠等组织样品,测定仔猪肠道形态结构、肠道黏膜损伤相关基因mRNA水平等指标。结果表明：①未用乙酸刺激前,与对照组相比,日粮中添加0.1% TB对仔猪平均日增重有一定程度提高（P=0.089）,且显著降低了仔猪料重比（P<0.05）;②与对照组相比,乙酸组显著降低了空肠黏膜绒毛高度、回肠黏膜绒毛高度与隐窝深度比值及空肠绒毛表面积（P<0.05）;③与乙酸组相比,TB组显著降低了血浆DAO活力（P<0.05）,极显著降低了回肠AREG基因的相对表达量（P<0.01）。综合上述结果,日粮中添加0.1% TB能缓解乙酸诱导的仔猪肠黏膜生长及肠道屏障功能的损伤。     

Screening of Probiotics Inhibiting E. coli K88 in vitro

The probiotics tested in the experiment were isolated from the intestinal of weaning piglets.The isolated probiotics and E.coli K88 were inoculated into the culture of intestinal porcine epithelial cell-1 (IPEC-1).The activity of lactate dehydrogenase (LDH) in the supernatant was measured after incubating for 2.5 h.At the same time, the probiotics and E.coli K88 were co-cultured in vitro, the number of E.coli K88 was counted and the probiotics which could be resistant to the E.coli K88 were selected 2.5 h later.The results showed that the Lactobacillus casei and Bacillus coagulans could significantly reduce LDH activity (P<0.05), decrease the damage of E.coli K88; Bacillus coagulans could inhibit the growth of E.coli K88.At the same time, Bacillus coagulans could resist high temperature, acid and bile salt.The results showed that Bacillus coagulans strains had great potential as the application of probiotics strains.The methods could be used as a model of screen probiotics which could inhibit the growth of E.coli K88 in vitro.     

Long-term Electrocardiography Recording with Holter Monitoring in 15 Donkeys

The heart rates (HR) and rhythms of 15 healthy donkeys of various ages, both sexes, and various breeds were analyzed throughout 24-hour Holter monitoring. The animals were evaluated at rest in their daily environment without the presence of investigators causing stress, using a three-channel digital Holter recorder. Analysis revealed a maximal HR range from 62.5 to 93.7 beats/min (mean, 72.50 ± 7.51 beats/min), whereas the minimal HR ranged from 29.7 to 42.2 beats/min (mean, 34.90 ± 4.22 beats/min). The daily mean HR was 47.55 ± 3.70 beats/min. The daytime mean HR was 49.39 ± 2.77 beats/min, whereas the night time rate was 46.22 ± 4.38 beats/min. Sinus bradycardia and sinus tachycardia were detected in 7 and 10 of 15 studied donkeys, respectively. Cardiac dysrhythmias due to high vagal tone such as sinoatrial heart block and second-degree atrioventricular heart block were occasionally recorded in 1 and 3 donkeys, respectively. A higher mean HR and fewer cardiac dysrhythmias were observed in donkeys than in horses and ponies at rest. These findings could be justified by differences in the autonomic nervous system tone.     

转AtNHX1基因马铃薯田间盐胁迫下的生理反应及耐盐性的综合评价

以转AtNHX1基因的8个马铃薯株系(1、2、4、6、8、15、18、19)和未转基因的"甘农薯2号"(CK)为材料,在正常地以及全盐含量分别为0.56%、0.29%的高盐和中盐地上种植,分析其生长和生理指标的变化,通过隶属函数法、相关分析和聚类分析等方法综合评价耐盐性。结果表明:随着盐浓度的增加,转基因株系的株高、叶面积扩展率、单株产量、叶绿素的含量、超氧化物歧化酶(SOD)活性以及脯氨酸含量的上升幅度均高于对照植株(为对照的1.17~3.96倍)。而丙二醛(MDA)、相对电导率显著低于对照植株,为对照的63.07%~78.4%和82.7%~86.35%。根据生长和生理指标综合评价各株系的耐盐性,筛选出1个强耐盐株系和3个较强耐盐株系,各株系耐盐性由强至弱为:19158418216CK,AtNHX1的导入显著提高了大田马铃薯植株的耐盐性,利用耐盐性综合评价方法有助于耐盐株系的筛选。     

玉米黄花叶病毒运动蛋白的原核表达纯化与抗血清制备

为实现对玉米黄花叶病毒（maize yellow mosaic virus,MaYMV）的血清学检测,丰富该病毒的检测方法,将编码MaYMV运动蛋白（movement protein,MP）的基因连接到原核表达载体pDBHis-MBP上,将构建成功的原核表达质粒转化到大肠杆菌Escherichia coli中诱导表达融合蛋白,将纯化后的融合蛋白对新西兰大白兔Oryctolagus cuniculus进行免疫并制备MaYMV MP多克隆抗血清,并采用Western blot对抗血清的效价、灵敏度和特异性进行检测。结果显示,利用成功构建的原核表达载体经诱导表达获得分子量大小约为62 kD的融合蛋白,纯化后对新西兰大白兔进行免疫获得MaYMV MP抗血清,该抗血清的效价为1∶128 000,灵敏度为1∶32,且该抗血清能够特异性地检测到本氏烟Nicotiana benthamiana中瞬时表达的MaYMV MP,而不与马铃薯卷叶病毒属Polerovirus及黄症病毒属Luteovirus的其他病毒发生血清学交叉反应,证明该抗血清具有良好的特异性。表明本研究制备的MaYMV MP抗血清能特异性...     

鸡Toll样受体在IBDV免疫中的作用研究

为了揭示鸡先天性免疫反应在IBDV疫苗过程中的作用,将40只14日海兰褐蛋鸡随机分成两组,实验组接种IBDV活疫苗,对照组注射生理盐水,隔离饲养。于免疫前和免疫后12h、24h、48h、72h、130h各取脾脏和法氏囊分离淋巴细胞并提取总RNA,用实时荧光定量检测方法检测各组中chTLR3、chTLR7、chTLR21表达的动态变化。结果显示,在免疫后36h,鸡法氏囊和脾脏中chTLR3表达变化最显著,在免疫后48h,鸡脾脏和法氏囊中chTLR21表达变化也较为明显。提示chTLR3在鸡对IBDV的免疫应答中起主要作用。     

A Droplet Digital PCR Method for Detection of Newcastle Disease Virus

This experiment was conducted to establish a droplet digital PCR (ddPCR) method for the detection of Newcastle disease virus (NDV). A ddPCR method was developed, which the primers and probes were designed based on the conservative regions of F gene of NDV. The concentration of primer and probe, the annealing temperature in ddPCR reaction were optimized. The sensitivity, specificity and reproducibility of ddPCR method were evaluated. In results, the optimal primer concentration and the probe concentration were 900 and 250 nmol·L^-1, the optimum annealing temperature was 55℃. The detection limit of ddPCR method was 1.8 copies·μL^-1 with a good linear response, it had no cross reaction with other six viruses (include IBV), the coefficient of variation of sample repetition was 2.4%. All the results showed that NDV ddPCR was sensitive and specific, it was suitable for quantitative detection of clinical samples infected with NDV.     

山东规模化养殖场毛皮动物多重感染病原学分析

2012—2013年间,山东10个地市多家毛皮动物养殖场养殖的毛皮动物（狐狸、貉子、水貂）出现腹泻,皮肤湿疹,神经症状,空怀、流产、出血性肺炎等症状和病变类似的疫情,为探明其病因,本研究对发病规模化毛皮动物养殖场发病情况进行调查,并对送检的病料进行病原学检查,结果发现,犬瘟热病毒、细小病毒、阿留申病毒感染率分别为54.21%、47.30%、31.35%;肺炎克雷伯菌、奇异变形杆菌、肺炎双球菌、大肠杆菌、沙门杆菌、绿脓杆菌、加德纳菌的感染率分别为37.58%、25.05%、21.81%、14.04%、12.53%、10.37%、8.21%;犬瘟热病毒、细小病毒、阿留申病毒、肺炎克雷伯菌、奇异变形杆菌、肺炎双球菌6种病原的单独感染、二重感染、三重感染、四重感染分别为22.03%、39.52%、36.07%、2.38%,未见五重以上的感染。结果表明,近两年造成山东规模化场毛皮动物发病主要原因是由犬瘟热病毒、细小病毒、阿留申病毒与肺炎克雷伯菌、奇异变形杆菌、肺炎双球菌多重感染所致,这为规模化毛皮动物养殖场有效地控制疫病提供了理论依据。