防御素调控动物肠道稳态的研究进展

随着抗生素在饲料产业中的全面禁用,如何在后抗生素时代中保证动物的高效生产成为当前饲料行业的主要任务。防御素作为一类重要的免疫调节分子,是机体防御体系的重要组成部分。越来越多的证据表明,防御素参与并调控动物肠道的微生态平衡,而后者常被认为是决定高效生产中饲料养分沉积与转化的关键。因此,全面了解防御素的作用机制及其参与动物肠道稳态调节的作用显得尤为重要。文章介绍了防御素的来源、功能及作用机制,并着重分析防御素在增强肠道屏障功能、促进肠道黏膜免疫反应以及调控肠道微生物菌群的作用,以期为防御素在动物生产中的应用提供理论指导和依据。     

鸡传染性贫血病毒vp3基因在真核细胞中的表达与功能分析

为研究鸡传染性贫血病毒(CIAV)VP3蛋白在宿主细胞中的作用,本研究采用PCR技术从CIAV DNA中扩增出vp3基因,并将该基因克隆到p MD18-T simple vector中。经测序证实所克隆的vp3基因与CIAV CUX-1标准株相同。并将vp3基因亚克隆到真核表达载体p EGFP-N1中,构建了重组真核表达质粒p EGFP-vp3与p CMV-Myc vp3,转染BHK-21和293 T细胞,经RT-PCR、荧光显微镜以及Western Blot证实转染的真核细胞能够表达VP3蛋白。以台盼蓝染色法检测细胞死亡,结果表明,VP3蛋白具有较强诱导细胞死亡的作用。该结果为深入研究CIAV的致病机理奠定了基础。     

氟苯尼考注射液中非法添加多西环素检查方法的建立

为建立氟苯尼考注射液中非法添加多西环素高效液相检查方法,研究使用C18(4.6 mm×150 mm,5μm)色谱柱,以醋酸盐缓冲液[0.25 mol/L醋酸铵溶液-0.1 mol/L乙二胺四醋酸二钠-三乙胺(100∶10∶1),调节p H值至8.8]-乙腈(85∶15)为流动相,采用二极管阵列检测器,波长采集范围为200~400 nm,记录色谱图波长为269 nm,流速为1 m L/min,进样量为10μL。结果表明,多西环素进样浓度在0.015~0.96 mg/m L范围内与峰面积呈良好的线性关系(r=1.0000);平均回收率为99.4%(n=9),RSD为0.3%。本方法简便、准确、可行,适用于氟苯尼考注射液中非法添加多西环素的检测。     

母牛黄体期的生理特点

<正>母牛排卵后,膜细胞和颗粒细胞间的基膜裂解,继而无血管的颗粒细胞层被含有膜细胞和血管的结缔组织所代替,颗粒细胞和膜细胞分化形成黄体细胞,产生孕酮、雌激素、催产素和松弛素,即为黄体期。血管进一步分支,从而为成熟黄体的代谢供给足够的血量。组成黄体的细胞中,内皮细胞占一半以上,且在黄体溶解过程中发挥关键的作用。对母牛而言,使卵泡黄体化的激素主要是促黄体素(LH)。正常条件下,黄体在LH存在下维持     

新疆肉用绵羊颗粒细胞抑制素βA基因RNAi载体的构建及其干扰效率验证

抑制素βA基因(inhibin-βA,INHβA)的表达与绵羊(Ovis aries)的产羔数有一定关系。为了观察INHβA对绵羊发情性状的影响以及在目的基因沉默后,引起的发情性状相关激素变化的情况,本研究利用RNAi技术构建载体干扰INHβA的表达。根据GenBank上绵羊INHβA(GenBank:NW_004080167.1)mRNA的序列设计干扰片段,通过酶切和测序验证,成功构建了4个INHβA基因RNAi质粒载体PLLU2G-shINHβA-1(I-1)、PLLU2G-shINHβA-2(I-2)、PLLU2G-shINHβA-3(I-3)、PLLU2G-shINHβA-4(I-4)和1个空载体(赛亚公司的PLLU2G)阴性对照;在成功分离卵巢颗粒细胞并建立培养体系后,利用Lip2000介导干扰载体转染细胞,通过荧光定量RT-PCR检测干扰前后INHβA的表达量。结果显示,4个干扰载体的干扰效率依次为34%,58%,39%,19%,其中I-2对INHβA表达的沉默效果最好。通过卵巢注射干扰载体I-2,检测干扰后绵羊血清INHβA、卵泡刺激素(FSH)、黄体生成素(LH)和雌二酮(E2)的含量。结果显示,注射干扰载体后INHβA和FSH分别呈现明显的下降和上升波峰,而血清中LH和E2水平没有发生明显变化。     

奶牛肢蹄病的防治与治疗

<正>奶牛肢蹄病是奶牛四肢和蹄部疾病的总称,是危害奶牛生产的三大疾病之一,是影响奶牛寿命的主要因素。1发病原因1.1营养因素日粮中无论缺钙还是缺磷,无论是高钙低磷还是高磷低钙,都容易导致钙磷代谢障碍,从而引起奶牛肢蹄病。⑴缺锌:锌是许多金属酶类和激素如胰岛素的组成部分,与皮肤的健康有关,蹄是皮肤的衍生物,日粮中缺锌,影响蹄角化,容易发生腐蹄病。⑵维生素D不足或活性下降:维生素D不足或活性下降时,引起钙、磷代谢障碍。某些曲霉菌素中毒会干扰维生素D的活性,即使钙、磷充足     

狗妈认养猫孩子 母性大发自行产奶

<正>都说"猫狗天生是冤家",不过对于家住镇海区港城花园的林先生来说,他家的猫和狗可不是一般的和谐。而且从未生过小狗的狗妈妈,因为两只小猫而开始产奶。昨天,林先生将最近发生的这件事发到了网上,许多网友在关注之余也表达了赞叹:"小狗好有爱心","这狗很牛"。小狗出门捡了两个猫孩子上个星期的早上我们家小狗"妞妞"出去方便和放风的时候,从外面捡回来两只可怜的小猫,我试着把小猫放到它怀里,它很高兴,不再哼了,     

Effect of Nutrient Restriction and Compensation on Weight,Serum Indexes and Gene Expression of Chest Fat Adipokines in Mongolian Lamb

To study the effect of nutrient restriction and compensation on weight,serum indexes and gene expression of chest fat adipokine in Mongolian lamb,thirty male lambs were randomly divided into control group (20.26 kg± 3.63 kg) and feed restricted group (21.29 kg±3.00 kg).The experiment lasted for 120 days,including 60 days for feed restriction and 60 days for compensatory feed.At the end of each stage,five lambs from each group were slaughtered and chest fat was collected.Serum concentration of triglycerides,non-esterified fatty acids (NEFA),total cholesterol were measured.Quantitative Real-time PCR were used to determine Adiponectin,Visfatin,PPAR-γ and ACC genes expression.The results showed that:①The lamb body weight of restricted group kept maintain level and that of control group showed a increase tendency.During the compensatory period,the average daily gain (ADG) of restricted group was significantly higher than control group (P< 0.05).②During the restriction period,serum triglycerides concentration of lambs in restricted group was significantly decreased at day 30 and 60 (P< 0.05),and NEFA concentration was significantly increased at day 30 (P< 0.05).After 60 days of nutritional compensation,all serum parameters we tested were not significantly different between restrict group and control group (P >0.05).③During the restriction period,PPAR-γ and ACC gene expression in restricted group were significantly lower than that of control group (P< 0.05),while no significant differences were found during the compensation period (P>0.05).Adiponectin and Visfatin genes expression in chest fat was not significantly changed throughout the experiment (P >0.05).We could know that nutritional restriction reduced fatty acid synthesis and adipocyte differentiation ability,adipose tissue was mobilized energy metabolism,and total cholesterol was recoveried growth on the compensation.However,the ACC and PPAR-γ genes in restricted group were significantly decreased with the body weight increased rapidly during the compensatory stage.Adiponectin and Visfatin were not significantly different between restricted and compensatory stages.     

HPLC法同时测定皖贝母两种生物碱成分含量

建立皖贝母生物碱测定方法。采用高效液相色谱仪-蒸发光散射仪对皖贝母中的贝母甲素、贝母乙素含量进行测试。高效液相色谱仪-蒸发光散射仪测试贝母甲素、贝母乙素结果分别为0.203~0.251mg/mL、0.472~0.508mg/mL平均加样回收率分别为98.74%及100.34%,RSD分别为1.08%及0.95%。本法准确可靠,重现性好,可用于皖贝母的质量控制。     

应用白杨透翅蛾性诱剂诱杀白杨透翅蛾成虫的实验

通过几种试验比较,找出诱杀白杨透翅蛾成虫更为合理的方法,并加以分析。