Mitochondrial dysfunction influences apoptosis and autophagy in porcine parthenotes developing in vitro

Mitochondria are important regulators of both apoptosis and autophagy. One of the triggers for mitochondrial-mediated apoptosis is the production of reactive oxygen species (ROS), which include hydrogen peroxide, superoxide, hydroxyl radical, nitric oxide and peroxynitrite. Recently, several studies have indicated that ROS may also be involved in the induction of autophagy. In the present study, we used H(2)O(2) to induce mitochondrial stress, examined apoptotic- and autophagic-related gene expression and observed LC3 protein (autophagosome presence marker) expression in porcine parthenotes developing in vitro. In porcine four-cell parthenotes cultured for 5 days in NCSU37 medium containing 0.4% BSA, the developmental rate and mitochondrial distribution did not differ from that of the group supplemented with 100 μM H(2)O(2) but was significantly decreased in the group supplemented with 500 μM H(2)O(2) (P<0.05). Transmission electron microscopy (TEM) indicated that whereas normal shaped mitochondria were observed in blastocysts from the control group, abnormal mitochondria (mitophagy) and autophagic vacuoles were observed in blastocysts from the group that received 500 μM H(2)O(2). Furthermore, addition of H(2)O(2) (100 μM and 500 μM) decreased cell numbers (P<0.05) and increased both apoptosis (P<0.05) and LC3 protein expression in the blastocysts. Real-time RT-PCR showed that H(2)O(2) significantly decreased mRNA expression of anti-apoptotic gene Bcl-xL but increased pro-apoptotic genes, Caspase 3 (Casp3) and Bak, and autophagy-related genes, microtubule-associated protein 1 light chain 3 (Map1lc3b) and lysosomal-associated membrane protein 2 (Lamp2). However, the addition of H(2)O(2) had no effect on mRNA expression levels in nuclear DNA-encoded mitochondrial-related genes, cytochrome oxidase (Cox) 5a, Cox5b and Cox6b1, in blastocysts. These results suggest that H(2)O(2) leads to mitochondrial dysfunction that results in apoptosis and autophagy, which is possibly related to porcine early embryo development.     

霉菌毒素与微量元素代谢及肝脏氧化损伤的关系

<正>霉菌毒素是霉菌在以饲料为营养源的生长过程中产生的有毒化学物质。霉菌毒素在动物体内可产生多种生理作用——肝毒、肾毒、对中枢神经系统的作用以及类似雌激素效应等。有时,霉菌毒素在饲料中的浓度很高,危及动物的健康和生产     

半胱胺对绒山羊瘤胃及盲肠内环境的影响

本试验选用4头6月龄、平均体重为16kg左右、安装永久性瘤胃瘘管和盲肠瘘管的辽宁绒山羊,平均分为半胱胺组和对照组,观察辽宁绒山羊瘤胃及盲肠内环境的变化。结果表明:半胱胺组瘤胃pH较对照组差异不显著(P0.05)。半胱胺组瘤胃NH3-N浓度、瘤胃蛋白浓度较对照组差异显著(P0.05);盲肠pH、蛋白浓度半胱胺组较对照组均差异不显著(P0.05)。本试验结果提示,添加半胱胺后可改变瘤胃内环境,有利于瘤胃微生物蛋白的合成。     

我国陆生动物疫病检测诊断技术标准化发展分析

动物疫病检测和诊断类标准是检测和判断动物疫病的主要依据。本文梳理了我国动物疫病检测和诊断技术标准的建设现状,并将其与我国《一、二、三类动物疫病病种名录》以及OIE《陆生动物疫病诊断和疫苗手册》和《中华人民共和国进境动物检疫疫病名录》中的陆生动物疫病目录进行对比。分析发现:我国动物疫病检测和诊断技术标准体系对我国一、二、三类动物疫病的覆盖率为92.6%,其中80%的标准有PCR和(或)ELISA检测方法 ;对OIE陆生动物疫病诊断和疫苗手册名录疫病的覆盖率为88.3%,其中73%的标准有PCR和(或)ELISA检测方法 ;对我国进境动物检疫名录疫病的覆盖率为87.7%,其中73%的标准有PCR和(或)ELISA检测方法。由此提出了提高我国动物疫病检测和诊断技术标准覆盖率,强化快速诊断检测技术标准化建设的建议。     

基于案例的国内动物疫病风险评估技术发展现状研究

为了解我国动物疫病风险评估研究进展,本研究对我国2006—2016年间发表的动物疫病风险评估模型相关文献进行分析。采用文献回顾的方式,就动物疫病风险评估模型的构建目标、构建方法、评估对象、模型结构及实际应用进行研究。研究表明,我国动物疫病风险评估模型研究与国际基本同步,但也存在理论体系研究薄弱、理论联系实际不足等问题。同时,提出了完善理论体系建设、推广模型应用等建议。     

紫花苜蓿9个盐响应相关基因表达模式

紫花苜蓿(Medicago sativa)是世界上种植面积最大、应用最广泛的豆科牧草。由于其耐盐性中等,其在我国北方地区的产量和种植受到土壤盐渍化的限制。因此提高紫花苜蓿的耐盐性具有重要的科学和生产意义。为此,以龙牧801紫花苜蓿(M.sativa‘Longmu 801’)为试验材料,采用实时荧光定量PCR技术分析了不同浓度NaCl胁迫下9个盐胁迫蛋白质组筛选出的盐响应相关基因的表达模式。结果显示,处理时间和处理浓度对9个基因的相对表达量均有显著性影响,表明这9个基因均在紫花苜蓿盐胁迫应答中发挥着一定作用。处理1h时,G6PI、ABP19a、Trx-h1、PR bet 1、FBPA、6PGDH和ALDH这7个基因的相对表达量在不同NaCl胁迫浓度处理的紫花苜蓿中均显著上调,RRM和GDPD在NaCl处理2h后开始上调。除G6PI基因,其他8个基因在0.4%NaCl处理下相对表达量显著高于0.2%和0.8%NaCl处理。这些基因参与糖代谢、信号转导和胁迫响应。以上结果表明,紫花苜蓿的耐盐性极其复杂,涉及到多基因的表达和代谢通路的调控。研究结果有助于全面研究并了解紫花苜蓿的盐响应相关基因的表达模式,促进紫花苜蓿耐盐分子育种。     

奶粉加工过程中维生素稳定性的研究

研究了维生素在乳粉加工过程中的稳定性.结果表明,原料奶经过均质、杀菌、浓缩、喷雾干燥后,各维生素的损失率分别为维生素A 97.3%、维生素D 94.7%、维生素E 96.7%、维生素B1 93.1%、维生素B2 90.8%;维生素C 99.5%.     

PCR方法扩增种属特异性片段检测猪源成分

针对猪线粒体基因的保守序列,设计特异性引物,优化反应条件和反应参数,建立了食品和饲料中猪源性成分的PCR检测方法。该方法灵敏、特异,检测低限达0.01%。其推广使用,对于加强食品、饲料的质量控制和监督监管,具有参考价值。     

不同导血水平对夏南牛生长发育的影响

本研究把夏南牛各代次、各年龄段牛与南阳牛之间体重做了比较分析;同时与原保留对比试验组的含夏洛来牛血50%和25%的两组横交牛进行比较,结果表明:新品种牛公牛的0、6、12、18月龄四个年龄段与南阳牛相比,体重差异均为极显著(P<0.01).母牛在O、6、12、18、24、30、36月龄各年龄段与南阳牛相比,体重差异均为极显著(P0.05).     

Molecular characterization and phylogenetic analysis of new Newcastle disease virus isolates from the mainland of China

Seventy-nine velogenic Newcastle disease virus (NDV) isolates were obtained from infected chicken flocks during the outbreaks of Newcastle disease (ND) in various regions of the mainland of China in 2006. The F gene fragment (535 bp, from nt 47 to 581 of the F gene) which codes the main functional region of the F protein was obtained by RT-PCR and sequenced. All sequences obtained in this study have been submitted to GenBank. All the isolates have the motif ¹¹²R-R-Q/R-K/R-R-F¹¹⁷ at the cleavage site of the fusion protein, which is typical of velogenic NDV isolates. For genotyping, a phylogenetic tree based on nucleotides 47–435 of the F gene was constructed, and the 79 isolates could be divided into two genotypes, namely VIId and III. Most of the isolates proved to be of genotype VIId; only two isolates were of genotype III. Genotype VIId NDV has been the predominant pathogen responsible for most Newcastle disease outbreaks in China. The proportion of isolates of genotype VIId NDV shows an increasing trend, according to studies on the molecular epidemiology of NDV in China from 2002 to 2006.