Immunological characterization of peripheral blood leukocytes using vaccine for mycoplasmal pneumonia of swine (MPS) in swine line selected for resistance to MPS

This study was conducted to evaluate immunological changes in peripheral blood leukocytes in pigs that were genetically selected for their improved resistance to mycoplasmal pneumonia of swine (MPS), using MPS vaccine as an antigen. Twelve castrated MPS‐selected Landrace pigs were compared with the same number of pigs from a nonselected line by using a time‐course analysis at the hematological level. After the second sensitization with MPS vaccine, the percentages of B cells, CD4⁺ T cells, and natural killer (NK) cells in total leukocytes were lower in the selected line than in the nonselected line, whereas the percentage of granulocytes in total leukocytes increased in the MPS‐selected line. We also assessed the proliferative ability of peripheral blood mononuclear cells (PBMCs) stimulated with Mycoplasma hyopneumoniae, lipopolysaccharide or concanavalin A, and found that although the proliferative ability of the PBMC was not different between the two lines at a steady state, the nonselected line showed a significantly higher proliferative ability after sensitization with MPS vaccine than the selected line regardless of antigens used. These results thus indicate that the selection of pigs on the basis of MPS resistance changes their immunophenotype, and would give us beneficial information for the prevention of MPS infection.     

利用ISSR分子标记进行不同来源大豆品种的分类

采用ISSR分子标记技术对不同来源大豆品种(系)进行了分类研究,对UBC ISSR801-850引物进行筛选,发现有11个引物没有产物,选出39个引物具有扩增产物,一般每个引物可以扩增出1-6条带,产物片段大小多在831-3530b之间.39个引物共扩增出121条带,其中多肽性带47条,占38.84%.每个引物平均可扩增出带数为3.1条;其中多肽性带数为1.21条.ISSR引物扩增的结果表明,ISSR分子标记技术能很好地用来区分不同来源的大豆品种(系).不同大豆品种(系)因其遗传背景不同,经ISSR引物扩增出来的谱带数也不一样,而且不同品种(系)还具有特异性的标记谱带.另外,对沈农系列大豆品种(系)的生产力与本试验采用的日本大豆品种的比较分析可以看出,沈农系列大豆品种(系)的生产力要高于日本大豆品种的生产力.     

不同基因型对白菜子叶培养不定芽再生的影响

探讨了基因型对白菜子叶培养不定芽再生的影响。结果表明，不同基因型的不定芽再生率和平均每子叶生芽数差异极大，在被检索的123个大白菜和20个小白菜品种中，芽再生率为0－97.5%，平均每子味生芽数为1.0-10.7个。17个大白菜和5个小白菜品种的不定芽再生率在80％以上。芽再生率与品种起源地、结球类型及熟性无相关。