Changing trends in mastitis

The global dairy industry, the predominant pathogens causing mastitis, our understanding of mastitis pathogens and the host response to intramammary infection are changing rapidly. This paper aims to discuss changes in each of these aspects. Globalisation, energy demands, human population growth and climate change all affect the dairy industry. In many western countries, control programs for contagious mastitis have been in place for decades, resulting in a decrease in occurrence of Streptococcus agalactiae and Staphylococcus aureus mastitis and an increase in the relative impact of Streptococcus uberis and Escherichia coli mastitis. In some countries, Klebsiella spp. or Streptococcus dysgalactiae are appearing as important causes of mastitis. Differences between countries in legislation, veterinary and laboratory services and farmers' management practices affect the distribution and impact of mastitis pathogens. For pathogens that have traditionally been categorised as contagious, strain adaptation to human and bovine hosts has been recognised. For pathogens that are often categorised as environmental, strains causing transient and chronic infections are distinguished. The genetic basis underlying host adaptation and mechanisms of infection is being unravelled. Genomic information on pathogens and their hosts and improved knowledge of the host's innate and acquired immune responses to intramammary infections provide opportunities to expand our understanding of bovine mastitis. These developments will undoubtedly contribute to novel approaches to mastitis diagnostics and control.     

酒制熟地黄炮制过程中梓醇的变化趋势及变化机理

为研究酒制熟地黄炮制工艺过程中梓醇的变化趋势和变化机理，利用HPLC检测酒制熟地黄炮制过程中不同时间点梓醇的含量，并利用FT-IR结合变温附件获取梓醇在不同温度点的红外光谱信息。结果表明，酒制熟地黄炮制过程中，梓醇含量整体呈下降趋势，但不同时间段梓醇含量下降率不同。梓醇含量下降的原因是其热稳定性较低，在温度90～100℃之间，其结构就发生变化。所以，生地黄产地加工焙干时，温度不能太高，以免梓醇含量下降；熟地黄炮制过程中，时间不能太短，以免“火候”不到。