What is the fine-grained topic of the following text: From these results, it is assumed that the macroscopical and histopathological changes in duck palate resembling the findings observed in acatalasemia cases were caused by the oxidative action of deposit of hydrogen peroxide generated by Diplococcus pneumoniae (Type Ⅱ). Only return the topic.
Oxidative effects of Diplococcus pneumoniae on duck palate resembling acatalasemia cases.