Establishment of an experimental model to evaluate the sea bacillus’infectious ability to wounded mouses

Objective: To establish a wound-and-dip model to evaluate the infectious ability of sea bacillus to wounded mouses. Methods: 45 wounded SPF mouses were randomly divided into two groups: the experiment groups（dipped in manual seawater with different sea bacillus） and the control group（diped in the manual seawater without microbe）. After being wounded, mouses were diped for 45 minutes, then feeded in clean feeding cages. 6、12、24、48h and 72h after dipping, life indexes、leucocyte counting、blood cultivation、wound secretion cultivation were observed. Being dead or killed three days later, their hearts,livers,lungs were taken out immediately to perform viscera bacteria culture、pathological examination and nucleic aicd finger mark analysis. Results: The experiment groups were disprited, short-breathed, back-arching and fur-erecting with certain difference among different bacillus. Leucocyte counting rised in both groups in the first 12 hours while experiment groups were more obvious. leucocyte counting began to recover 24 hours later and nearly reached before-wounded level 48 hours later. Wound secretion cultivation in experiment groups had a 100% positive rate while blood cultivation had a positive result in Vibro.parahaemolyticus group at 12 hours only. Bacillus separated from viscera cultured organs of experiment groups were the same kind with the dipping bacillus,which was confirmed by DNA finger mark analysis. Subcutaneous and the striped muscle of experiment groups were soaked by numerous neutrophiles and muscle fiber destoried, alveolate tissue inflammation formed. In control group, there were only few neutrophile in subcutaneous and the striped muscle with muscle fiber normal. Conclusions: This model had a promising value in the inffectious study of sea bacillus.