[Hygienic quality of lakes which are used as open-air bath. 2. Communication: Comparison of biochemical typed Escherichia coli strains isolated from lake water and bird excrements (author's transl)].

368 strains of Escherichia coli were isolated from lakewaters and bird excrements (mainly black-headed gulls) using mandatory methods for drinking water examination. All strains were further characterized by 43 biochemical physiological and 30 morphological features. Besides the API 30 E Enterobacteriaceae system and the Roche Enterotube system of biochemical testing were used comparatively. The analysis using numerical methods for taxonomy pointed out that a single biotop could be characterized by the small physiological variation of the strains.