[Brush biopsy as a new examination method of the upper respiratory tract in cattle and swine].

Several techniques of cytobrush sampling were developed for morphological examination of upper respiratory tract epithelium in cattle and swine. These techniques were evaluated in 30 cattle and swine each, with an age of two weeks to nine years and three weeks to four years respectively. Optimal anatomical locations for sampling were determined. Three cytobrushes of different shapes were constructed to optimize sampling in animals of different ages. Two out of four cytobrush sampling techniques developed provided sufficient cellular material and worked well under field conditions. Rinsing with 0.9% saline largely eliminated mucus and other interfering substances.