Direct immunoflourescence staining (IF) and indirect IF (IIF) were carried out by using antisera against Cff strains 0020, 0237, 0238 and its FITC conjugates.

• 试验中制备了抗Cf的血清，应用抗0020，0237，0238菌株的抗血清及其FITC标记的抗体进行间接和直接免疫荧光染色试验（IF/IF）。