Effects of microbial isolates on porcine tracheal and bronchial explant cultures as observed by scanning electron microscopy.

Porcine tracheal and bronchial explant cultures exposed to log-phase cultures of Bordetella, Candida, Corynebacterium, Haemophilus, Klebsiella, Mycoplasma, Pasteurella, Proteus, Saccharomyces, Staphylococcus and Streptococcus were examined for surface sequential changes by scanning electron and light microscopy. Infected tissues, observed microscopically, had diminution or cessation of ciliary activity, and histologically had exfoliation of cilia, ciliocytophthoria, elevation of cellular borders, and cellular detachment. Treatment of these tissues with sterile medium containing penicillin and streptomycin did not prevent death or alteration of cells with increasing periods of incubation. The potential value of using scanning electron microscopy with explant cultures for studying organization of cellular surfaces in association with microbial growth and pathogenesis was demonstrated.