Number of fusants detected over 28 days in a rat model of oral colonization. The figure shows the total number of colony forming units (solid symbols) and the number of fusants (open symbols) recovered by swabbing the oral cavities of a set of three rats (each represented by a differently shaped symbol) co-inoculated orally with opaque cells of strains W43a–pNZ4 and OD8916α–pNZ11. This is one of several experiments with similar outcomes (see Table S2 for outcomes of all experiments and more details).