FIG. 4.

Mapping the presence of the classical or alternative O-antigen genes to ST in 49 B. bronchiseptica strains. A neighbor-joining tree with 1,000 bootstraps based on concatenated MLST gene sequence of 49 B. bronchiseptica isolates is shown. The identification number of each strain, the ST, and the complex to which each strain belongs are listed. STs and complexes have been described previously (6, 6a, 9). The highlighting indicates strains that contained either the classical (dark gray) or alternative (light gray) locus or were PCR negative for either locus (no highlighting). The numbers on the tree branches indicate branch strength. All branch strengths below 50 were removed.