Figure 2. Phylogenetic tree based on nox gene sequences (893 nt) showing the evolutionary relationships among Brachyspira spp. isolates from graylag geese and mallards.

The tree was constructed using the neighbour-joining method. The bar represents the distance equivalent to 10 substitutions per 100 nucleotide positions on the upper subbranch. "B. corvi" AN968/2/04 was used as an outgroup. The main clusters were designated I-VII.