Figure 2. Bovine mastitis-associated S. aureus isolates was classified according to sdr genes.

Alignment of a partial DNA sequence of sdrC gene of bovine mastitis isolates classifies S. aureus isolates. The same classification can be obtained by alignment of the full sequence of sdrC gene, as shown in Figure S1. sdrC_CQ, sdrC_CE, sdrC_CO and sdrC_CW represent sdrC genes from clinical isolates of Quebec, Eastern Canada, Ontario and Western Canada, respectively. sdrC_Q, sdrC_E, sdrC_O and sdrC_W represent sdrC genes from subclinical isolates of Quebec, Eastern Canada, Ontario and Western Canada, respectively. sdrC_Q&E and sdrC_O&W stand for two different types of sdrC gene in isolates from the Quebec and Eastern Canada region, and from the Ontario and Western Canada region, respectively.