To further investigate the ability of the αvβ6-expressing cell types to support the production of non-cell culture adapted FMDV, additional infection experiments were performed using a low MOI (0.005) and FMDV strains belonging to the O, A, SAT1 and SAT2 serotypes; these FMDV had been passaged (<3 passages) in primary bovine thyroid (BTY) cells following collection from the field and were considered not to be cell-culture adapted. This evidence concerns the gene SAT1 and infection.