SEC production was measured in the 14 S. aureus strains in milk
and laboratory medium after 48 h of cultivation at 25 C (Table 2).
Results showed a significant decrease in SEC production in milk
compared to TSB (P < 0.0001). However, the level of decrease
(expressed as a ratio¼SEC production inTSB/SEC production in milk)
varied among strains e 1102 lower by SA 1247, versus 2 by SA
1178. Various levels of SEC production among strains in particular
mediumwere also observed (ranging from 0.23 to 73.25 ng mL1 of
SEC in TSB and 0.02e0.61 ng mL1 in milk). Strains grew in both
media and achieved high cell density (Supplemental Table S1). Cell
density was on average higher in TSB: 2.07 (0.71) 109 cfu mL1
compared with 7.24 (2.94) 108 cfu mL1 in milk