Table 6.
Viable counts of test (Nalr) and challenge (Spc) mutants of S. Typhimurium F98 in the ceca of newly hatched chickens in a competition assaya
| Mutation | Viable count ofb: |
||
|---|---|---|---|
| Test strain |
Challenge strain postmortem | ||
| At time of challenge | Postmortem | ||
| metF | 8.32, 8.42, 8.59 | 7.17 (6.60–7.82) | <2 (<2–<2) |
| csgA | 8.40, 7.64, 8.04 | 7.79 (7.18–8.18) | <2 (<2–<2) |
| ttrS | 7.73, 6.30, 7.08 | 6.95 (6.00–7.79) | <2 (<2–2.85) |
| ttrB | 7.93, 8.43, 9.11 | 7.74 (7.00–8.00) | <2 (<2–<2) |
| pdu | 8.08, 8.04, 8.00 | 6.60 (6.00–7.65) | <2 (<2–5.2) |
| eut | 8.2, 8.88, 9.00 | 7.59 (7.18–7.68) | <2 (<2–<2) |
| argA | 7.11, 7.88, 7.28 | 6.00 (6.00–6.90) | <2 (<2–2.78) |
| potG | 7.90, 7.83 | 6.95 (6.70–7.28) | <2 (<2–<2) |
| Parent | 8.80, 8.18, 8.28 | 7.00 (6.60–8.57) | <2 (<2–<2) |
| None | <2, <2, <2 | <2 (<2–<2) | 4.3 (4.00–7.82) |
a
Ten chickens were inoculated with the test strain. Three chickens were killed to enumerate this strain 24 h later at the time of challenge. All chickens were killed 3 days later to enumerate both strains in the ceca.
b
Viable counts at time of challenge are presented for all three chickens. Viable counts postmortem of all other chickens are the means and ranges.