TABLE 3.
Proportion of birds colonized by the parental strain (197N) compared to an avirulent Dnt− mutant strain (WBA16) as a function of time
| Days postinfectiona | % (SD) of birds colonizedb
|
|
|---|---|---|
| Parent | Dnt− | |
| 0 | 0 (0) | 0 (0) |
| 3 | 100 (NCc) | 20 (NC) |
| 7 | 100 (0) | 25 (35) |
| 14 | 100 (0) | 0 (0) |
a
Zero refers to preinoculated birds.
b
Five birds were removed on each designated day and swabbed for B. avium, as described in the text. All birds received an average of 2 × 1010 CFU of B. avium on day zero and were kept in groups of 10 birds per brooder. Birds used were of the BUT-A line.
c
NC, not possible to calculate because only one experiment examined the 3-day time point. Other values are averages of two separate experiments.