TABLE 3.

Mortality, lesion scores, and recovery of challenge E. coli from infected chickens

Challenge E. coliMortality (%)Mean lesion score ± SEMRecovery of E. coli
DirectaTotalb
Aerosol challenge
    Wild-type Ec222153.65 ± 0.65c43/6056/60
    Ec222 vat deletion mutant00.11 ± 0.079/6032/60
Cellulitis challenge
    Wild-type Ec222335.0 ± 0.25c12/12NDd
    Ec222 vat deletion mutant00.01 ± 00/12ND
  • a Number recovered by direct plating of swabs on MacConkey agar/total.

  • b Number recovered by culture of swabs in Trypticase soy broth followed by subculture on MacConkey agar/total.

  • c Significantly higher than that for lesions caused by infection with for Ec222 vat mutant. P = <0.0001. Maximum score was 7.0. Normal was scored as 0.01.

  • d ND, not done.