TABLE 5.
Distribution and genetic link to selC of genes aec-35, aec-36, and aec-37 in a collection of pathogenic and nonpathogenic E. coli strainsa
| DNA region amplified | No. of strains positive
|
||
|---|---|---|---|
| Avian pathogenic strains (n = 205) | Avian nonpathogenic strains (n = 44) | Human and animal pathogenic strains (n = 36) | |
| aec-35 | 27 | 4 | 4 |
| aec-36 | 26 | 4 | 3 |
| aec-37 | 26 | 4 | 3 |
| aec-35 to aec-37 | 26 | 4 | 3 |
| selC to aec-35 | 25 | 4 | 3 |
a
Pathogenic strains of avian origin were isolated from chickens or ducks with signs of colibacillosis and were able to kill at least four of five day-old chicks inoculated subcutaneously with 108 CFU. Nonpathogenic strains of avian origin were isolated from the gut of healthy birds and were unable to kill any chick in the day-old chick lethality model (16). Other pathogenic strains were isolated from pathological samples.