Table 2. Origins of Salmonella-positive samples in contaminated layer farms.
| Locations | Farm A | Farm H | |||
|---|---|---|---|---|---|
| Contamination rate1 | Key2 | Contamination rate | Key | ||
| Henhouses | Feed | 1/27 (3.7%) | 1 | 0/27 | — |
| Drinking nipples | 1/27 (3.7%) | 2 | 3/27 (11.1%) | 23–25 | |
| Egg belt | 0/27 | — | 1/27 (3.7%) | 26 | |
| Air inlets | 2/9 (22.2%) | 3, 4 | 1/9 (11.1%) | 27 | |
| Air outlets | 3/9 (33.3%) | 5–7 | 0/9 | — | |
| Air | 2/9 (22.2%) | 8, 9 | 1/9 (11.1%) | 28 | |
| Overshoes | 2/6 (33.3%) | 10, 11 | 1/6 (16.7%) | 29 | |
| Eggshells | 5/30 (16.7%) | 12–16 | 0/30 | — | |
| Egg collecting areas | Air | 2/9 (22.2%) | 17, 18 | 0/9 | — |
| Overshoe | 0/6 | — | 0/6 | — | |
| Eggshell | 4/30 (13.3%) | 19–22 | 2/30 (6.7%) | 30, 31 | |
| Total percentage | 11.6% | 4.8% | |||
1
Number of contaminated samples/number of detected samples for each sample type are shown, with the percentage in parentheses;
2
Contaminated samples were assigned unique key values.