TABLE 2.
Detection of salmonellae in liquid egg from four plants and serotypes of the isolates in the autumn of 2003
| Parameter | Egg-breaking plant
|
|||
|---|---|---|---|---|
| A | B | C | D | |
| No. of tested samples | 28 | 26 | 28 | 28 |
| No. of samples in which salmonellae were detected (%) | ||||
| Culture method | 26 (92.9) | 24 (92.3) | 22 (78.6) | 27 (96.4) |
| LAMP assay | 27 (96.4) | 24 (92.3) | 22 (78.6) | 27 (96.4) |
| PCR assay | 27 (96.4) | 20 (76.9) | 16 (57.1) | 26 (92.9) |
| Total | 27 (96.4)a | 24 (92.3)b | 22 (78.6)c | 27 (96.4)d |
| No. of samples in which salmonellae were undetected (%) | 1 (3.6) | 2 (7.7) | 6 (21.4) | 1 (3.6) |
| No. of sampling days | 14 | 13 | 14 | 14 |
| No. of days salmonellae were detectede | 14 | 12 | 13 | 14 |
| No. of days serovar Enteritidis was isolated | 12 | 5 | 10 | 12 |
| Mean bacterial no. ± SD (log CFU/g) | 4.20 ± 0.30 | 3.92 ± 0.41 | 5.03 ± 0.59 | 4.29 ± 0.52 |
| Serotype of isolate (no. of strains)f | Enteritidis (17) | Braenderup (11) | Enteritidis (13) | Enteritidis (16) |
| Cerro (6) | Enteritidis (8) | Cerro (10) | Mbandaka (7) | |
| Emek (4) | Typhimurium (3) | Infantis (8) | Thompson (5) | |
| Infantis (3) | Virchow (3) | Thompson (2) | Infantis (4) | |
| O35:Z4,Z23:− (3) | Cerro (2) | Haifa (1) | Typhimurium (3) | |
| Corvallis (2) | Infantis (2) | Mbandaka (1) | Cerro (2) | |
| Derby (1) | Lockleaze (2) | Montevideo (1) | Corvallis (2) | |
| Havana (1) | Agona (1) | Hadar (1) | ||
| Livingstone (1) | Bareilly (1) | Heidelberg (1) | ||
| Mbandaka (1) | Yoruba (1) | Schwarzengrund (1) | ||
| Saintpaul (1) | Virchow (1) | |||
| Thompson (1) | O8:Z4,Z24:− (1) | |||
| Virchow (1) | ||||
a
Contained one sample which was positive by LAMP and PCR assays but not by culture method.
b
Contained four samples which were positive by culture method and LAMP assay but not by PCR assay.
c
Contained six samples which were positive by culture method and LAMP assay but not by PCR assay.
d
Contained one sample which was positive by culture method and LAMP assay but not by PCR assay.
e
Detected by some of the three methods.
f
Isolates of the same PFGE pattern in same samples was regard as one strain. A total of 25 serotypes were isolated.