Table 2.
Survival of Shiga-toxigenic Escherichia coli (STEC) isolates on beef cattle hide pieces by the application of antimicrobial treatment and the multiplicity of infection of phages: STEC host.
| STEC Isolate 1. | Sero-ID | Phages | Water | Control | Phage:Host MOI 3 |
|---|---|---|---|---|---|
| USDA-FSIS 380-94 | O157:H7 | 5.6 ± 0.2B 2 | 6.1 ± 0.2A | 6.1 ± 0.3A | 11.2 |
| CDC 96-3258 | O45:H2 | 5.8 ± 0.1AB | 5.9 ± 0.1AB | 5.8 ± 0.2AB | 47.3 |
| CDC 90-3128 | O103:H2 | 5.2 ± 0.4C | 6.0 ± 0.2A | 5.9 ± 0.2AB | 15.6 |
| JB1-95 | O111:H- | 5.9 ± 0.1A | 5.9 ± 0.2AB | 6.0 ± 0.2A | 41.7 |
| CDC 97-3068 | O121:H19 | 4.7 ± 0.3D | 5.1 ± 0.1C | 5.1 ± 0.2C | 2.2 |
| Pooled Standard Error = 0.07 | |||||
1 STEC isolates provided by J.B. Luchansky (USDA-Agricultural Research Service, Wyndmoor, PA, USA). 2 Values depict least squares means (log10 CFU/cm2) of STEC counts determined from analysis of variance. Values not sharing common letters (A,B,C,D) differ at p = 0.05 by Tukey’s Honestly Significant Differences (HSD) multiple comparisons test. Surviving STEC were enumerated on tryptic soy agar supplemented with 100.0 µg/mL rifampicin. Triplicate identical replicates were completed bearing three identically treated samples per replicate (N = 9). Antimicrobial treatments were: (1) STEC-inoculated non-treated group (Control); (2) STEC-inoculated, sterile distilled water (25 °C); and (3) STEC-inoculated with 108 PFU/mL phage intervention-treated. 3 MOI: Phage multiplicity of infection (MOI) applied in the hide intervention study, calculated as the number of phages applied to hide surfaces divided by the number of bacteria retained on hide surfaces post-inoculation.