Table 1.
Number of DNP samples, recovered M. haemolytica (Mh) isolates, and macrolide-resistant Mh isolates across all pen-cohorts at each of 1, 13, and 36 DOF. The unadjusted percentages of total and resistant isolates are reported in parentheses.
| Sampling time point | |||
|---|---|---|---|
|
|
|||
| 1 DOF | 13 DOF | 36 DOF | |
| Number of animals sampled | 799 | 798 | 80 |
| Number of Mh isolates recovered (% of total DNP samples) | 264 (33.0) | 421 (52.8) | 60 (75.0) |
| Number of resistant Mh isolates (% of total Mh isolates) | |||
| 15-membered ring macrolides | |||
| Gamithromycin | 1 (0.4) | 351 (83.4) | 44 (73.3) |
| Tulathromycin | 1 (0.4) | 341 (81.0) | 40 (66.7) |
| 16-membered ring macrolides | |||
| Tildipirosin | 0 (0) | 3 (0.7) | 1 (1.7) |
| Tilmicosin | 0 (0) | 25 (5.9) | 7 (11.7) |