Table 1. Macrolide- and rifampin-resistant Rhodococcus equi on horse breeding farm, Kentucky, USA*.
| Year | No. foals born | No. (%) foals with lesions treated | No. foals tested | No. foals with positive R. equi culture | No. (%) foals with macrolide- and rifampin-resistant R. equi |
|---|---|---|---|---|---|
| 2001 | 95 | 30 (32) | 30 | 30 | 0 |
| 2002 | 117 | 53 (45) | 0 | NA | NA |
| 2003 | 148 | 58 (32) | 2 | ? | ? |
| 2004 | 181 | 88 (49) | 28 | 19 | 0 |
| 2005 | 168 | 70 (42) | 30 | ? | ? |
| 2006 | 170 | 42 (41) | 5 | 2 | 0 |
| 2007 | 181 | 93 (51) | 4 | ? | ? |
| 2008 | 171 | 52 (30) | 21 | 16 | 4 (25)† |
| 2009 | 162 | 50 (31) | 30 | 22 | 5 (23)† |
| 2010 | 138 | 45 (33) | 28 | 22 | 9 (41)† |
| 2011 | 132 | 24 (18) | 27 | 25 | 9 (36)† |
*NA, not applicable; ?, data missing from farm records. †Includes pretreatment and posttreatment isolates.