Volume 21, Number 6—June 2015
Research
Dose-Response Relationship between Antimicrobial Drugs and Livestock-Associated MRSA in Pig Farming1
, Wietske Dohmen, Marian E.H. Bos, Koen M. Verstappen, Manon Houben, Jaap A. Wagenaar, and Dick J.J. Heederik
Table 1
Characteristics of farms in a study of the dose–response relationship between antimicrobial drug use and livestock-associated methicillin-resistant Staphylococcus aureus in pig farming, the Netherlands, 2011–2013
| Type of farm* | No. farms | Median no. (interquartile range) |
|
|---|---|---|---|
| Sows | Fatteners | ||
| All |
36 |
350 (270–550) |
773 (0–1,950) |
| Open | 22 | 337 (300–500) | 500 (0–1,300) |
| Farrowing† | 9 | 533 (350–800) | 0 |
| Farrow-to finish |
13 |
314 (242–380) |
1,100 (600–2,010) |
| Closed | 14 | 407 (232–698) | 1,400 (450–2,725) |
| Farrowing† | 3 | 439 (239–905) | 0 |
| Farrow-to finish | 11 | 367 (200–673) | 1,892 (1,025–2,950) |
*Farms were defined as open when they received external supplies of gilts ≥1 time per year from at least 1 supplier and as closed when they received no external supply of gilts.
†No fattening pigs present.
1Preliminary results from this study were presented at the 3rd American Society for Microbiology–European Society of Clinical Microbiology and Infectious Diseases (ASM-ESCMID) Conference on Methicillin-resistant Staphylococci in Animals: Veterinary Public Health Implications, 2013 November 4–7, Copenhagen, Denmark (oral presentation, speaker abstract S7:3); and at the Society for Veterinary Epidemiology and Preventive Medicine annual meeting, 2014 March 26–28, Dublin, Ireland (poster presentation).