On a Swiss nucleus sow breeding farm with 170 sows and 600 gilts/fatteners, an eradication of swine dysentery as modified partial depopulation was conducted in stages over a period of 12 weeks in 2011 after Brachyspira (B.) hyodysenteriae was detected in the herd. In addition to administering oral medication (8.1 mg tiamulin per kg body weight) for 4 weeks to the pigs remaining on the farm, all stables were cleaned thoroughly and the residual slurry was disinfected with Alzogur(®) (3 l/m(3)) while the surfaces were disinfected with Venno Vet 1 Super(®) (1.5 %). At the same time rodent and fly control was intensified. Upon completion of the eradication programme, the farm was monitored for 6 months by carrying out fecal swab analyses of pigs with diarrhea. All fecal samples were negative for B. hyodysenteriae. The costs of the eradication amounted to approximately CHF 104'500. The eradication yielded significantly higher live daily weight gain (+ 23.8 g, ± 10.1 g, P < 0.0001). This improved performance resulted in an additional economic benefit of CHF 18,500 per year.