Residue depletion of sulphadiazine and trimethoprim in pigs and broilers after oral administration.

The residual behaviour of a sulphadiazine (SDZ) and trimethoprim (TMP) combination was studied in fourteen pigs and twenty-eight broilers. The drug combination was added in the amount of 700 mg kg-1 (SDZ) and 140 mg kg-1 (TMP) to pig and 300 mg kg-1 (SDZ) and 60 mg kg-1 (TMP) to broiler feed, respectively. The medicated feeds were supplied for 5 consecutive days. The tissue SDZ/TMP concentrations were measured by a HPLC method. To ensure safe residue levels in all target tissues, withdrawal time of 8.6 days and 6.0 days should be applied to pigs and broilers, respectively, treated with SDZ and TMP in feed.