The Effect of Colistin Treatment on the Selection of Colistin-Resistant in Weaner Pigs.

The treatment of diarrhea in the postweaning period is a common reason for the use of antimicrobials in pig production, and is the single most important causative agent for this condition. Colistin has recently been classified as a critically important antimicrobial for human health, as it is a last-resort drug against certain multi-drug-resistant Gram-negative bacteria. Therefore, the use of colistin has been significantly reduced in some countries, including Denmark.