Treatment of experimental Bordetella bronchiseptica infection in young pigs with potentiated sulphonamide in the drinking water.

Bordetella bronchiseptica was eliminated from the nasal cavity of experimentally infected piglets after about three weeks by trimethoprim and sulphadiazine (potentiated sulphonamide) in the drinking water in two experiments (at levels of 13.3 and 66.7 micrograms per ml, respectively). The rhinitis and turbinate damage associated with the infection was significantly less when the animals were examined at seven weeks of age but daily weight gain was not improved to a significant extent compared with controls. Smaller quantities of potentiated sulphonamide were less active but no amount induced resistance in the bordetellae during the one month period of treatment.