Carbadox and sulfamethazine as growth promoters in two swine herds with atrophic rhinitis

Two trials were conducted with recently weaned 9-kg pigs fed to 95 kg, when naturally affected with atrophic rhinitis, to determine the effect of feeding carbadox and sulfamethazine, alone or in combinaton, up to 35 kg liveweight, on the performance of pigs fed to 95 kg. Trial locations, using similar management practices, were selected in Ontario and Saskatchewan based on a previous history of chronic atrophic rhinitis. In the starter period, carbadox fed alone or in combination with sulfamethazine, improved (P 0.05) FE. When starter and grower periods were combined, significant (P 0.05) in feed efficiency as compared to carbadox alone, this was not considered to be additive. Use of the medications did not result in a reduction of mean nasal lesion score due to atrophic rhinitis. Key words: Carbadox, sulfamethazine, atrophic rhinitis, pigs