Sulfaquinoxaline and sulfadimethoxine were administered in the drinking water to laying hens, 8 to 10 months, at the recommended maximum dose levels on their prospectuses. Sulfaquinoxaline was used three days on-three days off and three day on procedure; whereas sulfadimethoxine was administered to poults for six successive days. Eggs were analyseç for drug Jesidues duruing the coure of the treatment anç for two weeks of withçrawal. Accomulatimı pattern of both sulfa drugs in eggs were found to be similar between egg-whita and-yolk. However clearanee pattern of these sulfoncrmide derivatives were to be somewhat different between egg-white and-yolk. Sulfaquinoxaline level in egg-white deereased quickly to below O. 1 ppm by five days af ter the withdravn of drug, whereas sulfaquinoxaline level remained in egg-yolk at a plateau Ulıtil six days and thereaf ter decreased slowly to below O. 1 ppm by t~\.'elvedays. Sulfadimethoxine level in egg-white diminished quickly to below 0.5 ppm by four days, O. ıppm by eigth days af ter the cessation of medication. On the other hand, sulfadimethoxine residue in egg-yolk remained at a plateau until five days and thereafter decreased gradually to below O. ı ppm by twelve days. It was determined that 53 to 80 per cent of both drug residues in. eggs which were kept of room temperature for up to thirteen days remained unbroken.

No abstract