A total of sixty fluid exudate samples aspirated from the infra-orbital sinus of turkey poults suf-fered from respiratory manifestations were exam-ined for mycoplasma infection. Mycoplasma syn-oviae could be isolated from 13.33% of samples, while M. gallisepticum was recovered from only 6.66% of the examined samples. Sodium dodecyl sulfate-polyacrylamide gel elec- lophoresis (SDS-PAGE) revealed the presence of some differences in the protein makeup of M. Synoviae field isolates compared with that of the Standard reference strain, which indicates strain variability. However, M. gallisepticum reference Suain and field isolates revealed largely similar c , ,lectrophorctic paticrns of their cell proteins. The efficacy of enrofloxacin, lincospectin and ty-losin as antimycoplasmal drugs for the treatment of turkey poults naturally infected with M. synovi-ae and M. gallisepticum was studied. The mini-mum inhibitory concentration (MIC) of enroflox-acin ranged from 0.006 to 0.012 (pg/ml, lincospectin was 0.024 (g/ml, while tylosin had the least activity (0.024-0.048 (g/ml). Mycoplas-ma could be re-isolated from only one of 20 tur- key poults treated with enrofloxacin, 3 out of 20 birds treated with lincospectin and 5 out of 20 birds treated with tylosin.