Adel Feizi, Soroosh Babakhani and Hossein Nikpiran
Mycoplasma gallisepticum (MG) is one of the most important diseases in Iranian poultry industry and all over the world. Mortality, poor weight gain and increasing of feed conversion ratio (FCR) were seen in MG infected flocks. Several drugs are used for prevention and control of MG, the purpose of this study was to investigate Tiamulin and Tylosin efficacy on MG, and its role on broilers performance. In this study, 240 Ross 308 broilers divided in 3 groups. In two groups Tiamulin and Tylosin was used in days 3 to 5 and later in days 19 to 21, 100 grams in 200 Litters of water and in last group placebo was used and that group mentioned as a control group. Gross lesions, mortality, and growth parameters include body weight gain, feed intake and FCR were calculated in all groups weekly. Results showed that in treatment groups mortality percent was significantly (p<0.05) lower than control group and pericarditis, perihepatitis and airsacculitis was sever in control groups in comparison to antibiotic treated groups. Also body weight and FCR was significantly were different between control group and Tylosin and Tiamulin groups (p<0.05). It can be concluded that usage of these antibiotics can be prevent MG economical losses in poultry, and in MG positive chickens use of this antibiotic in mentioned periods could improve broilers performance
