Udhayavel, ShanmugasundaramGopala Krishna Murthy, Tippichettypalayam RamasamyGowthaman, VasudevanSenthilvel, KandasamySureshkumar, GanesanTANUVAS2018-07-132018-07-132016-08http://krishikosh.egranth.ac.in/handle/1/5810060090TNV_AAVS_2016_4(8)438-440Chronic Respiratory disease in Poultry is mainly caused by Mycoplasma gallisepticum (MG). It causes huge economic loss to the poultry industry. The present research work has been undertaken to know the sero-prevalence of MG in commercial layers in Namakkal region of Tamil Nadu, India. A total of 103 commercial layer sera samples from 6 commercial layer farms were subjected to indirect ELISA. From 103 sera samples, overall prevalence found 53.40% for commercial layer chickens. The highest (100%) sero-prevalence of MG was recorded at 32 weeks and the lowest (0%) was recorded at 68 weeks of commercial layer chicken. This study demonstrated high sero-prevalence of MG in Commercial Layers. Therefore, routine monitoring of the commercial layer farms for MG infection should be recommended and mycoplasma control programmes must be strictly adhered.enVeterinary ScienceArticle