Mycoplasma infection causes arthritis in limb joints in pigs, while infection with M. hyopneumoniae gave rise to symptoms of coughing and chronic pneumonia and the disease is called as enzootic pneumonia of pigs. The incubation period of the disease is 10 – 16 days. The animal shows poor and stunted growth with mild fever. The disease can be identified on the basis of isolation and identification of the organism followed by other serological tests, like CFT, IHA and ELISA. The PCR and PCR- RFLP and other advance diagnostic tools are helpful in diagnosis of infection.