Outbreak and management of Mycoplasma gallisepticum infection in desi chicken and turkey flocks in an organized mixed farm

In an organized farm, desi chicken and turkeys were reported with the clinical signs of congestion of conjunctival mucous membrane, dullness, unilateral and bilateral head swelling and nasal discharge. Flock strength was 545 desi chickens and 296 turkeys of 75 and 50 days old respectively. Morbidity was 3.67 and 6.75% and mortality was 0.91 and 0.67% in chickens and turkeys respectively. On investigation, clinical signs started 12 days after the introduction of desi chicken from another organized farm. In total, 10 chickens and 20 turkeys showed clinical signs, of which 5 desi chicken and 2 turkeys died. On necropsy, the birds showed congestion of conjunctival mucous membrane, unilateral and bilateral infraorbital sinus swelling and caseous material with mucous exudates in the infraorbital sinus. Lungs were congested and edematous. Thoracic and abdominal air sacs were cloudy with beaded appearance, thickened with yellowish caseous material. Infraorbital sinus and ocular swab were collected from live birds. Infraorbital sinus swab, lung and air sacs were collected from dead birds. Mycoplasma gallisepticum was isolated from infraorbital sinus and air sac samples and was also confirmed by polymerase chain reaction. Histopathologically, mucopurulent sinusitis and airsacculitis were noticed. The Mycoplasma gallisepticum outbreak was effectively controlled by using effective treatment with 1% Tylosin and following strict bio-security measures.