Vol. 9, Issue 12, Part I (2025)

The present investigation was conducted to determine the status of the infection in the chicken population based on epidemiology status of infection in Assam India. During the period of study, outbreaks were reported from five different locations of Kamrup (Metro) district, Assam. A total of 80 cases were recorded with the presence of nodular growth, and out of these, 73 nos. showed positivity for Marek’s Diseases on the pathological and molecular detection. The overall mortality percentage of MD was recorded as 5.93% indicating that the presence of Marek’s disease virus infection in Kamrup (Metro) district, Assam. The mortality percentage was persistent in different age groups and highest (10.98%), mortality was recorded in 8-<12 weeks of age group followed by the 12-<16 weeks (6.51%), 16-<20 weeks (6.50%), < 8 weeks (4.80%) and > 20 weeks (2.46%). Breed/strain wise highest mortality was observed in high yielding layers viz. BV-300 and BV-380 with a rate of 7.52% and 6.88% respectively followed by backyard breeds i.e. Rainbow roaster, Kamrupa and Daothigir with a mortality of 5.07%, 4.29% and 3.81% respectively. Season wise highest mortality was recorded during pre-monsoon (7.87%) followed by monsoon (6.06%), winter (4.48%) and post-monsoon (3.10%).