DETECTION AND SEROTYPING OF MAREKS DISEASE VIRUS IN DISEASED CHICKENS IN ABEOKUTA
Outbreaks of Marek’s disease (MD) in vaccinated flocks still occur sporadically and lead to economic losses. This study reports the detection of serotypes 1 and 3 Marek’s disease virus using molecular techniques in pullets showing clinical signs of the disease. An enzyme-linked immunosorbent assay (ELISA) was applied to evaluate the antibody response of chicks and the diseased pullets from the same parent stock against Marek’s disease (MD) at 4 and 21weeks of age respectively. Despite vaccination at day old, antibody titre in the chicks was negative while it was highly variable in the diseased pullets. From the results, the susceptibility of previously vaccinated birds to the pathogenic strain of MDV indicates inappropriate vaccination at day old and a call for concern in the poultry industry. It is therefore recommended that serology be carried out on birds to determine their immune status before and after MD vaccination.