Marek's disease in vaccinated poultry flocks in and around Namakkal region of Tamil Nadu Arulmozhi A.*,3, Saravanan S.1,3, Mohan B.2,3, Balasubramaniam G.A.3 3Department of Veterinary PathologyAvian Disease LaboratoryVeterinary Hospital Campus, Namakkal-637 002, Tamil Nadu 1Avian Disease LaboratoryVeterinary Hospital Campus, Namakkal-637 002, Tamil Nadu 2Veterinary Hospital Campus, Namakkal-637 002, Tamil Nadu *Corresponding author; e-mail: arulvinod2000@yahoo.co.in
Abstract The present study reports the mortality pattern, varying age susceptibility and altered gross pathology due to Marek's disease in white leghorn layers. A huge Marek's disease outbreak occurred even in vaccinated white leghorn layers farms in and around Namakkal district of Tamil Nadu resulted in severe economic loss to the poultry farmers and closure of small farms too. Epidemiological data were collected and the average flock mortality was about 10–40%. On clinical examination, the birds were weak, pale, off feed, poor performer, diarrhoeic, culls and showed nervous signs and blindness. Grossly, there was hepatomegaly, spleenomegaly, hypertrophy of the proventriculus and tumour nodules in ovary and kidneys. Histopathologically, there was severe pleomorphic lymphocytic infiltration in liver, kidneys, ovary and nerves. As a consequence of the huge MD outbreak, the vaccine strategy was changed and now it is being practiced. Top Keywords Marek's disease, Vaccination, White leghorn layer. Top |