Marek’s disease is a highly contagious and devastating viral avian disease that affects poultry. It is caused by a herpesvirus, and can have dire consequences for the health of infected birds. Symptoms of Marek’s disease can include paralysis and nervous system disorders, reduced egg production, tumors in the feathers or organs, lameness, and decreased appetite. The virus spreads rapidly and causes acute neurological signs followed by paralysis, loss of appetite and eventual death. In some cases infected birds may die from Marek’s disease but in others they may survive without clinical signs until later in life when tumor formation may occur. Vaccination has been an effective means to prevent outbreaks, however the virus has become increasingly resistant to the current vaccine strains. Additionally, stressors such as overcrowding, poor nutrition, and lack of access to clean water can increase potential susceptibility to infection with the virus. Early detection of Marek’s disease is crucial for preventing it from spreading within a poultry flock.
Below is a link to reputable information about avian health and poultry diseases of high concern in avian flocks.