Dynamics of Marek's disease virus and herpesvirus of turkey shedding in feather dander of broiler chickens

In an attempt to measure the excretion dynamics of HVT and MDV via feather dander, broiler chickens were vaccinated with HVT or sham-vaccinated at day old and than challenged with MDV at days 2, 4 and 7 post-vaccination. The effect of the interval between vaccination and challenge on the protection of vaccine was determined. MDV and HVT were quantified in the dust samples collected at various days post-placement. There was an effect of the interval between vaccination and challenge on protection, higher the interval, lower the protection. Shedding of HVT was recorded from day 9 to 58 post-vaccination with a peak at around day 20. MDV was recorded in the dust from day 7 to 56 post-challenge with a peak at around 30-35 days post-infection. MDV shedding was significantly reduced by HVT vaccination, higher the protection less the shedding. Identification of HVT and MDV in the same dust sample can be a useful tool for monitoring vaccinal presence and MDV status of a chicken flock by analysing a single dust sample.