vaccine virus replication and shedding in 1-day old chicks.

One-day-old chicks were inoculated intranasally with Ban/AF, B1, or LaSota vaccine virus. Three chicks from each group were euthanized on day 4, 6 and 8 dpi, and oral and cloaca swabs were collected and assayed for infectious virus by inoculation into embryonated chicken eggs. Virus replication was detected by HA assay. The number of virus-positive chicks for each group of three is shown.