Pathogenicity evaluations of infected, uninfected and mock-infected animals at day 14 post-infection.

a Anaemia is defined as a hematocrit value of less than 27.
b The six most affected chicks, based on haematocrit values, were used for microarray analysis.
Gross pathological examination of the thymuses and bone marrows was performed in a blind manner, and a clinical score was estimated by scoring the severity of the thymus atrophy and paleness of the bone marrow, as 0, 1 or 2.