Dynamic of HVT load in feathers per subject over time. Each HVT load corresponds to the log10 of HVT genomes number per million cells. Each dot corresponds to the HVT load at a time point. When the dot is missing, the datum was missing. Missing data were numerous for the pH birds after week 24, due to the lack of growing feathers. The birds exhibited two major profiles: (i) persistent high loads or variable loads with positive loads interspersed with null loads (e.g. Fa04 and Fa08, respectively); (ii) low producer profile including controllers (indicated by a red star), with several successive zero loads notably from week 14 and including at week 41 (e.g. He03 and Nu03). The low producers but not controllers are marked with a black star (*), like Fa10 due to its positivity at week 41.