Thymic E4bp4 gene transcription is up-regulated in the chicken during experimental peritonitis modified by the season-related lighting conditions.

Immunity, like other vertebrate processes, undergoes the diurnal and seasonal rhythmicity generated and synchronized by the endogenous clock. In the present study a transcription of the selected clock genes was evaluated in the chicken thymus to verify its supposed role as a peripheral clock and to check its relation with the seasonality of immune function. Chickens kept from hatch in the season-related lighting conditions (LD 16:8 in summer vs 8:16 in winter) and in a controlled temperature were exposed to the experimental peritonitis elicited by i.