The elevation of egg production and the inhibition of incubation behavior are the aims of modern
poultry production. Prolactin (PRL) gene is confirmed to be critical for the onset and maintenance of these
reproductive behaviors in birds. Through PRL, dopamine D1 receptor (DRD1) was also involved in the regulation of
chicken reproductive behavior. However, the genetic effects of this gene on chicken egg production and
broodiness have not been studied extensively. The objective of this research was to evaluate the genetic effects of
the DRD1 gene on chicken egg production and broodiness traits