During incubation of chicken eggs, the first candling is usually carried out after_____________

The correct answer is "six days." Candling is a process of shining a bright light through an egg to observe the growth and development of the embryo inside. During incubation of chicken eggs, candling is usually done at several points to monitor the growth and development of the embryo and check for any problems or defects. The first candling is typically carried out after six days of incubation. At this stage, the embryo should have developed to a point where it is visible when a bright light is shone through the eggshell. The candling process at this stage allows the farmer to check for any signs of embryo development, such as the presence of veins or blood vessels, and to identify any clear or unfertilized eggs that can be removed from the incubator. Subsequent candlings are typically done at around ten and eighteen days of incubation, to monitor the continued growth and development of the embryo and check for any potential problems. The final candling is usually done on the 21st day, which is the day that the chicks are expected to hatch. At this point, the farmer can identify any eggs that have not developed properly and remove them from the incubator.