If it comes to discussions on fertility two different definitions are practiced. A true fertile egg contains a well developed germinal disc (blastoderm), which indicates that the oöcyte, or zygote, was fertilized and an embryo developed during egg formation. Secondly, in the practice of the hatchery fertility is often based on candling, whereby all clear
THE STRUCTURE OF THE EGG To be well informed of the factors influencing the quality of the egg (both hatching egg and consumer egg) and those of the incubation and hatching process it is necessary to know the structure of the egg. Below you will find a rough enumeration of the most important parts.