7.Setting

Setting

Eggs with the same origin and production characteristics are placed in setter trays after being gradually warmed up in a setter room or incubator. The embryo in a hatching egg is a living being that develops, in stages, from a single cell stage into a fully-fledged chick. Keep this in mind at all times. During the first 10–12 days, the temperature has a particularly important effect on embryonic growth You need to know the following copyright protected before setting each batch and development. After that period, the embryo of eggs: adapts tentatively to the microclimate. From • The quality of the hatching eggs the sixteenth day, the embryo reacts to exces(eggshell quality, age, parent stock, results sively high or low temperatures by increasing or of the previous batch set, storage time) decreasing its heart rate. With a higher heart rate, • Incubation conditions more heat is transferred to the eggshell, while the (program: temperature, relative humidity, embryo retains its metabolic heat at a lower rate. ventilation, turning) However, embryos only have very limited capacity • Developments in the hatching egg for temperature regulation. This is mainly depend(% fertile, early embryonic mortality) ent on environmental conditions. An embryo can survive well for a few hours with a lower ambient • Assessment of the previous hatchability (% hatched and chick quality) temperature (25-28°C). A longer period with an excessively high temperature (> 39°C) has a negative effect on embryo development, and on the heart in particular.