Variation in the hatch moment

Variation in the hatch moment

Factors influencing the moment of hatching

(Too) early hatching: (Too) late hatching:

• Pre-warming temperature too high. • Eggs were set too early, and incubated too long. • Hot spots in the incubator. • Seasonal influences that cause temperature fluctuations in the incubation environment. • Too many fertile eggs in the incubator, without an adapted incubation program. • Egg size (too small). • Breed/line. • SPIDES. If the eggs have been incubated for a few hours, development has been briefly arrested. This period must be deducted from the incubation period. There can also be wide temperature differences in the hatcher. This affects the hatching time, as well as chick quality. Newly hatched chicks can become too hot or cold. The right stack is clearly too warm. And especially at the top, because the heat rises. In this case, the heat could not escape, because the ventilation openings in the partitions were blocked by condensation and down.

Temperatures being too low at the beginning of the incubation process are often the cause of delayed • Setting the eggs too late. hatching. Too high temperatures at the end acceler- • Incorrect incubation ate the hatching process, to the point where the • temperatures (too low). Incorrect ventilation (too much embryos suffer too much damage. And this actually cold air). leads to delayed hatching again, or embryo mortal- • Seasonal influences that cause ity in the egg. temperature fluctuations in the incubation environment. Variation in embryo temperatures is the most • Egg storage time too long. important factor affecting variation in hatch • Egg storage temperature too moment. This is particularly the case during the • low. Incorrect setting pattern in the first week of incubation, as a result of lack of uni- multi-stage incubator. formity in egg temperature during the start of the • Disease or fertility problems. incubation process. Embryo temperature in cold • Egg size (too large), without an adapted incubation program. parts of the incubator is low and the eggs there will hatch later, whereas embryos in warmer parts of the incubator will hatch earlier. copyright protected

Often, there is a fluff corridor at the rear of the hatcher. The negative air pressure draws air through the corridor. The fluff/dust is collected in sacks or the corridor itself. Residues are left behind after the hatcher baskets have been removed: eggshells, first droppings (meconium), fluff. There are useful signals here too. Hatchery managers often pay attention to fluff. A lot of fluff means the chicks have dried off well.