Humidity during storage
ec
te
d
LOOK-THINK-ACT
pr ot
Maintaining 75% (±5%) relative humidity in the storage room is sometimes suggested as a way of avoiding excessive moisture loss in the eggs. But remember that condensation can easily form on the fresh eggs (sweating). It is a good idea to calculate the dew point, at which condensation can occur. You need to know the temperature and humidity of the air and use an internet calculation tool (available on www. hatchability.com). Too much moisture loss only occurs when eggs are stored for an extremely long period. During the incubation process, the embryos appear to be able to compensate for this moisture loss during storage. Using humidifiers in storage rooms is not recommended due to the risk of the eggs becoming wet. This creates a favourable climate for bacterial and fungal development. Make sure a cooling fan is not pointed directly at the eggs. The eggs will then not be uniform in temperature. This causes major changes in embryonic development, resulting in a wider hatch window at the end. So ensure indirect ventilation and regularly check the temperature distribution in the storage room.
There is a lot of traffic through this door in the storage room. It is opened and closed frequently. This creates an uneven temperature in the storage room and warm, moist outside air can flow into it. Prevent staff from entering the storage room too often, and provide a lock. And install a door closer to ensure the door always closes tightly. Also pay close attention to where you place the sensor and the air conditioning units with respect to the door.
co
py
rig
ht
Why is this a problem?
Incubator on the breeder farm? It is smart to set up a small incubator on a breeder farm. For example, you can place 30 eggs from different parts of the poultry house (using cracked eggs is fine). After three periods of 24 hours you will have a good idea of the average fertility of a house. The farm manager is also armed with good arguments for ‘defending’ himself or herself in the event of deviating results. Good communication between the breeder and the hatchery will lead to a higher efficiency of hatching eggs. A trial incubation is often done at 25% production, and at 50% production. This will provide a good prediction of the fertilisation rates and the expected hatching results
4. E gg h a n d l i n g a n d q u al i ty
59
