(normally this is a period of relatively low embryonic death)
Causes:
- Incubator temperature too high.
- Infected embryos either by infection from hens, or especially, by external microbial contamination through shell.
- Lack of ventilation.
Correction:
- Check accuracy of thermometer. Operate incubator at proper temperature.
- Provide adequate ventilation of the incubator room and proper openings of the incubator ventilators.
