Temperature is one of the most critical needs for embryo development during incubation.
Too high it might damage your embryo and affect the chick quality; too low your embryos might not even develop and also affect the quality of your hatched chicks resulting in weak chicks.
It is very important to monitor and control your temperatures to ensure optimal conditions for embryo development are met. The ideal temperature for most poultry eggs typically ranges between 37-38 degrees Celsius.
Temperature fluctuations can result into a big disaster with total embryo mortality or no development at all. The temperature in the incubator is influenced by the air temperature that is circulated and produced by your incubator heaters and also the eggshell temperature that is given off by the developing embryo over time.
To achieve optimal conditions, it is important to take both temperatures into consideration when monitoring and setting your incubator.