when using a Still Air incubator (no fan) at 102º F. The reason for different temperatures is that with a fan model the circulating air warms all around the egg while still air temperatures are warmer at the top of the egg than at the bottom. The temperature is measured at the level where the embryos develop (at the top of the HORIZONTAL egg).
NOTE: If the eggs are in vertical position, elevate the thermometer just below the top of the egg. The temperature is measured at the level where the embryos develop (at the top of the egg). Never allow the thermometer to touch the eggs or incubator because incorrect readings can result.
A high temperature tends to produce early hatches. A consistently cooler temperature tends to increase incubation times and produce weakened chicks. In both cases the total chicks hatched will be reduced. Prepare your incubator and run it for several days before adding eggs, to be positive you are maintaining correct incubation temperature.
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