The lowest EST readings are often found at the start of incubation
in multistage incubators, whereas high EST readings are
not uncommon in both single-stage and multistage incubators
in the latter part of incubation. Large EST fluctuations
have an obvious impact on hatchability and chick
quality (Lourens, 2001), but so do slight deviations of less than 1°C from 37.8°C EST