The effects of exposing Dandarawi fertile eggs to warm air before incubation on embryonic development, mortality and hatchability were studied. Seven hundred and fifty fertile eggs were used in this trial. Eggs were collected and stored at 16ºC for five days. Eggs were taken out the storage room and set for 12 hours in ambient air temperature (28ºC). Individual egg weights were recorded, then eggs were divided into five treatment groups (n=150 of each group). The first group (G1) was left for an additional 24 hours at room temperature and served as control. While, the other four groups (G2, G3, G4 and G5) were exposed to a temperature of (38-38.2ºC) for the respective durations of 6, 8, 10 and 12 hours, respectively, then to the ambient temperature (28ºC). After the 36 hours from taking the eggs out the storage room, all groups were set in the incubator. A sample of eggs from each group (n= 12 of each once) was cracked to record embryos’ relative weights at 6, 12 and 18 d of incubation.
Eggs exposed (P<0.05) to warm air prior to incubation had higher embryos weights at 6 and 12 d of incubation compared to the control. At hatch, no significant differences in hatchling weights were observed. Warming eggs before incubation decreased embryonic mortality, pepping chicks and improved hatchability (P<0.05).
In conclusion the pre-incubation warming for 10 or 12 hrs reduces embryonic mortality, pepping chicks and improves hatchability in Dandarawi eggs.