1. Daily changes in embryonic heart rate (HR) of emu were determined non-in
vasively at 36 degrees C by acoustocardiography (ACG) during the last 30% o
f artificial incubation (predicted incubation time is 50 d).
2. The pattern of daily changes in mean HR of hatched embryos decreased fro
m about 175 bpm to about 140 bpm towards the end of incubation.
3. The mean HR at 80% of incubation (ca. 170 bpm) was close to the value pr
edicted from an allometric equation reported previously for precocial domes
ticated birds.
4. ACG could measure embryonic HR even during the external pipping period.
5. If the artificial external pipping procedure is timed correctly after in
ternal pipping, it might aid the embryos in hatching. However, further inve
stigation into this aspect is needed.