Is movement of the egg in water a good way to distinguish alive from dead embryos?

[superdood56]

Hello everyone,

I posted here a few months ago with some questions about my science experiment. Briefly, I am experimenting with Japanese quail eggs (Coturnix coturnix) to determine the temperature at which they die (I know, it's sad) and have been using the Buddy Heart Rate monitor to distinguish those eggs that are alive from those that are dead. On day 10 of incubation I take all the eggs (around 25) that are confirmed alive by the Buddy and expose them to heat. I then check for the presence or absence of a heart rate in all 25 eggs each day thereafter until day 15 of incubation. On day 15 they are all frozen and dissected for further measurements.

However, the Buddy Heart Rate monitor is giving me inconsistent results after the heat exposure - sometimes I have to rotate the egg 5-8 times for the infrared sensors to detect a heart rate, and sometimes the display will show non-rhythmic activity without a heart rate. Additionally, sometimes an egg does not have a heart rate (e.g. on day 12) but then the next day that same egg is showing a heart rate. Given the inconsistency I have been searching for an alternative noninvasive method to distinguish those eggs that are alive from those that are dead.

I placed a few eggs into a deep water bowl today and observed movement in some eggs and lack of movement in others (I'm assuming movement = alive and no movement = dead). Is this an effective way to tell if an egg died during development as a result of the heat? If this is effective, does anyone have a link to a scientific article confirming this? Or are there other methods that I am not aware of? To clarify, all 25 eggs were reliably confirmed alive through candling and the heart rate monitor from days 6-10... From days 11-15 there have been inconsistent readings on the heart rate monitor, presumably as a result of the heat exposure.

Thank you for your help in advance. I can also clarify any misunderstandings.

 

[oregonkat]

No, is the short answer. IMHO this method should only be used when eggs are several days past their due hatch date and even then it can be misleading. The chick, if alive, may be 'sleeping' and not mobile at that particular moment and not moving. There are many folks on here who have considered an embryo dead only to find it alive upon opening the egg. Immersing the eggs in water (I assume this is the same with quail eggs) risks allowing bacterial infection by washing the bloom off the egg. This of course, is a point that becomes moot as the eggs are past the point of being too badly affected if still alive and on the point of hatch. If done mid hatch, however, then the risk is significantly high. This is all IMHO so other folks may disagree.