How can I tell if eggs are late quitters?

[duckncover]

I have 8 serama (possibly japanese bantam mixes since some people aren't honest about what they are selling) eggs entering day 21. I feel as though these eggs are not filled out properly and I haven't seen much movement. Is there anyway to know if they are late quitters? Some looked more promising than others when I candled. I got 4 chicks from 7 eggs last time from the same birds. I also have a large number of coturnix and button quail eggs hatching tomorrow as well in a separate incubator. Third incubator has more serama eggs in early development and a few california quail eggs that I'm testing the fertility of. If this is the case that I'm getting late quitters what could I be doing wrong to be getting this outcome and how do I correct it?

 

[007Sean]

Only after the hatching date has passed, you can crack them open and inspect the embryo for the stage of development. There are plenty of picture charts on the web you can use as a guide in determining at what stage they ceased to develop.

There's a whole host of reasons for termination of development. When hatching large quantities of eggs, a general rule is, 1/3 quit early, 1/3 quit mid-way, and 1/3 quit late in the incubation process. Some may be genetics, ie; lethal genes. Some may be from bacteria entering the shell. Some from the chromosomes not matching up properly. Some don't receive the right signals, hormones, missing essential vitamins or nutrients, the DNA and RNA sequencing may have gotten out of sync...and many more reasons than I can think of right now.

It may or may not have to do with the incubator or how you operate your incubator. Just too many factors to give you a definitive answer as to why they quit developing.

 

[duckncover]

I think I read that Japanese and serama have that lethal gene. So we will see. The hatch tracking app I am using doesn't allow me to set a time. Only the date. Whatever time it is when I create the batch is the time it says they were put in. So they may still have a day. I was not impressed when I candled them. I expected the eggs to be dark and full. Most had a lot of area that was see through and I didn't see much Veins and no movement on most.