I have 17 eggs. After they were laid, they all had embryos that were at the top of the egg. They are being incubated at 83 degrees. There is adequate humidity in the incubator. After a couple of days, one had no embryo, and then another. There are now 3 eggs without any veins or an embryo. It has been 10 days since they were laid. Can anyone tell me what is happening and why?