Dying Immediately Before Hatching
After having most hens hatching on the 13th day of incubation, I recently had about a week of roller and border chicks not hatching. while Stafford and Colorbred continued to hatch on the 13th day but not a roller or border would hatch.
Normally, if an fertile egg does not hatch by noon of the 14th day, I check to see if they are alive by floating the egg in a dish of warm water. If the chick is alive the egg will jiggle. Then I move the live eggs to another hen and the eggs will hatch sometimes in a hour or two but certainly by the next morning. This time, however, it did not work, even though I moved them at noon on the 14th day, I just could not get them to hatch.
Every egg that fails to develop or that dies should be necropsied. Early embryonic mortality is common with improper incubation temperature, jarring, inbreeding and chromosomal abnormalities. Deaths at the end of incubation are usually associated with hatching, and the stressful period of switching to pulmonary respiration when the chick must start breathing air. Factors including improper incubation humidity, temperature and turning are leading causes of late embryonic death.
Opening the egg over the air cell, I saw chick after chick dying late in embryonic development, in good position but it had failed to pip through the membrane to breathe air. Its beak was right up against the membrane but it couldn't break it.
Since the transferring of live eggs to other hot hens failed, I had ruled out the hens incubation temperature as the cause for eggs not hatching. When I checked on humidity, I learned that we were experiencing extremely low humidity levels of 19%. And as I compared the roller and border eggs to the Stafford and Colorbred eggs. The shells were much more dense on the Stafford and Colorbred eggs making them resistant to drying out and toughing the membrane as a result of the low humidity! The absence of Spring rains, which are so normal for Kansas, had affected my roller and border hatching. The good news is that we got some rain, now its raining two or three times a week! I simply increased the frequency and amount of egg shell fed to improve the shell, and normal hatching has resumed!
Be sure and read the comment from Shawn Bartlett to this post! Thanks so Much for the Idea!!
Lesson: If something goes wrong do not jump in and change things, two wrongs will not make it right, rather look for the obvious cause and make only minor adjustments as indicated!