Late Death

[larajmd]

What causes late death?
recently incubated of chicken eggs of mixed breeds. All brought from online suppliers
activity inside the eggs ceased a few days before the due date
I had 24 eggs of which only 3 hatched.
I was brave enough to open up the eggs and the chicks were very well developed

what went wrong

 

[ChickenCanoe]

A million things.

specifically from the website - natureform hatch systems
http://www.natureform.com/kb/index.php?article=1011&o=save

Dead embryos; >18 days of incubation. Causes:

1. Improper incubator temperature, humidity, turning, ventilation.
2. Improper hatcher temperature, humidity, ventilation.
3. Contamination, especially from molds (aspergillis, etc.).
4. Fumigation too severe or too prolonged.
5. Eggs chilled in transfer, or transferred too late.
6. Broken shell -- pre-set, during incubation, or at transfer.
7. Nutritional deficiencies -- vitamin D, vitamin A, folic acid, or pantothenic acid, riboflavin, vitamin E, selenium, vitamin K, biotin, thiamin, vitamin B12, calcium, phosphorus, manganese, or linoleic acid.
8. Embryonic malposition; embryo fails to move into proper hatching position (see #21).
9. Embryological development accident. Failure to change to lung respiration and all intra-embryonic circulation, and/or to retract the intestinal loops and yolk sac. These and other changes are critical at this time.
10. Heredity -- lethal genes, chromosome abnormalities.
11. Twinning.
12. Hatcher opened too much during pipping and hatching.
13. Poor shell quality.
14. Breeder diseases.

Not pipped. Full-term embryo, large yolk sac; yolk sac may not be fully enclosed by abdominal wall, may have residual albumen. Causes:

1. Inadequate turning, resulting in decreased embryonic membrane development and nutrient absorption.
2. Humidity too high during incubation or after transfer.
3. Incubator temperature too low.
4. Hatcher temperature too high.
5. Eggs chilled (e.g., at transfer).
6. Nutritional deficiencies.
7. Heredity.
8. Embryological development accident.
9. Breeder diseases.
10. Inadequate ventilation.
11. Prolonged egg storage.

 

[orange tomato]

Were the ones that hatched in the middle of your incubator? If so, could have something to do with the temperature setting.
Was someone opening the incubator a lot to check in them? If you do this too much, the humidity levels drop and can this can also cause that problem. Humidity and temperature are very important all through the process. It could be something else, but that is my best guess.