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Incubation ProceduresBreeding Challenges

Useful Information: Breeders’ ResourcesEgg Incubation – pdf format … Incubation Information (html)

Unsuccessful hatches can be caused by infertile eggs or embryo mortality. Each of these conditions can be diagnosed by Candling Eggs.

It is important to examine eggs that do not hatch to estimate whether infertility or embryo death is the basis for hatch failure. Also spoiling infertile eggs and those containing dead embryo could contaminate viable eggs, thus decreasing hatching success.


Relevant Resources:



Incubated Eggs won’t hatch – Potential Causes and Solutions


  • No chicks hatched

Possible Causes

  • Infertility
  • Infection
  • Sick hen
  • Considerably incorrect incubator settings


  • Candle the eggs to assess fertility and condition
  • Disinfect the incubator
  • Verify the settings of the incubator — particularly the temperature.
  • Ensure that the incubator is placed in a stable environment. Ideally, incubators should be placed in a room where the temperature remains in the 70s. However, most incubators (including the Mini Advance) can work with temperature variations from 60 – 80 degrees Fahrenheit. Hatchability may still occur at temperatures as low as 60 or as high as 90 degrees. However, if the temperature drops to below 60 or goes above 90 degrees, no incubator would be able to maintain the correct temperature inside the unit to ensure hatching – this includes the expensive professional incubators. Incubators should be placed in an area where there is no direct sun exposure (sunrays hitting the unit will increase the “ambient” temperature immediately around – and therefore inside – the unit significantly; nor should the incubator be placed in an area with drafts (from windows, doors or air conditioning vents).


  • Chicks hatch earlier than expected
  • Deformed chicks hatch

Possible Causes

  • Incubation temperature too high


  • Reduce the incubation temperature somewhat (0.5° C)


  • Chicks hatch later than expected

Possible Causes

  • Incubation temperature too low


  • Increase the incubation temperature somewhat (0.5° C)


  • Hatching times far apart

Possible Causes

  • Different development phases based on differing storage periods or fluctuations of the incubation temperature


  • Limit the time storage periods of the eggs
  • Ensure a steady incubation period — avoid direct sun exposure which would increase the temperature inside the incubator; ensure steady room temperature


  • Chick death at late stage of development

Possible Causes

  • Incorrect humidity levels — probably too high


  • Reduce the humidity inside the incubator somewhat


  • Generally poor results

Possible Causes

  • Incorrect incubation settings
  • Poor health of the parents
  • Insufficient turning of the eggs


  • Correct the incubation settings
  • Improve the health of the parents
  • Analyze the weight loss of the eggs to assess the optimal humidity levels
  • Turn eggs more frequently (if automatic egg turning – ensure it’s functioning)

Nutritional Deficiencies:

Depending on the degree of malnutrition, either death or physical symptoms will occur. Please refer to the below:

Vitamin A: Death at about 48 hours of incubation from failure to develop the circulatory system; abnormalities of kidneys, eyes and skeleton

Vitamin D: Death at about 18 or 19 days of incubation, with malpositions, soft bones, and with a defectiveupper beak prominent.

Vitamin E: Early death at about 84 to 96 hours of incubation, with hemorrhaging and circulatory failure(implicated with selenium).

Thiamin: High embryonic mortality during emergence but no obvious symptoms other than polyneuritis inthose that survive.

Riboflavin (Vitamin B2): Mortality peaks at 60 hours, 14 days, and 20 days of incubation, with peaks prominent early asdeficiency becomes severe. Altered limb and beak development, dwarfism and clubbing ofdown are defects expressed by embryo.

Niacin: Embryo readily synthesizes sufficient niacin from tryptophan. Various bone and beak malformationsoccur when certain antagonists are administered during incubation.

Biotin: High death rate at 19 days to 21 days of incubation, parrot beak, chondrodystrophy, severalskeletal deformities and webbing between the toes. Perosis.

Pantothenic acid: Deaths appear around 14 days of incubation, although marginal levels may delay problems untilemergence. Variable subcutaneous hemorrhaging and edema; wirey down in poults.

Pyridoxine: Early embryonic mortality based on antivitamin use.

Folic acid: Mortality at about 20 days of incubation. The dead generally appear normal, but many havebent tibiotarsus (long leg bone), syndactyly (fused toes) and beak malformations. In poults, mortality at 26 days to 28days of incubation with abnormalities of extremities and circulatory system.

Vitamin B12 : Mortality at about 20 days of incubation, with atrophy of legs, edema, hemorrhaging, fattyorgans, and head between thighs malposition.

Manganese : Deaths peak prior to emergence. Chondrodystrophy, dwarfism, long bone shortening, headmalformations, edema, and abnormal feathering are prominent. Perosis.

Zinc: Deaths prior to emergence, and the appearance of rumplessness, depletion of vertebral column,eyes underdeveloped and limbs missing.

Iodine : Prolongation of hatching time, reduced thyroid size, and incomplete abdominal closure.

Iron: Low hematocrit; low blood hemoglobin; poor extra-embryonic circulation in candled eggs.

Source / Reference: gallus.tamu.edu/Extensionpublications/b6092.pdf


Eier: Küken schlüpfen nicht oder sterben in der Schale



The below test pinpoints the incubation stage of the egg, if unknown.

  • If the eggs are cool to touch, incubation has either not commenced yet or the eggs have been abandoned.
  • If the eggs are warm, one can assess the stage of development by placing the eggs into a pail of water. Please refer to below illustration.

NOTE: This is a popular science project and quite accurate, but not recommended for breeders, as any significant temperature change the egg is exposed to is likely to hurt the developing chick.


Egg Flotation Chart


In-depth information on egg incubation, step-by-step instruction – important technical specifications to follow (pdf format)


Species Research by Sibylle Johnson


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