Look for publications of Kaltofen and El Jack in the 1970's.

Dear Monsuru

We m​ust mention to related factor is humidity during storage of the eggs or during incubation, the change in the temperature will have different effects in different humidity percent.

hi

as I know that we m​ust mention to related factor is humidity during storage of the eggs or during incubation,and the time and place with the change in the temperature will have different effects in different humidity percent.

Mnay factors have clear influence on the hatchability of eggs. Numerous of these are important before the eggs are placed in the incubator. example:

breeder flock nutrition , health, , breed and age , finally flock management, all of these can result in tremendous variation in hatchability. Equally important is the microenvironment surrounding the eggs before incubation, After setting in the incubator, temperature, turning, humidity, ventilation in the incubators and incubator rooms, sanitation, and general hatchery management are all critical factors to ensure embryonic survival and hatchability.

In addition to egg collection, storage, and handling must be optimum to maintain embryonic viability before and during incubation.

I agree with Alaa Abed's suggestion. In addition, may I add that the number of times the hatching eggs are collected from the poultry house, stored in the storage room, time and duration of fumigation, number of days eggs are stored before the eggs are set for incubation, size of air cell, shell strength, age of the breeder flocks and their nutrition and production status- all will have a say, on the hatchability when the environmental temp. is high.

lnathgubbi

Some factors related to breeder flocks itself such as age of flock, good nutrition with good vitamins supplements, good biosecurity, number of eggs collection/day, eggs fumigation, storage of eggs, duration of eggs storage before incubation and transmission of eggs.

Also another factors related to incubator such as humidity, temperature, ventilation, turning and sanitation.

Greetings! Stress is a protective immune reaction of the body aimed at preserving, regulating and maintaining homeostasis in the organism of chickens. And of course, it is necessary to fight not with stress, but with its possible pathophysiological consequences of the General adaptation syndrome. It's not right, if when say that need to deal with stress. Otherwise it turns out that we are fighting the natural immune system of the bird's body.

It is necessary to prevent possible pathophysiological consequences of the general adaptation syndrome. But do not fight with the general adaptation syndrome as such.

It is desirable to control the level of glucocorticoids in peripheral blood from parents.

In addition to all they said I can say that there are some ecological and social factors that can affect egg hatchability. for more infos go to the below link

https://sora.unm.edu/sites/default/files/journals/auk/v099n03/p0526-p0536.pdf

Semen quality also is a factor especially if AI is practiced. Breeding males are affected equally as are hens and therefore, frequency and dose of AI may also need to be increased.

Heat stress negatively impact on the hatchability such as:

1- high ambient temperature lead to increase panting and consequently, disrupt acid-base balance which affects the shell quality

2- reduction in the egg production related to low egg fertile

3- reduction in the semen quality of males

4- reduction in the egg quality (yolk، albumen and shell formations) due to decrease feed consumption

Other factors that related with hatching eggs itself and storage conditions cn be avoided.

Thanks

Thank you all for the answers. i really acknowledge your contributions to knowledge.

yes, because heat stress causes decrease in egg shell quality that is the major factor affect on hatchability

I would like to note. I believe that, dont heat stress causes decrease in egg, but those pathophysiological consequences caused by super-physiological temperatures. I repeat and emphasize. Stress-reaction initially, in the organism of the animal, is aimed at restoring homeostasis.

Unfortunately, often, many authors confuse the stress response - protective reaction of the organism and the pathophysiological consequences of stress reactions that may arise (or may not !!!), provided there is a shortage of resources in the animal's organism. Therefore, it is necessary to prevent the pathophysiological consequences of stress - by increasing the trophic resources in the organism. And do not fight the stress response, in fact, so only we oppress immunity, and not help the body to restore homeostasis.

Heat stress has negative effects on spermes activity in males , subsequently weak embryo.

You should study skeletal structure of hatched chicks and teratology.

Dear Monsuru

The heat stress affect the food intake of the birds and result the dropping in the egg production of the layer hens or breeder hens, besides deficiency in the nutrient elements content in the hatching eggs which affect the embryonic development and hatchability.

Good Luck

Dear respected Monsuru Oladimeji Abioja,

Yes, heat stress affects hatchability of poultry birds. The division and multiplication of the cells of the embryo in the egg shell come as a result of the response to environmental stress in which heat stress is included and plays a crucial roles in physiological change in the embryo. When the heat stress is extreme high it leads to rapid and abnormal growth which can eventually results to the death of the embryo.

Best regards

Kifilideen

Dear respected Monsuru Oladimeji Abioja,

When the heat stress is extreme low it leads to slow growth (slow cell division and multiplication) of the embryo which on the long run can inhibit the physiological change and metabolic activities of embryo which can eventually results to the death of the embryo.

Best regards

Kifilideen

Dear respected Monsuru Oladimeji Abioja,

The temperature is the major parameter used to monitor heat stress in an egg incubator. To have high hatchability of the embryo in the egg incubator the recommended range of temperature is between 36° C and 39 ° C. The heat presents in the incubator at this temperature range can not have adverse effect on the successful hatchability of the embryo and also safe for the growth of the embryo in the egg shell. Going beyond or below this range of temperature would affect the hatchability and would low the hatching value.

Best regards.

Kifilideen.

I following the best answer.