![]() ![]() ![]() The reason for this is not totally clear. Excessive loss of water during long-term storage has generally been reported to be detrimental for hatchability. The advise to decrease the storage temperature if the storage period increases, is to slow down the loss of carbon dioxide from the egg and to slow down the development of the embryo. ![]() Thus, a change in albumen quality during storage seem to be necessary to protect and support embryo development. A decrease in albumen height is necessary to meet the oxygen requirements of the embryo during storage and early incubation. This difference might be necessary to facilitate certain transport functions across the albumen and yolk to and from the embryo. Due to the relatively high increase of albumen pH during storage, a pH difference arises between yolk and albumen. One of the positive effects of the increase in albumen pH is the protection of the embryo against a bacterial invasion. The loss of carbon dioxide to the environment and thus changes in albumen pH and albumen height is dependent on length of storage period, storage temperature, transport of carbon dioxide thought the albumen, conductance of the eggshell and eggshell membranes and the concentration of the carbon dioxide outside the egg. The yolk remains slightly acid during storage, at a pH around 6.5. Carbon dioxide is released from the egg, resulting in an increase in albumen pH from 7.6 at oviposition to a pH of 9 to 9.5 within 4 days of storage and a decrease in albumen height. If a clutch of eggs is ended incubation starts.Īfter oviposition, an egg cools down to ambient temperature and an air cell is formed due to evaporation of water through pores in the shell. While the egg is laid the other eggs in the nest are warmed for a short period. Once a day the hen comes to the nest and lays an egg. The eggs are laid in a nest and there is no regulation of temperature or relative humidity. Consequently an interesting question is: what is the difference between storage in nature and storage before artificial incubation? Storage of eggs in nature seems to be simple. Nevertheless the detrimental effects of prolonged storage periods in nature seem to be less than in artificial incubation. In nature, storage periods of more than 7 days are common as well, because a hen starts incubation when all eggs of a clutch are laid. It is common known that eggs of young breeder flocks are better suitable for prolonged storage periods than eggs of older breeder flocks, because albumen quality in eggs of younger breeder flocks is higher. In practice, longer storage periods are sometimes unavoidable. A short storage period of 3 to 4 days seems to be necessary for a good hatchability. On the other hand it is also known that early embryonic mortality increases if eggs are set on day of oviposition. Despite of the climate regulation in the storage room it is commonly known that hatchability declines if the storage period is longer than 7 days. To prevent water loss from the eggs, the relative humidity in the storage room is kept between 70 and 80%. If the storage period is less than 7 days a storage temperature of 16 to 18☌ is advised and if the storage period is longer, a temperature of 10-12☌ is mostly recommended. At both locations eggs are stored in a storage room, where the temperature and relative humidity is controlled. After arrival at the hatchery, it normally takes a few days before the eggs are set in the incubators. Eggs are stored at the breeder farm before they are transported to the hatchery. Condensation of eggs should be avoided at all times to prevent bacterial contamination as much as possible!ĭue to variable market demands for day old chicks in the poultry industry it is common that hatching eggs are stored before incubation starts. During egg storage, egg contents change and the speed of change largely depends on the outside conditions. ![]()
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