What is the best temperature for storing eggs?

Most hatchery planners aim to keep egg age under 7 days at set. However, even in broiler hatcheries this is not always easy, or even possible. You may need to build up numbers so that a single broiler unit can be filled using eggs from only one breeder flock, order sizes may not be exactly even day to day or there may be a general slowdown in the market for seasonal or other reasons. Most advice on egg storage conditions suggests that the temperature should be adjusted
dynamically depending on the average egg age. However, in practice the advice is seen as too complicated and is rarely followed. Consequently, in many operations egg storage temperature stays firmly at 17-18°C, no matter what the egg age.

In fact, the best advice is that egg store temperature should always be adjusted downwards to be optimal for the oldest eggs. Fresh eggs hatch just as well stored at colder temperatures, but older eggs suffer badly if the egg store is held too
warm. The only thing you need to watch out for is the possibility of condensation when moving eggs from the cold egg store into the setter rooms.

Keeping eggs which need to be stored for longer at a lower temperature slows down the physical deterioration to the albumen and yolk membranes which are needed to support the best hatchability. The embryo will also be affected by both storage time and storage temperature, and colder storage slows down the rate of deterioration in the embryo as well. A recent collaborative study between Aviagen and Ankara University investigated the effect of storage temperature on hatchability in eggs stored for 14 days, as part of a larger investigation into how SPIDES treatments interacted with storage temperatures. In the study, covering young, prime and old grandparent flocks, hatchability was much better when 14-day-old eggs were stored at 15°C rather than 18°C. More unexpectedly, eggs stored at 12°C hatched no better than those stored at 15°C. The hatchery where the trials were done is unusual in having three separately controlled egg stores, so it was possible to run comparisons of the three storage temperatures simultaneously which gave a very robust
comparison of the three storage temperatures. The trial was repeated over four batches of eggs, from young, prime and old flocks.

The graph below shows how eggs stored at 18°C hatched worse than those stored at 15°C by an average of 4.4% over 4 comparisons covering young, prime and older flock ages. In contrast, when hatch of eggs stored at 12°C was compared with hatch of eggs stored at 15°C, there was no overall improvement.

Our conclusion from these trials was that unless eggs are only being set when very fresh (no more than 4 days old) it is probably better to run egg stores at 15°C rather than 18°C. When setting eggs within the hatchery condensation is unlikely to be a problem following storage at 15°C, but if you are worried check the dew point table in Investigating Hatchery Practice to make sure.

First published in International Hatchery Practice