Petersime and layer breeding company Hy-Line do Brasil have joined forces to investigate the benefits of using heat treatment for layer eggs stored for 6 to 8 days. In a series of comparative trials using the BioStreamer™ Re-Store to apply the SPIDES process for layers, they have tested 121,500 eggs. The first results are spectacular. 

Heat treatment before incubation

Heat treatment of stored eggs has been around for a long time. The Re-Store process, also known as ‘Short Periods of Incubation During Egg Storage’ (SPIDES), has been up and running for several years now. Inspired by the mother hen brooding on a clutch of eggs, this technology ensures the eggs are brought to a more uniform stage of early embryonic development before incubation starts. For example, the use of SPIDES in turkey incubation and broiler incubation has already been proven very successful.


Research set-up

Petersime and Hy-Line do Brasil have set up a series of comparative trials to investigate to what extent heat treatment benefits stored layer eggs. In the first phase, they studied a total of 121,500 eggs that were stored for 6 to 8 days: 

  • 54 hatches in total.
  • Eggs from both young, middle and old flocks, and of three different breeds.
  • 50% of all eggs were incubated with Re-Store treatment at three different time intervals. They were treated for an average of 12 hours per cycle, on the fifth day of storage.
  • The other 50% were incubated without treatment at three different time intervals (control eggs). 
  • The researchers consistently followed the standard program on a fully loaded BioStreamer™ Re-Store incubator. 
layer hatchery; trials; heat treatment; SPIDES
Thanks to the unique OvoScan™ technology, Petersime’s Re-Store incubator guarantees a controlled, gradual and precise heating and cooling of the eggs, ensuring highly consistent results.

Significant results

Number of culls decreased with 0.91% in total

The number of dead chicks or chicks with severe problems decreased significantly. In eggs treated with Re-Store, the researchers measured 1.9% culls versus 2.8% in eggs that did not get the Re-Store treatment

2.12% better hatch results

The results went up from 40% to 42.12% hatched eggs (this applies to 50%, because only females are counted). 

Early death decreased with 0.9% in total

The most important reason for this raise in hatchability is the fact that early death decreased with Re-Store treatment. 'Early death' means that embryos died in the first 7 days of the incubation cycle. After break-out analysis, eggs without Re-Store showed 5.2% of early deaths versus 4.3% in eggs with Re-Store

1.5% better uniformity with Re-Store treatment

The researchers weighed a sample of 100 chicks per treatment. The percentage of chicks that were within the range of ±10% around the average weight are considered 'uniform'. Ideally, at least 80% of chicks should be within that range. For eggs with Re-Store treatment, the uniformity was 86.2% versus 84.7% for the control eggs. 

To give you an idea, the gains for a hatchery with a monthly production of 3,000,000 day-olds would be: 

  • Hatch gain: + 2.12% = 63,600 more chicks per month
  • Culls gain: - 0.91% = 27,300 less culls per month



Comparative trials proved that a heat treatment with the BioStreamer™ Re-Store on short-stored layer eggs (6 to 8 days) improved both hatch and post-hatch performance. With the aim to further optimize incubation programs, the research team at Petersime and Hy-Line do Brasil will continue to study the benefits of restoring longer-stored eggs from different lines, breeds and flock ages. 


BioStreamer™ is Petersime’s previous generation of single-stage incubators. Our engineers use innovative research and technology every day to constantly develop new solutions. Read more about our latest generation of intelligent single-stage incubators, X-Streamer™

About the author
Petersime Bruno Machado Sqr
Bruno Machado Global Incubation Consultant

As a dedicated poultry business specialist, Bruno Machado holds a degree in Animal Science, an MBA in Poultry and an MBA in Business Management. He has gained deep expertise in the poultry industry, e.g. in the role of hatchery manager. In his capacity as Global Incubation Consultant at Petersime, his work covers research projects, field trials as well as customer training and support.

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