Research project Towards a higher efficiency by sustainable extension of the laying cycle

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Sam De Campeneere

Sam De Campeneere

Scientific director, ILVO Animal Sciences


General introduction

The "Leglanger" (longer-lay) project is built on the previous "Long-lay" project. The goal remains to responsibly extend the production cycle to 100 weeks without molt, which now ends by 75- 80 weeks. The genetic potential is there, as proven by previous research. Extension of the laying cycle would improve the sustainability as well as the profitability of the sector. The first limiting factor is eggshell quality, but in this project we investigated which other factors like health (FLHS, osteoporosis), welfare (feather pecking), management and nutritional (Ca- metabolism) can detract fromo or contribute to this goal.

Research approach

We determined all the risk factors that contribute to an early production cycle stop. Measures and guidelines to address these were then tested. In a second phase, the nutrient metabolism and nutrient requirements of older laying hens were examined. This knowledge has been nearly non-existent, while it is essential for the Longer-Lay goal to support the hens from day 0 in extending their laying cycle. Based on these findings a calculation tool is developed to determine the optimal productive age of laying hens. All acquired knowledge was offered to all those involved in the sector through various media (seminars, webinars, articles).


Determining the nutritional needs of older laying hens will result in a lower environmental impact: it emplies more efficient use of feed and water, a reduction of waste material, lower nitrogen emissions and ultimately improved sustainability and higher profitability of Flemish laying hen farms. With the online calculation tool, farmers can determine the optimal productive age of laying hens on their farm themselves. In addition to livestock farmers, feed companies and breeding organizations were also provided with tools to enable the extension of the laying cycle. By assisting poultry farms individually and providing an online platform poultry farmers were encouraged to implement these innovations on their farms.