In aviary systems for laying hens, it is important to provide suitable nest access platforms in front of the nests, allowing hens to reach and explore each of the nests easily, according to Karin Stämpfli and colleagues at the Swiss Federal Veterinary Office, Centre for Proper Housing: Poultry and Rabbits in Zollikofen.

In their paper in Poultry Science recently, they explained that this access platform is needed to achieve good nest acceptance by the hens and thereby prevent mislaid eggs.

From their results, they concluded that grids rather than perches provide for improved nesting behaviour.

In the present experiment, they examined the behaviour of hens using two different nest access platforms - a plastic grid and two wooden perches. The nests were placed on both sides of the aviary rack (corridor side and outdoor side), either integrated into the aviary rack itself (integrated nest; IN) or placed on the walls of the pens (wall nest; WN), resulting in a 2×2 factorial design.

A total of 4,500 white laying hens were housed in 20 test pens.

The eggs in the nests and mislaid eggs were collected daily, and the behaviour of hens on the nest accesses was filmed during weeks 25 and 26, using focal observation and scan sampling methods.

More balancing, body contact and agonistic interactions were expected for nests with perches, whereas more walking and nest inspections were expected for nests with grids, the researcher hypothesised.

There were more mislaid eggs and balancing found in pens equipped with nests with wooden perches. More agonistic interactions and balancing, less standing and a longer duration of nest inspection were found with the WN compared with the IN.

Interactions between platform design and position of the nests were found for duration of nest visits, body contact and walking, with the highest amount for WN equipped with plastic grids.

Nests on the corridor side were favoured by the hens.

Nest-related behaviour, such as nest inspection, standing and walking, decreased over time as did the number of hens on the nest accesses, whereas sitting increased.

These results indicate that the hens had more difficulties in gripping the perches as designed, concluded Stämpfli and co-authors. The lower number of hens on the nest access platforms in front of IN may be due to a better distribution around nests and tier changes within the aviary rack.

Based on these results, grids rather than perches provide for improved nesting behaviour, the Swiss group concluded.

Reference

^{Stämpfli K., T. Buchwalder, E.K.F. Fröhlich and B.A. Roth. 2013. Design of nest access grids and perches in front of the nests: Influence on the behavior of laying hens. Poult. Sci. 92(4): 890-899. doi: 10.3382/ps.2011-02046}