PPILOW first results: Foraging, an early behavioural predictor of range use in free-range broiler chickens?  – by Vitor Bessa-Ferreira and Vanessa Guesdon (JUNIA)

Free-range broiler chickens – © JUNIA

Many species prefer to make efforts to acquire their food (or contra-freeload, in scientific language), even when they have readily available food sources, at no cost. The contra-freeloading phenomenon also happens in free-range chicken systems. Although chickens have ad libitum food in the barn, they spend some of their energy exploring and searching for food (i.e., foraging) in the range. In a recent paper (Ferreira et al., 2021), researchers from JUNIA and INRAE tested whether individual differences in range use were linked to contra-freeload. They followed chickens’ behaviour all over their productive cycle, from chicks, before they had access to the range, until some days before slaughter. They also tested chicken behaviour in a standardized testing situation: in a two-chambered apparatus, chickens were exposed to a chamber where the mealworms were readily available on the floor, while in the other chamber, mealworms were mixed with foraging substrates, therefore finding and eating them was more difficult. Finally, to test their contra-freeloading motivation, chickens were exposed to both empty chambers. The time spent on each one was quantified. The results showed that chickens who spent more time foraging in their home environment (barn and range) and those who preferred the chamber where mealworms were hardly accessible were more prone to use the range than those who foraged less and preferred eating the easily accessible mealworms. Interestingly, the results also showed that these differences can be seen in chicks before they accessed the range, which points to an early predictive behaviour of range use that merits further investigation. Follow-up experiments are in progress, more results to come in a future PPILOW newsletter.


Ferreira, V. H. B., A. Simoni, K. Germain, C. Leterrier, L. Lansade, A. Collin, S. Mignon-Grasteau, E. Le Bihan-Duval, E. Guettier, H. Leruste, L. Calandreau, V. Guesdon. 2021. Working for food is related to range use in free-range broiler chickens. Sci. Rep. 11:6253. Available at https://doi.org/10.1038/s41598-021-85867-2