This study aimed to explore the relationship between caecal microbiota composition and movement patterns in laying hens, with the goal of understanding how gut microbial communities may be linked to individual behavioral traits. Using individually tracked hens housed in a multi-tier aviary system, researchers continuously monitored spatial use and identified notable differences in area preferences. Through 16S metabarcoding of 237 caecal samples, the study found a significant association between microbiota profiles and movement behavior, specifically the frequency of litter visits.

In this study, we explored the link between caecal microbiota composition and movement patterns in laying hens. We used hens from a Hendrix Genetics parent line, whose movements were individually and continuously tracked in a connected 3-tier aviary. The aviary included several vertical zones: an outdoor winter garden, a ground floor with litter, and three internal tiers with feed, water, nests, and perches. Hens showed clear differences in how they used these spaces, particularly in how often and how long they visited the litter and winter garden areas. Microbiota analysis based on 16S metabarcoding of 237 caecal samples showed an association (P < 0.05) between microbiota composition and the frequency of litter visits. We found notable differences (adjusted P < 0.05) in five bacterial families and seven genera between hens that frequently visited the litter (>30 times/day, LIT+) and those that rarely did (<10 times/day, LIT-). LIT- hens had higher levels of Coriobacteriales, Peptococcales, Oribacterium, and Lachnoclostridium, taxa previously linked to stress in various species. These findings highlight a potential role of the gut microbiota in shaping or reflecting individual behavioral patterns in chickens.