Abstract

Human-animal interactions play a great role in animal welfare. Despite that chickens can establish positive bonds with humans, it remains unknown if broiler chickens can do this via social learning. This study examined whether observing conspecifics undergoing gentle handling (demonstrator chick) influences broiler chicks' fear and behavior toward humans through social learning mechanisms. One-day-old male broiler chickens (n = 72, distributed across 6 pens; 2 pens per treatment) were randomly assigned to one of three treatments: (1) gentle handling, where one demonstrator chick per pen received daily positive interactions with an experimenter for 15 days while observer chicks watched through a wire mesh divider; (2) human presence, where chicks were exposed daily to neutral human visual contact without direct interaction; and (3) control, without additional human contact. Behavioral responses toward humans were assessed when the chicks reached 31-32 days of age, with the demonstrator absent during testing. The assessment involved the experimenter entering each home pen for 5 minutes, allowing chicks to freely approach and interact. We recorded the time spent in proximity to the experimenter, latency to approach, and behaviors such as preening, alertness, and resting. The results demonstrated that observers of the gentle handling were more likely to approach the experimenter, did so more quickly, and spent more time nearby compared to those in the human presence and control groups. Additionally, control group chicks exhibited higher levels of alert behavior than those in the other treatments. Our results suggest that chicks witnessing another bird being gently handled feared humans less. While habituation through mere human presence had some effect, it was not as pronounced as observing direct positive interactions. This study highlights the potential of using social learning mechanisms to improve animal welfare in poultry by fostering positive human-animal relationships.