Epsilon Archive for Student Projects

Abstract

Prosocial behaviour is defined as an action that benefits others and has been studied across various animal species by different test paradigms. Studies conducted with laying hens are sparse. The aim of this study was to develop an apparatus to test for prosocial behaviour in laying hens maintained in large groups (n=225) in their home environment. Further, the study tested if the apparatus was biologically relevant for the hens to use, if they used it as intended. The study also investigated if the hens were consistent in their roles (as initiator or receiver). The “real” apparatus was designed as a seesaw, with a perch platform on one end and a reward hidden under a lightweight lid on the other. As one hen perched, the platform was lowered making the lid rise on the other side and the reward was available. A control apparatus, identical to the “real” but without any reward, was placed next to the “real” apparatus in the hens outside area of the pen. No prior training was required. Both apparatuses had RFID antennas underneath. All hens wore leg-mounted transponders, which were detected by the RFID system. A 14 non-consecutive day pilot was conducted, followed by a test period of 14 days, performed exclusively on weekdays over the course of three consecutive weeks. Both apparatuses were present for three hours simultaneously under strict observation. In this study, we recorded perching behaviour defined as a hen alighting on and remaining on the perch platform with one or both legs. Out of 200 registered hens, 67 were initiators on the “real” apparatus and 38 on the control. Wilcoxon signed rank was used to analyse the frequency of perching events and mean time perching for both “real” and control. The results showed 187 perching events occurred on the “real” apparatus, not evenly distributed across the days, and 62 on the control (P=0.0014), there was no significant difference in mean perching time between “real” (21.1s) and control (30.6s) (P=0.63). A 2-way ANOVA was used to analyse the consistency of the hens’ roles and there was a significant pattern in which role the hens took (P<0.001). These results indicate that the hens were motivated to use the apparatus and that the apparatus was biologically relevant as evidenced by their ability to operate both apparatuses. This is the first attempt of an apparatus developed to investigate prosocial behaviour in laying hens. Future refinement of the apparatus and continuous studies will contribute to knowledge to study prosocial behaviour in laying hens.