Integrating technology and animal welfare: space and resource use of individual non-cage laying hens

Abstract Text: Little is known about individual behavior and resource use of laying hens housed in non-cage systems.  As more hens are housed in large groups, and their welfare assessed accordingly, understanding individual hen behavior and resource use is paramount.  Therefore, a wireless body-mounted sensor system was developed to track the location of individual laying hens in a non-cage environment. The ethics of technology development stimulated discussion with regards to animal welfare assessment through a Philosophy of Technology lens.   Investigations illustrated that wearing the sensor had a minimal negative long-term effect on resource use or agonistic behavior, suggesting that hens habituated to wearing the sensor. Furthermore, two parsimonious sampling strategies were identified for monitoring the behavior of individually identifiable hens to facilitate further data collection.  Using this newly identified sampling strategy, individual hen behavior and sensor data were collected at 19, 28, 48, and 66 wk along with physical assessments as described in the Welfare Quality^®Assessment Protocol for Poultry.  Mean differences in the amount of time hens performed different behaviors, and differences in the variability of behavior performance were assessed.  These results highlighted that though group averages may not change, individual hens may vary in their physical condition and behavioral repertoire.  We synced spatially-explicit locational information from the hen-worn sensor system with video-based behavioral observations.  We digitally recreated the hen enclosure in ArcMap 10.0, to develop a Geographic Information System (GIS) to model hen behavior in non-cage environments.  By combining behavior and sensor data in GIS, we developed a spatiotemporal representation of individual hen behavior.  Data from 48 and 66 wk was used to characterize individual hen behavior through utilization distributions, hot spot mapping, and conspecific ranging overlap calculations.  Feeding and foraging were specifically targeted to identify spatiotemporal patterns in appetitive behaviors that were or were not constrained by the location of the resource for its performance.  Preening was targeted as a grooming and social behavior that could indicate a hen’s affective state.  These results provide new insight into individual hen behavior and present a platform for a new type of agricultural research.  Yet, technology in agriculture is a double-edged sword, especially as regards animal welfare and should be utilized when appropriate, and relinquished when necessary.  Integrating wildlife tracking techniques within agricultural management research may provide insight into hen welfare and can be utilized when developing best practices or designing new housing environments.

Keywords: animal behavior, animal welfare, laying hen