Technical note: validation of data loggers for recording lying behavior in dairy goats.

Changes in standing and lying behavior are frequently used in farm animals as indictors of comfort and health. In dairy goats, these behaviors have primarily been measured using labor-intensive video and live observation methodologies. The aim of this study was to validate accelerometer-based data loggers for use in goats. Two commercial dairy goat farms in Ontario were enrolled; goats were fitted with data loggers on their rear left legs and the pens were equipped with video. Data loggers compared well with video in identifying lying and standing events on both farms (farm 1 and 2, respectively: sensitivity=99.7 and 99.8%, specificity=99.5 and 99.4%, false readings=0.43 and 0.36%). The loggers were also able to record if the goat was lying on her left or right side (farm 1 only: sensitivity=99.9%, specificity=99.3%, false readings=0.38%), but these measures were only accurate if the loggers were attached with sufficient tension to prevent logger rotation. The mature does enrolled on farm 1 spent 14.5±1.0h/d lying down and frequently changed lying side even within a single lying bout (24±5 shifts/d between left and right sides and 16±5 lying bouts/d). The young goats on the second farm averaged just 8.5±3.2h/d in lying time, and spread this time over 8±4 bouts/d. Data loggers accurately measured lying time and lying bouts in mature does and younger goats on both farms, and lying laterality (e.g., left and right lying sides) in mature does on farm 1.