title: Determination of lying behavior patterns in healthy beef cattle by use of wireless accelerometers.
abstract: OBJECTIVE
  To describe daily, hourly, and animal-to-animal effects on lying behavior in steers.
  
  
  METHODS
  25 crossbred beef steers.
  
  
  METHODS
  Wireless accelerometers were used to record behavioral data for cattle housed in a drylot cattle research facility during two 20-day periods (winter 2007 [n = 10 steers] and spring 2008 [15]). Behavioral data were categorized into lying, standing, and walking behaviors for each time point recorded. Logistic regression models were used to determine potential associations between the percentage of time spent lying and several factors, including time (hour) of day, day of trial, and steer.
  
  
  RESULTS
  Lying behavior was significantly associated with hour of day, and a distinct circadian rhythm was identified. Steers spent > 55% of the time between 8:00 pm and 4:00 am lying and were most active (<30% lying behavior) during feeding periods (6:00 am to 7:00 am and 4:00 pm to 5:00 pm). Model-adjusted mean percentage of time spent lying was significantly associated with study day and was between 45% and 55% on most (27/40 [67.5%]) days. Lying behavior varied significantly among steers, and mean ± SD percentage of time spent lying ranged from 28.9 ± 6.1 % to 66.1 ± 6.6%.
  
  
  CONCLUSIONS
  Cattle had distinct circadian rhythm patterns for lying behavior, and percentage of time spent lying varied by day and among steers. Researchers need to account for factors that affect lying patterns of cattle (ie, time of day, day of trial, and individual animal) when performing research with behavioral outcomes.
authors: Departments of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA.
authors: Bradley D
authors: BD
authors: Robért
authors: Brad J
authors: BJ
authors: White
authors: David G
authors: DG
authors: Renter
authors: Robert L
authors: RL
authors: Larson
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D002417:Cattle / Q000502:physiology*; D002940:Circadian Rhythm; D008297:Male; D008991:Monitoring, Physiologic / Q000295:instrumentation* / Q000662:veterinary*; D009068:Movement