title: Efficacy and effects of various anti-crib devices on behaviour and physiology of crib-biting horses.
abstract: BACKGROUND
  Crib-biting is a common oral stereotypy. Although most treatments involve prevention, the efficacy of various anti-crib devices, including surgically implanted gingival rings, has thus far not been empirically tested.
  
  
  OBJECTIVE
  Demonstrate the effect that 2 anti-crib collars, muzzle and gingival rings have on crib-biting, other maintenance behaviours, and cortisol levels in established crib-biting horses.
  
  
  METHODS
  Randomised, crossover clinical trial.
  
  
  METHODS
  In Experiment I, 2 anti-crib collars and a muzzle were used on 8 established crib-biting horses; horses wore each of 3 devices for 7 days, with a 7-day device-free period between treatments. Horses were video recorded for 24 h at least 3 times each week prior to any device placement, and always the day after a device was removed. In Experiment II, gingival rings were used in 6 established crib-biting horses; horses were video recorded for 3 days prior to ring implantation and the day after surgery until the rings became ineffective. Plasma cortisol levels were assessed every day during Experiment II and on Days 1, 3 and 5 of each week during Experiment I.
  
  
  RESULTS
  All devices significantly reduced crib-biting compared with control periods. There was no significant difference in crib-bite reduction amongst devices in Experiment I, or between pre-device periods and the first day the device was removed. The only increase in plasma cortisol occurred on the day of surgery in Experiment II.
  
  
  CONCLUSIONS
  Common anti-crib devices are effective in reducing crib-biting and significant distress was not evident from our findings. We did not find a post inhibitory rebound effect. Surgical rings were successful only temporarily and implantation was probably painful to the horses. Because stereotypies involve suboptimal environmental conditions, efforts should be made to improve husbandry factors previously shown to contribute to crib-biting, and research into decreasing horses' motivation to crib-bite should continue.
authors.affiliation: Department of Clinical Sciences, Cornell University College of Veterinary Medicine, Ithaca, New York, USA. jalbrig1@utk.edu.|Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, USA. jalbrig1@utk.edu.
authors.forename: J D
authors.initials: JD
authors.lastname: Albright
authors.affiliation: Department of Clinical Sciences, Cornell University College of Veterinary Medicine, Ithaca, New York, USA.|Clinical Science and Services, Royal Veterinary College, University of London, London, UK.
authors.forename: T H
authors.initials: TH
authors.lastname: Witte
authors.affiliation: Department of Biomedical and Diagnostic Sciences, The University of Tennessee College of Veterinary Medicine, Knoxville, USA.
authors.forename: B W
authors.initials: BW
authors.lastname: Rohrbach
authors.affiliation: Department of Biomedical and Diagnostic Sciences, The University of Tennessee College of Veterinary Medicine, Knoxville, USA.
authors.forename: A
authors.initials: A
authors.lastname: Reed
authors.affiliation: Department of Clinical Sciences, Cornell University College of Veterinary Medicine, Ithaca, New York, USA.
authors.forename: K A
authors.initials: KA
authors.lastname: Houpt
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D006734:Horse Diseases / Q000517:prevention & control*; D006736:Horses / Q000502:physiology*; D013239:Stereotyped Behavior
keywords: behaviour; crib collar; crib rings; crib-biting; horse; stereotypy