The effect of short-term prevention on the subsequent rate of crib-biting in thoroughbred horses.

This research investigates the effect of temporarily stopping horses from crib-biting, a common equine behavior, and reports a notable increase in the tendency to crib-bite after the preventive measure was lifted.

Research Methodology

• The research involved eight thoroughbred horses that have a history of crib-biting, which was a repetitive behavior of biting on a non-food object and gulping air.
• These horses were fitted with a cribbing collar for a 24-hour duration. This collar is designed to hinder the horse’s ability to stretch their neck muscles and gulp air during crib-biting, thereby serving as a preventive measure.
• The effectiveness of the collar as a preventive device was successful in six out of the eight horses in the test group.

Results and Analysis

• An analysis of covariance was used to statistically control for initial differences in the crib-biting rate among the horses.
• The first day after the prevention phase, the horses showed a significant increase in crib-biting, indicating a “post inhibitory rebound.”
• The rebound effect was more pronounced in the test horses compared with control horses, and it was also considerably higher than their base rate of crib-biting.

Interpretation of Findings

• The researchers ruled out the possibility of the rebound being caused by an increased novelty of the cribbing bar or a rise in feeding motivation during the prevention time.
• Rather, it was suggested that the rebound was a result of an increased internal motivation to crib-bite during the period of prevention.
• According to the researchers, behaviors exhibiting this pattern of motivation are typically seen as functional, leading to the understanding that their prevention could potentially harm the horse’s welfare.

Implications of the Study

• The researchers argue that crib-biting might not be a mere stereotypic behavior, but could serve some functional value for the horse.
• The sudden increase in crib-biting after the removal of the collar indicates that such preventive measures might not be beneficial for the horse in the long-run, even if they temporarily cease the behavior.