McGreevy P, Nicol C
Department of Clinical Veterinary Science, University of Bristol, UK.
Physiol Behav. 1998 Aug;65(1):15-23. doi: 10.1016/s0031-9384(98)00070-5.
Crib-biting in the horse is frequently prevented in the short-term by horse-owners using physical means. Because it has been proposed that crib-biting may function to reduce stress, the effect of prevention of crib-biting and/or eating on the behaviour, heart rate, and plasma cortisol and beta-endorphin concentrations was measured in six crib-biting and six normal horses. When crib-biters were unable to crib-bite, they showed an increase in ingestive behaviour. When crib-biters were prevented from crib-biting and eating, a relative stasis in the motility of the foregut occurred, suggesting that normal gut function in these animals depends on ad libitum access to food and to suitable crib-biting substrates. There was no significant difference in the mean baseline levels of normal and crib-biting horses but, contrary to expectations, beta-endorphin levels were higher in crib-biting horses than in normal horses when crib-biting was prevented. Mean baseline levels of cortisol were higher, under a variety of test and control conditions, in crib-biting than in normal horses, but there was no significant rise in cortisol levels in crib-biters during periods when crib-biting was prevented, suggesting that the function of this oral stereotypy does not lie in stress-reduction.
马主通常会采用物理方法在短期内预防马匹咬槽行为。由于有人提出咬槽行为可能起到减轻压力的作用，因此对6匹咬槽马和6匹正常马进行了测量，以观察预防咬槽行为和/或进食对其行为、心率、血浆皮质醇和β-内啡肽浓度的影响。当咬槽马无法咬槽时，它们的摄食行为会增加。当咬槽马被阻止咬槽和进食时，前肠的蠕动会出现相对停滞，这表明这些动物的正常肠道功能依赖于随意获取食物和合适的咬槽底物。正常马和咬槽马的平均基线水平没有显著差异，但与预期相反，当咬槽行为被阻止时，咬槽马的β-内啡肽水平高于正常马。在各种测试和对照条件下，咬槽马的皮质醇平均基线水平高于正常马，但在阻止咬槽行为期间，咬槽马的皮质醇水平没有显著升高，这表明这种口腔刻板行为的功能并不在于减轻压力。
