University of Helsinki, Faculty of Veterinary Medicine, Department of Equine and Small Animal Medicine, Koetilantie 7, P.O. Box 57, 00014 Helsinki, Finland.
Vet J. 2012 Jul;193(1):97-102. doi: 10.1016/j.tvjl.2011.09.027. Epub 2011 Oct 29.
Crib-biting is classified as an oral stereotypy, which may be initiated by stress susceptibility, management factors, genetic factors and gastrointestinal irritation. Ghrelin has been identified in the gastric mucosa and is involved in the control of food intake and reward, but its relationship to crib-biting is not yet known. The aim of this study was to examine the concentration and circadian variation of plasma ghrelin, cortisol, adrenocorticotropic hormone (ACTH) and β-endorphin in crib-biting horses and non-crib-biting controls. Plasma samples were collected every second hour for 24h in the daily environment of eight horses with stereotypic crib-biting and eight non-crib-biting controls. The crib-biting horses had significantly higher mean plasma ghrelin concentrations than the control horses. The circadian rhythm of cortisol was evident, indicating that the sampling protocol did not inhibit the circadian regulation in these horses. Crib-biting had no statistically significant effect on cortisol, ACTH or β-endorphin concentrations. The inter-individual variations in β-endorphin and ACTH were higher than the intra-individual differences, which made inter-individual comparisons difficult and complicated the interpretation of results. Further research is therefore needed to determine the relationship between crib-biting and ghrelin concentration.
啃咬木栏被归类为一种口腔刻板行为，可能由应激易感性、管理因素、遗传因素和胃肠道刺激引起。胃饥饿素已在胃黏膜中被发现，它参与了食物摄入和奖励的控制，但它与啃咬木栏的关系尚不清楚。本研究旨在检测具有刻板啃咬行为的马和非啃咬对照马的血浆胃饥饿素、皮质醇、促肾上腺皮质激素 (ACTH) 和 β-内啡肽的浓度和昼夜变化。在 8 匹具有刻板啃咬行为的马和 8 匹非啃咬对照马的日常环境中，每两小时采集一次血浆样本，持续 24 小时。具有刻板啃咬行为的马的平均血浆胃饥饿素浓度明显高于对照马。皮质醇的昼夜节律明显，表明采样方案没有抑制这些马的昼夜调节。啃咬行为对皮质醇、ACTH 或 β-内啡肽浓度没有统计学上的显著影响。β-内啡肽和 ACTH 的个体间变异高于个体内差异，这使得个体间比较变得困难，结果的解释也变得复杂。因此，需要进一步研究以确定啃咬行为与胃饥饿素浓度之间的关系。
