Minero M, Canali E, Ferrante V, Verga M, Odberg F O
Instituto di Zootecnica Veterinaria, Università degli Studi di Milano, Italy.
Vet Rec. 1999 Oct 9;145(15):430-3. doi: 10.1136/vr.145.15.430.
The heart rate and behaviour of 14 adult saddle horses, eight crib-biters and six normal controls, were investigated. Initially, the relationship between crib-biting and heart rate was investigated while the horses were undisturbed. The horses were tested when restrained with a lip twitch, and assessed when they were exposed suddenly to the rapid inflation of a balloon. The heart rate of the crib-biters during crib-biting was lower than during other behaviours. The crib-biters had a higher overall mean heart rate (P<0.05) suggesting that they may have had a higher basal sympathetic activity. After the application of the twitch, all the horses had a transient increase in heart rate which returned to basal values more rapidly in the crib-biters. The crib-biters were less reactive to the lip twitch, five of the six investigated remaining calm, and after the release of the twitch, they spent more time nibbling (P<0.05) than the control horses. The crib-biters reacted more strongly to the inflation of the balloon (three of the six reacted), and after it had been inflated they spent more time walking in the box.
对14匹成年鞍马（其中8匹有咬栏行为，6匹为正常对照）的心率和行为进行了研究。最初，在马匹不受干扰的情况下，研究咬栏行为与心率之间的关系。当用唇夹约束马匹时对其进行测试，并在它们突然暴露于气球快速充气时进行评估。有咬栏行为的马匹在咬栏时的心率低于其他行为时的心率。有咬栏行为的马匹总体平均心率较高（P<0.05），这表明它们可能具有较高的基础交感神经活动。使用唇夹后，所有马匹的心率都有短暂升高，有咬栏行为的马匹心率恢复到基础值的速度更快。有咬栏行为的马匹对唇夹的反应较小，6匹被调查的马匹中有5匹保持平静，松开唇夹后，它们啃咬的时间比对照马匹更长（P<0.05）。有咬栏行为的马匹对气球充气的反应更强烈（6匹中有3匹有反应），气球充气后，它们在围栏内行走的时间更长。
