Bailly-Caumette E, Bertelsen M, Jensen M B
Department of Biology, Ecole Normale Supérieure de Lyon, 69007 Lyon, France.
Department of Animal and Veterinary Sciences, Aarhus University, 8830 Tjele, Denmark.
JDS Commun. 2023 Apr 18;4(4):278-283. doi: 10.3168/jdsc.2022-0337. eCollection 2023 Jul.
This study investigated play behavior of dairy calves kept with the cow either full time or half time in groups of 4 dam-calf pairs in 68-m straw-bedded pens. Twenty-four of 48 calves entering the experiment (2 calves in each of 12 pens) were observed during 24 h at 3 and 7 wk of age. The total duration of locomotor play did not differ between the 2 treatments, but full-time calves performed less frontal pushing (social play). Irrespective of treatment, calves performed less parallel locomotor play and more frontal pushing at 7 wk than 3 wk of age. Analyzing the intensity of play behavior during milking times (morning and afternoon, respectively), during the night and between morning and afternoon milking, showed that calves performed locomotor play more intensively after the cows had left the pen for milking than during other periods. The results illustrate the importance of space and external stimulation for the performance of play behavior.
本研究调查了在68平方米铺有稻草的围栏中，以4对母牛-犊牛为一组，犊牛与母牛全天或半天在一起时的玩耍行为。在进入实验的48头犊牛中，选取24头（12个围栏中每个围栏2头）在3周龄和7周龄时进行24小时观察。两种处理方式下，运动性玩耍的总时长没有差异，但全天在一起的犊牛进行正面推挤（社交性玩耍）的次数较少。无论处理方式如何，犊牛在7周龄时比3周龄时进行的平行运动性玩耍更少，正面推挤更多。分析挤奶时间（分别为上午和下午）、夜间以及上午和下午挤奶之间的玩耍行为强度，结果表明，母牛离开围栏去挤奶后，犊牛进行运动性玩耍的强度比其他时间段更大。研究结果说明了空间和外部刺激对玩耍行为表现的重要性。
