Lauber M C, Hemsworth P H, Barnett J L
CRC for Innovative Dairy Products, Australia.
Behav Processes. 2009 Nov;82(3):301-11. doi: 10.1016/j.beproc.2009.07.010. Epub 2009 Jul 29.
Three experiments examined the impact of breed, time spent with dam (TWD), gender, and late pregnancy induction of parturition and caesarean on the behavioural and heart rate responses of dairy calves at 2 and 6 weeks of age to Open field, Novel object and Startle tests and a Learning task. In Experiment 1 with male Jersey, Friesian and Friesian x Angus calves, there were some significant breed effects on responses to the Open field and the Novel object tests; Jersey calves appeared more curious and less fearful than Friesian x Angus calves. In Experiment 2, in which male and female Friesian calves were removed from their dams either between 0 and 12h or 12 and 24h after birth, there were no significant effects of gender or TWD. In Experiment 3, which studied the effect of induction of parturition using a long-acting glucocorticoid combined with short-acting progesterone 10 days prior to due calving date, there were no significant effects of late pregnancy induction of parturition. Across all three experiments, age at testing was the main factor influencing the responses of the calves. However, a number of interactions suggest that gender, time spent with dam and late pregnancy induction of parturition modified some of the responses to the tests as the calves developed.
三项实验研究了品种、与母牛相处时间（TWD）、性别、妊娠晚期引产和剖腹产对2周龄和6周龄奶牛犊在旷场试验、新物体试验、惊吓试验和学习任务中的行为和心率反应的影响。在实验1中，对雄性泽西牛、弗里斯兰牛和弗里斯兰×安格斯牛犊进行研究，发现品种对旷场试验和新物体试验的反应有一些显著影响；泽西牛犊比弗里斯兰×安格斯牛犊表现得更好奇、更不害怕。在实验2中，将雄性和雌性弗里斯兰牛犊在出生后0至12小时或12至24小时之间与它们的母牛分开，性别和TWD没有显著影响。在实验3中，研究了在预产期前10天使用长效糖皮质激素联合短效孕酮引产的效果，妊娠晚期引产没有显著影响。在所有三项实验中，测试时的年龄是影响牛犊反应的主要因素。然而，一些相互作用表明，随着牛犊的发育，性别、与母牛相处时间和妊娠晚期引产改变了对测试的一些反应。
