Institute of Animal Breeding and Genetics, Professorship of Animal Husbandry, Behaviour and Welfare Justus-Liebig-University Giessen, Leihgesterner Weg 52, 35392Giessen, Germany.
J Dairy Res. 2020 Aug;87(S1):138-143. doi: 10.1017/S0022029920000527.
The study reported in this research communication aimed to assess the influence of maternal contact on calves' activity, fearfulness, and social competence. Calves were either dam-reared for their first 14 d of age (Maternal Contact, n = 12) or were separated from their dams within 12 h after birth (Motherless, n = 12). Calves of both treatments and the dams of Maternal Contact calves were group-housed and suckling was prevented with udder nets. The general activity (lying, locomotion, swapping between lying and standing) was measured using pedometers in eight Maternal Contact and eight Motherless calves within a 24-d period. Since general activity might be affected by calves' age or the separation of Maternal Contact calves from the dams the 24-d period was additionally divided into two groups (period A: 3rd-13th day of age, period B: 14th-27th day of age). Emotionality and social competence were assessed in the open field, novel object, and confrontation test with an unknown cow at 14, 21, and 28 d of age, respectively. Mann-Whitney-U-tests were performed for statistical analysis. Locomotion was greater in Motherless calves than Maternal Contact calves during the 24-d period (A + B combined, P < 0.001) and period B (14th to 27th day of age, P < 0.001). There was no treatment difference in duration of lying or in the amount of swapping in any of the periods. After a Bonferroni correction, which we used due to the exploratory character of the study, there were no treatment differences in behaviours indicating emotionality. Compared to Motherless calves, Maternal Contact calves showed increased vigilance (P < 0.01) during the confrontation test. The results of this study indicate that mother-reared calves likely searched less for social contact and developed greater social skills than calves that were separated from their mothers soon after birth.
本研究通讯报道的研究旨在评估母体接触对犊牛活动、恐惧和社交能力的影响。犊牛在出生后 14 天内（母体接触，n = 12）或在出生后 12 小时内与母羊分离（无母，n = 12）。两种处理方式的犊牛及其母羊均被群养，并使用奶头网阻止犊牛吸吮。使用计步器测量了 8 只母体接触和 8 只无母犊牛在 24 天内的一般活动（躺卧、运动、躺卧和站立之间的转换）。由于一般活动可能会受到犊牛年龄或母体接触犊牛与母羊分离的影响，因此将 24 天的时间进一步分为两组（第 3-13 天为 A 期，第 14-27 天为 B 期）。在 14、21 和 28 日龄时，分别在开阔场地、新物体和与未知奶牛的对抗试验中评估了情感和社交能力。采用曼-惠特尼 U 检验进行统计分析。在 24 天期间（A + B 合并，P < 0.001）和 B 期（第 14-27 天），无母犊牛的运动比母体接触犊牛多。在任何时期，躺卧时间或转换次数均无处理差异。由于该研究具有探索性，因此在进行 Bonferroni 校正后，在表示情感的行为上没有处理差异。与无母犊牛相比，母体接触犊牛在对抗试验中表现出更高的警惕性（P < 0.01）。本研究结果表明，与出生后不久就与母羊分离的犊牛相比，被母羊饲养的犊牛可能较少寻求社交接触，并发展出更强的社交技能。
