Miller-Cushon E K, DeVries T J
Department of Animal Sciences, University of Florida, Gainesville 32611.
Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
J Dairy Sci. 2016 Feb;99(2):1406-1417. doi: 10.3168/jds.2015-9869. Epub 2015 Dec 10.
This study investigated how social housing affects pre- and postweaning feeding behavior and social feeding preferences of dairy calves. Twenty Holstein bull calves were housed either individually (IH; 10 calves) or in pairs (PH; 10 calves) from birth. Calves were offered grain concentrate and milk replacer ad libitum via an artificial teat (1 teat provided per calf) and weaned by incrementally diluting the milk replacer from 39 to 49 d of age. Postweaning, IH calves were paired within treatment and all pens (n=5 per treatment) were offered a complete pelleted diet ad libitum and followed until 13 wk of age. We recorded feeding times from video for 3 consecutive days in wk 6, 9, and 12 of age and used this to calculate daily meal frequency and meal duration. In wk 9 and 12, frequency and duration of synchronized feeding were also calculated. In addition, preference tests were conducted at time of feed delivery in wk 10 to assess the preference of each calf to feed alongside or out of visual contact of their pen mate. Pair-housed calves consumed more concentrate, in more frequent meals, than IH calves in the week before weaning (wk 6) and continued to have greater concentrate intake during weaning. Milk intake was not affected by treatment, but calves in PH pens consumed their milk in more frequent and smaller meals. Postweaning, intake was similar between treatments, but calves raised in PH pens continued to have meals that were more frequent and shorter in duration. Both treatments had a similar frequency of synchronized meals. However, when offered a choice to feed alone or alongside their pen mate during preference testing, calves raised in PH pens spent more time feeding in the presence of their pen mate than calves raised in IH pens. These results suggest that meal patterns established in response to different early social environments may persist after weaning and that early social contact may have longer-term effects on social feeding behavior.
本研究调查了社会住房如何影响犊牛断奶前后的采食行为以及社会采食偏好。20头荷斯坦公牛犊从出生起分别单独饲养(个体饲养组,10头犊牛)或成对饲养(成对饲养组,10头犊牛)。通过人工奶嘴(每头犊牛提供1个奶嘴)随意提供谷物浓缩料和代乳粉,在39至49日龄时通过逐步稀释代乳粉进行断奶。断奶后,个体饲养组的犊牛在处理组内配对,所有栏舍(每个处理5个栏舍)随意提供完整的颗粒饲料,并持续观察至13周龄。我们在犊牛6周龄、9周龄和12周龄时连续3天从视频中记录采食时间,并用此计算每日采食频率和采食持续时间。在9周龄和12周龄时,还计算了同步采食的频率和持续时间。此外,在10周龄饲料投喂时进行偏好测试,以评估每头犊牛与同栏伙伴一起采食或在视觉接触范围外采食的偏好。在断奶前一周(6周龄),成对饲养的犊牛比个体饲养组的犊牛采食更频繁,消耗的浓缩料更多,并且在断奶期间继续有更高的浓缩料摄入量。采食量不受处理方式的影响,但成对饲养栏舍中的犊牛采食牛奶的频率更高且每餐量更小。断奶后,不同处理组的采食量相似,但成对饲养栏舍中饲养的犊牛采食频率更高且每餐持续时间更短。两种处理方式的同步采食频率相似。然而,在偏好测试中,当提供单独采食或与同栏伙伴一起采食的选择时,成对饲养栏舍中饲养的犊牛在同栏伙伴在场时采食的时间比个体饲养组的犊牛更长。这些结果表明,因不同早期社会环境而形成的采食模式在断奶后可能会持续存在,并且早期社会接触可能对社会采食行为有长期影响。