Supplementary material to: Don’t forget the dams! Dairy cows’ responses to two separation methods after 3 months of cow-calf contact

Supplementary material to the following publication: Vogt, A., Waiblinger, S., Palme, R., König von Borstel, U. & Barth, K. (TBC) Don’t forget the dams! Dairy cows’ responses to two separation methods after 3 months of cow-calfcontact. Journal of Dairy Science. TBC.

Abstract
Weaning and separation remain among some of the biggest challenges for cow-calf contact systems, making the development of practical and low stress separation methods mandatory for future success of these systems. This study aimed to compare behavioral and physiological responses of dairy cows to separation from their calves after 3 months of full-time contact with either the two-step method (NF, 2 wks full-time contact while calves wore a nose flap, 1 wk fence-line contact before total separation, n=18) or by gradual reduction of contact time between cow and calf (GR, 1 wk half day contact, 1 wk morning contact, 1 wk fence-line contact before total separation, n=18). Vocalizations and searching behavior were observed on 4 days/wk from 1 wk before separation until 1 wk after total separation. During the same period, lying behavior and rumination time was automatically assessed via accelerometers and pressure sensors. Fecal and blood samples were collected twice/wk from day -1 till +23 relative to separation start for analysis of fecal cortisol metabolites and the immune response. Milk yield in the parlor was continuously recorded. Statistical analysis was conducted using linear mixed effects models. We found no difference between the two separation methods in any of the examined behavioral and physiological response variables. However, a significant increase in vocalizations and searching behavior compared to baseline was present with both methods. Further, there was a transient increase in physiological distress markers and a short-lived retention of milk yield at initiation of treatments, indicating that both methods induced distress for the cows. Descriptively, there were large inter-individual differences between cows as well as a different temporal distribution in occurrence of behavioral responses, as GR cows vocalized most frequently during the week with fence-line contact and after total separation from the calf, while NF cows reacted strongest during the 2 wks while calves wore the nose flap. Milk yield was higher in NF than GR cows during the 2 wks while GR calves had time-restricted access to their dams and NF calves were prevented from suckling, but showed no difference afterwards anymore. However, similar evening milk yields of GR cows in the weeks with half day and morning contact, indicated that the weekly reductions in contact time worked in a rather stepwise than gradual manner, which warrants further improvement of the GR method. Taken together, results showed that cows experienced distress during separation with the GR method, when implemented over 3 wks in 3 steps, as well as with the NF method, but differences between individuals were considerable.

补充材料参见以下出版物：Vogt, A., Waiblinger, S., Palme, R., König von Borstel, U. & Barth, K. (待定) 请勿忽视隔离措施！奶牛在经历3个月与犊牛全程接触后对两种隔离方法的反应。奶牛科学杂志。待定。

摘要

断奶与隔离仍是对母犊接触系统构成的一些重大挑战，因此，开发出实用且低应激的隔离方法对于这些系统未来的成功至关重要。本研究旨在比较奶牛在经历与犊牛3个月全程接触后，对两种隔离方法的（两步法：NF，犊牛佩戴鼻瓣进行2周全程接触，在完全隔离前一周进行围栏接触，n=18；逐步减少接触时间法：GR，一周半天接触，一周早晨接触，一周围栏接触，在完全隔离前，n=18）的行为和生理反应。从隔离前一周至完全隔离后一周，每周观察4天，记录发声和搜寻行为。在同一时期，通过加速度计和压力传感器自动评估躺卧行为和反刍时间。从隔离开始前1天至隔离后23天，每周采集两次粪便和血液样本，用于分析粪便皮质醇代谢物和免疫反应。在挤奶厅持续记录产奶量。使用线性混合效应模型进行统计分析。我们发现，在所检查的任何行为和生理反应变量中，两种隔离方法之间均无差异。然而，与基线相比，两种方法均存在发声和搜寻行为的显著增加。此外，在治疗方法开始时，生理痛苦标志物的短暂增加和产奶量的短暂保留，表明两种方法均使奶牛感到痛苦。描述性分析表明，奶牛个体间差异较大，以及行为反应发生的时空分布不同，因为GR奶牛在围栏接触周和与犊牛完全分离后发声频率最高，而NF奶牛在犊牛佩戴鼻瓣的2周内反应最为强烈。在GR犊牛有限接触其母亲且NF犊牛被禁止吮吸的2周内，NF奶牛的产奶量高于GR奶牛，但之后不再存在差异。然而，GR奶牛在半日接触和早晨接触周晚上产奶量相似，表明每周接触时间的减少是以较为阶梯式而非渐进式的方式进行的，这需要对GR方法进行进一步改进。综合结果，奶牛在采用逐步实施3周的GR方法进行隔离时，以及采用NF方法时均感到痛苦，但个体差异相当显著。