Department of Animal Science, Michigan State University, East Lansing 48824, USA.
J Dairy Sci. 2012 Mar;95(3):1575-84. doi: 10.3168/jds.2011-4710.
Transitioning a dairy herd to an automatic milking system (AMS) from a conventional parlor system may be stressful for the cow, as many changes occur during this process. Chronic stress may affect the welfare of the cow, and acute stress during milking can decrease milk yield. Therefore, it is important to quantify if and how long stress during adaptation to an AMS might persist. Seventy-seven cows with acceptable udder and teat conformation that would not interfere with adaptation to the AMS and that were lactating n = 18, early [0 to 100 d in milk (DIM)]; n = 27, mid (100 to 200 DIM); and n = 32, late (200+ DIM) for the full duration of the project were chosen for observation. All cows had been milked previously in a double-6 herringbone milking parlor. Four stress-related behaviors [step-kick behavior both before and after attachment of teat cups, elimination (urination and defecation instances), and vocalization] were recorded during milking by trained observers, whereas milk yield was automatically recorded by the AMS. Data were collected for 24-h periods beginning on the day the cows transitioned to milking in the AMS (d 0), and on d 1, 2, 4, 8, 16, and 32 thereafter. Instances of elimination and vocalization were greater on d 0 compared with all other days (elimination: d 0 = 3.1 ± 0.09, d 1 = 0.6 ± 0.07, and 0 ± 0 instances thereafter; vocalization: d 0 = 1.7 ± 0.07, d 1 = 0.05 ± 0.04, and 0 ± 0 instances thereafter). Milk yield increased between d 0 (18.3 ± 1.7 kg) and d 1 (30.9 ± 1.7 kg). Primiparous cows (n=28) were more likely than multiparous cows (n = 49) to display step-kick behaviors both before (8.3 ± 2.5; 5.5 ± 0.6, respectively) and after (15.6 ± 2.4; 13.3 ± 1.3, respectively) teat cup attachment during milking. Eight days after introducing the cows to the AMS, over 60% of the herd was milking voluntarily and 95% of the herd was milking voluntarily within a month, which suggests that cows did not find the AMS aversive. Greater elimination and vocalization behavior and lower milk yield on d 0 relative to subsequent days indicated initial stress and discomfort with the milking process in the new system; however, the cows appeared to adapt within 24h.
将奶牛从传统的牛舍挤奶系统过渡到自动化挤奶系统（AMS）可能对奶牛造成压力，因为在此过程中会发生许多变化。慢性应激可能会影响奶牛的福利，而挤奶过程中的急性应激会降低产奶量。因此，重要的是要确定在适应 AMS 期间的应激是否存在以及持续时间。
选择了 77 头具有可接受的乳房和乳头形态的奶牛，这些奶牛不会干扰对 AMS 的适应，并且正在泌乳 n = 18，早期[0 至 100 天产奶（DIM）]；n = 27，中期（100 至 200 DIM）；n = 32，晚期（200+DIM），用于整个项目的观察。所有奶牛之前都在双 6 型鱼骨式挤奶厅挤奶。经过培训的观察员在挤奶过程中记录了 4 种与压力相关的行为[在连接奶杯前后的踢踏行为、排泄（排尿和排便）和发声]，而产奶量则由 AMS 自动记录。数据是在奶牛开始过渡到 AMS 挤奶的那天（第 0 天）以及之后的第 1、2、4、8、16 和 32 天开始的 24 小时期间收集的。与其他所有日子相比，第 0 天的排泄和发声次数更多（排泄：第 0 天=3.1±0.09，第 1 天=0.6±0.07，无此后的实例；发声：第 0 天=1.7±0.07，第 1 天=0.05±0.04，此后无实例）。第 0 天（18.3±1.7 公斤）和第 1 天（30.9±1.7 公斤）的产奶量增加。初产奶牛（n=28）比经产奶牛（n=49）在挤奶过程中更有可能在连接奶杯前后表现出踢踏行为（分别为 8.3±2.5；5.5±0.6）。
在向 AMS 引入奶牛 8 天后，超过 60%的奶牛自愿挤奶，95%的奶牛在一个月内自愿挤奶，这表明奶牛并不认为 AMS 有不良影响。与随后的日子相比，第 0 天的排泄和发声行为更多，产奶量更低，表明奶牛在新系统的挤奶过程中最初感到压力和不适；然而，奶牛似乎在 24 小时内适应了。
