Association between personality traits of primiparous dairy cows and their response to prepartum training and subsequent adaptation to an automated milking system

The objective of this study was to investigate how the personality of primiparous cows relates to their adaptation to an automated milking system (AMS), and whether their individual personality was associated with response to training and subsequent adaptation to the AMS. Twenty-eight pregnant Holstein dairy heifers, enrolled in the study at approximately 3 wk before their expected calving date, were allocated into 1 of 2 treatments: control (CON; no training; n = 16), or training (TRN; including exposure to the AMS environment, concentrate, and mechanical arm and noises; n = 12). The TRN cows were trained to the AMS 14 ± 5.1 d (mean ± SD) before calving, for 3 training sessions per day for 4 d. All cows calved in singular maternity pens and were then moved to the AMS pen at approximately 4 DIM to be milked there. Ease of entry score to the AMS was recorded for all 12 training sessions and the first 6 milkings, and milking activity, behavior, and production were recorded for the first 21 d on the AMS. Cows were assessed for personality traits after the 21-d data collection period using a combined arena test composed of 3 parts: a novel arena test, a novel object test, and a novel human test. The personality traits of "active" and "bold-vocal" were identified through principal component analysis. During training, more bold-vocal cows had worse ease of entry scores to the AMS. However, personality did not influence AMS adaptation for TRN cows postcalving. For CON cows, more active and bold-vocal cows tended to perform worse on the AMS postcalving in terms of having more fetching events to the AMS and time spent in the fetch pen compared with CON cows that scored low for active and bold-vocal. Across all cows, active cows had more kickoffs compared with less active cows. Overall, these results demonstrate that personality influences response to training and adaptation to the AMS. However, prepartum AMS training may override the influence of individual-cow personality on their subsequent adaptation to the AMS, overcoming issues resulting from individual behavioral differences.