Animal Behavior and Well-Being

摘要

A goal of dairy cattle management is to meet the nutritional requirementsof individuals, but there is large variability in behavior and performanceof cows. The objective of this study was to identify and associate personalitytraits with behavior and performance of cows milked in a free-trafficautomated milking system (AMS) and determine if the response to concentrateallocation in an AMS is associated with those personality traits.Holstein cows (n = 15; 124 ± 53 DIM; parity = 2.7 ± 0.9) were exposed to2 treatments in a crossover design with 2 consecutive 28-d periods: cowswere provided a basal PMR with a pelleted AMS concentrate allowanceof: 1) 3.0 kg/d (L-AMS) or 2) 6.0 kg/d (H-AMS). During the last 5 d ofthe first period, behaviors in response to a novel arena, object and humanwere scored to identify personality traits. Principal component analysisrevealed 5 factors interpreted as personality traits (2 from novel humantest = 72% cumulative variance; 3 from novel object and novel arena tests= 81% cumulative variance). Linear regressions were used to explore relationshipsbetween each factor and behavior and performance outcomes.Cows high on Factor 1 (active and vocal) had greater total DMI, sortingof the PMR, and lying bouts, but shorter lying bout duration (P < 0.01).Cows high on Factor 2 (fearful of human) had greater meal size (P =0.05), gained BW (P = 0.04), and required more AMS fetches (P < 0.01),likely explaining their lesser concentrate intake and milk yield (P < 0.01).These cows were less likely to meet their target concentrate allowance onthe H-AMS treatment (P < 0.01). Cows high on Factor 3 (active) gainedBW (P = 0.05) and had more problematic milkings (P < 0.01), likely explainingtheir lesser milk yield (P = 0.02). Cows high on Factor 4 (social)had greater meal frequency and SCC (P < 0.01) and lesser % milk fat (P= 0.03) and protein (P = 0.04). Cows high on Factor 5 (fearful of object)had greater eating rate (P = 0.02), rumination (P = 0.03), and % milkprotein (P = 0.01). These results indicate that personality traits of dairycattle are associated with feeding behavior and performance in an AMS.