Automated, longitudinal measures of drinking behavior provide insights into the social hierarchy in dairy cows

• Published in: JDS communications 2024-09, Vol.5 (5), p.411-415
• Main Authors: Foris, Borbala, Vandresen, Bianca, Sheng, Kehan, Krahn, Joseph, Weary, Daniel M., von Keyserlingk, Marina A.G.
• Format: Article
• Language: English
• Subjects: Health, Welfare, and Behavior
• ISSN: 2666-9102; 2666-9102
• DOI: 10.3168/jdsc.2023-0487

[Display omitted] •The social hierarchy at drinkers can be automatically assessed in groups of cows.•Dominance hierarchies at drinkers and feeders were moderately correlated.•The drinker-based hierarchy was stable between hot and normal temperature periods.•Cows' dominance influenced when, how often, and how much they drank. Dairy cows compete for feed and water access on commercial farms. In this study we used EloSteepness to assess the summed Elo winning probabilities (i.e., dominance) of 87 cows housed in a dynamic group and compared the resulting social hierarchies based on their steepness (i.e., the average degree of differences in winning probability between adjacently ranked individuals in the group, ranging from 0 to 1). We identified a hierarchy at the drinker with a steepness of 0.55 ± 0.02 (SD), whereas the hierarchy detected at the feeder during the same time period was 0.45 ± 0.02, indicating smaller dominance differences among cows when competing for feed compared with competing for water. Individual cows' winning probabilities at the feeder and drinker were moderately correlated (rs = 0.55), and cows at the lower and upper ends of the hierarchy showed good agreement. We compared the drinker hierarchy between hot (i.e., temperature-humidity index [THI] ≥72) and normal (i.e., THI