Behavioral activity of dairy cows milked in a free traffic automated milking system

Abstract

The aim of this study was to investigate the behavioral activity of lactating cows kept in an automatic milking system (AMS) with free cow traffic. Thirty-two lactating Holstein dairy cows (13 primiparous and 19 multiparous) with a lactation number of 1.94 ± 0.2 (mean ± SD), days in milk of 152 ± 13.2 d, and a milk yield of 31.0 ± 1.8 kg/d were enrolled in the study. The cows had access to 2 single-box AMS. Durations of individual acts of behavior was determined by visual observations of individual cows over 3 days and was calculated for each day of observation. Cows spent 280.8 ± 11.2 min/d eating. This eating time was dividing into 9.2 ± 0.4 bouts/d, which lasted 30.7 ± 1.0 min. This accounted for 19.5% of total time spent eating. The cows' lying time was 660.9 ± 27.9 min/d, lying bout frequency was 7.4 ± 0.4 bouts/d, and the lying bout duration was 89.2 ± 23.3 min/bout and accounted for 45.9% of the total time spent lying. The rumination activity time of cows was 508.0±3.6 min/d, the rumination activity bout frequency was 11.9±0.4 bouts/d, and the duration of a rumination activity bout was 39.3 ± 1.0 min. This accounted for 36,2% of total time spent rumination activity. The standing time of cows was 779.1 ± 27.9 min/d or 54.1% of the total time, and the walking time of cows was 10.3 ± 0.5 min/d or 0.7% of the total time. The milking time of cows is 20.49 ± 0.92 min/d (or 1.4% of the total time), milking frequency is 3.2 ± 0.1 times per day, milking bout duration is 5.49 ± 0.92 min/times. These results add to body of literature on cow behavioral activity under AMS conditions.