Association of rumination with milk yield of early, mid and late lactation dairy cows

Identification of the associations cow feeding behaviour with milk yield (MY) is important for supporting recommendations strategies that optimize MY. The objective this study was to identify between measures rumination time (RT) and MY using data collated from 2 777 dairy cows on nine commercial farms during years 2017 2019. A database contained daily data. Cows averaged (mean ± standard deviation) 2.7 1.6 lactations, 153 81 days in milk, 23.2 7.5 kg/day observation period. Behavioural included RT (504 93 min/day), (FT) (479 110 resting (360 94 activity (96 45 min/day). coefficient variation (min/day) 18.5%. behavioural differences observed provide a new insight into effects FT positively associated early mid-lactation correlation coefficients 0.24 (P < 0.001) 0.25 0.001), respectively. mean level (MRT) shown be correlated total produced over whole lactation (305 days). highest lowest MRT groups were 1 735 kg, 617 kg 941 first, second third lactation, High-yielding (≥ 23 kg/day) mid 30 achieved (522 3.54 min/day 507 3.17 min/day, P 0.05) (457 4.69 496 4.00 0.05), also had times most productive (early mid) phases which agreement our finding more spend greater proportion their ruminating.