Comparison of two systems of pasture allocation on milking intervals and total daily milk yield of dairy cows in a pasture-based automatic milking system

摘要

In pasture-based automatic milking systems (AMS), cows usually have a lower milking frequency (MF, the number of milking events in any 24 h period) than those reported in indoor housing systems (Garcia and Fulkcrson 2005). Moreover, milking intervals(MI, the interval between consecutive milking events, measured at every milking session in hours since the previous milking event) arc higher, with up to 30% of milking events occurring with intervals above 16 h in grazing systems (NA Lyons unpublished data). Milking events occurring with long intervals have a negative effect on milk yield (Schmidt 1960) and udder health (Hammer et al. 2012).Recognising that feed is the main incentive to achieve voluntary cow traffic (Prescott et al. 1998), some initial reports have depicted the potential importance and effect of incentives put in place per day (Jago et al. 2007). Yet to date no research hasbeen published that quantifies the actual impact of number of feed allocations, on animal performance in pasture-based systems.The aim of this study was to determine the impact of 2 different grazing treatments (2-way grazing [2WG] versus 3-way grazing [3 WG] allocations of feed per 24 h period), on MI, MF and daily milk yield (DY, in kg milk/d). It was hypothesised that an increase in frequency of feed allocation would result in increased cow traffic, MF and DY.