• Effects of simulated quarter and udder teat cup removal settings on strip milk and milking duration in dairy cows

      Boloña, P. Silvia; Upton, J.; Reinemann, D. J.; Teagasc Walsh Fellowship Programme; University of Wisconsin-Madison (Elsevier, 2020-02-26)
      The aim of this study was to estimate the amount of milk left in quarters and udders and the milking duration for a variety of teat cup removal strategies. A combination of empirical data and simulated quarter and udder teat cup removal settings were used to make these estimates. Milking duration is an important factor in both automatic and conventional milking systems because it directly influences milking efficiency and hence can affect farm profitability. Strategies investigated in the literature to reduce milking duration include the application of different milk flow rate switch-points (milk flow rate at which the milking unit or teat cup is removed). Applying these milk flow rate switch-points can affect the amount of milk that is not harvested (strip milk). We are not aware of previous research analyzing strip milk yield and milking duration at the quarter level, across a range of quarter and udder milk flow rate switch-points. Quarter-level average milking duration decreased by 2 min, and strip milk increased 1.3 kg as quarter milk flow rate switch-point was increased from 0.2 kg/min to 1.0 kg/min. Using an end of milking criterion of removal of the teat cup at 50% of the quarter's rolling average milk flow rate resulted in a 0.4-min reduction in milking duration and a 0.08-kg increase in strip milk per quarter, compared with removal of the teat cup at 30% of the quarter's rolling average milk flow rate. Udder-level average milking duration decreased by 1.4 min, and strip milk increased by 0.76 kg (0.19 kg per quarter) as udder milk flow rate switch-point was increased from 0.2 kg/min to 1.0 kg/min. A 0.8-min reduction in cow milking duration and a 0.27-kg increase in strip milk at the udder level (0.08 kg per quarter) resulted when changing udder milk flow rate switch-point from 30% of the udder rolling average to 50% of the udder rolling average milk flow rate. This study provides quantitative estimates of the effect of teat cup milk flow rate switch-points on milking duration and strip milk yield.
    • Short communication: Effects of changing teatcup removal and vacuum settings on milking efficiency of an automatic milking system

      Upton, John; Bolona, P. Silva; Reinemann, D. J.; Teagasc Wash Fellowship Programme; University of Wisconsin-Madison; Lely, The Netherlands (Elsevier, 2019-08-22)
      The aim of this experiment was to assess strategies to reduce milking time in a pasture-based automatic milking system (AMS). Milking time is an important factor in automatic milking because any reductions in box time can facilitate more milkings per day and hence higher production levels per AMS. This study evaluated 2 end-of-milking criteria treatments (teatcup removal at 30% and 50% of average milk flowrate at the quarter-level), 2 milking system vacuum treatments (static and dynamic, where the milking system vacuum could change during the peak milk flowrate period), and the interaction of these treatment effects on milking time in a Lely Astronaut A4 AMS (Maassluis, the Netherlands). The experiment was carried out at the research facility at Teagasc Moorepark, Cork, Ireland, and used 77 spring-calved cows, which were managed on a grass-based system. Cows were 179 DIM, with an average parity of 3. No significant differences in milk flowrate, milk yield, box time, milking time, or milking interval were found between treatments in this study on cows milked in an AMS on a pasture-based system. Average and peak milk flowrates of 2.15 kg/min and 3.48 kg/min, respectively, were observed during the experiment. Small increases in maximum milk flowrate were detected (+0.09 kg/min) due to the effect of increasing the system vacuum during the peak milk flow period. These small increases in maximum milk flowrate were not sufficient to deliver a significant reduction in milking time or box time. Furthermore, increasing the removal setting from 30% of the average milk flowrate to 50% of the average milk flowrate was not an effective means of reducing box time, because the resultant increase in removal flowrate of 0.12 kg/min was not enough to deliver practical or statistically significant decreases in milking time or box time. Hence, to make significant reductions in milking time, where cows have an average milk flow of 2 kg/min and yield per milking of 10 kg, end-of-milking criteria above 50% of average milk flowrate at the quarter level would be required.