THE EFFECT OF PULSATION RATIO ON TEAT CONDITION, SCC AND PRODUCTIVITY IN AUTOMATIC MILKING SYSTEMS

Discipline: management; Key words: pulsation ratio; automatic milking; teat health; udder health; SCC

The pulsation ratio of a milking machine affects milk flow and milking time. It may also influence teat condition and milk somatic cell count (SCC). However, most studies comparing pulsation ratios have been performed on conventional cluster milking (whole-udder level), where effects such as deteriorated teat end condition and increased milk SCC are likely to be caused by over-milking on teats that are emptied faster than the other teats. When the teat cups are detached from each udder quarter separately, which can be done in automatic milking systems, the risk of over-milking, especially in front teats, may be reduced. Whether this is indeed the case, and if so, does that allow one to increase milk flow rate was the topic investigated by Drs S. Ferneborg and K.  Svennersten-Sjaunja. Their results were published in the Journal of Dairy Research, Volume 82 of 2015, pages 453 to 459, with the title: The effect of pulsation ratio on teat condition, milk somatic cell count and productivity in dairy cows in automatic milking.

The authors measured the effects of pulsation ratio on teat end condition, milk SCC, milk yield, milking time and milk flow in an automatic milking system where each udder quarter was milked separately. In total, 356 cows on five dairy farms were included in a split-udder design experiment comparing three pulsation ratios (60:40, 70:30 and 75:25) with the standard pulsation ratio (65:35) during six weeks. The pulsation rate was set at 60 cycles per minute and the vacuum level 46 kPa.

The 70:30 and 75:25 ratios increased peak and average milk flow and the machine-on time was shorter with 75:25, whereas both peak and average milk flows were lower and machine-on time was longer with the 60:40 ratio. No negative effects on teat condition or milk SCC were observed with any of the pulsation ratios applied during the study. Thus, it appears possible to increase pulsation ratio to increase milking efficiency in automatic milking systems where quarter milking is applied.