Conductimetric Milk Meter: Preliminary Results

Accurate milk yield measurement is important in maintaining production efficiency and improving farm management: yield data enable to implement and evaluate feed rations for individual cows or groups, calculate actual lactation curves and identify potential health problems proactively. Actually, many electronic milk metering devices based on different methods of measurement are available on the market. Accuracy over a wide range of flow rates, foaming effect on milk yield measurement, vacuum drop across the meter and reliability under widespread farm conditions are the key problems of currently available electronic milk meters. Aim of this project was the development of a low-cost and compact “straight-thru” milk meter that bases its functionality on the measurement of the electrical conductivity of the milk flowing through the meter. A prototype of the milk meter was built up during 2004 and tested in laboratory during 2005 using as experimental setup: a conductimetric card, a portable PC with a data acquisition and A/D conversion card and a software application developed by LabVIEW© 6.01 embedded, a suitable milking unit (artificial udder). The tests were made at constant flow rates, from 1.0 kg/min. to 12.0 kg/min, and carried out as requested from the approval procedures of the International Committee for Animal Recording (ICAR). Obtained results showed: a good accuracy at all the flows rates tested (average bias of 1.4 %) but at the same time a low reproducibility (SD of 5.0%) on the measurement.