Issues Related to Sampling and Analysis of Milk

摘要

Determination of the weight of milk produced, and sampling and testing of milk provides the information to make feeding and cow replacement management decisions in dairy herds. Milking parlor technology has changed from weigh jars to flow sensors andproportional milk sampling devices. With those changes, more management attention needs to be focused on control of the accuracy of the milk flow sensors that estimate weight of milk produced by a cow and representativeness of milk sampling. In addition,central laboratory mid-infrared (IR) transmittance milk analysis methods continue to evolve, enabling the measurement of minor milk components, such urea and fatty acids in milk. While, in general, it does not take additional time beyond that need for fat and protein to test milk for these new components using an Fourier Transform (FT)-IR, it does take extra time to do additional quality assurance validations of these new parameters, in addition to purchasing and using additional calibration and validation reference materials to control the accuracy of testing these additional milk components. These additional costs for measuring new milk components need to be balanced against the value of the new milk composition and production information for farm management decision making. Equipment is already available to measure the fat and protein of milk as the cow is being milked. For large farms, a cost effective approach for doing this testing at every milking will provide a rich new source of informationto make more timely feeding and management decisions.