Colostrum, a milk particularly rich in numerous components. Is it possibleto detect its unlawful addition in milk supplies?

The concentration of numerous proteins, enzymes, hormones, growth factors, vitamins, mineral and trace elements decreases abruptly during the first mi lkings post-partum and then increases in late lactation and during the udde r involution before calving. Therefore, colostrum cannot be precisely defin ed since it is a milk all the more abnormal than it is milked closer from c alving. So its unlawful addition to milk supply may only be detected by the modification of the normal composition of the milk. From all the component s reviewed, IgG are the most documented and sensitive indicators of an abno rmal milk. They can be easily quantified using a semi-automatised single ra dial immunodiffusion technique and threshold values characteristic of an ab normal milk have been defined taking into account the volume of the milk su pply. (C) Inra/Elsevier, Paris.