Background: Cortisol is secreted into blood in reaction to acute stress, but also in phases of diminished feed intake and
changed animal behavior. As cows do not always show clear signs of discomfort, reliable diagnostic markers could be
used to provide information regarding individual cows’ distress. The objective of this study was to establish an ether free
immunoassay for the detection of cortisol and to determine values during the first 22 weeks of lactation. Furthermore, the
response in milk cortisol levels was assessed during times of metabolic stress and pain associated symptoms of lameness