Significance of progesterone determination in milk.

The determination of progesterone in milk sampled on the day of insemination is used for fertilization check in dairy cattle. Thus, the corpus luteum function confirms insemination failures due to the false estrus. By this way it is possible to detect 10 to 20 per cent of cows which cannot be successfully inseminated. Further estimation is performed 3 weeks after the insemination when low concentration of progesterone reflects an insemination failure. By this way it is possible to follow up cows inseminated without success and without any clinical symptoms of the next estrus. The repeated estimation of progesterone can objectively monitor the corpus luteum function. This is of great importance for the confirmation of puerperal anestrus, diagnosis of fertility disorders and/or assessment of therapy of sexual cycle disorders.