Abstract
A new test strip for semiquantitative determination of beta-hydroxybutyric acid (BHB) in bovine milk has been tested in experimental investigations in three lactating cows. After intraruminal administration of butyric acid, the following parameters were determined during 7 hours: milk concentrations of BHB (quantitatively and semiquantitatively) and acetone (quantitatively), BHB concentration in blood and urine (quantitatively), acetone + acetic acid concentration in urine (semiquantitatively). The new quick-test proved to be highly sensitive and even subclinical or physiological levels of BHB in milk could be determined. It seems to be suitable not only for the diagnosis of clinically manifest ketosis in dairy cows, but also for the control of the energy metabolism on a herd basis and as an indicator of ketogenic feedstuffs in the ration.