[Development of aspartate aminotransferase, alanine and gamma-glutamyltransferase in the blood serum of dairy cows during the last month of pregnancy and the puerperium in relation to liver function].

Over the period of two years, the blood serum of dairy cows from three localities was examined repeatedly for the activities of aspartate aminotransferase (EC 2.6.1.1) (AST), alanine aminotransferase (EC 2.6.1.2) (ALT) and gammaglutamyltransferase (EC 2.3.2.1) (GMT). First examinations were performed two to four weeks before the expected term of delivery, the repeated examinations between the sixth and eighth week after delivery. The results obtained were used to calculate AST/ALT and GMT/ALT indexes in the studied group of animals (n = 12). As found out, the decrease in these indexes or the equality of values from the sixth to the eighth week after delivery, as compared with the period of two to four weeks prior to delivery, were connected with the clinically detectable disturbances of puerperium, i. e. inflammable discharge from the reproductive organs of dairy cows; this was observed even in the cases when the enzymatic activity was within the references standards.