Three hundred healthy female Holstein calves were used for assess the liver function throughout the first month of life. The following serum biochemical variables were analysed: bilirrubin (total, direct and indirect) and the activities of gamma glutamyltransferase (GGT), aspartate aminotransferase (AST) and creatine kinase (CK). The influence of age on the biochemical values was also studied. The bilirrubin values had highest levels on the 1st d of life (BT-1.360mg/dl; BC-0.150mg/dl e BL-1.175mg/dl) and then showed a continuing decrease until the 30th d of life (BT-0.350mg/dl; BC-0.050mg/dl e BL-0.300mg/dl). The serum GGT activities were at they highest point between the 16th to 24th h (945.00UI/L). There was a downward trend from the 11th d (86.00UI/), presenting the lowest activity at the 30th d (24.00UI/) similar to the activities usually found in healthy adult dairy cattle. The activities of AST and CK were higher at the 1st d of life (AST- 27.50UI/L e CK- 73.00UI/L) declining from then on (AST- 19.00UI/L e CK-41.50UI/L). Ageing showed a significant influence on all the biochemical variables studied.
liver function; calves; newborn; clinical biochemistry
