The electrophoretic patterns of the serum enzymes lactate dehydrogenase and creatine kinase from water buffalo calves are described. Differences in total activities as well as their relative distribution were seen at ages ranging from 1 to 10 weeks. While total lactate dehydrogenase activity increased by over 100%, total creatine kinase increased by almost 400%. The relative activities of lactate dehydrogenase 1 and 5 decreased with age. Lactate dehydrogenase 2 and 3 increased and lactate dehydrogenase 4 did not change. In relation to creatine kinase, the prevalent isoenzyme was creatine kinase-MM, but it's relative activity gradually decreased in comparison to the other two isoenzymes (creatine kinase-MB and creatine kinase-BB). Creatine kinase-BB was completely absent until the 3rd week of age. The percentage modifications of creatine kinase isoenzymes were correlated to age. The results suggest that isoenzymatic separation and characterization of lactate dehydrogenase and creatine kinase in relation to the various tissues can significantly contribute to the diagnosis of diseases which are linked to tissue damage.