乳牛における血漿オルニチンカルバミルトランスフェラーゼ活性の病態的意義

Abstract

Ornithine Carbamoyltransferase (OCT) is recognized as a liver parenchyma enzyme. To clarify the pathophysiological significance of its activities, γ-glutamyl transferase (CGT) and aspartate transaminase (AST) were evaluated in 16 healthy and 106 sick dairy cows. Liver weight and liver triglyceride (TG) levels were measured in some of the animals, on which autopsies were performed. Although plasma OCT activity was 2-9 IU in healthy cows, it tended to rise in some diseased cows, especially when conditions like liver congestion brought on by cardiovascular disorders and hepatic fibroses resulted in liver enlargement. It did not necessarily increase, however, in cases of fatty liver. Hepatic disorder was more probable when OCT was high than when GGT or AST was high. Examination of plasma OCT activities provides useful information for evaluating liver disturbances in dairy cows.