Few reference values for use in metabolic profile tests for the maintenance of high productivity and the prevention of production diseases have been reported in Japanese Black beef cattle. To obtain basic data, 101 healthy steers at farms with high productivity and low frequencies of disease and death in Miyazaki Prefecture, Japan, were examined for the values of their serum components in this preliminary study. At the later fattening stage (5 to 20 months after introduction), statistically significant increases were observed in the mean serum activities of lactic dehydrogenase, glutamic-oxalacetic transaminase, gamma-glutamyl transpeptidase, and creatine phosphokinase, the mean serum contents of triglyceride, total cholesterol, albumin (Alb), total protein, blood urea nitrogen, magnesium, and vitamin E, and the mean serum calcium (Ca)/inorganic phosphorus (IF) ratio, and statistically significant decreases were seen in the mean serum alkaline phosphatase activity and the mean serum contents of glucose, IF, and vitamin A. The mean serum Alb/globulin ratio and the mean serum Ca and nonesterified fatty acids contents demonstrated no statistically significant changes.
