Plasma glucose, mannose, and non-esterified fatty acid concentrations in layer-type chickens.

1. The oral administration of glucose or dietary glucose reduces fasting plasma mannose concentrations in mammals. On the other hand, there have been no reports on plasma mannose levels in birds. We have analysed chicken plasma mannose and glucose by an original high-performance liquid chromatography (HPLC) method, together with plasma non-esterified fatty acid (NEFA) concentrations in chickens. 2. Plasma glucose concentrations of chickens did not differ among three different age groups (0, 18 and 150 d). However, the plasma mannose concentrations of chicks at the age of 0 d were higher than those of chickens at the ages of 18 and 150 d. 3. At the age of 18 and 150 d, plasma glucose concentrations were elevated and plasma mannose and NEFA concentrations were decreased after regular feeding, compared to fasting levels.