An automated method for the measurement of methaemoglobin in avian blood

An automated method has been developed for the measurement of methaemoglobin (metHb) in blood using a biochemistry analyser. The method was validated using blood collected from red-legged partridges exposed in vitro to increasing concentrations of nitrite in order to obtain different percentages of metHb. Results obtained using the original manual method and those using the new automated technique were compared and no significant differences were found. Intra-day and inter-day variabilities (8.8% and 2.6%, respectively) were acceptable for samples containing high levels (63–81%) of metHb. Methaemoglobin measured in blood samples stored in liquid nitrogen was stable for 10 days, but increased significantly by day 20 in nitrite-treated samples.