Enzyme variation in Eimeria species of the chicken.

A method for the biochemical identification of protozoa belonging to the genus Eimeria is described for the first time. Starch gel electrophoresis of the enzymes lactate dehydrogenase, glucose phosphate isomerase, 6-phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenase from parasite extracts revealed both intra- and inter-species differences when 11 strains representative of 6 species of Eimeria were examined. Oocysts were the most accessible parasite stage for investigation but sporozoites and merozoites of an embryo-adapted strain of E. tenella were also examined for enzyme activity.