Characterization of Capillary Zone Electrophoresis in Horses and Donkeys

There are no capillary zone electrophoresis (CZE) comparative studies between horses and donkeys. Our objectives were to compare CZE results between both species, establish reference intervals (Ris), study age- and sex-related changes, determine the prevalence of bisalbuminemia, and correlate spectrophotometric albumin results with those calculated based on two different CZE methods. We performed CZE in 50 healthy horses and 49 healthy donkeys. There were significant differences (p < 0.03) in every protein fraction percentage and concentration (except for the β-globulins percentage) between both species, underlining the necessity of species-specific RIs. Considering the correlation to spectrophotometric results, the cathodal shoulder of the albumin should be kept in this fraction when performing CZE. Age- and sex-related differences in globulin fractions were noted in horses, but not in donkeys. Bisalbuminemia was a common finding in horses (36% of the animals), but was seldom observed in donkeys (4%). Further studies are warranted to investigate the clinical implications of these findings.