Comparison of Electrophoretic and Bromocresol Green Albumin Methods in Chickens and Other Veterinary Species

Abstract

Background: The bromocresol green albumin assay (ALBBCG) has been used in birds and reportedly is noncomparable with electrophoretic albumin (ALBPE) in many species. It is accepted for use in some species and rejected in others. Objectives: We aimed to compare the performance of ALBPE and ALBBCG methods within backyard chickens and compare the performance of ALBBCG in chickens with other veterinary species where the ALBBCG method is accepted and used clinically. Methods: Chicken plasma collected during reference interval development and samples submitted for diagnostic biochemistry profile were evaluated using the ALBBCG and ALBPE assays. Method comparison was performed according to current recommendations, including the use of Passing–Bablok and Bland–Altman analysis. ALBBCG and ALBPE were also measured in other avian species, dogs, cats, horses, and domestic ruminants. Method comparison was evaluated within and between species, including clinical utility based on the percentage of cases discordantly interpreted as hypo-, normo-, or hyperalbuminemic by ALBBCG and ALBPE. Results: In chickens, ALBBCG and ALBPE were not comparable, having a constant bias (−0.4 g/dL) and proportional bias. Similarly, the methods were not comparable in other species; > 10% of samples had > TEA (15%) difference in all species. The clinical utility of albumin interpretation in chickens did not differ significantly from that in dogs and horses, as determined by ANOVA. Conclusions: The data suggest that ALBBCG is not comparable with ALBPE and performs similarly across all tested species. There is no evidence to support the continued rejection of the ALBBCG in chicken and other avians and acceptance in some mammals.