Enzyme‐linked immunosorbent assay to quantitate serum ferritin in the northern fur seal (Callorhinus ursinus)

Abstract

Serum ferritin concentration correlates with tissue iron stores in humans, horses, calves, dogs, cats, and pigs. Serum ferritin is considered the best serum analyte to predict total body iron stores in these species, and is more reliable than serum iron or total iron-binding capacity, both of which may be affected by disorders unrelated to iron adequacy or excess (including hypoproteinemia, chronic infection, hemolytic anemia, hypothyroidism, renal disease, and drug administration). Iron overload has been documented to result in hemochromatosis in captive northern fur seals (Callorhinus ursinus); therefore, we developed an enzyme-linked immunosorbent assay (ELISA) to measure serum ferritin in this species. The assay uses two murine anti-canine ferritin monoclonal antibodies in a sandwich arrangement that was originally used in an ELISA to measure serum ferritin in dogs. Ferritin isolated from fur seal liver was used as a standard. Ferritin standards were linear from 0 to 50 ng/ml. Recovery of purified ferritin from fur seal serum varied from 89% to 99%. The within-assay variability was 6%, and the assay-to-assay variability for two different samples was 10% and 16%.

Haemochromatosis in a Brazilian tapir (Tapirus terrestris) in an Australian zoo

“…The assay providing the most reliable indicator of whole body iron concentration is serum ferritin. Although initially thought to be species‐specific, 16 this assay has been validated across large evolutionary divides within mammalian Orders (horses to rhinoceros and dogs to seals, respectively) 8,17 and will only produce positive results if suitable cross‐reactivity exists. The elevation of circulating ferritin in these two animals is evidence of increased tissue iron concentration, to which it is closely correlated in steady‐state situations, and indirectly suggests chronically elevated serum iron.…”

The impact of lactation strategy on physiological development of juvenile marine mammals: implications for the transition to independent foraging

“…Percent saturation was calculated as serum iron/TIBC. Serum ferritin concentration was measured by ELISA [24]. All iron assays were carried out at the Kansas State University College of Veterinary Medicine.…”