Serum indices of body stores of iron in northern fur seals (Callorhinus ursinus) and their relationship to hemochromatosis
Publication Type: |
Journal Article |
Year of Publication: |
2004 |
Authors: |
Lisa M. Mazzaro, J. Lawrence Dunn, David J. St. Aubin, Gordon A. Andrews, Patricia S. Chavey |
Publication/Journal: |
Zoo Biology |
Publisher: |
A Wiley Company, Inc., Wiley Subscription Services |
Keywords: |
ferritin, hemochromatosis, iron storage disease, northern fur seals (callorhinus ursinus), percent saturation, tibc |
ISBN: |
1098-2361 |
Abstract:
Abstract 10.1002/zoo.10126.abs Iron storage disease (hemochromatosis) has been reported in many species of both captive and free-ranging animals. In this study we examined the relationship between this disease and concentrations of iron analytes in aquarium-held northern fur seals (Callorhinus ursinus). Sera were analyzed for iron, total iron-binding capacity (TIBC), ferritin, ceruloplasmin, and haptoglobin concentrations in a retrospective study that included samples taken over a 14-year period. The animals ranged in age from <1 year to an estimated 23 years. Serum ferritin was measured using an enzyme-linked immunosorbent assay (ELISA) for canine sera. The results from this assay are the first reported for any pinniped. Serum iron concentrations in presumed healthy animals ranged from 37 to 196 µg/dl, and TIBC ranged from 136 to 484 µg/dl. The transferrin saturation percentage differed significantly between male (41%) and female (63%) adult fur seals, as did the ferritin levels (54 ng/ml for males vs. 500 ng/ml for females). There was a trend toward increased serum ferritin and percent transferrin saturation with age, especially in females. The data also showed a relationship between serum iron and transferrin saturation among eight mother–pup pairs, which suggests that pups may develop increased iron levels due to placental transfer of iron and/or transfer of iron through the milk from iron-overloaded females. Diet was considered as a factor in the development of hemochromatosis in at least three geriatric female northern fur seals, and their diets were analyzed for iron concentrations. On the basis of these results, the diets were altered by replacing a portion of the high-iron-content fish (herring) with a lower-iron-content item (squid), and discontinuing iron and vitamin C supplementation (via a multivitamin tablet). Sera were analyzed before, and 1 and 4 years after the dietary changes were implemented. Paired t-tests showed no significant changes in the iron analytes from pre- to post-diet-change samples, which indicates that it may be too late to affect iron levels by diet alone in older animals with a chronic history of elevated iron levels. Zoo Biol 23:205–218, 2004. © 2004 Wiley-Liss, Inc.