Sd. Crissey et al., Hepatic iron accumulation over time in European starlings (Sturnus vulgaris) fed two levels of iron, J ZOO WILD, 31(4), 2000, pp. 491-496
European starlings (Sturnus vulgaris) were used as a passerine bird model t
o examine the effect of dietary iron on the level of hepatic iron in birds.
Nestling and fledgling starlings (n = 56) were raised on a controlled-iron
diet. When birds maintained constant body weight, they were assigned in pa
irs to cages, and baseline sampling was performed. Pairs were then assigned
to one of two diets: the controlled-iron diet (168 ppm, dry basis) or a hi
gh-iron diet (3,035 ppm, dry basis). Dry-matter intake and iron consumption
were recorded. Dry-matter intake did not differ between the dietary treatm
ent groups and was stable during treatment periods. Iron intake was higher
in the high-iron group (P < 0.05). Birds were euthanized at baseline, 8 wk,
and 16 wk. Body, liver, and spleen weights were measured. Hepatic iron and
copper concentrations were determined. Body weight did not differ between
the two treatment groups or among individuals for the study duration. Liver
iron concentration differed over time and between treatment groups. Birds
receiving both treatments had similar liver iron content at week 8 (3,107 /- 228.6 ppm and 3,122 +/- 306.2 ppm high and controlled iron, respectively
; P > 0.05), but by week 16, birds consuming the high-iron diet had greater
hepatic iron levels than those consuming the controlled-iron diet (5,929 /- 937.2 ppm and 3,683 +/- 229.5 ppm high and controlled iron, respectively
; P < 0.05). Birds on the controlled-iron diet also had higher hepatic iron
at 16 wk than at 8 wk. Liver copper decreased over time in all birds regar
dless of treatment. Results show that both dietary iron level and duration
of time influenced hepatic iron storage. The controlled-iron diets still al
lowed accumulation of hepatic iron in an 8-wk period.