Serum ferritin, serum iron, and erythrocyte values in foals.
Twenty-one healthy Thoroughbred and Quarter Horse foals were studied from birth until 1 year of age. Foals had access to an iron-supplemented creep feed before weaning and were fed an iron-supplemented concentrate as part of their diet after weaning at 4 months of age. Initial blood samples were taken before foals were allowed to nurse. Serum iron concentration, total iron-binding capacity, and PCV decreased during the foal's first 24 hours of life. Serum iron concentration decreased rapidly from 446 +/- 16 micrograms/dl (mean +/- SE) at birth to 105 +/- 11 micrograms/dl at 3 days of age. Serum ferritin concentration increased from a mean of 85 +/- 8 ng/ml at birth to 159 +/- 11 ng/ml at 1 day of age. Thereafter, ferritin concentration decreased gradually to a minimum of 61 +/- 6 ng/ml at 3 weeks of age, and then at 6 months increased to values similar to those from reference adult horses. The ferritin concentration in colostrum at birth was 354 +/- 42 ng/ml, compared with 25 +/- 2 ng/ml in milk 1 day later. The decrease and then increase in serum ferritin concentration occurred concomitantly with opposite changes in serum total iron-binding capacity. The mean PCV decreased gradually to a minimum at 3 months of age. This decrease was associated with an increasing number of microcytes, as determined with a cell-size distribution analyzer.
Harvey
J W
JW
Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville 32610.
Asquith
R L
RL
Sussman
W A
WA
Kivipelto
J
J
D000375:Aging / Q000097:blood; D000818:Animals; D000831:Animals, Newborn / Q000097:blood*; D001682:Biological Availability; D004909:Erythrocyte Indices / Q000662:veterinary*; D005260:Female; D005293:Ferritins / Q000097:blood*; D006736:Horses / Q000097:blood*; D007501:Iron / Q000097:blood*; D008297:Male
D005293:Ferritins; D007501:Iron