Immune functions of veal calves fed low amounts of iron.
Immune functions were studied in male calves fed milk replacer (MR) containing 10 or 50 mg iron (Fe)/kg. Calves fed 10 mg Fe/kg MR developed marked hypoferremia and anemia, whereas serum-Fe and haemoglobin concentration of calves fed 50 mg Fe/kg MR were normal. Growth performance was reduced, while feed/gain ratio, incidence of infections (especially pneumonias), febrile body temperatures and antibiotic treatments were higher in calves fed 10 than 50 mg Fe/kg MR (p < 0.05). Whereas antibody production (to horse erythrocytes) and lymphocyte stimulation (by mitogens) were not significantly altered, cell-mediated immunity (measured as cutaneous delayed-type hypersensitivity reaction to dinitrofluoro-benzene), number of neutrophils with phagocytic capacity, activity of the Fe-containing enzyme myeloperoxidase, blood serum IgG concentration and the number and diameter of germinal centres as a measure of the number and production of B-cells in cervical superficial lymph nodes in calves fed 10 mg Fe/kg MR were reduced when compared with calves fed 50 mg Fe/kg MR (p < 0.05). In conclusion, severe Fe deficiency caused reduced growth performance, associated with and partly due to higher incidence of infections because of defective immune reactions.
Gygax
M
M
Division of Nutrition Pathology, University of Berne, Switzerland.
Hirni
H
H
Zwahlen
R
R
Lazary
S
S
Blum
J W
JW
D000818:Animals; D000917:Antibody Formation; D002417:Cattle / Q000276:immunology*; D002418:Cattle Diseases / Q000276:immunology*; D007111:Immunity, Cellular; D007239:Infections / Q000276:immunology / Q000662:veterinary*; D007501:Iron / Q000008:administration & dosage*; D000090463:Iron Deficiencies; D008297:Male; D010587:Phagocytosis
D007501:Iron