Erythrocyte Changes, Serum Iron Concentration and Performance Following Iron Injection in Neonatal Beef Calves2

Abstract

The injection of iron-dextran into beef calves at an early age immediately increased values for erythrocyte (RBC) numbers, hemoglobin (Hb) concentration, packed cell volume (PCV), mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV), even though the calves were not anemic. There were no significant differences in average daily gain (ADG) from birth through 15 wk between those that were injected and those that were not injected. Hereford calves had lower values for PCV, Hb, MCH and MCV than Angus and crossbred calves, and both Hereford and Angus calves had lesser body weight and slower ADG than crossbred calves. Serum iron (Fe) concentrations were higher in calves born in the spring and pastured in the summer than in calves born in late summer and fall and pastured in the fall. The serum Fe concentration of calves at first sampling (during first week of life) was positively correlated with their weight at that and subsequent times to 15 wk. Mean corpuscular volume and MCH in cows before calving were positively correlated with the MCV and MCH in their calves at first sampling. Serum Fe concentration in cows before calving was negatively correlated with the ADG of their calves through 15 wk.

Effects of Parenteral Supply of Iron on RBC Parameters, Performance, and Health in Neonatal Dairy Calves

“…In another study, there was no significant effect of iron injection in average daily gain from birth through 15 weeks in beef calves in comparing with those that were not received iron injection [8]. In agreement with the results of the present study, Geisser et al [10] and Sakozy et al [7] reported that, by the administration of iron, a better weight gain resulted.…”

“…However, Bunger et al [5] concluded that unrestricted feeding on concentrate rich in iron during colostral feeding period did not prevent Fe deficiency and believed that anemia developing in the first month of life was not physiological but was due to Fe deficiency. Numerous studies showed that the administration of iron to calves (orally or parenterally) provided an increase in hematological parameters and a better growth in calves [6][7][8][9][10][11][12][13][14][15]. On the other hand, there is a report that indicated iron supplementation (injection) had no effect on red blood cell (RBC) parameters and health of supplemented calves [16].…”

Parenteral Iron: Pharmacology and Clinical Use

“…However, based on available evidence [25, 33, 34], it is doubtful whether this thesis is true in patients with chronic renal failure. Both human [31, 33, 35, 36]and animal [37]studies show that the hematocrit may rise after intravenous iron administration even in the absence of anemia or iron deficiency.…”

Evidence that Adequacy of Dialysis Modulates Uremic Anemia

“…Moreover, as has been shown by both human and animal studies, hematocrit may increase after administration of intravenous iron even in the absence of anemia or iron deficiency [14, 15, 16, 17]. This observation is instructive when guiding intravenous iron use in hemodialysis patients where an increase in hematocrit after iron infusion may be interpreted as confirmation of iron deficiency.…”