R. O. V. Ravenswaay, P. R. Henry, C. B. Ammerman
Apr 16, 2001
Citations
0
Influential Citations
13
Citations
Quality indicators
Journal
Animal Feed Science and Technology
Abstract
Abstract Two experiments were conducted to investigate the effects of time and dietary Fe on tissue Fe concentrations following short-term, high level supplementation for use as a bioassay procedure for supplemental Fe sources for ruminants. In Experiment 1, 28 wethers were allotted randomly to four experimental diets which were fed for 15 or 30 days. The basal maize–soyabean meal–cottonseed hulls diet (193 mg kg −1 Fe) was supplemented with 0, 400, 800 or1200 mg kg −1 added Fe from reagent grade ferrous sulfate (FeSO 4 ·7H 2 O). Iron concentrations in liver, kidney, and spleen increased ( P −1 Fe) supplemented with 0, 300, 600 or 900 mg kg −1 added Fe from ferrous sulfate or 600 mg kg −1 Fe from ferrous carbonates A, B, or C. Liver Fe concentrations from sheep fed ferrous sulfate were numerically greater than those of animals fed the carbonate sources or control diet. Kidney Fe concentrations from lambs fed ferrous sulfate at 600 mg kg −1 Fe or carbonate-A were greater ( P P −1 Fe as ferrous sulfate, but were similar to other carbonates. Overall average bioavailability estimates based on multiple regression slope ratios for the three tissues were ferrous sulfate 1.00, carbonate-A 0.55, carbonate-B 0.00, and carbonate-C 0.20. Estimates for carbonates A and C were similar to those based on hemoglobin concentrations reported previously for young swine supplemented at dietary concentrations near the requirement.