Iron and Copper Availability from Various Sources

Abstract

A total of 1110 broiler cockerels were used in three experiments to determine the availability of iron and copper from various sources. A skim milk basal diet was fed in each experiment using chicks maintained in battery brooders beginning at one day of age. Four organic iron compounds (sequestered iron A1 and ferric choline chloride2 in Experiment 1 and sequestered iron B and C1 in Experiment 2), ferrous sulfate and ferric oxide were the test iron compounds used in Experiments 1 and 2. Added dietary iron levels furnished by the test compounds were 10 and 20 p.p.m. (Experiment 1) and 5 and 10 p.p.m. (Experiment 2). The test copper compounds fed in Experiment 3 were added to furnish 1 and 2 p.p.m. copper using cupric sulfate, cuprous oxide and cuprous iodide.No consistent differences in hemoglobin content, hematocrit (packed cell volume), chick weight and mortality were observed between ferrous sulfate and the four organic iron compounds; however, these compounds were significantly superior to ferric oxide. Hemoglobin content, hematocrit and liver copper content were significantly increased when cupric sulfate was fed as compared to results obtained with cuprous iodide or cuprous oxide. Increased chick weight gain and decreased mortality were observed with chicks fed cupric sulfate or cuprous iodide as compared to those fed cuprous oxide.Chick availability values for ferric oxide (71 and 82%) were approximately three-quarters that of ferrous sulfate. The organic sources of iron gave high availability values (91–131%), although ferric choline chloride was not as available to the chick as the sequestered iron compounds (93–131%) as determined by regression analysis method and relative biological availability. Cuprous iodide and cuprous oxide have essentially equal availability, but the availability of these copper sources is only three-quarters that of cupric sulfate.